Root Extract of a Micropropagated Prunus africana Medicinal Plant Induced Apoptosis in Human Prostate Cancer Cells (PC-3) via Caspase-3 Activation

Abstract

Prostate cancer is one of the major causes of cancer-related deaths among men globally. Medicinal plants have been explored as alternative treatment options. Herein, we assessed the <i>in vitro</i> cytotoxic effects of 70% ethanolic root extracts of six-month-old micropropagated <i>Prunus africana</i> (PIR) on PC-3 prostate cancer cells as an alternative to the traditionally used <i>P. africana</i> stem-bark extract (PWS) treatment. <i>In vitro</i> assays on PC-3 cells included annexin-V and propidium iodide staining, DAPI staining, and caspase-3 activity analysis through western blotting. PC-3 cells were exposed to PWS and PIR at different concentrations, and dose-dependent antiprostate cancer effects were observed. PC-3 cell viability was determined using CCK-8 assay, which yielded IC₅₀ values of 52.30 and 82.40 <i>μ</i>g/mL for PWS and PIR, respectively. Annexin-V and PI staining showed dose-dependent apoptosis of PC-3 cells. Significant (<i>p</i> < 0.001) percent of DAPI-stained apoptotic PC-3 cells were observed in PWS, PIR, and doxorubicin treatment compared with the negative control. PWS treatment substantially elevated cleaved caspase-3 levels in PC-3 cells compared with the PIR treatment. These results provide evidence for the antiprostate cancer potential of PIR and sets a basis for further research to enhance future utilization of roots of young micropropagated <i>P. africana</i> for prostate cancer treatment as an alternative to stem bark. Moreover, micropropagation approach may help provide the required raw materials and hence reduce the demand for <i>P. africana</i> from endangered wild population.