title: Involvement of the mitochondrial pathway in bruceine D-induced apoptosis             in Capan-2 human pancreatic adenocarcinoma cells.
abstract: The fruit of Brucea javanica L. is a common herb used in Chinese medicine for the treatment of a variety of cancers. Our research group has previously identified bruceine D (BD), a quassinoid found abundantly in B. javanica, to have potent cytotoxic effect on a number of pancreatic cancer cell lines, including Panc-1, SW1990 and Capan-1 cells. In the present study, we showed that BD was also able to inhibit the growth of the Capan-2 human pancreatic adenocarcinoma cell line, but it exerted only modest cytotoxicity on the WRL68 human hepatocyte cell line and a human pancreatic progenitor cell line. The antiproliferative effects of BD were comparable to those exhibited by camptothecin and gemcitabine in our culture system. We found a dose-dependent decrease of the mitochondrial membrane potential in BD-treated Capan-2 cells as measured by the JC-1 assay. BD exposure was able to attenuate the expression of Bcl-2 protein in Capan-2 cells as detected by western blot analysis. In addition, the expression of both caspase 9 and caspase 3 in BD-treated Capan-2 cells was significantly accentuated. Moreover, BD was capable of inducing the fragmentation of genomic DNA in Capan-2 cells as evidenced by Hoechst staining. Cell cycle analysis demonstrated that BD could increase the percentage of Capan-2 cells in the subG1 phase in a dose-related manner. An increase in the apoptosis of Capan-2 cells was also observed by Annexin V and PI staining. These results unequivocally indicate that BD induces cytotoxicity in Capan-2 cells via the induction of cellular apoptosis involving the mitochondrial pathway.
authors.affiliation: School of Chinese Medicine, Faculty of Science, The Chinese University                     of Hong Kong, Shatin, NT, Hong Kong SAR, P.R. China.
authors.forename: Ling
authors.initials: L
authors.lastname: Liu
authors.forename: Zhi-Xiu
authors.initials: ZX
authors.lastname: Lin
authors.forename: Po Sing
authors.initials: PS
authors.lastname: Leung
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: Chen
authors.forename: Ming
authors.initials: M
authors.lastname: Zhao
authors.forename: Juan
authors.initials: J
authors.lastname: Liang
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D032269:Brucea; D002166:Camptothecin / Q000494:pharmacology; D053148:Caspase 3 / Q000096:biosynthesis; D053453:Caspase 9 / Q000096:biosynthesis; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004249:DNA Damage / Q000187:drug effects; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000494:pharmacology; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D022781:Hepatocytes / Q000187:drug effects; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D036702:Quassins / Q000494:pharmacology*; D013234:Stem Cells / Q000187:drug effects; D000093542:Gemcitabine
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004365:Drugs, Chinese Herbal; D019253:Proto-Oncogene Proteins c-bcl-2; D036702:Quassins; D003841:Deoxycytidine; C030412:bruceine D; D053148:Caspase 3; D053453:Caspase 9; D002166:Camptothecin; D000093542:Gemcitabine