In Vitro Anti-Proliferative Activity of Selected Plant Extracts Against Cervical and Prostate Cancer Cell Lines

Abstract

Prostate and cervical cancers are among the leading cancers in men and women respectively. In 2012 the world health organization reported an estimated 266,000 deaths from cervical cancer worldwide, while 1.1 million men worldwide were diagnosed with prostate cancer. The current conventional cancer therapies, chemotherapy and radiotherapy, present severe side effects and in many developing countries are inaccessible to many cancer patients. The alternative traditional medicine offers the much-needed hope. This study investigated the antiproliferative activity of methanolic and water extracts from four plant species namely Aloe secundiflora, Maytenus obscura, Vernonia zanzibarensis and Dichrostachys cinerea using prostate cancer cells (DU145 and 22Rv1), cervical cancer cells (HeLa) and African green monkey cells (Vero) cell lines using the MTT assay. All extracts suppressed the growth of the cancer cells in a dose-dependent manner at concentrations of 1.37 µg/ml to 1000 µg/ml. The methanol extract of D. cinerea stem bark had the highest anti proliferative activity among the plant extracts studied with an IC50 of 8.04 ± 2.02 µg/ml against the 22Rv1 cells and a low cytotoxic effect against the Vero cells with CC50 of 812.1 ± 12.72 µg/ml. The study indicates that the methanol extract of D. cinerea stem bark has potential anti-proliferative activity with low cytotoxicity to normal cells. Our results validate the ethnomedicinal use of these plants for management of cancer. The active elements in the extracts studied here need to be isolated and purified to investigate the synergy and additive pharmacological effect in killing cancer cells.