Assessment of cytotoxic effects of Prunus Africana extracts on prostate cancer C4-2 cells in vitro

Phytochemicals from secondary plant metabolism exhibit notable biological activities, including antioxidant and anticarcinogenic effects. This study evaluated the cytotoxic potential of Prunus africana extracts on prostate cancer cells in vitro. Bark, leaf, and root samples were extracted using absolute methanol or ethanol, and assessed for total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity. Cytotoxicity was tested using the MTS cell viability assay on C4-2 cells, a hormonally insensitive subline of LNCaP, and primary prostate epithelial cells over 6, 12, and 24 h. Additional cellular assays were carried out to determine whether the expected cell death mechanism occurred via apoptosis or necrosis. The bark methanolic extract showed the highest TPC (1397.33 mg GAE/g) and the lowest EC50 value (0.10 mg/mL), comparable to ascorbic acid (0.18 mg/mL). The bark methanolic extract also exhibited a concentration-dependent cytotoxic effect between 0.000025 and 0.25 mg/mL, with selective toxicity at 0.025 mg/mL toward C4-2 cells compared to the primary prostate epithelial cell line tested. Cellular and molecular assays indicated that apoptosis was the primary mechanism of cell death. These results suggest that P. africana bark methanolic extract is a promising candidate for treating hormonally insensitive prostate cancer.