409 NATURAL COMPOUND ALTERNOL ACTIVATES APOPTOSIS AND AUTOPHAGY IN PROSTATE CANCER CELLS

Abstract

You have accessJournal of UrologyProstate Cancer: Basic Research1 Apr 2011409 NATURAL COMPOUND ALTERNOL ACTIVATES APOPTOSIS AND AUTOPHAGY IN PROSTATE CANCER CELLS Andrew James, Benyi Li, and Jeffrey Holzbeierlein Andrew JamesAndrew James Kansas City, KS More articles by this author , Benyi LiBenyi Li Kansas City, KS More articles by this author , and Jeffrey HolzbeierleinJeffrey Holzbeierlein Kansas City, KS More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.498AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Alternol is a natural product derived via fermentation from the microorganism Alternaria Alternata from the bark of a yew tree native of China. In human gastric cancer cell lines and in some prostate cancer cell lines, Alternol has been shown to induce apoptosis. We sought to evaluate the potential for Alternol to induce cell death in prostate cancer cell lines and to more specifically investigate the mechanisms by which Alternol induces apoptosis and cell death. We examined the in vitro effects of Alternol in several different prostate cancer cell lines. METHODS Three prostate cancer cell lines (LNCaP, C4-2, and PC-3) were treated with Alternol. Cell viability was assessed via trypan blue exclusion assay and the cell cycle distribution of each of these lines was also examined after culturing each of these lines with and without Alternol. Intracellular concentrations of autophagy and apoptotic regulatory proteins were determined via Western blotting by utilizing antibodies against caspase-3, PARP, Bcl-2, and Bax following treatment with Alternol. Cells were also treated with the antimalarial Choloroquine (an inhibitor of autophagy) to further examine the effects of Alternol on autophagy and apoptotic pathways. RESULTS Alternol, in both androgen dependent and independent cell lines, induced cell arrest at G2/M at 24 hours. Alternol also induced cytotoxicity at 12 hours post-treatment. In all 3 cell lines, apoptosis occurred by caspase-3 processing and PARP cleavage. Additionally, Bcl-2 expression was significantly lowered and Bax protein expression was increased in cell lines treated with Alternol, suggesting that Alternol targets expression of these proteins in promoting apoptosis. Bif-1, a regulator of both apoptosis and autophagy, was found to be up-regulated by Alternol. LC-3II levels were also up-regulated in Alternol treated cells. Blocking autophagy with Choloroquine enhanced Alternol caspase-3 processing and PARP cleavage and enhanced apoptosis and synergistically promoted cytotoxicity. CONCLUSIONS Alternol is capable of inducing apoptotic cell death in prostate cancer cells through modulation of pro- and anti-apoptotic proteins. This novel natural compound deserves further examination and validation in in-vivo models. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e165 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Andrew James Kansas City, KS More articles by this author Benyi Li Kansas City, KS More articles by this author Jeffrey Holzbeierlein Kansas City, KS More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...