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ABSTRACT: 6-(N,N-Dimethylamino)-2-(naphthalene-1-yl)-4-quinazolinone (DPQZ)-induced apoptosis was accompanied by the characteristics of DNA fragmentation and phosphatidylserine externalization in human oral cancer HSC-3 cells. The IC(50) (half maximal inhibitory concentration) value of DPQZ is about 0.25 μM at 24 h. The interference in the dynamics of tubulin and cell division of DPQZ, like vinblastine (0.01 μM), has been proven in this study. Treatment of HSC-3 cells with DPQZ resulted in many of mitotic cells with multipolar spindles. Up-regulation of MAP kinases, such as ERK, JNK, and p38, mediated by DPQZ appears to be involved in DPQZ-induced apoptosis in HSC-3 cells. It is worthy of note that the expression of Ras and c-Raf that lie upstream of ERK were inhibited by DPQZ. In addition, the DPQZ-induced cell death was attenuated by JNK inhibitor SP600125 (3 or 10 μM), not by the ERK or p38 inhibitors. JNK inhibitor abolished the DPQZ-induced increase in the phosphorylation of Bcl-2 and the protein levels of proform caspase-3, caspase-8, and caspase-9, indicating that JNK is an upstream activator of Bcl-2 and caspase family members and plays a key role in DPQZ-induced HSC-3 cell apoptosis. We also attempted to develop an anticancer drug that is designed to kill rapidly dividing cancer cells while causing less damage to normal cells. The DPQZ-induced cytotoxicity against human gingival fibroblasts was less than that against HSC-3 cells. Our work provides a new strategy and mechanism for developing anticancer drug and may contribute to clinical anticancer drug discovery and application.
Archive für Toxikologie 12/2012; · 4.67 Impact Factor
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ABSTRACT: Five new steroidal glycosides (1-5) and nine known compounds were isolated from Solanum violaceum. Indiosides G (1) and H (2) are spirostene saponins with an iso-type F ring, indioside I (3) is a spirostane saponin, and indiosides J (4) and K (5) are unusual furostanol saponins with a deformed F ring. These structures represent rare naturally occurring steroidal skeletons. The structures of the new compounds were elucidated using 1D and 2D spectroscopic techniques and acid hydrolysis. Compounds 2, 3, and 7-9 exhibited cytotoxic activity against six human cancer cell lines (HepG2, Hep3B, A549, Ca9-22, MDA-MB-231, and MCF-7) with IC(50) values of 1.83-8.04 μg/mL. Steroidal saponins 3, 8, and 9 showed inhibitory effects on superoxide anion generation with IC(50) values of 2.84 ± 0.18, 0.62 ± 0.03, and 1.62 ± 0.59 μg/mL, respectively. Saponins 8 and 9 also inhibited elastase release with IC(50) values of 111.05 ± 7.37 and 4.04 ± 0.51 μg/mL, respectively. Structure-activity relationship correlations of these compounds with respect to cytotoxic and anti-inflammatory effects are discussed.
Journal of Natural Products 03/2012; 75(4):636-43. · 3.13 Impact Factor
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ABSTRACT: A series of tetracyclic diterpenoids bearing the α-methylenelactone group have been synthesized and screened for their in vitro anti-tumor activities against six human cancer cell lines. The results showed that compounds 1c, 2a and 2b exhibited significant cytotoxicity superior to the positive control doxorubicin hydrochloride against MDA-MB-231, K562 and HepG2 cell lines. In particular, compound 2b was identified as the most promising anticancer agent against HepG2 cells with IC(50) value of 0.09μM.
Bioorganic & medicinal chemistry letters 03/2012; 22(5):1922-5. · 2.65 Impact Factor
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ABSTRACT: One new sterol, crassarosterol A (1), and four new steroidal glycosides, crassarosterosides A-D (2-5) were isolated from the Formosan soft coral Sinularia crassa. The absolute configuration of 1 was determined using the Mosher's method. The absolute configurations for the sugar moieties of 2-5 were determined by HPLC analysis on the o-tolylthiocarbamates derived from the liberated sugar after acid hydrolysis. Compounds 2 and 4 could significantly inhibit the expression of pro-inflammatory iNOS protein at 10 µM. In contrast, 1-3 were found to stimulate the expression of COX-2 protein at this concentration. Steroids 1 and 4 also showed cytotoxicity toward the selected human liver cancer cells.
Marine Drugs 02/2012; 10(2):439-50. · 3.85 Impact Factor
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ABSTRACT: Melanoma is a lethal form of skin cancer that can metastasize rapidly. While surgery and radiation therapy provide palliative therapy for local tumor growth, systemic therapy is the mainstay of treatment for metastatic melanoma. However, limited chemotherapeutic agents are available for melanoma treatment. In this study, we investigated the anti-melanoma effect of physalin B, the major active compound from a widely used herb medicine, Physalis angulata L. This study demonstrated that physalin B exhibits cytotoxicity towards v-raf murine sarcoma viral oncogene homolog B1 (BRAF)-mutated melanoma A375 and A2058 cells (the IC50 values are lower than 4.6 μg/ml). Cytotoxicity is likely resulted from apoptosis since the apoptotic marker phosphatidylserine are detected immediately under physalin B treatment and apoptotic cells formation. Further examination revealed that physalin B induces expression of the proapoptotic protein NOXA within 2 h and later triggers the expression of Bax and caspase-3 in A375 cells. These results indicate that physalin B can induce apoptosis of melanoma cancer cells via the NOXA, caspase-3, and mitochondria-mediated pathways, but not of human skin fibroblast cells and myoblastic cells. Thus, physalin B has the potential to be developed as an effective chemotherapeutic lead compound for the treatment of malignant melanoma.
Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 01/2012; 50(3-4):619-24. · 2.99 Impact Factor
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ABSTRACT: Further investigation of the methanolic extract of Fissistigma latifolium resulted in two new compounds whose structures were assigned as 2,5,6,7-tetramethoxyflavan (1) and 2'-hydroxy-4',5',6'-trimethoxybenzil (2). These two compounds were determined on the basis of chemical and spectroscopic evidences. Compound 2 is the first report of benzil from Fissistigma species. 2,5,6,7-Tetramethoxyflavan (1) showed a potent inhibitory effect on superoxide anion production in formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP)/cytochalasin B (CB)-activated human neutrophils.
Chemical & pharmaceutical bulletin 01/2012; 60(2):280-2. · 1.70 Impact Factor
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ABSTRACT: Toona sinensis Roem (T. sinensis) leaves have been used as a nutritious vegetable and been suggested for medical applications; however, the reported bioactive compounds of T. sinensis leaves are, so far, from high to mid-high polar extracts. Our aims in this study were to reveal the non-polar constituents of the T. sinensis leave extract that were prepared by a method of using a supercritical-CO2 fluid and to investigate the anti-diabetic potential of this extract. Through a GC/MS analysis, we revealed 24 major components of the non-polar T. sinensis leave extract, the most abundant of which was phytol. The non-polar T. sinensis leave extract showed to prevent the progression of diabetes and hepatosteatosis, the rise of triglycerol levels and the decrease of adiponectin levels in the type 2 diabetic mice. Our results suggest that the non-polar extract of T. sinensis leaves prepared using the supercritical-CO2 fluid may contain effective constituents to prevent type 2 diabetes.
Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 12/2011; 50(3-4):779-89. · 2.99 Impact Factor
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Yang-Chang Wu,
Jui-Hsin Su,
Tai-Ting Chou,
Yin-Pin Cheng,
Ching-Feng Weng,
Chia-Hung Lee,
Lee-Shing Fang,
Wei-Hsien Wang,
Jan-Jung Li,
Mei-Chin Lu,
Jimmy Kuo,
Jyh-Horng Sheu,
Ping-Jyun Sung
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ABSTRACT: The structures, names, bioactivities, and references of 81 new secondary metabolites obtained from gorgonian corals belonging to the genus Junceella are described in this review. All compounds mentioned in this review were obtained from sea whip gorgonian corals Junceella fragilis and Junceella juncea, collected from the tropical and subtropical Indo-Pacific Ocean.
Marine Drugs 12/2011; 9(12):2773-92. · 3.85 Impact Factor
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ABSTRACT: Microtubules are a proven target for anticancer drug development because they are critical for mitotic spindle formation and the separation of chromosomes at mitosis. 2-(Naphthalene-1-yl)-6-pyrrolidinyl-4-quinazolinone (HL66) induced cell death with the large cells and multiple micronuclei in M21 skin cancer cells. We demonstrated that HL66-induced cell death is caspase-independent and accompanied by the failure of cell cycle progression. Therefore, HL66-induced cell death may be a mitotic catastrophe. HL66 inhibits the dephosphorylation on Thr14 or Tyr15 of cyclin-dependent kinase (Cdk) 1 and the formation of Cdk1/cyclin B1 complex, which might be associated with cell cycle arrest at the S and G(2)/M phases. HL66 is an antimicrotubule agent by molecular modeling on the basis of ligand binding to tubulin molecule. Furthermore, we also demonstrated that HL66, like vinblastine, is a tubulin-destabilizing agent via microtubule disruption in M21 cells. These results describe a novel pharmacological property of HL66 as a microtubule inhibitor, which may make it an attractive new agent for the treatment of skin cancer.
Journal of Pharmacology and Experimental Therapeutics 06/2011; 338(3):942-51. · 3.83 Impact Factor
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ABSTRACT: Photodynamic therapy was found to be an effective therapy for local malignant tumors. This study demonstrated that 80 μg/ml Hedyotis corymbosa extracts with 0.8 J/cm(2) fluence dose caused M21 skin cancer cell death. Photoactivated H. corymbosa-induced M21 cell death is a typical apoptosis that is accompanied by nuclear condensation, externalization of phosphatidylserine and the changes in protein expression of apoptosis-related proteins, such as Bcl-2 and caspase family members. This study applied 2D electrophoresis to analyse the proteins involved in the photoactivated H. corymbosa-induced M21 cell apoptosis. We found 12 proteins to be markedly changed. According to the results of protein sequence analysis of these altered protein spots, we identified that the expression of cytoskeletal proteins and chaperones were involved in the photoactivated H. corymbosa-induced M21 cell apoptosis. We further demonstrated that photoactivated H. corymbosa caused a significant effect on the cytoskeleton distribution and mitochondrial activity in M21 cells. Based on the above findings, this study characterized the effects and mechanisms of the photoactivated H. corymbosa-induced apoptosis in M21 skin cancer cells.
Experimental Dermatology 05/2011; 20(8):653-8. · 3.54 Impact Factor
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ABSTRACT: This study demonstrated that many apoptotic signaling pathways, such as Rho family, PKC family, MAP kinase family, and mitochondria-mediated apoptotic pathway, were triggered by Lonicera japonica extracts and irradiation in CH27 cells. Rottlerin, a PKCδ -selective inhibitor, reversed the photoactivated Lonicera japonica extract-induced decrease in PKCδ protein expression and change in cell morphology in this study. In addition, rottlerin inhibited the photoactivated Lonicera japonica-induced decrease in protein expression of Ras, ERK, p38, PKCα, and PKCε, which are the kinases of prosurvival signaling pathway. We also demonstrated that pretreatment with rottlerin prevented actin microfilaments and microtubules from damage during the photoactivated Lonicera japonica-induced CH27 cell death. Furthermore, the promotion of the cytoskeleton-related signaling cascade following rottlerin by upregulation of cytoskeleton-related mediators (p38, HSP27, FAK, paxillin, and tubulin) and molecules of downstream of F-actin (mitochondria-mediated apoptosis pathway) reduces CH27 cell death, indicating that cytoskeleton is the potential target in the photoactivated Lonicera japonicaextract-induced photokilling of CH27 cells.
Evidence-based Complementary and Alternative Medicine 01/2011; 2011:193842. · 4.77 Impact Factor