Antiproliferation activity againts prostate cancer cells PC-3 by Thai rejuvenating herbs

Abstract

The antiproliferation activity potential of ethanolic crude extracts obtained from 22 traditional Thai rejuvenating herbal plants against PC-3 (human prostate cancer) cells were evaluated. The PC-3 cells were incubated with plant crude extracts for 72 h prior to MTT assay in comparison with the DMSO and genistein control. There were three ethanolic crude extracts with the strong antiproliferation activity including S. erecta, S. venosa and S. asper with IC₅₀ values of 4.30, 4.47 and 10.78 μg/ml, respectively. The ethanolic crude extracts showed antiproliferation against PC-3 cells via apoptosis induction when confirmed by the flow cytometry with annexin V-FITC/propidium iodide double staining. Immunoblotting analysis was confirmed for apoptosis-related proteins at 48 h incubation period which resulted in underexpression of anti-apoptotic Bcl-2, overexpression of pro-apoptotic Bax, overexpression of caspase-3 and cleavage of poly (ADP-ribose) polymerase (PARP). The protein expression levels were studied with two-dimensional (2-DE) gel electrophoresis. The differential protein expressions were identified with LC/MS/MS along with Mascot search engine and confirmed with immunoblotting. PC-3 cells treated with the 3 plant ethanolic crude extracts exerted differences in protein expression in comparison with the control. The 14-3-3 protein in PC-3 cells was down-regulated in all treatment and thus might be considered as diagnostic markers or as therapeutic targets for prostate cancer. Besides, the 78 kDa glucose-regulated protein, annexin A5 and tropomyosin alpha-3 chain are possible to be novel prostate cancer marker candidates. The study demonstrates the high potential of certain Thai rejuvenating herbal plant against the prostate cancer cells.