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ABSTRACT: PD-L1 (CD274) contributes to functional exhaustion of T cells and limits immune responses in patients with cancer. In this study, we report the identification of an HLA-A2-restricted epitope from PD-L1 and we describe natural, cytolytic T-cell reactivity against PD-L1 in the peripheral blood of cancer patients and healthy individuals. Notably, PD-L1-specific T cells were able not only to recognize and kill tumor cells, but also PD-L1-expressing dendritic cells (DC) in a PD-L1-dependent manner, insofar as PD-L1 ablation rescued DC from killing. Furthermore, by incubating non-professional antigen presenting cells (APC) with long peptides from PD-L1 we found that PDL1 was rapidly internalized, processed and cross-presented by HLA-A2 on the cell surface. Apparently, this cross presentation was TAP-independent, since it was performed not only by Bcells but in addition by TAP-deficient T2-cells. This is intriguing, since soluble PD-L1 has been detected in the sera from cancer patients. PD-L1-specific cytotoxic T cells (CTL) may boost immunity by the killing of immune suppressive tumor cells as well as regulatory cells. However, PD-L1-specific CTL may as well suppress immunity by the elimination of normal immune cells especially PD-L1 expressing mature DC.
Cancer Research 01/2013; · 7.86 Impact Factor
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ABSTRACT: T cells in tumors-the so-called tumor infiltrating lymphocytes (TIL) have been studied intensively over the past years. Compelling evidence point to a clinical relevance for high numbers of T cells at the tumor site with CD8 memory T cells as a key denominator for overall survival (OS) in patients with colo-rectal cancer (CRC), and also for others solid cancers. These data goes hand in hand with studies of clonality of TIL showing the T cells among TIL are expanded clonally, and also that tumor specific T cells of CD4 as well as CD8 type are enriched at the tumor site. The tumor microenvironment is hostile to T cell function e.g., due to expression of enzymes that depletes the amino acids tryptophan and arginine, high concentration of tumor secreted lactate, and presence innate cells or regulatory T cells both with suppressive activity. Analyses of the specificity of TILs in melanoma demonstrate that quite few known antigens are in fact recognized by these cultures underscoring patient unique and/or mutated antigens may represent important target for recognition.
Cancer Microenvironment 12/2012;
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ABSTRACT: In spite of the fact that they occur at high rates, the clinical responses of BRAF(V600) mutant metastatic melanoma to BRAF inhibitors are usually short-lasting, with most cases progressing within less than 8 mo. Immunomodulatory strategies initiated after progression have recently been reported to be poorly efficient. By characterizing the immunological interactions between T cells and cancer cells in clinical material as well as the influence of the FDA-approved BRAF inhibitor vemurafenib on the immune system, we aimed at unraveling new strategies to expand the efficacy of adoptive T-cell transfer, which represents one of the most promising approaches currently in clinical development for the treatment of metastatic melanoma. Here we show that blocking the BRAF-MAPK pathway in BRAF signaling-addicted melanoma cells significantly increases the ability of T cells contained in clinical grade tumor-infiltrating lymphocytes to recognize autologous BRAF(V600) mutant melanoma cell lines in vitro. Antitumor reactivity was improved regardless of the class of antigen recognized by tumor-specific CD8(+) T cells. Microarray data suggests that improved tumor recognition is associated with modified expression of MHC Class I-associated proteins as well as of heat-shock proteins. In conclusion, our preclinical data suggest that an appropriately timed sequential treatment of BRAF(V600) mutant melanoma with vemurafenib and adoptive T-cell transfer might result in synergistic antineoplastic effects owing to an increased immunogenicity of cancer cells.
Oncoimmunology. 12/2012; 1(9):1476-1483.
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James A McCubrey,
Linda S Steelman,
William H Chappell,
Lin Sun,
Nicole M Davis,
Stephen L Abrams,
Richard A Franklin,
Lucio Cocco,
Camilla Evangelisti,
Francesca Chiarini, [......],
Michele Michele,
Agostino Tafuri,
Joanna Dulińska-Litewka,
Piotr Laidler,
Antonio B D'Assoro,
Lyudmyla Drobot,
Drobot Umezawa,
Giuseppe Montalto,
Melchiorre Cervello,
Zoya N Demidenko
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ABSTRACT: Over the past few years, significant advances have occurred in both our understanding of the complexity of signal transduction pathways as well as the isolation of specific inhibitors which target key components in those pathways. Furthermore critical information is being accrued regarding how genetic mutations can affect the sensitivity of various types of patients to targeted therapy. Finally, genetic mechanisms responsible for the development of resistance after targeted therapy are being discovered which may allow the creation of alternative therapies to overcome resistance. This review will discuss some of the highlights over the past few years on the roles of key signaling pathways in various diseases, the targeting of signal transduction pathways and the genetic mechanisms governing sensitivity and resistance to targeted therapies.
Oncotarget 12/2012; 3(12):1505-21. · 4.78 Impact Factor
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ABSTRACT: Monocyte-derived dendritic cells (DCs) used for immunotherapy e.g. against cancer are commonly matured by pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) and prostaglandin E(2) although the absence of Toll-like receptor mediated activation prevents secretion of IL-12 from DCs and subsequent efficient induction of type 1 effector T cells. Standard matured clinical grade DCs "sDCs" were compared with DCs matured with either of two type 1 polarizing maturation cocktails; the alpha-type-1 DCs "αDC1s" (TNF-α, IL-1β, IFN-γ, IFN-α, Poly(I:C)) and "mDCs" (monophosphoryl lipid A (MPL), IFN-γ) or a mixed cocktail - "mpDCs", containing MPL, IFN-γ and PGE(2). αDC1s and mDCs secreted IL-12 directly and following re-stimulation with CD40L-expressing cells and they mainly secreted the T effector cell attracting chemokines CXCL10 and CCL5 as opposed to sDCs that mainly secreted CCL22, known to attract regulatory T cells. αDC1s and mDCs were functionally superior to sDCs as they polarized naïve CD4(+) T cells most efficiently into T helper type 1 effector cells and primed more functional MART-1 specific CD8(+) T cells although with variation between donors. αDC1s and mDCs were transiently less capable of CCL21-directed transwell migration than standard matured DCs, likely due to their increased secretion of CCL19, which mediate internalization of CCR7. mpDCs were intermediate between standard and polarized DCs both in terms of IL-12 secretion and transwell migratory ability but functionally they resembled sDCs and strikingly had the highest expression of the inhibitory molecules PD-L1 and CD25. Thus, further studies with type 1 polarized DCs are warranted for use in immunotherapy, but when combined with PGE(2) as in mpDCs, they seems to be less optimal for maturation of DCs.
Vaccine 11/2012; · 3.77 Impact Factor
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ABSTRACT: γδ T cells, including Vδ1 and Vδ2 T cells, can recognize tumor-associated ligands neglected by conventional αβ T cells in a MHC-independent manner. Little is known regarding the anticancer potential and the possibility to isolate and expand Vδ1 T cells to therapeutically relevant numbers. In this study, we have detected low frequencies of Vδ1 T cells among tumor-infiltrating lymphocyte (TIL) products for adoptive cell transfer generated from melanoma metastases. An increased frequency of Vδ1 T cells was found among the cell products from patients with an advanced disease stage. Vδ1 T cells displayed in vitro antitumor activities and sufficient proliferative potential to generate over 1 × 10(9) cells using current protocols for T cell transfer. Infusion of Vδ1 T cells together with high numbers of αβ TILs in a clinical trial was safe and well tolerated. These data suggest that Vδ1 T cells should be further scrutinized as a potentially useful tool for the treatment of patients with metastatic melanoma.
Oncoimmunology. 11/2012; 1(8):1297-1304.
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ABSTRACT: Further development of adoptive T-cell therapy (ACT) with autologous tumor-infiltrating lymphocytes (TILs) has the potential to markedly change the long-term prognosis of patients with metastatic melanoma, and modifications of the original protocol that can improve its clinical efficacy are highly desirable. In this study, we demonstrated that a high in vitro tumor reactivity of infusion products was associated with clinical responses upon adoptive transfer. In addition, we systematically characterized the responses of a series of TIL products to relevant autologous short term-cultured melanoma cell lines from 12 patients. We provide evidence that antitumor reactivity of both CD8(+) and CD4(+) T cells could be enhanced in most TIL products by autologous melanoma sensitization by pretreatment with low-dose IFN-γ. IFN-γ selectively enhanced responses to tumor-associated antigens other than melanoma differentiation antigens. In addition, IFN-γ treatment was invariably associated with restored/increased cancer immunogenicity as demonstrated by upregulation of major histocompatibility complex molecules. These findings suggest a potential synergism between IFN-γ and ACT, and have important implications for clinical development of combination strategies for the treatment of metastatic melanoma.Journal of Investigative Dermatology advance online publication, 27 September 2012; doi:10.1038/jid.2012.336.
Journal of Investigative Dermatology 09/2012; · 6.31 Impact Factor
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Eva Ellebaek,
Trine Zeeberg Iversen,
Niels Junker, Marco Donia,
Lotte Engell-Noerregaard,
Ozcan Met,
Lisbet Rosenkrantz Hölmich,
Rikke Sick Andersen,
Sine Reker Hadrup,
Mads Hald Andersen,
Per Thor Straten,
Inge Marie Svane
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ABSTRACT: BACKGROUND: Adoptive cell therapy may be based on isolation of tumor-specific T cells, e.g. autologous tumor infiltrating lymphocytes (TIL), in vitro activation and expansion and the reinfusion of these cells into patients upon chemotherapy induced lymphodepletion. Together with high-dose interleukin (IL)-2 this treatment has been given to patients with advanced malignant melanoma and impressive response rates but also significant IL-2 associated toxicity have been observed. Here we present data from a feasibility study at a Danish Translational Research Center using TIL adoptive transfer in combination with low-dose subcutaneous IL-2 injections. METHODS: This is a pilot trial (Clinical trials.gov identifier: NCT00937625) including patients with metastatic melanoma, PS [LESS-THAN OR EQUAL TO]1, age <70, measurable and progressive disease and no involvement of the central nervous system. Six patients were treated with lymphodepleting chemotherapy, TIL infusion, and 14 days of subcutaneous low-dose IL-2 injections, 2 MIU/day. RESULTS: Low-dose IL-2 considerably decreased the treatment related toxicity with no grade 3--4 IL-2 related adverse events. Objective clinical responses were seen in 2 of 6 treated patients with ongoing complete responses (30+ and 10+ months), 2 patients had stable disease (4 and 5 months) and 2 patients progressed shortly after treatment. Tumor-reactivity of the infused cells and peripheral lymphocytes before and after therapy were analyzed. Absolute number of tumor specific T cells in the infusion product tended to correlate with clinical response and also, an induction of peripheral tumor reactive T cells was observed for 1 patient in complete remission. CONCLUSION: Complete and durable responses were induced after treatment with adoptive cell therapy in combination with low-dose IL-2 which significantly decreased toxicity of this therapy.
Journal of Translational Medicine 08/2012; 10(1):169. · 3.41 Impact Factor
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Marija Mojic,
Sanja Mijatovic,
Danijela Maksimovic-Ivanic,
Djordje Miljkovic,
Stanislava Stosic-Grujicic,
Marija Stankovic,
Katia Mangano,
Salvatore Travali, Marco Donia,
Paolo Fagone,
Mai-Britt Zocca,
Yousef Al-Abed,
James A McCubrey,
Ferdinando Nicoletti
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ABSTRACT: We have examined the influence of the nitric oxide (NO)-modified anti-inflammatory drug (S,R)-3-phenyl-4,5-dihydro-5-isoxasole acetic acid (VGX-1027) named GIT-27NO or the NO-modified antiviral drug saquinavir (Saq) named Saq-NO on two colon cancer cell lines, mouse CT26CL25 and human HCT116. The effects of the drugs on cell viability, apoptosis, proliferation, and metastatic potential were analyzed. The release of NO and oxygen and nitrogen species was also determined. The efficacy of the drugs was evaluated in vivo in BALB/c mice injected with CT26CL25 cells. Both agents suppressed the growth of colon cancer cells in vitro and reduced tumor volume in syngeneic BALB/c mice. However, their mechanisms of action were different because GIT-27NO released larger amounts of nitrite than Saq-NO in cell cultures and its antitumor action depended on the intracellular NO release inside the cells. On the contrary, Saq-NO released barely detectable amounts of NO and its antitumor action was NO-independent. In fact, cotreatment with an NO-peroxynitrite scavenger revealed that GIT-27NO but not Saq-NO acts through peroxynitrite-mediated cell destruction. At the cellular level, GIT-27NO prevalently induced proapoptotic signals followed by caspase-dependent apoptosis. In contrast, Saq-NO blocked cell proliferation, changed the adhesive, migratory, and invasive properties of the cells, and decreased metastatic potential in vivo. In conclusion, differences in NO release and oxidative stress generation between GIT-27NO and Saq-NO resulted in different mechanisms that caused cell death.
Molecular pharmacology 07/2012; 82(4):700-10. · 4.53 Impact Factor
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ABSTRACT: Rapamycin is a macrocyclic lactone currently used for the treatment of cancer and for the prevention of transplant rejection. The primary pharmacological mode of action of rapamycin occurs through the inhibition (blocking) of the mammalian target of rapamycin (mTOR). By doing so, rapamycin interferes with the phosphoinositide 3-kinase (PI3K)-Akt-mTOR axis that controls several cellular functions involving cell growth, proliferation and angiogenesis. The frequent activation of the phosphoinositide 3-kinase (PI3K)/AKT pathway in advanced prostate cancer has provided a rationale for the use of mTOR inhibitors in this setting. We carried out a comparative study on the effects of rapamycin and temsirolimus on the in vitro and in vivo growth of the prostate cancer cell lines, LnCap and PC3. Our results demonstrate that rapamycin and temsirolimus exert similar in vitro and in vivo anti-proliferative effects against prostate cancer cells.
Basic & Clinical Pharmacology & Toxicology 07/2012; · 2.18 Impact Factor
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Marco Donia,
Katia Mangano,
Paolo Fagone,
Rocco De Pasquale,
Franco Dinotta,
Marinella Coco,
Julio Padron,
Yousef Al-Abed,
Giuseppe Angelo Giovanni Lombardo,
Danijela Maksimovic-Ivanic,
Sanja Mijatovic,
Mai-Britt Zocca,
Vincenzo Perciavalle,
Stanislava Stosic-Grujicic,
Ferdinando Nicoletti
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ABSTRACT: We have recently shown that covalent attachment of the nitric oxide (NO) moiety to the HIV protease inhibitor Saquinavir (Saq) produced a qualitatively new chemical entity, named Saquinavir-NO (Saq-NO), with enhanced anticancer properties and reduced toxicity both in vitro and in vivo. The aim of this study was to address several unanswered questions both on the pharmacological profile of Saq-NO as well as on the in vivo role of NO in the oncogenesis of A375 human melanoma cells. To this end, we have evaluated here the impact of single and combined effects of Saq-NO, Saq, the NO-donor DETA NONOate and the iNOS inhibitor L-NAME on the in vitro as well as in vivo growth of the iNOS positive A375 cells. Our data confirm clear-cut evidence for a strong and powerful anti-melanoma action of Saq-NO that is not duplicable by the combined use of Saq and DETA NONOate. Surprisingly, but also in agreement with the complex and multifaceted role of endogenous NO in A375 cells, both DETA NONOate and L-NAME significantly suppressed the in vivo growth of xenotransplants.
Oncology Reports 05/2012; 28(2):682-8. · 1.84 Impact Factor
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ABSTRACT: Tumor-infiltrating lymphocytes (TIL) isolated from melanoma patients and expanded in vitro by interleukin (IL)-2 treatment can elicit therapeutic response after adoptive transfer, but the antigen specificities of the T cells transferred have not been determined. By compiling all known melanoma-associated antigens and applying a novel technology for high-throughput analysis of T-cell responses, we dissected the composition of melanoma-restricted T-cell responses in 63 TIL cultures. T-cell reactivity screens against 175 melanoma-associated epitopes detected 90 responses against 18 different epitopes predominantly from differentiation and cancer-testis antigens. Notably, the majority of these responses were of low frequency and tumor-specific T-cell frequencies decreased during rapid expansion. A further notable observation was a large variation in the T-cell specificities detected in cultures established from different fragments of resected melanoma lesions. In summary, our findings provide an initial definition of T-cell populations contributing to tumor recognition in TILs although the specificity of many tumor-reactive TILs remains undefined.
Cancer Research 02/2012; 72(7):1642-50. · 7.86 Impact Factor
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Cancer Immunology and Immunotherapy 02/2012; 61(8):1349-53. · 3.70 Impact Factor
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ABSTRACT: Adoptive cell transfer (ACT) of in vitro expanded autologous tumor-infiltrating lymphocytes (TIL) has been shown to exert therapeutic efficacy in melanoma patients. We aimed to develop an ACT protocol based on tumor-specific T cells isolated from peripheral blood and in vitro expanded by Dynabeads® ClinExVivo™CD3/CD28. We show here that the addition of an in vitro restimulation step with relevant peptides prior to bead expansion dramatically increased the proportion of tumor-specific T cells in PBMC-cultures. Importantly, peptide-pulsed dendritic cells (DCs) as well as allogeneic tumor lysate-pulsed DCs from the DC vaccine preparation could be used with comparable efficiency to peptides for in vitro restimulation, to increase the tumor-specific T-cell response. Furthermore, we tested the use of different ratios and different types of Dynabeads® CD3/CD28 and CD3/CD28/CD137 T-cell expander, for optimized expansion of tumor-specific T cells. A ratio of 1:3 of Dynabeads® CD3/CD28 T-cell expander to T cells resulted in the maximum number of tumor-specific T cells. The addition of CD137 did not improve functionality or fold expansion. Both T-cell expansion systems could generate tumor-specific T cells that were both cytotoxic and effective cytokine producers upon antigen recognition. Dynabeads®-expanded T-cell cultures shows phenotypical characteristics of memory T cells with potential to migrate and expand in vivo. In addition, they possess longer telomeres compared to TIL cultures. Taken together, we demonstrate that in vitro restimulation of tumor-specific T cells prior to bead expansion is necessary to achieve high numbers of tumor-specific T cells. This is effective and easily applicable in combination with DC vaccination, by use of vaccine-generated DCs, either pulsed with peptide or tumor-lysate.
Cancer Immunology and Immunotherapy 01/2012; 61(8):1221-31. · 3.70 Impact Factor
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ABSTRACT: The enzyme indoleamine 2,3-dioxygenase (IDO) contributes to immune tolerance in a variety of settings. In cancer IDO is expressed within the tumor itself as well as in antigen-presenting cells in tumor-draining lymph nodes, where it endorses the establishment of peripheral immune tolerance to tumor antigens. Recently, we described cytotoxic CD8(+) T-cell reactivity towards IDO-derived peptides.
In the present study, we show that CD4(+) helper T cells additionally spontaneously recognize IDO. Hence, we scrutinized the vicinity of the previously described HLA-A*0201-restricted IDO-epitope for CD4(+) T-cell epitopes. We demonstrated the presence of naturally occurring IDO-specific CD4(+) T cells in cancer patients and to a lesser extent in healthy donors by cytokine release ELISPOT. IDO-reactive CD4(+) T cells released IFN-γ, TNF-α, as well as IL-17. We confirm HLA class II-restriction by the addition of HLA class II specific blocking antibodies. In addition, we detected a trend between class I- and class II-restricted IDO responses and detected an association between IDO-specific CD4(+) T cells and CD8(+) CMV-responses. Finally, we could detect IL-10 releasing IDO-reactive CD4(+) T cells.
IDO is spontaneously recognized by HLA class II-restricted, CD4(+) T cells in cancer patients and in healthy individuals. IDO-specific T cells may participate in immune-regulatory networks where the activation of pro-inflammatory IDO-specific CD4(+) responses may well overcome or delay the immune suppressive actions of the IDO-protein, which are otherwise a consequence of the early expression of IDO in maturing antigen presenting cells. In contrast, IDO-specific regulatory T cells may enhance IDO-mediated immune suppression.
PLoS ONE 01/2012; 7(4):e34568. · 4.09 Impact Factor
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Sanja Mijatovic,
Danijela Maksimovic-Ivanic,
Marija Mojic,
Gordana Timotijevic,
Djordje Miljkovic,
Katia Mangano, Marco Donia,
Antonio Di Cataldo,
Yousef Al-Abed,
Kai Fan Cheng,
Stanislava Stosic-Grujicic,
Ferdinando Nicoletti
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ABSTRACT: We have recently shown that covalent attachment of the NO moiety to the HIV protease inhibitor Saquinavir (Saq) produced a qualitatively new chemical entity, named Saquinavir-NO (Saq-NO), with enhanced anticancer properties and reduced toxicity. In this study we evaluated the impact of Saq-NO on the growth of A375 human melanoma cells, as a prototype of NO-dependent cancer model. The novel compound strongly affected the in vitro and in vivo progression of A375 melanoma cell growth. The mechanism of antimelanoma action comprised dual drug activity-induction of apoptotic cell death and acquisition of melanoma cell responsiveness to TRAIL. Saq-NO-triggered apoptosis was dependent on transient AKT up-regulation and reduced pERK and iNOS expression that were observed within the first 12 h of exposure to the drug. Thereafter, however, Saq-NO up-regulated both iNOS transcription and NO endogenous synthesis and sensitized A375 cells to TRAIL. Furthermore, reduced YY1 expression was observed after 24 h of Saq-NO exposure, which correlated with increased expression of DR5. The biological relevance of this complex and powerful action of Saq-NO was consistent with the marked drug-induced inhibition of the growth of A375 xenotransplants in nude mice.
Journal of Cellular Physiology 07/2011; 226(7):1803-12. · 3.87 Impact Factor
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ABSTRACT: Preclinical studies have shown that the anti-glucocorticoid drug mifepristone effectively inhibits HIV replication both in vitro and in vivo. However, the drug did not demonstrate anti-HIV activity in a previous phase I/II study when administered at the daily dose of 75-225 mg. The aim of this study was to assess whether mifepristone may exert antiretroviral activity or influence immunological parameters when administered orally at daily doses of 150 or 300 mg in highly active antiretroviral therapy (HAART)-naïve HIV-infected patients. We performed an open label non-randomized phase II study that included 26 patients who underwent 28 days of once daily oral administration of 150 (12 subjects) or 300 mg (14 subjects) of mifepristone. A total of 3 patients dropped out of the study, respectively 1 in the 150 mg dose group and 2 in the 300 mg dose group. The main hemato-chemical alterations reported were hypokalemia and increase in the blood levels of cortisol, especially in those patients that received mifepristone at the dose of 300 mg/day. Although we observed a trend of reduced viral load along the study in both groups, statistical significance was not achieved for either the primary nor the secondary endpoints. In summary, mifepristone treatment was well-tolerated but it failed to significantly influence viro-immunological parameters in HAART-naïve HIV-infected patients.
International Journal of Molecular Medicine 05/2011; 28(3):437-42. · 1.98 Impact Factor
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William H Chappell,
Linda S Steelman,
Jacquelyn M Long,
Ruth C Kempf,
Stephen L Abrams,
Richard A Franklin,
Jörg Bäsecke,
Franca Stivala, Marco Donia,
Paolo Fagone, [......],
Giuseppe Montalto,
Melchiorre Cervello,
Piotr Laidler,
Michele Milella,
Agostino Tafuri,
Antonio Bonati,
Camilla Evangelisti,
Lucio Cocco,
Alberto M Martelli,
James A McCubrey
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ABSTRACT: The Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR cascades are often activated by genetic alterations in upstream signaling molecules such as receptor tyrosine kinases (RTK). Integral components of these pathways, Ras, B-Raf, PI3K, and PTEN are also activated/inactivated by mutations. These pathways have profound effects on proliferative, apoptotic and differentiation pathways. Dysregulation of these pathways can contribute to chemotherapeutic drug resistance, proliferation of cancer initiating cells (CICs) and premature aging. This review will evaluate more recently described potential uses of MEK, PI3K, Akt and mTOR inhibitors in the proliferation of malignant cells, suppression of CICs, cellular senescence and prevention of aging. Ras/Raf/MEK/ERK and Ras/PI3K/PTEN/Akt/mTOR pathways play key roles in the regulation of normal and malignant cell growth. Inhibitors targeting these pathways have many potential uses from suppression of cancer, proliferative diseases as well as aging.
Oncotarget 03/2011; 2(3):135-64. · 4.78 Impact Factor
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Linda S Steelman,
William H Chappell,
Stephen L Abrams,
Ruth C Kempf,
Jacquelyn Long,
Piotr Laidler,
Sanja Mijatovic,
Danijela Maksimovic-Ivanic,
Franca Stivala,
Maria C Mazzarino, [......],
Michele Milella,
Agostino Tafuri,
Antonio Bonati,
Jörg Bäsecke,
Lucio Cocco,
Camilla Evangelisti,
Alberto M Martelli,
Giuseppe Montalto,
Melchiorre Cervello,
James A McCubrey
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ABSTRACT: Dysregulated signaling through the Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR pathways is often the result of genetic alterations in critical components in these pathways or upstream activators. Unrestricted cellular proliferation and decreased sensitivity to apoptotic-inducing agents are typically associated with activation of these pro-survival pathways. This review discusses the functions these pathways have in normal and neoplastic tissue growth and how they contribute to resistance to apoptotic stimuli. Crosstalk and commonly identified mutations that occur within these pathways that contribute to abnormal activation and cancer growth will also be addressed. Finally the recently described roles of these pathways in cancer stem cells, cellular senescence and aging will be evaluated. Controlling the expression of these pathways could ameliorate human health.
Aging 03/2011; 3(3):192-222. · 5.13 Impact Factor
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Marco Donia,
Danijela Maksimovic-Ivanic,
Sanja Mijatovic,
Marija Mojic,
Djordje Miljkovic,
Gordana Timotijevic,
Paolo Fagone,
Salvatore Caponnetto,
Yousef Al-Abed,
James McCubrey,
Stanislava Stosic-Grujicic,
Ferdinando Nicoletti
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ABSTRACT: The NO-derivative of the HIV protease inhibitor saquinavir (Saq-NO) is a nontoxic variant of the parental drug with enhanced anticancer activity on several cell lines. However, it is still unclear whether the p53 status of the target cell might influence the sensitivity to Saq-NO. In this study we evaluated the in vitro and in vivo activity of Saq-NO on the p53-deficient hormone resistant prostate cancer PC-3 cells. We demonstrate that the absence of functional p53 is not essential for the capacity of Saq-NO to reduce prostate cancer cell growth. In contrast to its previously described cytostatic action in B16 and C6 cell lines, Saq-NO exerted cytotoxic effects in PC-3 cells leading to dominant induction of apoptosis and enhanced production of proapoptotic Bim. In addition, differently from saquinavir, Saq-NO restored TRAIL sensitivity that was correlated with increased expression of DR5 independent from ROS/RNS production and YY1 repression. NF-κB activation may be responsible of the Saq-NO induced DR5 expression. Moreover, Saq-NO but not saquinavir, exerted synergistic activity with conventional cytostatic therapy. In agreement with these in vitro studies, Saq-NO inhibited the in vivo growth of PC-3 cells xenotransplants to a greater extent than the parental compound. Taken together, these data indicate that Saq-NO possesses powerful and suitable in vitro and in vivo chemotherapeutic potential to be further studied as a novel drug for the treatment of prostate cancer in the clinical setting.
Cell cycle (Georgetown, Tex.) 02/2011; 10(3):492-9. · 5.36 Impact Factor