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Anti-proliferative and apoptotic effects of anandamide in human prostatic cancer cell lines: Implication of epidermal growth factor receptor down-regulation and ceramide production

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Abstract

Anandamide (ANA) is an endogenous lipid which acts as a cannabinoid receptor ligand and with potent anticarcinogenic activity in several cancer cell types. The inhibitory effect of ANA on the epidermal growth factor receptor (EGFR) levels expressed on the EGF-stimulated prostatic cancer cells LNCaP, DU145, and PC3 was estimated by ELISA tests. The anti-proliferative and cytotoxic effects of ANA were also evaluated on these human prostatic cancer cell lines by growth tests, flow cytometric analyses, trypan blue dye exclusion assays combined with the Papanicolaou cytological staining method. ANA induced a decrease of EGFR levels on LNCaP, DU145, and PC3 prostatic cancer cells by acting through cannabinoid CB(1) receptor subtype and this leaded to an inhibition of the EGF-stimulated growth of these cells. Moreover, the G(1) arrest of metastatic DU145 and PC3 growth was accompanied by a massive cell death by apoptosis and/or necrosis while LNCaP cells were less sensitive to cytotoxic effects of ANA. The apoptotic/necrotic responses induced by ANA on these prostatic cancer cells were also potentiated by the acidic ceramidase inhibitor, N-oleoylethanolamine and partially inhibited by the specific ceramide synthetase inhibitor, fumonisin B1 indicating that these cytotoxic actions of ANA might be induced via the cellular ceramide production. The potent anti-proliferative and cytotoxic effects of ANA on metastatic prostatic cancer cells might provide basis for the design of new therapeutic agents for effective treatment of recurrent and invasive prostatic cancers.

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... Cannabinoids have been shown to be promising anticancer agents in prostate cancer treatment [5]. In prostate cancer patients, high expression of CB1 has been associated with a worse prognosis [6,7], and several authors reported CB1-mediated anti-proliferative and anti-invasive effects of cannabinoids in prostate cancer cells [8][9][10][11][12]. Furthermore, it has been recently demonstrated that CB2 also controls tumor cells proliferation, migration, and invasion in both prostate cancer cell lines and in vivo models [13]. ...
... Several studies have already described the anti-proliferative effects of exogenous administrated endocannabinoids in prostate cancer cells [6][7][8][9][10][11][12]. The two primary endocannabinoids are Narachidonoylethanolamine (anandamide, AEA), which binds CB1 with high affinity, but it is unable to activate CB2, and 2-arachydonoyl glycerol (2-AG), which acts as full agonist for both CBs [31,32]. ...
... The two primary endocannabinoids are Narachidonoylethanolamine (anandamide, AEA), which binds CB1 with high affinity, but it is unable to activate CB2, and 2-arachydonoyl glycerol (2-AG), which acts as full agonist for both CBs [31,32]. It has been proven that AEA inhibits cell proliferation either in androgen-sensitive or insensitive prostate cancer cell lines via CB1 [9,10,33]. Furthermore, both AEA and 2-AG have been shown able to induce apoptosis both in tumor cell lines and in primary cultures of prostate cancer cells [7]. However, the contribution of an autocrine loop of endocannabinoids in modulating cancer aggressiveness it has been described only in a very few studies. ...
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Endo-, phyto- and synthetic cannabinoids have been proposed as promising anti-cancer agents able to impair cancer cells’ behavior without affecting their non-transformed counterparts. However, cancer outcome depends not only on cancer cells’ activity, but also on the stromal cells, which coevolve with cancer cells to sustain tumor progression. Here, we show for the first time that cannabinoid treatment impairs the activation and the reactivity of cancer-associated fibroblasts (CAFs), the most represented stromal component of prostate tumor microenvironment. Using prostate cancer-derived CAFs, we demonstrated that WIN 55-212.2 mesylate, a synthetic full agonist of cannabinoid receptors (CBs) 1 and 2, downregulates α-smooth muscle actin and matrix metalloprotease-2 expression, and it inhibits CAF migration, essential features to ensure the activated and reactive CAF phenotype. Furthermore, by impairing stromal reactivity, WIN 55-212.2 mesylate also negatively affects CAF-mediated cancer cells’ invasiveness. Using selective antagonists of CBs, we proved that CAFs response to WIN 55-212.2 mesylate is mainly mediated by CB2. Finally, we suggest that endocannabinoids self-sustain both prostate tumor cells migration and CAFs phenotype by an autocrine loop. Overall, our data strongly support the use of cannabinoids as anti-tumor agents in prostate cancer, since they are able to simultaneously strike both cancer and stromal cells.
... Cannabinoids prevented the inhibition of RAF1 (caused by protein kinase A-induced Raf phosphorylation) and induced prolonged activation of the RAF1-MEK-ERK signalling cascade, leading to downregulation of PRLr and Trk [14]. Mimeault et al. [16] showed that a micromolar concentration of AEA inhibited EGF-induced proliferation of DU145 and PC3 cells (androgen independent human prostate cancer cell lines overexpressed EGF-R) as well as of androgen-stimulated LNCaP, via G1 arrest, and downregulated EGF-R levels. Both phenomena were CB1-mediated. ...
... It is important to remark that longer AEA incubation times (5-6 days) were able to induce massive apoptosis in DU145 and PC3 cells. This effect was mediated by CB1/2 receptors via cellular ceramide accumulation, and was absent in LNCaP cells [16]. ...
... In any case, many factors can affect the relation between ERK activation and cell fate, given that prolonged ERK stimulation mediates cell-cycle arrest and even cell death (42). Mimeault et al. reported that in prostate tumor cells, pharmacological inhibition of de novo ceramide synthesis led to prevention of cannabinoid-induced cell death (43). ...
... Similar results of cell-cycle arrest following cannabinoid receptor activation have been reported in skin and prostate cancer cells. In these studies, growthfactor-receptor signaling is inhibited (43,46). It is likely that a general underlying mechanism of cannabinoid antitumor action exists. ...
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Pancreatic cancer is one of the most fatal malignancies, and therefore, new strategies, which aim at the improvement of the prognosis of this lethal disease, are needed. Many clinical trials have failed to improve overall survival. Nowadays, research is focused on advances provided by novel potential targets to efficiently enhance life expectancy. Cannabinoids, the active components of Cannabis sativa L., and their derivatives, have been reported as palliative adjuvants to conventional chemotherapeutic regimens. Cannabinoid effects are known to be mediated through the activation of cannabinoid receptors. To date, two cannabinoid receptors, cannabinoid receptor 1 and 2, have been cloned and identified from mammalian tissues. Cannabinoids exert a remarkable antitumoral effect on pancreatic cancer cells, due to their ability to selectively induce apoptosis of these cells. This review strengthens the perception that cannabinoid receptors might be useful in clinical testing to prognose and treat pancreatic cancer. Many studies have tried to describe the mechanism of cell death induced by cannabinoids. The aim of this review is to discuss the effects of cannabinoid receptors in pancreatic cancer in order to provide a brief insight into cannabinoids and their receptors as pancreatic cancer biomarkers and in therapeutic strategies.
... It has also been found that CB2 plays a more important role than CB1 in bringing about the anticancer activity of cannabinoids. 46 Also, the concentration of cannabinoid receptors on tumour cells has been found to be much higher than on the corresponding normal tissue in different cancer types. For instance, CB2 expression in human epidermal growth factor receptor-2 (HER2)-positive breast cancer is significantly higher (91%) than in HER2-negative breast cancers (35-72%) and normal breast tissue (5%). ...
... 54 It was also found that the endogenous cannabinoid anandamide possesses antiproliferative and apoptotic effects in human prostate cancer cell lines (LNCaP, DU145 and PC3); the effects of which being mediated by epidermal growth factor receptor (EGFR) down-regulation and ceramide accumulation. 46 Various cannabinoid analogues and various cannabinoid receptor ligands are listed in Table 3 Figure 5. ...
Article
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Cannabis has been used medicinally for centuries and numerous species of this genus are undoubtedly amongst the primeval plant remedies known to humans. Cannabis sativa in particular is the most reported species, due to its substantial therapeutic implications that are owed to the presence of chemically and pharmacologically diverse cannabinoids. These compounds have long been used for the palliative treatment of cancer. Recent advancements in receptor pharmacology research have led to the identification of cannabinoids as effective antitumor agents. This property is accredited for their ability to induce apoptosis, suppress proliferative cell signalling pathways and promote cell growth inhibition. Evolving lines of evidence suggest that cannabinoid analogues, as well as their receptor agonists, may offer a novel strategy to treat various forms of cancer. This review summarizes the historical perspective of C. sativa, its potential mechanism of action, and pharmacokinetic and pharmacodynamic aspects of cannabinoids, with special emphasis on their anticancer potentials.
... In PCa biopsy samples, tumour CB 1 receptor immunoreactivity and pAkt immunoreactivity are positively correlated, and cases with scores above the median for both parameters show a higher rate of cell proliferation than the other cases 27 . In addition to effects on ERK/Akt signalling, there are interactions between CB receptors and other important pathogenic signalling mechanisms, not least the epidermal growth factor (EGF) receptor pathway 28,29 . Further, changes in the activity of the intracellular signalling molecules can impact upon other systems known to be involved in the pathogenesis of cancer, such as the interleukin-6 receptor and androgen receptor pathways in the case of Pca [30][31][32] . ...
... The drawing is based upon refs. [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] , and in many cases synthetic-and plant-derived cannabinoids rather than endocannabinoids have been used to identify the pathways. Blue lines indicate pathways resulting in cell death/apoptosis and orange lines indicate pathways resulting in cell proliferation. ...
Article
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There is good evidence that the N-acylethanolamine (NAE)/monoacylglycerol (MAG) signalling systems are involved in the pathogenesis of cancer. However, it is not known how prostate tumours affect these systems in the surrounding non-malignant tissue and vice versa. In the present study we have investigated at the mRNA level 11 components of these systems (three coding for anabolic enzymes, two for NAE/MAG targets and six coding for catabolic enzymes) in rat prostate tissue following orthotopic injection of low metastatic AT1 cells and high metastatic MLL cells. The MLL tumours expressed higher levels of Napepld, coding for a key enzyme in NAE synthesis, and lower levels of Naaa, coding for the NAE hydrolytic enzyme N-acylethanolamine acid amide hydrolase than the AT1 tumours. mRNA levels of the components of the NAE/MAG signalling systems studied in the tissue surrounding the tumours were not overtly affected by the tumours. AT1 cells in culture expressed Faah, coding for the NAE hydrolytic enzyme fatty acid amide hydrolase, at much lower levels than Naaa. However, the ability of the intact cells to hydrolyse the NAE arachidonoylethanolamide (anandamide) was inhibited by an inhibitor of FAAH, but not of NAAA. Treatment of the AT1 cells with interleukin-6, a cytokine known to be involved in the pathogenesis of prostate cancer, did not affect the expression of the components of the NAE/MAG system studied. It is thus concluded that in the model system studied, the tumours show different expressions of mRNA coding for key the components of the NAE/MAG system compared to the host tissue, but that these changes are not accompanied by alterations in the non-malignant tissue.
... In addition, WIN-55,212-2 treatment decreased protein and mRNA expression of androgen receptor and prostate-specific antigen (PSA) and protein expression of proliferating cell nuclear antigen (PCNA), and VEGF [85]. Anandamide (at 2 μM) induced a decrease of EGFR levels on LNCaP, DU145, and PC3 prostatic cancer cells via cannabinoid CB1 receptor subtype, causing an inhibition of the EGF-stimulated growth of these cells and apoptosis and/or necrosis [86]. Endogenous 2-AG (1 μmoL/L) inhibited the invasive ability of androgen-independent prostate cancer cells as PC3, DU-145, and LNCaP cells by a mechanism involving the CB1 receptor and through the inactivation of protein kinase A [87,88]. ...
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In recent years, the endocannabinoid system has received great interest as a potential therapeutic target in numerous pathological conditions. Cannabinoids have shown an anticancer potential by modulating several pathways involved in cell growth, differentiation, migration, and angiogenesis. However, the therapeutic efficacy of cannabinoids is limited to the treatment of chemotherapy-induced symptoms or cancer pain, but their use as anticancer drugs in chemotherapeutic protocols requires further investigation. In this paper, we reviewed the role of cannabinoids in the modulation of signaling mechanisms implicated in tumor progression.
... Sundry's studies have evidenced the anti-proliferative activity of cannabinoids in prostate tumours. Anandamide inhibits the Cancers 2020, 12, 3275 9 of 21 proliferation of cells (PC-3, DU-145, and LNCaP) [98,99] and primary cultures of PC [91] via CB1R. Phytocannabinoids also reduce PC cell proliferation. ...
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The various components of the endocannabinoid system (ECS), such as the cannabinoid receptors (CBRs), cannabinoid ligands, and the signalling network behind it, are implicated in several tumour-related states, both as favourable and unfavourable factors. This review analyses the ECS’s complex involvement in the susceptibility to cancer, prognosis, and response to treatment, focusing on its relationship with cancer biology in selected solid cancers (breast, gastrointestinal, gynaecological, prostate cancer, thoracic, thyroid, CNS tumours, and melanoma). Changes in the expression and activation of CBRs, as well as their ability to form distinct functional heteromers affect the cell’s tumourigenic potential and their signalling properties, leading to pharmacologically different outcomes. Thus, the same ECS component can exert both protective and pathogenic effects in different tumour subtypes, which are often pathologically driven by different biological factors. The use of endogenous and exogenous cannabinoids as anti-cancer agents, and the range of effects they might induce (cell death, regulation of angiogenesis, and invasion or anticancer immunity), depend in great deal on the tumour type and the specific ECS component that they target. Although an attractive target, the use of ECS components in anti-cancer treatment is still interlinked with many legal and ethical issues that need to be considered.
... Although not proved, the authors suggested that EGFR and CB 2 R may be forming complexes, and that CB 2 R activation might disrupt them (43). In addition, and similar to what we observed here, pharmacological activation of CB 1 R induced the death of prostate cancer cells in culture, an effect that was accompanied by a significant down-regulation of EGFR (44), and coexpression of EGFR with CB 1 R was associated with poor patient prognosis in this type of cancer (45). These observations demonstrate a functional interaction between another cannabinoid receptor (CB 1 R) and another member of the HER family (HER1) that could be due to a mere transactivation process or to a physical interaction similar to that described here between CB 2 R and HER2. ...
Article
Although human epidermal growth factor receptor 2 (HER2)-targeted therapies have dramatically improved the clinical outcome of HER2-positive breast cancer patients, innate and acquired resistance remains an important clinical challenge. New therapeutic approaches and diagnostic tools for identification, stratification, and treatment of patients at higher risk of resistance and recurrence are therefore warranted. Here, we unveil a mechanism controlling the oncogenic activity of HER2: heteromerization with the cannabinoid receptor CB 2 R. We show that HER2 physically interacts with CB 2 R in breast cancer cells, and that the expression of these heteromers correlates with poor patient prognosis. The cannabinoid Δ ⁹ -tetrahydrocannabinol (THC) disrupts HER2–CB 2 R complexes by selectively binding to CB 2 R, which leads to ( i ) the inactivation of HER2 through disruption of HER2–HER2 homodimers, and ( ii ) the subsequent degradation of HER2 by the proteasome via the E3 ligase c-CBL. This in turn triggers antitumor responses in vitro and in vivo. Selective targeting of CB 2 R transmembrane region 5 mimicked THC effects. Together, these findings define HER2–CB 2 R heteromers as new potential targets for antitumor therapies and biomarkers with prognostic value in HER2-positive breast cancer.
... It is believed that the inhibition of proliferation may occur through adenylyl cyclase and cAMP/protein kinase A [66] , cell cycle arrest that induces the kinase inhibitor p27 kip , the decreasing of epidermal growth factor receptor (EGF-R) expression or lower activity of EGF-R tyrosine kinase; low levels of nerve growth factor (NGF) and prolactin and vascular endothelial growth factor tyrosine kinase receptors (VEGF-R tyrosine kinase) Cell cycle arrest that induces the kinase inhibitor p27 kip , the decreasing of epidermal growth factor receptor (EGF-R) expression or lower activity of EGF-R tyrosine kinase; low levels of nerve growth factor (NGF) and prolactin and vascular endothelial growth factor tyrosine kinase receptors (VEGF-R tyrosine kinase). [67] Anandamide stops the proliferative effects of human thyroid carcinoma, cholangiocarcinoma, breast cancer, non-melanoma skin cancer and hepatocellular carcinoma. This endocannabinoid suspends breast cancer cell proliferation through the inhibition of brca 1 gen, because of this action helps to the down regulation of prolactin receptor. ...
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Cancer is a complex pathophysiological condition that produces an important number of death around the world. At present, there are different ways to treat cancer: chemotherapy, radiotherapy and surgery. Cancer chemotherapy used today in many cases is effective, but it is very toxic too. The endocannabinoid system is implicated in a variety of physiological and pathological processes, including cancer. Many studies have shown, since 1975, that both phytocannabinoids Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) offer an antioneoplastic activity. Latter, other researchers have displayed that endocannabinoids as anandamide (ANA) and 2-arachidonoylglycerol (2-AG) also present the same potential activity. Phytocannabinoids and endocannabinoids act through CB1 and CB2 receptors to produce that effect. However, THC -the main phytocannabinoid presenting anticancer action- as well as anandamide employed in pharmacological doses, produce important phycotropic effects, but these cannabinoid compounds do not produce major adverse reactions like conventional antineoplastic drugs. On this basis, scientists have to develop analogs or derivatives of cannabinoids/endocannabinoids that cannot induce psychotropic effects. It is important to study more deeply chronopharmacological aspects of cannabinoids/endocannabinoids in cancer therapy, although some is known today.
... Non-melanoma skin cancer: JWF2 cells Induces apoptosis mediated by oxidative stress and by CB receptorindependent endocannabinoid signaling Breast cancer: MCF-7 and EFM-10 cells Blocks cancer proliferation through CB1R-mediated inhibition of endogenous prolactin action (Di Marzo et al., 1998) Neuroblastoma: N18TG2 cells Neuroprotection from apoptosis mediated by FAAH (Matas et al., 2007) Prostate cancer: PC-3 cells Inhibits cancer cell proliferation via CB1R (Mimeault et al., 2003) Gastric cancer: human AGS adenocarcinoma cells Apoptosis induction (Ortega et al., 2016) Prostate cancer: LNCaP Upregulation of androgen receptor expression (Sánchez et al., 2003) Breast cancer: MDA-MB-231 ...
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Cannabis has long been known to limit or prevent nausea and vomiting, lack of appetite, and pain. For this reason, cannabinoids have been successfully used in the treatment of some of the unwanted side effects caused by cancer chemotherapy. Besides their palliative effects, research from the past two decades has demonstrated their promising potential as antitumor agents in a wide variety of tumors. Cannabinoids of endogenous, phytogenic, and synthetic nature have been shown to impact the proliferation of cancer through the modulation of different proteins involved in the endocannabinoid system such as the G protein-coupled receptors CB1, CB2, and GRP55, the ionotropic receptor TRPV1, or the fatty acid amide hydrolase (FAAH). In this article, we aim to structurally classify the antitumor cannabinoid chemotypes described so far according to their targets and types of cancer. In a drug discovery approach, their in silico pharmacokinetic profile has been evaluated in order to identify appropriate drug-like profiles, which should be taken into account for further progress toward the clinic. This analysis may provide structural insights into the selection of specific cannabinoid scaffolds for the development of antitumor drugs for the treatment of particular types of cancer.
... The eCB system is implicated in cancer and tumor progression. Thus, eCBs have been shown to affect proliferation, invasive properties, migration and adhesion of human cancer cells, including prostate cancer cells[11][12][13][14]. Human androgen-sensitive LNCaP cells express FAAH, and it knockdown with siRNA reduces the invasivity of these cells across Matrigelcoated transwells in response to fibroblast conditioned media[15]. ...
Article
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Tumour necrosis factor α (TNFα) is involved in the pathogenesis of prostate cancer, a disease where disturbances in the endocannabinoid system are seen. In the present study we have investigated whether treatment of DU145 human prostate cancer cells affects anandamide (AEA) catabolic pathways. Additionally, we have investigated whether cyclooxygenase-2 (COX-2) can regulate the uptake of AEA into cells. Levels of AEA synthetic and catabolic enzymes were determined by qPCR. AEA uptake and hydrolysis in DU145 and RAW264.7 macrophage cells were assayed using AEA labeled in the arachidonic and ethanolamine portions of the molecule, respectively. Levels of AEA, related N-acylethanolamines (NAEs), prostaglandins (PG) and PG-ethanolamines (PG-EA) in DU145 cells and medium were quantitated by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC–MS/MS) analysis. TNFα treatment of DU145 cells increased mRNA levels of PTSG2 (gene of COX-2) and decreased the mRNA of the AEA synthetic enzyme N-acyl-phosphatidylethanolamine selective phospholipase D. mRNA levels of the AEA hydrolytic enzymes fatty acid amide hydrolase (FAAH) and N-acylethanolamine-hydrolyzing acid amidase were not changed. AEA uptake in both DU145 and RAW264.7 cells was inhibited by FAAH inhibition, but not by COX-2 inhibition, even in RAW264.7 cells where the expression of this enzyme had greatly been induced by lipopolysaccharide + interferon γ treatment. AEA and related NAEs were detected in DU145 cells, but PGs and PGE2-EA were only detected when the cells had been preincubated with 100 nM AEA. The data demonstrate that in DU145 cells, TNFα treatment changes the relative expression of the enzymes involved in the hydrolytic and oxygenation catabolic pathways for AEA. In RAW264.7 cells, COX-2, in contrast to FAAH, does not regulate the cellular accumulation of AEA. Further studies are necessary to determine the extent to which inflammatory mediators are involved in the abnormal endocannabinoid signalling system in prostate cancer.
... This was also highlighted by Mimeault et al, 42 who showed that AEA application in DU145, LNCaP, and PC3 cell lines decreased cell viability at concentrations above 2 µM. Moreover, Nithipatikom et al 43 showed a decrease in PC3 cellular proliferation at concentrations above 1 µM, but caused an increase in cellular proliferation with the cannabinoid 2-AG at similar concentrations. ...
Article
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The efficacy of chemotherapy depends on the tumor microenvironment. This microenvironment consists of a complex cellular network that can exert both stimulatory and inhibitory effects on tumor genesis. Given the increasing interest in the effectiveness of cannabis, cannabinoids have gained much attention as a potential chemotherapy drug. Cannabinoids are a group of marker compounds found in Cannabis sativa L., more commonly known as marijuana, a psychoactive drug used since ancient times for pain management. Although the anticancer potential of C. sativa, has been recognized previously, increased attention was generated after discovering the endocannabinoid system and the successful production of cannabinoid receptors. In vitro and in vivo studies on various tumor models have shown therapeutic efficiency by modifying the tumor microenvironment. However, despite extensive attention regarding potential therapeutic implications of cannabinoids, considerable clinical and preclinical analysis is needed to adequately define the physiological, pharmacological, and medicinal aspects of this range of compounds in various disorders covered in this review. This review summarizes the key literature surrounding the role of cannabinoids in the tumor microenvironment and their future promise in cancer treatment.
... Numerous reports have shown that the modulation of CBR activity by cannabinoids inhibits the in vitro and in vivo growth and survival of cancer cells via the production of ceramide, a pro-apoptotic sphingolipid [49,69,[118][119][120]. CBR activation by either ∆ 9 -THC or WIN-55,212-2 drives the intracellular accumulation of ceramide to activate Raf1/ERK signalling, which in turn leads to the production of damaging cellular reactive oxygen species (ROS) (Figures 2 and 3). ...
Article
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Cannabis has been used to relieve the symptoms of disease for thousands of years. However, social and political biases have limited effective interrogation of the potential benefits of cannabis and polarised public opinion. Further, the medicinal and clinical utility of cannabis is limited by the psychotropic side effects of ∆9-tetrahydrocannabinol (∆9-THC). Evidence is emerging for the therapeutic benefits of cannabis in the treatment of neurological and neurodegenerative diseases, with potential efficacy as an analgesic and antiemetic for the management of cancer-related pain and treatment-related nausea and vomiting, respectively. An increasing number of preclinical studies have established that ∆9-THC can inhibit the growth and proliferation of cancerous cells through the modulation of cannabinoid receptors (CB1R and CB2R), but clinical confirmation remains lacking. In parallel, the anti-cancer properties of non-THC cannabinoids, such as cannabidiol (CBD), are linked to the modulation of non-CB1R/CB2R G-protein-coupled receptors, neurotransmitter receptors, and ligand-regulated transcription factors, which together modulate oncogenic signalling and redox homeostasis. Additional evidence has also demonstrated the anti-inflammatory properties of cannabinoids, and this may prove relevant in the context of peritumoural oedema and the tumour immune microenvironment. This review aims to document the emerging mechanisms of anti-cancer actions of non-THC cannabinoids.
... Patsos et al. [88] revealed that PG-EAs, the cyclooxygenase 2 (COX-2) dependent metabolites of anandamide, induced apoptosis of colorectal cancer cells, while anandamide stimulated non-apoptotic cell death in COX-2 overexpressed colorectal cancer cells. In EGFR-overexpressed prostate cancer cells, anandamide decreased EGFR levels by interacting with cannabinoid CB1 receptor, and consequently, inhibited the cancer cell proliferation [89]. ...
Article
Full-text available
Truffles, the symbiotic hypogeous edible fungi, have been worldwide regarded as a great delicacy because of their unique flavor and high nutritional value. By identifying their bioactive components such as phenolics, terpenoids, polysaccharides, anandamide, fatty acids, and ergosterols, researchers have paid attention to their biological activi- ties including antitumor, antioxidant, antibacterial, anti-inflammatory, and hepatoprotective activities. In addition, numerous factors have been investigating that can affect the quality and productivity of truffles to overcome their difficulty in culturing and preserving. To provide the information for their potential applications in medicine as well as in functional food, this review summarizes the relevant literature about the biochemical composition, aromatic and nutritional benefits, and biological properties of truffles. Besides, various factors affecting their productivity and qual- ity as well as the preservation methods are also highlighted.
... In Cannabinoid Receptor Agonist-induced Apoptosis of Human Prostate Cancer Cells LNCaP Proceeds through Sustained Activation of ERK1/2 Leading to G 1 Cell Cycle Arrest (Sarfaraz et al. 2006), we read: "Based on these data we suggest that cannabinoid receptor agonists should be considered as novel agents for the management of prostate cancer." In Anti-proliferative and apoptotic effects of anandamide in human prostatic cancer cell lines: implication of epidermal growth factor receptor down-regulation and ceramide production (Mimeault et al. 2003), we read: "The potent anti-proliferative and cytotoxic effects of ANA on metastatic prostatic cancer cells might provide basis for the design of new therapeutic agents for effective treatment of recurrent and invasive prostatic cancers." In Endocannabinoids in endocrine and related tumours (Bifulco et al. 2008), we read: "Accumulated evidence indicates that CBs could be an important target for the treatment of cancer due to their ability to regulate signalling pathways critical for cell growth and survival. ...
... Sundry's studies have evidenced the anti-proliferative activity of cannabinoids in prostate tumours. Anandamide inhibits the Cancers 2020, 12, 3275 9 of 21 proliferation of cells (PC-3, DU-145, and LNCaP) [98,99] and primary cultures of PC [91] via CB1R. Phytocannabinoids also reduce PC cell proliferation. ...
Article
Full-text available
The various components of the endocannabinoid system (ECS), such as the cannabinoid receptors (CBRs), cannabinoid ligands, and the signalling network behind it, are implicated in several tumour-related states, both as favourable and unfavourable factors. This review analyses the ECS’s complex involvement in the susceptibility to cancer, prognosis, and response to treatment, focusing on its relationship with cancer biology in selected solid cancers (breast, gastrointestinal, gynaecological, prostate cancer, thoracic, thyroid, CNS tumours, and melanoma). Changes in the expression and activation of CBRs, as well as their ability to form distinct functional heteromers affect the cell’s tumourigenic potential and their signalling properties, leading to pharmacologically different outcomes. Thus, the same ECS component can exert both protective and pathogenic effects in different tumour subtypes, which are often pathologically driven by different biological factors. The use of endogenous and exogenous cannabinoids as anti-cancer agents, and the range of effects they might induce (cell death, regulation of angiogenesis, and invasion or anticancer immunity), depend in great deal on the tumour type and the specific ECS component that they target. Although an attractive target, the use of ECS components in anti-cancer treatment is still interlinked with many legal and ethical issues that need to be considered.
... Although the authors observed a dose-dependent decrease in cell proliferation in all the three cell lines (DU145, PC3 and LNCaP), the potential of AEA was found to considerably vary between the cells. While in DU145 and PC3, a concentration of 5 μM of AEA was able to completely inhibit EGF induced cell growth, in LNCaP cell line, only a 30% reduction in cell growth was observed at this concentration (Mimeault et al., 2003). These observations can be a result of the distinct nature of cell lines or of a cell line dependent variation in AEA metabolism (Endsley et al., 2008;Ruiz-Llorente et al., 2004). ...
Article
Derivatives of the plant Cannabis sativa have been used for centuries for both medical and recreational purposes, as well as industrial. The first proof of its medicinal use comes from ancient China, although there is evidence of its earlier utilization in Europe and Asia. In the 19th century, European practitioners started to employ cannabis extracts to treat tetanus, convulsions, and mental diseases and, in 1851, cannabis made its appearance in the Pharmacopoeia of the United States as an analgesic, hypnotic and anticonvulsant. It was only in 1937 that the Marijuana Tax Act prohibited the use of this drug in the USA. The general term Cannabis is commonly used by the scientific and scholar community to indicate derivatives of the plant Cannabis sativa. The word cannabinoid is a term describing chemical compounds that are either derivate of Cannabis (phytocannabinoids) or artificial analogues (synthetic) or are produced endogenously by the body (endocannabinoids). A more casual term “marijuana” or “weed”, a compound derived from dried Cannabis flower tops and leaves, has progressively superseded the term cannabis when referred to its recreational use. The 2018 World health organisation (WHO) data suggest that nearly 2.5% of the global population (147 million) uses marijuana and some countries, such as Canada and Uruguay, have already legalised it. Due to its controversial history, the medicinal use of cannabinoids has always been a centre of debate. The isolation and characterisation of Δ⁹ tetrahydrocannabinol (THC), the major psychoactive component of cannabis and the detection of two human cannabinoid receptor (CBRs) molecules renewed interest in the medical use of cannabinoids, boosting research and commercial heed in this sector. Some cannabinoid-based drugs have been approved as medications, mainly as antiemetic, antianorexic, anti-seizure remedies and in cancer and multiple sclerosis patients' palliative care. Nevertheless, due to the stigma commonly associated with these compounds, cannabinoids’ potential in the treatment of conditions such as cancer is still largely unknown and therefore underestimated.
... Et il semble que cela soit le cas: on aura remarqué un 48 phénomène d'apoptose aussi dans le cancer du sein lors de prise de cannabidiol, d'une mort cellulaire dans des cultures de cellules de cancer de la prostate misent en présence de cannabigérol... Il a été rapporté que l'anandamide endogène possède une action antiprolifératrice. (44) Les cannabinoïdes participent aussi à la lutte contre l'inflammation, ce qui peut du coup freiner le développement des cancers lorsque l'on sait que 15 à 20% des décès par cancer dans le monde sont liés à la réponse inflammatoire de l'organisme atteint. (45) Cependant ces résultats doivent être nuancés car les mécanismes d'actions prouvés et mis en évidence ont été réalisés dans un cadre bien précis avec une facilité d'apport du traitement aux cellules: en effet les cannabinoïdes étaient injectés directement dans les tumeurs d'animaux vivants ou dans des cancers créés de manière artificielle. ...
Thesis
Le cannabis est un sujet d'actualité. Des groupes de personnes de sensibilité parfois différentes remettentrégulièrement sur le devant de la scène ce sujet de société toujours brûlant à traiter. Que l'on soit solidaire dupour ou du contre, le sujet mérite que l'on s'y intéresse et que l'on se pose des questions pour essayerd'éclairer un peu le problème.Dans cette démarche, nous nous intéresserons à comprendre ce qu'est le cannabis. Nous le définirons afin demieux le connaître, nous verrons ses utilisations, ses mésusages, ses effets (toxiques ou thérapeutiques),...Nous parlerons aussi de législation afin de voir les différentes réponses apportées par la France et d'autrespays par rapport au cannabis drogue et au cannabis médicament, nous tenterons d'ailleurs dans ce travail demontrer la limite entre les deux mondes si limite il y a... Rappelant au passage que le mot "drogue" convientpour définir une substance active d'origine naturelle non transformée qui présente une activitémédicamenteuse selon la définition donnée par l'académie nationale de pharmacie.
... CB1 and/or CB2 receptors are coupled to several signaling pathways directly involved in cell survival, proliferation, and apoptosis, including p38 MAPK, cyclic AMP, PI3K-Akt, RhoA, JNK, EGFR, ERK, 24 and ceramide pathways. 1,19,[25][26][27][28][29][30] Ceramide seems to be the key mediator of cannabinoidmediated anticancer effects. Cannabinoids induce sustained production of sphingolipid ceramide, which is commonly found in the cell membrane and is generated de novo by ceramide synthase or through sphingomyelin hydrolysis. ...
Article
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The endocannabinoid system (ECS) comprises cannabinoid receptors (CBs), endogenous cannabinoids, and enzymes responsible for their synthesis, transport, and degradation of (endo)cannabinoids. To date, two CBs, CB1 and CB2, have been characterized; however, orphan G-protein-coupled receptor GPR55 has been suggested to be the third putative CB. Several different types of cancer present abnormal expression of CBs, as well as other components of ECS, and this has been shown to correlate with the clinical outcome. Although most effects of (endo)cannabinoids are mediated through stimulation of classical CBs, they also interact with several molecules, either prosurvival or proapoptotic molecules. It should be noted that the mode of action of exogenous cannabinoids differs significantly from that of endocannabinoid and results from the studies on their activity both in vivo and in vitro could not be easily compared. This review highlights the main signaling pathways involved in the antitumor activity of cannabinoids and the influence of their activation on cancer cell biology. We also discuss changes in the expression pattern of the ECS in various cancer types that have an impact on disease progression and patient survival. A growing amount of experimental data imply possible exploitation of cannabinoids in cancer therapy.
... An elevated level of CB-1 and CB-2 were observed in prostate tissues and a variety of cells lines: DU-145, LNCaP, PC-3, and CWR22Rv1 [118,119]. Cannabinoid agonist, JWH-015, stimulated ceramide release through de novo synthesis that triggered cell death following inhibition of the Akt pathway while activating the JNK pathway [120]. Anamide, a psychoactive agonist of cannabis, promoted the antitumor efficacy via accumulation of ceramide with downregulation of epidermal growth factor receptor (EGFR). ...
Article
Various preclinical and clinical studies exhibited the potential of cannabis against various diseases, including cancer and related pain. Subsequently, many efforts have been made to establish and develop cannabis-related products and make them available as prescription products. Moreover, FDA has already approved some cannabis-related products, and more advancement in this aspect is still going on. However, the approved product of cannabis is in oral dosage form, which exerts various limitations to achieve maximum therapeutic effects. A considerable translation is on a hike to improve bioavailability, and ultimately, the therapeutic efficacy of cannabis by the employment of nanotechnology. Besides the well-known psychotropic effects of cannabis upon the use at high doses, literature has also shown the importance of cannabis and its constituents in minimizing the lethality of cancer in the preclinical models. This review discusses the history of cannabis, its legal aspect, safety profile, the mechanism by which cannabis combats with cancer, and the advancement of clinical therapy by exploiting nanotechnology. A brief discussion related to the role of cannabinoid in various cancers has also been incorporated. Lastly, the information regarding completed and ongoing trials have also been elaborated.
... Activation of PPARγ suppresses nuclear factor-κB (NF-κB), which is constitutively active in cancer cells and is responsible for cancer cell proliferation and the formation of inflammatory cytokines such as tumour necrosis factor (TNF)-α. In addition, overall effects are further influenced by endocannabinoids (anandamide, 2-arachidonoylglycerol), which demonstrate anticancer activities of their own [96][97][98][99][100]. Anandamide and 2-arachidonoylglycerol bind to both receptors (CB1 and CB2; anandamide more to CB1 than CB2, and 2-arachidonoylglycerol more to CB2 than CB1). ...
Article
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Preclinical models provided ample evidence that cannabinoids are cytotoxic against cancer cells. Among the best studied phytocannabinoids, cannabidiol (CBD) is most promising for the treatment of cancer as it lacks the psychotomimetic properties of delta-9-tetrahydrocannabinol (THC). In vitro studies and animal experiments point to a concentration- (dose-)dependent anticancer effect. The effectiveness of pure compounds versus extracts is the subject of an ongoing debate. Actual results demonstrate that CBD-rich hemp extracts must be distinguished from THC-rich cannabis preparations. Whereas pure CBD was superior to CBD-rich extracts in most in vitro experiments, the opposite was observed for pure THC and THC-rich extracts, although exceptions were noted. The cytotoxic effects of CBD, THC and extracts seem to depend not only on the nature of cannabinoids and the presence of other phytochemicals but also largely on the nature of cell lines and test conditions. Neither CBD nor THC are universally efficacious in reducing cancer cell viability. The combination of pure cannabinoids may have advantages over single agents, although the optimal ratio seems to depend on the nature of cancer cells; the existence of a 'one size fits all' ratio is very unlikely. As cannabinoids interfere with the endocannabinoid system (ECS), a better understanding of the circadian rhythmicity of the ECS, particularly endocannabinoids and receptors, as well as of the rhythmicity of biological processes related to the growth of cancer cells, could enhance the efficacy of a therapy with cannabinoids by optimization of the timing of the administration, as has already been reported for some of the canonical chemotherapeutics. Theoretically, a CBD dose administered at noon could increase the peak of anandamide and therefore the effects triggered by this agent. Despite the abundance of preclinical articles published over the last 2 decades, well-designed controlled clinical trials on CBD in cancer are still missing. The number of observations in cancer patients, paired with the anticancer activity repeatedly reported in preclinical in vitro and in vivo studies warrants serious scientific exploration moving forward.
... Induction of G0/G1 cell cycle arrest and apoptosis Reduction in cell proliferation through activation of Wnt5a non-canonical pathway Inhibition of cell proliferation induced by FAS-death receptor translocation in lipid rafts, mediated by GPR55 activation [99,190,191] Lung cancer Reduction in tumour cell spreading, mimicking the anti-invasive action of FAAH inhibitors (same effect given by 2-AG, OEA, PEA) [163] Breast cancer Inhibition of cell proliferation through downregulation of adenylate cyclase and activation of MAPK, exerting downregulation on prolactin and tyrosine kinase levels [192][193][194] Prostate cancer Reduction in EGF-induced cell proliferation, induction of apoptosis and necrosis through EGFR downregulation Induction of apoptosis mediated by activation of ERK and inhibition of AKT signalling pathways (same effect given by 2-AG and Met-F-AEA) [195,196] Non-melanoma skin cancer Induction of apoptosis mediated by oxidative stress and CBR-independent signalling [197] Lymphoma Reduction of tumour cell viability [198] R(+)-Methanandamide (stable AEA analogue) ...
Article
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The tumour microenvironment (TME) is now recognised as a hallmark of cancer, since tumour:stroma crosstalk supports the key steps of tumour growth and progression. The dynamic co-evolution of the tumour and stromal compartments may alter the surrounding microenvironment, including the composition in metabolites and signalling mediators. A growing number of evidence reports the involvement of the endocannabinoid system (ECS) in cancer. ECS is composed by a complex network of ligands, receptors, and enzymes, which act in synergy and contribute to several physiological but also pathological processes. Several in vitro and in vivo evidence show that ECS deregulation in cancer cells affects proliferation, migration, invasion, apoptosis, and metastatic potential. Although it is still an evolving research, recent experimental evidence also suggests that ECS can modulate the functional behaviour of several components of the TME, above all the immune cells, endothelial cells and stromal components. However, the role of ECS in the tumour:stroma interplay remains unclear and research in this area is particularly intriguing. This review aims to shed light on the latest relevant findings of the tumour response to ECS modulation, encouraging a more in-depth analysis in this field. Novel discoveries could be promising for novel anti-tumour approaches, targeting the microenvironmental components and the supportive tumour:stroma crosstalk, thereby hindering tumour development.
... In PCa, ceramide induces apoptosis (20), and various molecules may upregulate ceramide in prostate tumor cells (21,22). Ceramide is a component of a three-lipid signature (ceramide, sphingomyelin, and phosphatidylcholine) associated with poor prognosis in castration-resistant PCa (23). ...
Article
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Reliable liquid biopsy-based tools able to accurately discriminate prostate cancer (PCa) from benign prostatic hyperplasia (BPH), when PSA is within the “gray zone” (PSA 4–10), are still urgent. We analyzed plasma samples from a cohort of 102 consecutively recruited patients with PSA levels between 4 and 16 ng/ml, using the SANIST-Cloud Ion Mobility Metabolomic Mass Spectrometry platform, combined with the analysis of a panel of circulating microRNAs (miR). By coupling CIMS ion mobility technology with SANIST, we were able to reveal three new structures among the most differentially expressed metabolites in PCa vs. BPH. In particular, two were classified as polyunsaturated ceramide ester-like and one as polysaturated glycerol ester-like. Penalized logistic regression was applied to build a model to predict PCa, using six circulating miR, seven circulating metabolites, and demographic/clinical variables, as covariates. Four circulating metabolites, miR-5100, and age were selected by the model, and the corresponding prediction score gave an AUC of 0.76 (C.I. = 0.66–0.85). At a specified cut-off, no high-risk tumor was misclassified, and 22 out of 53 BPH were correctly identified, reducing by 40% the false positives of PSA. We developed and applied a novel, minimally invasive, liquid biopsy-based powerful tool to characterize novel metabolites and identified new potential non-invasive biomarkers to better predict PCa, when PSA is uninformative as a tool for precision medicine in genitourinary cancers.
... In addition, cannabinoids are capable of inducing cell apoptosis [22]. Therefore, cannabinoids act as potent anticancer agents against various cancer cell lines such as lymphomas, gliomas, lung cancer, thyroid epithelioma, breast cancer colon cancers and prostate cancers [27][28][29][30][31][32][33]. Cannabis formulations or combination extracts have been considered by many as more effective than the use of individual cannabinoids, with the reason behind this being the "entourage effect" [34,35]. ...
Article
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The development of a protocol for the large-scale production of Cannabis and its variants with little to no somaclonal variation or disease for pharmaceutical and for other industrial use has been an emerging area of research. A limited number of protocols have been developed around the world, obtained through a detailed literature search using web-based database searches, e.g., Scopus, Web of Science (WoS) and Google Scholar. This article reviews the advances made in relation to Cannabis tissue culture and micropropagation, such as explant choice and decontamination of explants, direct and indirect organogenesis, rooting, acclimatisation and a few aspects of genetic engineering. Since Cannabis micropropagation systems are fairly new fields, combinations of plant growth regulator experiments are needed to gain insight into the development of direct and indirect organogenesis protocols that are able to undergo the acclimation stage and maintain healthy plants desirable to the Cannabis industry. A post-culture analysis of Cannabis phytochemistry after the acclimatisation stage is lacking in a majority of the reviewed studies, and for in vitro propagation protocols to be accepted by the pharmaceutical industries, phytochemical and possibly pharmacological research need to be undertaken in order to ascertain the integrity of the generated plant material. It is rather difficult to obtain industrially acceptable micropropagation regimes as recalcitrance to the regeneration of in vitro cultured plants remains a major concern and this impedes progress in the application of genetic modification technologies and gene editing tools to be used routinely for the improvement of Cannabis genotypes that are used in various industries globally. In the future, with more reliable plant tissue culture-based propagation that generates true-to-type plants that have known genetic and metabolomic integrity, the use of genetic engineering systems including “omics” technologies such as next-generation sequencing and fast-evolving gene editing tools could be implemented to speed up the identification of novel genes and mechanisms involved in the biosynthesis of Cannabis phytochemicals for large-scale production.
... Numerous studies refer to the antiproliferative effects of several endocannabinoids in prostate cancer cells. It has been shown that AEA inhibits PC-3 cells proliferation [87], and the proliferation of DU-145, PC-3, and LNCaP prostate cancer cells induced by EGF, blocking cell cycle at G 1 phase, and downregulating EGF receptor [88]. Orellana-Serradell et al. also reported the growth inhibitory effect of AEA, and 2-AG, not only in PC-3 cell line, but also in primary cultures of prostate cancer, triggering apoptosis [53]. ...
Article
Introduction: The term "cannabinoids" designates a family of compounds with activity upon cannabinoid receptors. Cannabinoids are classified in three groups: phytocannabinoids, endocannabinoids, and the synthetic analogues of both groups. They have become a promising tool in the treatment of cancer disease, not only as palliative agents, but also as antitumor drugs, due to their ability to inhibit the proliferation, adhesion, migration, invasion, and angiogenesis of tumour cells. Two of the cancers where they have shown high anticancer activity are breast and prostate tumours. Despite this potential clinical interest, several studies have also reported that cannabinoids can stimulate the proliferation of cancer cells at very low concentrations. Areas covered: The aim of this review is to evaluate the promising chemotherapeutic utility of phytocannabinoids, endocannabinoids, and synthetic cannabinoids in breast and prostate cancer. Expert opinion: Cannabinoids, in particular the non-psychoactive CBD, may be promising tools in combination therapy for breast and prostate cancer, due to their direct antitumor effects, their ability to improve the efficacy of conventional antitumor drugs and their usefulness as palliative treatment. Nevertheless, deeper studies to fully establish the mechanisms responsible for their antitumour and pro-tumour properties and their formulation in efficient delivery systems remain to be established.
... CB1 receptor expression upregulation has been observed in prostate cancer tissues [204] and elevated levels of this receptor are associated with cancer severity and outcome [203]. Accordingly, AEA has been found to exhibit antiproliferative effects in LNCaP, DU145, and PC3 prostate cancer cells by acting through cannabinoid CB1 receptor and this led to an inhibition of the EGF-stimulated growth of these cells [201]. However recent studies documented that the cannabinoids CBD was able to reduce androgen receptor (AR)-positive (LNCaP and 22RV1) and AR-negative (DU-145 and PC-3) cells in a CB receptors independent manner [202], suggesting that CB1 receptor could be the main cannabinoid receptor that regulates the complex carcinogenic steps leading to prostate cancer. ...
Article
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The endocannabinoid system (ECS) is a lipid cell signaling system involved in the physiology and homeostasis of the brain and peripheral tissues. Synaptic plasticity, neuroendocrine functions, reproduction, and immune response among others all require the activity of functional ECS, with the onset of disease in case of ECS impairment. Estrogens, classically considered as female steroid hormones, regulate growth, differentiation, and many other functions in a broad range of target tissues and both sexes through the activation of nuclear and membrane estrogen receptors (ERs), which leads to genomic and non-genomic cell responses. Since ECS function overlaps or integrates with many other cell signaling systems, this review aims at updating the knowledge about the possible crosstalk between ECS and estrogen system (ES) at both central and peripheral level, with focuses on the central nervous system, reproduction, and cancer.
... Anandamide downregulated the expression of prolactin receptors, brca1 gene products, trk proteins and neurotrophin receptors. This involved the inhibition of cAMP-kinase A pathway and the activation of MAPK, prevented the phosphorylation of Raf by protein kinase A and activated the RAF1-MEK-ERK signalling cascade [112,113]. In DU145 and PC3 (androgenin dependent), and LNCaP (androgen-stimulated) human prostate cancer cells, it downregulated the EGF-R level, arrested the G1 phase, and thereby, inhibiting their proliferation. ...
Article
Cannabinoids are the major chemical constituents of the plant Cannabis sativa L. and are known to exhibit a wide range of pharmacological effects viz., psychotropic, analgesic, anticancer, antiinflammatory, antidiabetic, anticonvulsive, antibacterial and antifungal etc. The use of cannabis, cannabinoids and their products is restricted in several countries due to the high risk of misuse. Recently, cannabinoids have regained the interest of the researchers due to their therapeutic applications. Ever since the discovery of the cannabinoids, most of the studies carried out on the evaluation of their biological activities were limited to only preclinical levels. The quality of the preclinical data still remains only low to moderate, thus, leaving behind an uncertainty in their use for therapeutic applications. Problems associated with the solubility, stability and bioavailability of the cannabinoid drugs are also a major concern in the quality of the study. Nanoparticle based drug delivery system could be a potential method to increase the reliability of the data. While considering the immense pharmacological properties of the cannabinoids, there is an urgency to perform intensive clinical trials and to know their mechanism of action in various disease conditions, evaluate their efficacy and safety, and register them as drug candidates. This review highlights the chemistry, types and biological activities of the cannabinoids such as THC, CBD and CBN in focus with their anticancer activity, neuroprotective effect and nanoformulating the cannabinoid drugs.
... In Cannabinoid Receptor Agonist-induced Apoptosis of Human Prostate Cancer Cells LNCaP Proceeds through Sustained Activation of ERK1/2 Leading to G 1 Cell Cycle Arrest (Sarfaraz et al. 2006), we read: "Based on these data we suggest that cannabinoid receptor agonists should be considered as novel agents for the management of prostate cancer." In Anti-proliferative and apoptotic effects of anandamide in human prostatic cancer cell lines: implication of epidermal growth factor receptor down-regulation and ceramide production (Mimeault et al. 2003), we read: "The potent anti-proliferative and cytotoxic effects of ANA on metastatic prostatic cancer cells might provide basis for the design of new therapeutic agents for effective treatment of recurrent and invasive prostatic cancers." In Endocannabinoids in endocrine and related tumours (Bifulco et al. 2008), we read: "Accumulated evidence indicates that CBs could be an important target for the treatment of cancer due to their ability to regulate signalling pathways critical for cell growth and survival. ...
Book
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Cannabis Sativa has been used for medicinal and other purposes for millennia. In the 1990s the CB1 and CB2 receptors and the endogenous ligands of the endo-cannabinoid system proper were discovered: Anandamide N-arachidonoylethanolamine (AEA) and 2-Arachidonoylglycerol (2-AG). External mediation of the bodily endo-cannabinoid system with exogenous phytochemical cannabinoids and other active compounds within Cannabis representative of the full interactive proliferation of naturally occurring constituents appears from manifest interdigitated cross-mediational systemic complexity and phylogenetic receptor analysis to imply the likelihood of potential synergistic therapeutic efficacy via evolutionary adaptations beginning from as far back as the Cambrian period or more. This approach utilizing the full proliferation of interactive compounds or some selected intra-active multi-constituent portion thereof, has been demonstrably curtailed by legal, political and systemic interference. This document will spell out the demonstrated functional potential and implied therapeutic utility of cannabinoids and cannabis extracts, support the aforementioned evolutionary hypothesis and demonstrated multifunctional medical utility with both phylogenetic and historical analysis, and then detail what appears to be the suppressed approach that may lead to the speedy and inexpensive treatment or cure of many dread diseases using Cannabis extracts, including but not limited to cancer. It is also clearly implied and well supported from historical and current medical perspectives that the raw drug itself is safe and effective in treating many conditions and should be available to dispense via prescription by all qualified medical professionals.
... Sundry studies have evidenced the anti-proliferative activity of cannabinoids in prostate tumours. Anandamide inhibits the proliferation of cells (PC-3, DU-145 and LNCaP) [240,241] and primary cultures of prostate carcinoma [237] via CB 1 receptors. However, the anti-proliferative activity of CBD and Δ 9 -THC does not involve cannabinoid receptors. ...
Article
Cannabinoid receptors, endocannabinoids and the enzymes responsible for their biosynthesis and degradation constitute the endocannabinoid system. In recent decades, the endocannabinoid system has attracted considerable interest as a potential therapeutic target in numerous pathological conditions. Its involvement in several physiological processes is well known, such as in energy balance, appetite stimulation, blood pressure, pain modulation, embryogenesis, nausea and vomiting control, memory, learning and immune response, among others, as well as in pathological conditions where it exerts a protective role in the development of certain disorders. As a result, it has been reported that changes in endocannabinoid levels may be related to neurological diseases such as Parkinson’s disease, Huntington’s disease, Alzheimer’s disease and multiple sclerosis, as well as anorexia and irritable bowel syndrome. Alterations in the endocannabinoid system have also been associated with cancer, affecting the growth, migration and invasion of some tumours. Cannabinoids have been tested in several cancer types, including brain, breast and prostate cancers. Cannabinoids have shown promise as analgesics for the treatment of both inflammatory and neuropathic pain. There is also evidence for a role of the endocannabinoid system in the control of emotional states, and cannabinoids could prove useful in decreasing and palliating post-traumatic stress disorder symptoms and anxiolytic disorders. The role of the endocannabinoid system in addictions has also been examined, and cannabinoids have been postulated as alternative and co-adjuvant treatments in some abuse syndromes, mainly in ethanol and opioid abuses. The expression of the endocannabinoid system in the eye suggests that it could be a potential therapeutic target for eye diseases. Considering the importance of the endocannabinoid system and the therapeutic potential of cannabinoids in this vast number of medical conditions, several clinical studies with cannabinoid-based medications are ongoing. In addition, some cannabinoid-based medications have already been approved in various countries, including nabilone and dronabinol capsules for the treatment of nausea and vomiting associated with chemotherapy, dronabinol capsules for anorexia, an oral solution of dronabinol for both vomiting associated with chemotherapy and anorexia, a Δ⁹-tetrahydrocannabinol/cannabidiol oromucosal spray for pain related to cancer and for spasticity and pain associated with multiple sclerosis, and an oral solution of cannabidiol for Dravet and Lennox–Gastaut syndromes. Here, we review the available efficacy, safety and tolerability data for cannabinoids in a range of medical conditions.
Article
The physiological and pathophysiological roles of sex hormones have been well documented and the modulation of their effects is applicable in many current treatments. On the other hand, the physiological role of endocannabinoids is not yet clearly understood and the endocannabinoid system is considered a relatively new therapeutic target. The physiological association between sex hormones and cannabinoids has been investigated in several studies; however, its involvement in the pathophysiology of common human diseases has been studied separately. Herein, we present the first systematic review of molecular pathways that are influenced by both the cannabinoids and sex hormones, including adenylate cyclase and protein kinase A, epidermal growth factor receptor, cyclic adenosine monophosphate response element-binding protein, vascular endothelial growth factor, proto-oncogene serine/threonine-protein kinase, mitogen-activated protein kinase, phosphatidylinositol-4,5-bisphosphate 3-kinase, C-Jun N-terminal kinase and extracellular-signal-regulated kinases 1/2. Most of these influence cell proliferative activity. Better insight into this association may prove to be beneficial for the development of novel pharmacological treatment strategies for many common diseases, including breast cancer, endometrial cancer, prostate cancer, osteoporosis and atherosclerosis. The associations between cannabinoids, estrogens and androgens under these conditions are also presented and the molecular interactions are highlighted.
Article
The endocannabinoid system is a signaling system involved in a wide range of biological effects. Literature strongly suggests the endocannabinoid system role in the pathogenesis of cancer and that its pharmacological activation produces therapeutic benefits. Last research promotes the endocannabinoid system modulation by inhibition of endocannabinoids hydrolytic enzymes instead of direct activation of endocannabinoid receptors to avoid detrimental effects on cognition and motor control. Here we report the identification of N-acylethanolamine-hydrolyzing acid amidase (NAAA) inhibitors able to reduce cell proliferation and migration and cause cell death on different bladder cancer cell lines. These molecules were designed, synthesized and characterized and active compounds were selected by a fluorescence high-throughput screening method set-up on human recombinant NAAA that also allows to characterize the mechanism of inhibition. Together our results suggest an important role for NAAA in cell migration and in inducing tumor cell death promoting this enzyme as pharmacological target against bladder cancer.
Article
The endocannabinoid system is currently under intense investigation due to the therapeutic potential of cannabinoid-based drugs as treatment options for a broad variety of diseases including cancer. Besides the canonical endocannabinoid system that includes the cannabinoid receptors CB1 and CB2 and the endocannabinoids N-arachidonoylethanolamine (anandamide) and 2-arachidonoylglycerol, recent investigations suggest that other fatty acid derivatives, receptors, enzymes, and lipid transporters likewise orchestrate this system as components of the endocannabinoid system when defined as an extended signaling network. As such, fatty acids acting at cannabinoid receptors (e.g. 2-arachidonoyl glyceryl ether [noladin ether], N-arachidonoyldopamine) as well as endocannabinoid-like substances that do not elicit cannabinoid receptor activation (e.g. N-palmitoylethanolamine, N-oleoylethanolamine) have raised interest as anticancerogenic substances. Furthermore, the endocannabinoid-degrading enzymes fatty acid amide hydrolase and monoacylglycerol lipase, lipid transport proteins of the fatty acid binding protein family, additional cannabinoid-activated G protein-coupled receptors, members of the transient receptor potential family as well as peroxisome proliferator-activated receptors have been considered as targets of antitumoral cannabinoid activity. Therefore, this review focused on the antitumorigenic effects induced upon modulation of this extended endocannabinoid network.
Article
There are several alternatives for treating malign neoplastic growths in dogs, including chemotherapy; however, traditionally used drugs have high levels of toxicity due to their low selectivity regarding cancer cells. These compounds' main adverse effects involve gastrointestinal disorders, bone marrow suppression (myelotoxicity), behavioral alterations, alopecia and carcinogenic potential. Research groups around the world are currently working on developing new drugs from cannabinoids and/or endocannabinoids-derived molecules, based on tetrahydrocannabinol and anandamide's known anti-neoplastic activity. Trials reported to date have led to concluding that such compounds offer greater selectivity regarding action on unhealthy cells, thereby representing a lower range of toxic risks. It has been shown that pharmacological treatment regarding any disease should adhere to biological rhythms to obtain a better therapeutic response and incur fewer collateral effects. This article was thus aimed at ascertaining the benefits of future antineoplastic treatment inspired by the behavior of cannabinoids and endocannabinoids in the evolution of neoplastic diseases.
Chapter
The endocannabinoid system encompassing cannabinoid receptors, endogenous receptor ligands (endocannabinoids), as well as enzymes conferring the synthesis and degradation of endocannabinoids has emerged as a considerable target for pharmacotherapeutical approaches of numerous diseases. Besides palliative effects of cannabinoids used in cancer treatment, phytocannabinoids, synthetic agonists, as well as substances that increase endogenous endocannabinoid levels have gained interest as potential agents for systemic cancer treatment. Accordingly, cannabinoid compounds have been reported to inhibit tumor growth and spreading in numerous rodent models. The underlying mechanisms include induction of apoptosis, autophagy, and cell cycle arrest in tumor cells as well as inhibition of tumor cell invasion and angiogenic features of endothelial cells. In addition, cannabinoids have been shown to suppress epithelial-to-mesenchymal transition, to enhance tumor immune surveillance, and to support chemotherapeutics’ effects on drug-resistant cancer cells. However, unwanted side effects include psychoactivity and possibly pathogenic effects on liver health. Other cannabinoids such as the nonpsychoactive cannabidiol exert a comparatively good safety profile while exhibiting considerable anticancer properties. So far experience with anticarcinogenic effects of cannabinoids is confined to in vitro studies and animal models. Although a bench-to-bedside conversion remains to be established, the current knowledge suggests cannabinoid compounds to serve as a group of drugs that may offer significant advantages for patients suffering from cancer diseases. The present review summarizes the role of the endocannabinoid system and cannabinoid compounds in tumor progression.
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Background: Cannabis has a very extensive history of its uses as a medicinal plant that likely dates back more than two millennia. This review was envisioned to provide a brief summary on ethnobotany, phytochemistry, medicinal uses and some biological activities of Cannabis (hemp) with emphasis on its legalization and regulation in Pakistan. Methods: The data on Cannabis was assembled from International scientific databases like Google Scholar, PubMed/Medline, Researchgate, SciELO, Scopus, Science Direct, Taylor and Francis, Web of Science, books, government reports, Master’s and Ph.D. dissertations using specific keywords. Results: In more than 33 different regions of Pakistan, the folk medicinal uses of Cannabis against ~60 ailments are still continuing. Phytochemistry data showed that more than 70 different compounds were reported in Cannabis from Pakistan with potential antioxidant activity. Overall, the antimicrobial activity reviewed here showed that Cannabis extracts against ~19 bacterial and 8 fungal strains possess potential inhibitory effects. Data on anticancer activity of Cannabis worldwide showed remarkable outcomes against more than 12 different cancer types and no data was found on the anticancer activity from Pakistan. Conclusions: Conclusively, essential compounds isolated from Cannabis may exhibit different pharmacological actions and therefore support the utilization of species infusions and/or decoctions as folk traditional medicine in Pakistan. Through the legalization, revenue could be increased by exporting Cannabis based products or by exporting the raw material however, it should be complemented with extensive approaches to publicize the medicinal importance of Cannabis and appropriate policies should be developed for industrial and medicinal use.
Article
In the last decades, the endocannabinoid system has attracted a great interest in medicine and cancer disease is probably one of its most promising therapeutic areas. On the one hand, endocannabinoid system expression has been found altered in numerous types of tumours compared to healthy tissue, and this aberrant expression has been related to cancer prognosis and disease outcome, suggesting a role of this system in tumour growth and progression that depends on cancer type. On the other hand, it has been reported that cannabinoids exert an anticancer activity by inhibiting the proliferation, migration and/or invasion of cancer cells; and also tumour angiogenesis. However, some cannabinoids, at lower concentrations, may increase tumour proliferation, inducing cancer growth. The endocannabinoid system may be considered as a new therapeutic target, although further studies to fully establish the effect of cannabinoids on tumour progression remain necessary.
Chapter
Sphingolipids are bioactive lipids that participate in a wide variety of biological mechanisms, including cell death and proliferation. The myriad of pro-death and pro-survival cellular pathways involving sphingolipids provide a plethora of opportunities for dysregulation in cancers. In recent years, modulation of these sphingolipid metabolic pathways has been in the forefront of drug discovery for cancer therapeutics. About two decades ago, researchers first showed that standard of care treatments, e.g., chemotherapeutics and radiation, modulate sphingolipid metabolism to increase endogenous ceramides, which kill cancer cells. Strikingly, resistance to these treatments has also been linked to altered sphingolipid metabolism, favoring lipid species that ultimately lead to cell survival. To this end, many inhibitors of sphingolipid metabolism have been developed to further define not only our understanding of these pathways but also to potentially serve as therapeutic interventions. Therefore, understanding how to better use these new drugs that target sphingolipid metabolism, either alone or in combination with current cancer treatments, holds great potential for cancer control. While sphingolipids in cancer have been reviewed previously (Hannun & Obeid, 2018; Lee & Kolesnick, 2017; Morad & Cabot, 2013; Newton, Lima, Maceyka, & Spiegel, 2015; Ogretmen, 2018; Ryland, Fox, Liu, Loughran, & Kester, 2011) in this chapter, we present a comprehensive review on how standard of care therapeutics affects sphingolipid metabolism, the current landscape of sphingolipid inhibitors, and the clinical utility of sphingolipid-based cancer therapeutics.
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Prostate cancer is an enigmatic disease. Although prostatic-intraepithelial neoplasia appears as early as the third decade and as many as 80% of 80 year old men have epithelial cells in their prostate that fit the morphological criteria for cancer, only about 10% of men will ever have the clinical disease and less than 3% will die from it. There have been no significant proven interventions which have altered the natural history of the disease since hormone down regulation was introduced in the 1940s and new research has been poorly supported. There is however an urgent need to develop new criteria to distinguish those patients with localised disease who will benefit from intervention from those that do not require it or who will have occult extra prostatic metastases. Similarly, there is an urgent need to develop new treatments for those in whom the disease is extra-prostatic and therefore incurable by conventional treatments. This review covers the latest developments in epidemiology, cellular and molecular biology including new areas such as ion channels in the field of prostate cancer.
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Prostate cancer (PCA) is the most common nonskin malignancy and the second leading cause of cancer deaths in United States males. One practical and translational approach to control PCA is to define a mechanism-based anticarcinogenic agent(s). Recently, we showed that silymarin, a flavonoid antioxidant isolated from milk thistle, possesses exceptionally high to complete protective effects against experimentally induced tumorigenesis. Because the epidermal growth factor receptor (erbB1) and other members of the erbB family have been shown to play important roles in human PCA, efforts should be directed to identify inhibitors of this pathway for PCA intervention. In this study, we assessed whether silymarin inhibits erbB1 activation and associated downstream events and modulates cell cycle regulatory proteins and progression, leading to growth inhibition of human prostate carcinoma DU145 cells. Treatment of serum-starved cells with silymarin resulted in a significant inhibition of transforming growth factor alpha-mediated activation of erbB1 but no change in its protein levels. Silymarin treatment of cells also resulted in a significant decrease in tyrosine phosphorylation of an immediate downstream target of erbB1, the adapter protein SHC, together with a decrease in its binding to erbB1. In the studies analyzing cell cycle regulatory molecules, silymarin treatment of cells also resulted in a significant induction of cyclin-dependent kinase inhibitors (CDKIs) Cip1/p21 and Kip1/p27, concomitant with a significant decrease in CDK4 expression, but no change in the levels of CDK2 and CDK6 and their associated cyclins E and D1, respectively. Cells treated with silymarin also showed an increased binding of CDKIs with CDKs, together with a marked decrease in the kinase activity of CDKs and associated cyclins. In additional studies, treatment of cells grown in 10% serum with anti-epidermal growth factor receptor monoclonal antibody clone 225 or different doses of silymarin also resulted in significant inhibition of constitutive tyrosine phosphorylation of both erbB1 and SHC but no change in their protein levels. Furthermore, whereas silymarin treatment resulted in a significant increase in the protein levels of both Cip1/p21 and Kip1/p27, monoclonal antibody 225 showed an increase only in Kip1/p27. These findings suggest that silymarin also inhibits constitutive activation of erbB1 and that the observed effect of silymarin on an increase in CDKI protein levels is mediated via inhibition of erbB1 activation only in the case of Kip1/p27; however, additional pathways independent of inhibition of erbB1 activation are possibly responsible for the silymarin-caused increase in Cip1/p21 in DU145 cells. In other studies, silymarin treatment also induced a G1 arrest in the cell cycle progression of DU145 cells and resulted in a highly significant to complete inhibition of both anchorage-dependent and anchorage-independent growth of DU145 cells in a dose- and time-dependent manner. Taken together, these results suggest that silymarin may exert a strong anticarcinogenic effect against PCA and that this effect is likely to involve impairment of erbB1-SHC-mediated signaling pathway, induction of CDKIs, and a resultant G1 arrest.
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Expression of the RIalpha subunit of cAMP-dependent protein kinase type I is increased in human cancers in which an autocrine pathway for epidermal growth factor-related growth factors is activated. We have investigated the effect of sequence-specific inhibition of RIalpha gene expression on ovarian cancer cell growth. We report that RIalpha antisense treatment results in a reduction in RIalpha expression and protein kinase A type I, and inhibition of cell growth. The growth inhibition was accompanied by changes in cell morphology and appearance of apoptotic nuclei. In addition, EGF receptor, c-erbB-2 and c-erbB-3 levels were reduced, and the basal and EGF-stimulated mitogen-activated protein kinase activities were reduced. Protein kinase A type I and EGF receptor levels were also reduced in cells overexpressing EGF receptor antisense cDNA. These results suggest that the antisense depletion of RIalpha leads to blockade of both the serine-threonine kinase and the tyrosine kinase signaling pathways resulting in arrest of ovarian cancer cell growth.
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Cell lines derived from human prostate cancer are regarded as relatively resistant to both radiation-induced clonogenic death and apoptosis. Here we attempted to modulate the response of LNCaP prostate cancer cells to radiation therapy (XRT) by pretreatment with 12-O-tetradecanoylphorbol acetate (TPA), a known apoptogenic agent in LNCaP cells. Using plateau-phase cultures, we investigated the response of these cells to XRT, TPA, and a combination of XRT and TPA. LNCaP irradiation did not result in ceramide generation or apoptosis. However, pretreatment with TPA enabled XRT to generate ceramide via activation of the enzyme ceramide synthase and signal apoptosis. Apoptosis was abrogated by the competitive inhibitor of ceramide synthase, fumonisin B1. Furthermore, when transplanted orthotopically into the prostate of nude mice, LNCaP cells produced tumors that recapitulated the responses of LNCaP cells in vitro. XRT or TPA failed to signal apoptosis in LNCaP tumors, whereas a combination of the two resulted in substantial (20-25%) apoptosis within 24 h. There was an additional benefit associated with this regimen because TPA pretreatment protected the adjacent rectum from radiation-induced apoptosis. This represents the first description of signaling-based therapy designed to overcome one form of radiation resistance expressed preferentially in LNCaP human prostate cancer cells.
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Activation of the apoptosis program has been implicated in the response of cancer cells to chemotherapy. Therefore, we postulated that chemotherapy-resistant prostate cancer has developed a lesion in the apoptosis signal transduction cascade. In this study, we investigated the mechanism underlying the resistance of apoptosis-insensitive prostate cancer cells to apoptosis. We approached this by comparing the response of the androgen-sensitive LNCaP cell line and the androgen-insensitive PC3 cell line to treatment with the topoisomerase I inhibitor, camptothecin. We demonstrated that LNCaP cells are susceptible to camptothecin-induced cell death, and PC3 cells are resistant. Additional studies confirmed that the mode of cell death in the LNCaP cells was by apoptosis. We then determined that a component of the resistance to death in the apoptosis-insensitive cells involved a defect in the generation of ceramide, a key lipid mediator of apoptosis. Specifically, we demonstrated that PC3 cells are unable to elevate ceramide in response to treatment with camptothecin. In contrast, elevations in ceramide levels occur in LNCaP cells in response to the same treatment. Significantly, additional studies showed that treatment with exogenous ceramide overcomes the lesion in the PC3 cells and induces apoptosis. In attempting to gain preliminary insight into the nature of the lesion in ceramide formation in the apoptosis-resistant cells, we established that generation of ceramide in LNCaP cells is independent of the de novo pathway. These studies present novel insights into the mechanism by which prostate cancer cells may be resistant to induction of apoptosis. The significance of this study lies in the fact that an understanding of the biological and molecular events contributing to the resistance of prostate cancer to therapy is crucial to the development of more effective regimens for advanced disease.
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Delta9-Tetrahydrocannabinol, the main active component of marijuana, induces apoptosis of transformed neural cells in culture. Here, we show that intratumoral administration of Delta9-tetrahydrocannabinol and the synthetic cannabinoid agonist WIN-55,212-2 induced a considerable regression of malignant gliomas in Wistar rats and in mice deficient in recombination activating gene 2. Cannabinoid treatment did not produce any substantial neurotoxic effect in the conditions used. Experiments with two subclones of C6 glioma cells in culture showed that cannabinoids signal apoptosis by a pathway involving cannabinoid receptors, sustained ceramide accumulation and Raf1/extracellular signal-regulated kinase activation. These results may provide the basis for a new therapeutic approach for the treatment of malignant gliomas.
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The human acid ceramidase gene, that causes Farber disease, is located in 8p22, a region frequently altered in several cancers, including prostate cancer. Acid ceramidase catalyzes the hydrolysis of ceramide, a potent lipid second messenger molecule that promotes apoptosis and inhibits cellular proliferation. It is not known whether this gene, or its expression, is altered in prostate cancer. Here, we report the structural organization of the human gene, its expression in human tissues, and the identification of several single nucleotide polymorphisms. No cancer‐related mutations were found in the gene in a panel of prostate tumor DNAs analyzed, but increased expression was observed in prostate tumor tissues when compared with matched normals. This increase was observed in all three prostate tumor cell lines tested (DU145, LnCAP, and PC3) when compared to a BPH (benign prostatic hyperplasia) cell line and 15/36 prostate tumors. These results suggest that acid ceramidase may play an important role in prostate carcinogenesis. © 2000 Wiley‐Liss, Inc.
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Anandamide and 2-arachidonoylglycerol (2-AG), two endogenous ligands of the CB1 and CB2 cannabinoid receptor subtypes, inhibit the proliferation of PRL-responsive human breast cancer cells (HBCCs) through down-regulation of the long form of the PRL receptor (PRLr). Here we report that 1) anandamide and 2-AG inhibit the nerve growth factor (NGF)-induced proliferation of HBCCs through suppression of the levels of NGF Trk receptors; 2) inhibition of PRLr levels results in inhibition of the proliferation of other PRL-responsive cells, the prostate cancer DU-145 cell line; and 3) CB1-like cannabinoid receptors are expressed in HBCCs and DU-145 cells and mediate the inhibition of cell proliferation and Trk/PRLr expression. β-NGF-induced HBCC proliferation was potently inhibited (IC50 = 50–600 nm) by the synthetic cannabinoid HU-210, 2-AG, anandamide, and its metabolically stable analogs, but not by the anandamide congener, palmitoylethanolamide, or the selective agonist of CB2 cannabinoid receptors, BML-190. Th...
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Androgens affect growth of the prostate gland and many prostate cancers. Androgens could mediate their mitogenic effects on prostate cells by an autocrine loop involving epidermal growth factor (EGF) and transforming growth factor (TGF)-alpha that bind to the EGF/TGF-alpha receptor. We examined the effects of 5 alpha-dihydrotestosterone (DHT) and testosterone (T), EGF, and EGF-alpha on cell proliferation and 3H-thymidine incorporation in an androgen-dependent human prostate cancer cell line, ALVA101, in serum-free medium. The regulation of TGF-alpha and EGF/TGF-alpha receptor messenger RNA (mRNA) levels were determined by Northern blot analysis and EGF/TGF-alpha receptor protein by immunoblot. After 24 h of treatment of ALVA101 cells with DHT (10(-8) M) or T (10(-8) M), TGF-alpha mRNA levels increased 3- and 2.5-fold, respectively, and EGF/TGF-alpha receptor mRNA levels 2- and 1.5-fold, respectively. Cell numbers increased at day 5 in response to 10(-8) M DHT (18%, P < 0.01), 10(-8) M T (15%, P < 0.01), 2...
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The human acid ceramidase gene, that causes Farber disease, is located in 8p22, a region frequently altered in several cancers, including prostate cancer. Acid ceramidase catalyzes the hydrolysis of ceramide, a potent lipid second messenger molecule that promotes apoptosis and inhibits cellular proliferation. It is not known whether this gene, or its expression, is altered in prostate cancer. Here, we report the structural organization of the human gene, its expression in human tissues, and the identification of several single nucleotide polymorphisms. No cancer-related mutations were found in the gene in a panel of prostate tumor DNAs analyzed, but increased expression was observed in prostate tumor tissues when compared with matched normals. This increase was observed in all three prostate tumor cell lines tested (DU145, LnCAP, and PC3) when compared to a BPH (benign prostatic hyperplasia) cell line and 15/36 prostate tumors. These results suggest that acid ceramidase may play an important role in prostate carcinogenesis. © 2000 Wiley-Liss, Inc.
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LNCaP cells (derived from a lymph node carcinoma of the human prostate) contain androgen receptors and show androgen-responsive growth in vitro. Maximal effects on growth were seen at 0.1 nM of the synthetic androgen R1881 or 0.2 nM of epidermal growth factor (EGF); both compounds independently increased the growth rate 2–3 times.EGF-receptors were measured after 6 days culture in the presence or absence of 0.1 nM R1881. A 2.3–fold increase in receptor number/cell was found when binding was measured at 0°C (from 12,500 to 28,900 sites/cell in stimulated cells). The kD value (0.45 nM) was not affected by androgen treatment. The increase of EGF-receptor activity was first observed between 6 and 12 h after exposure to androgen.It is concluded that LNCaP cells are sensitive to low concentrations of EGF (or EGF-like compounds) and that one of the mechanisms involved in androgen action on these cells is an increase of EGF-receptor expression at the cell surface.
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Evidence for the role of the cannabimimetic fatty acid derivatives (CFADs), i.e. anandamide (arachidonoylethanolamide, AEA), 2-arachidonoylglycerol (2-AG) and palmitoylethanolamide (PEA), in the control of inflammation and of the proliferation of tumor cells is reviewed here. The biosynthesis of AEA, PEA, or 2-AG can be induced by stimulation with either Ca2+ ionophores, lipopolysaccharide, or platelet activating factor in macrophages, and by ionomycin or antigen challenge in rat basophilic leukemia (RBL-2H3) cells (a widely used model for mast cells). These cells also inactivate CFADs through re-uptake and/or hydrolysis and/or esterification processes. AEA and PEA modulate cytokine and/or arachidonate release from macrophages in vitro, regulate serotonin secretion from RBL-2H3 cells, and are analgesic in some animal models of inflammatory pain. However, the involvement of endogenous CFADs and cannabinoid CB1 and CB2 receptors in these effects is still controversial. In human breast and prostate cancer cells, AEA and 2-AG, but not PEA, potently inhibit prolactin and/or nerve growth factor (NGF)-induced cell proliferation. Vanillyl-derivatives of anandamide, such as olvanil and arvanil, exhibit even higher anti-proliferative activity. These effects are due to suppression of the levels of the 100 kDa prolactin receptor or of the high affinity NGF receptors (trk), are mediated by CB1–like cannabinoid receptors, and are enhanced by other CFADs. Inhibition of adenylyl cyclase and activation of mitogen-activated protein kinase underlie the anti-mitogenic actions of AEA. The possibility that CFADs act as local inhibitors of the proliferation of human breast cancer is discussed here.
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The long history of the medicinal use of Cannabis sativa and, more recently, of its chemical constituents, the cannabinoids, suggests that also the endogenous ligands of cannabinoid receptors, the endocannabinoids, and, particularly, their derivatives may be used as therapeutic agents. Studies aimed at correlating the tissue and body fluid levels of endogenous cannabinoid-like molecules with pathological conditions have been started and may lead to identify those diseases that can be alleviated by drugs that either mimic or antagonize the action of these substances, or modulate their biosynthesis and degradation. Hints for the therapeutic applications of endocannabinoids, however, can be obtained also from our previous knowledge of marijuana medicinal properties. In this article, we discuss the anti-tumor and anti-inflammatory activity of: (1) the endocannabinoids anandamide (arachidonoylethanolamide) and 2-arachidonoyl glycerol; (2) the bioactive fatty acid amides palmitoylethanolamide and oleamide; and (3) some synthetic derivatives of these compounds, such as the N-acyl-vanillyl-amines. Furthermore, the possible role of cannabimimetic fatty acid derivatives in the pathological consequences of cancer and inflammation, such as cachexia, wasting syndrome, chronic pain and local vasodilation, will be examined.
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Anandamide (ANA) inhibits prolactin- and nerve growth factor (NGF)-induced proliferation of human breast cancer cells by decreasing the levels of the 100 kDa prolactin receptor (PRLr) and the high affinity trk NGF receptor, respectively, and by acting via CB(1)-like cannabinoid receptors. However, the intracellular signals that mediate these effects are not known. Here, we show that, in MCF-7 cells: (i) forskolin and the mitogen-activated protein kinase (MAPK) kinase inhibitor PD098059 prevent, and the protein kinase A inhibitor RpcAMPs mimics, the inhibitory effects of ANA on cell proliferation and PRLr/trk expression and (ii) ANA inhibits forskolin-induced cAMP formation and stimulates Raf-1 translocation and MAPK activity, in a fashion sensitive to the selective CB(1) antagonist SR141716A. ANA stimulation of MAPK was enhanced by inhibitors of ANA hydrolysis. Forskolin inhibited MAPK and ANA-induced Raf-1 translocation. These findings indicate that, in MCF-7 cells, ANA inhibits adenylyl cyclase and activates MAPK, thereby exerting a down-regulation on PRLr and trk levels and a suppression of cell proliferation.
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Results of recent studies indicate that cultured, androgen-independent prostatic carcinoma cells synthesize and secrete transforming growth factor alpha, which interacts with epidermal growth factor receptors (EGFRs) to promote autonomous growth. In the present study, we evaluated the expression and constitutive activation of EGFRs in normal prostatic epithelial cells and the androgen-independent prostatic carcinoma cell lines PC3 and DU145. Our studies showed that cultured normal epithelial cells and androgen-independent prostatic carcinoma cells actively synthesize and exhibit constitutive phosphorylation of the M(r) 170,000 EGFR. The addition of monoclonal anti-EGFR reduced receptor phosphorylation and significantly inhibited the proliferation of prostatic tumor cells. The observed reduction in EGFR phosphorylation could be partially attributed to an antibody-induced decrease in the expression of metabolically labeled EGFR. Results of further studies showed that anti-EGFR enhanced the sensitivity of PC3 cells to the cytotoxic and cytostatic effects of tumor necrosis factor alpha. These studies demonstrate that constitutive activation of EGFR in androgen-independent prostatic carcinoma plays a functional role in the regulation of cellular proliferation in vitro. In addition, the enhanced sensitivity of prostatic carcinoma cells to tumor necrosis factor alpha in the presence of anti-EGFR provides a rationale for the further investigation of combination therapy in the treatment of disseminated, androgen-independent disease.
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Development of suitable methods for the quantification of the proliferative response of airway smooth muscle (ASM) cells in culture will assist the investigation of the cellular mechanisms underlying the hyperplasia and hypertrophy of ASM as seen in asthmatic airways. In this study, two rapid and simple colorimetric assays have been modified to enable the growth of human bronchial and rabbit tracheal smooth muscle in culture to be assessed. One method depends upon the reduction by living cells of the tetrazolium salt MTT to form a blue formazan product, whereas the other relies on rapid binding of the dye Coomassie brilliant blue to protein at acidic pH. Experiments demonstrated the validity of both assays in quantifying the proliferative response of cultured human and rabbit ASM cells. The increase in optical density observed for each assay correlated directly, throughout the duration of culture, with the increase in cell number determined by hemocytometry in human and rabbit ASM cells proliferating in response to fetal calf serum (1.25 to 10%). This relationship held also for rabbit tracheal ASM cells proliferating in response to the heterodimer of platelet-derived growth factor (1 to 50 ng/ml). Application of these methods to adherent proliferating cultures of human and rabbit ASM cells demonstrated their adaptability to the generation of growth curves in response to serum and to a defined growth factor. These methods allow both total cellular protein and proliferation to be estimated in human and rabbit ASM cells in culture, using assays that are rapid, reproducible, inexpensive, and easy to perform while negating the use of radioisotopes. It is intended that these additional methods should be useful in delineating some of the mechanisms that might contribute to the proliferative response of these cells--particularly since there has been a resurgence in interest in culturing smooth muscle cells derived from the airways.
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To increase survival of men with metastatic prostatic cancer, a modality that can effectively eliminate androgen independent cancer cells is desperately needed. By combining such an effective modality with androgen ablation, all of the heterogeneous populations of tumour cells within a prostatic cancer patient can be affected, thus optimizing the chances of cure. Unfortunately, such effective therapy for the androgen independent prostatic cancer cell is not yet available. This therapy will probably require two types of agents, one having antiproliferative activity affecting the small number of dividing androgen independent cells, and the other able to increase the low rate of cell death among the majority of non-proliferating (ie interphase) androgen independent prostatic cancer cells present. Androgen dependent prostatic epithelial cells can be made to undergo programmed death by means of androgen ablation, even if the cells are not in the proliferative cell cycle. Androgen independent prostatic cancer cells retain the major portion of this programmed cell death pathway, only there is a defect in the pathway such that it is no longer activated by androgen ablation. If the intracellular free Ca2+ is sustained at an elevated level for a sufficient time, androgen independent cells can be induced to undergo programmed death. The long term goal is therefore to develop some type of non-androgen ablative method that can be used in vivo to induce a sustained elevation in Ca2+ in androgen independent prostatic cancer cells. To accomplish this task, a more complete understanding of the biochemical pathways involved in programmed cell death is urgently needed. At present, studies are focusing on the mechanism involved in the Ca2+ elevation in the normal and malignant androgen dependent cell induced following androgen ablation and the role of the TRPM-2 protein in this process.
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To improve survival in men with metastatic prostatic cancer, a therapeutic modality that can effectively eliminate androgen-independent cancer cells is needed desperately. Combination of such an effective modality with androgen ablation could affect all of the heterogeneous populations within prostate tumors of individual patients, thus optimizing the chances of complete cure. Such a therapeutic approach will probably require two types of agents, one with antiproliferative activity affecting the small number of dividing androgen-independent cells and one with the capacity to increase the rate of cell death among the non-proliferating androgen-independent prostatic cancer cells present, i.e. the majority. Androgen-responsive human prostate cancer cells are able to undergo programmed cell death after androgen ablation (even if the cells are not in the proliferative cell cycle). Androgen-independent human prostate cancer cells, however, do not activate this apoptotic pathway of cell death in response to androgen ablation. In contrast, androgen-independent human prostate cancer cells can be induced to undergo apoptosis following such alternative treatment modalities as: (a) non-androgen ablative cytotoxic drugs, such as fluorinated pyrimidines, which result in the "thymine-less state", and (b) ionizing irradiation. The apoptotic effect induced by radiation can be significantly potentiated by post-irradiation treatment of the cells with suramin. In contrast, this radiation induced apoptosis can be substantially inhibited by pretreatment of cells with suramin, probably through suramin's ability to arrest proliferating cells in the GO/Gl phase of the cell cycle. These results suggest that treatment of prostate cancer patients with suramin prior to irradiation is likely to inhibit radiation palliation.(ABSTRACT TRUNCATED AT 250 WORDS)
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A number of enzymatic techniques have recently been developed to detect DNA fragmentation in apoptosis at the cellular level. However, since DNA fragmentation also occurs in cellular necrosis, we studied to which extent the use of DNA polymerase (nick translation) or terminal transferase (tailing) allows the differentiation between internucleosomal DNA degradation, typical for apoptosis, and the more random DNA destruction in necrosis. We compared these techniques on in vitro and in vivo models for apoptotic or necrotic cell death. Apoptosis of thymocytes in vitro was induced by gamma-irradiation, necrosis by the cytotoxic action of antibody and complement. Cell death in vivo was examined on paraffin-embedded tissue material from animals with autoimmune encephalomyelitis that served as a model for apoptosis, or in kainic acid-induced nerve cell degeneration as a model for necrosis. DNA fragmentation was visualized by the incorporation of labeled nucleotides into the nuclei of affected cells utilizing tailing or nick translation techniques. In the early stages of cell degeneration in vitro, cells undergoing apoptosis were preferentially labeled by tailing, whereas necrotic cells were identified by nick translation. Similarly, early stages of necrosis in vivo were preferentially detected by nick translation, whereas tailing was slightly more sensitive for the detection of apoptosis. Results obtained with these enzymatic techniques were in accord with the assessment of cell death by morphologic criteria. Both techniques could be applied in tissue samples even after prolonged fixation in paraformaldehyde if the sections were pretreated with proteinase K digestion. Our studies show that both in situ nick translation and in situ tailing are useful in detecting DNA fragmentation in cell suspensions and tissue sections. These techniques may help to define the molecular mechanisms leading to cell death in experimental conditions and eventually in human tissue.
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Androgens affect growth of the prostate gland and many prostate cancers. Androgens could mediate their mitogenic effects on prostate cells by an autocrine loop involving epidermal growth factor (EGF) and transforming growth factor (TGF)-alpha that bind to the EGF/TGF-alpha receptor. We examined the effects of 5 alpha-dihydrotestosterone (DHT) and testosterone (T), EGF, and EGF-alpha on cell proliferation and 3H-thymidine incorporation in an androgen-dependent human prostate cancer cell line, ALVA101, in serum-free medium. The regulation of TGF-alpha and EGF/TGF-alpha receptor messenger RNA (mRNA) levels were determined by Northern blot analysis and EGF/TGF-alpha receptor protein by immunoblot. After 24 h of treatment of ALVA101 cells with DHT (10(-8) M) or T (10(-8) M), TGF-alpha mRNA levels increased 3- and 2.5-fold, respectively, and EGF/TGF-alpha receptor mRNA levels 2- and 1.5-fold, respectively. Cell numbers increased at day 5 in response to 10(-8) M DHT (18%, P < 0.01), 10(-8) M T (15%, P < 0.01), 20 ng/ml EGF (16%, P < 0.01), and 50 ng/mL TGF-alpha (34%, P < 0.01). DHT combined with TGF-alpha or T combined with EGF increased cell number 43% and 40% above control, respectively (P < 0.01 vs. DHT, P < 0.05 vs. TGF-alpha, T, EGF alone). The anti-EGF/TGF-alpha receptor antibody (528) blocked the cell proliferation induced by either DHT or TGF-alpha. We conclude that DHT and T stimulate synthesis of TGF-alpha and EGF/TGF-alpha receptor mRNAs and EGF/TGF-alpha receptor content in ALVA101 cells. This mitogenic effect of androgen on ALVA101 cells may involve TGF-alpha and the EGF/TGF-alpha receptor autocrine loop.
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Prostate adenocarcinoma, the most common tumor occurring among North American men, preferentially metastasizes to bone, where it characteristically forms osteoblastic lesions. The following growth regulatory factors are expressed in some human prostate cancers and/or established cell lines: epidermal growth factor (EGF), transforming growth factor alpha, transforming growth factor beta, basic fibroblast growth factor (bFGF), and insulin-like growth factor. Some of these, especially EGF, bFGF, and TGF-beta, are also implicated in growth regulation in normal and benign hyperplastic prostates. Although evidence from in vitro study of the small number of prostate cell lines available demonstrates that these growth regulatory pathways are exploited by some of these cells, direct in vivo evidence is limited. The development of human prostate cancer cell lines which grow and metastasize in immune-deficient rodents is an advance which now permits experimental analysis of the role of these growth factors in prostatic metastasis, particularly to bone. The progression and metastasis of human prostate cancer results from the complex interactions of multiple growth factors, androgens, and cellular communication, which form a dynamic network. Continued progress in the study and treatment of this disease will require new conceptual frameworks as well as successful application of the techniques of molecular and cellular biology.
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