BG-4, a bioactive peptide from Momordica charantia, promotes apoptosis in ovarian cancer cells

Momordica charantia is a perennial plant with reported health benefits. Food-derived molecules, like the novel peptide BG-4 found in Momordica charantia, have been shown to have anticancer properties by promoting apoptosis in colon cancer cells. Ovarian cancer (OVCA) is the deadliest form of all gynecological cancers. The high fatality rate of OVCA is due to late presentation of the disease, cancer persistence, and recurrence in patients. The objective of this study was to determine the ability of BG-4 to cause cytotoxicity to ovarian cancer cells (A27801AP and COV318) and determine the mechanism involved by measuring proteins associated with apoptosis. BG-4 treatment caused a decrease in viable cell count by 65.1% at 250 μg/mL (A27801AP) and 19.8% at 250 μg/mL (COV318). The mechanism involved in the decrease in viable cell count is due to promoted apoptosis as evidenced by increased percentage of A27801AP undergoing apoptosis from 7.1% (untreated) to 23.9% (BG-4 treated, 250 μg/mL). The molecular mechanism explanation for the induced apoptosis of ovarian cancer cells due to BG-4 is caused by the increase in expression of pro-apoptotic marker BAX while reducing expression of anti-apoptotic marker XIAP. This led to an increase in expression of capsase-3 and caused an affect on the expression of cell cycle proteins p21 and CDK2. These findings support the hypothesis that there is anti-cancer potential for the BG-4 peptide isolated from Momordica charantia in vitro against ovarian cancer and should be further addressed using in vivo models of ovarian carcinogenesis.