Growth Inhibitory and Pro-Apoptotic Effects of Ornamental Pomegranate Extracts in Du145 Human Prostate Cancer Cells

Abstract

Aims: Prostate cancer is the most common form of cancer in the male. Epidemiological studies have associated increased cancer incidence with reduced consumption of fruit and vegetables. This study was aimed to investigate the influence of dwarf pomegranate extracts (peel, juice, and seeds oil) on the proliferation and apoptosis of human prostate androgen-independent cell line DU145. Methods: The cell viability was determined by the MTT assay. Morphological changes are detected by light microscopy. The ELISA assay is used to evaluate the nuclear DNA fragmentation and western Blot to detect the expression of apoptosis-associated proteins including poly-ADP-ribose polymerase (PARP) and cyclooxygenase-2 (COX-2). Results: The three tested extracts exhibited a dose-response cytotoxic effect and antiproliferative action on DU145 cell line and induce morphological changes. The dose of each extract required to inhibit cell proliferation by 50% (IC50) was 0.12, 0.36, and 0.42 mg/mL, respectively, for seeds oil, juice, and peel. The three extracts could also induce prostate cancer cell apoptosis by an increase of DNA fragmentation, PARP cleavage, and inhibition of the COX-2 expression. The strongest pro-apoptotic effect was shown after peel treatment. Conclusion: Dwarf pomegranate extracts exhibited potent growth inhibitory activities in human prostate cancer cells (DU145), which appear to be mediated by a pro-apoptotic mechanism.