Anti-proliferative Activity of Vitex negundo Leaf Extracts on PA1 Human Ovarian Cancer Cell Lines

In Ayurveda, Vitex negundo (VN) is used as a drug to manage pain, inflammation, and problems related to polycystic ovary disease and the menstrual cycle. The bioactive compounds isolated from this plant exhibit anti-inflammatory, anti-oxidant, anti-cancer, and microbicidal properties. The shrub VN is known for its role in the modulation of cellular events like apoptosis and cell cycle. There is still a scarcity of data in the literature on the cytotoxic activity of VN extracts on ovarian cancer. Therefore, in the present study, the phytochemical composition, anti-oxidant, and anti-cancer activities of leaf extracts were evaluated. The chloroform and methanol fractions exhibited higher phenolic content (161.04 ± 0.02 mg/g GAE and 152.56 ± 0.05 mg/g GAE, respectively) than those of other fractions. The aqueous and petroleum ether fractions exhibited higher flavonoid content (215.27 ± 0.28 mg/g QE and 111.82 ± 0.05 mg/g QE, respectively). The acetone and methanol extracts showed significant anti-oxidant capacities. Both leaf extracts of VN inhibited PA1 cancer cell growth in a dose-dependent manner with IC₅₀ values of 88.01 ± 3.14 and 112.30 ± 1.93 μg/ml, respectively, as compared to the standard drug Doxorubicin with IC₅₀ value 2.91 μg/ml (P<0.05, One-way ANOVA). The gas chromatography-mass spectroscopy (GC-MS) analysis allowed us to identify twenty-five bioactive compounds in acetone extract and twenty-two in methanol extract. Therefore, further studies should focus on the isolation of novel compounds that are more effective and less toxic, and that constitute interesting substitutes for the development of anti-cancer drugs.