In vitro pro-apoptotic and anti-migratory effects of Treculia africana Decne. (Moraceae) and Entandrophragma angolense Welw (Meliaceae) extracts on prostate cancer cells

Prostate cancer is the second leading cause of cancer deaths in men and there is an increasing interest in chemoprevention to fight it. The authors sought a scientific rationale for the traditional use of six Cameroonian medicinal plants for the treatment of prostate inflammation/tumour. The prostate cells viability incubated with each ethanolic plant extract was determined after 24, 48 and 72 h using the MTT assay. The antitumor mechanisms of promising extracts [Treculia africana (TA) and Entandrophragma angolense (EA)] were further assessed by evaluating cell growth, cell proliferation, cell cycle, cell death mechanisms and cell migration. Only TA and EA significantly inhibited LNCaP, DU145 and PC3 prostate carcinoma cells growth and proliferation at the optimal concentrations (20–50 μg/mL). Furthermore, they significantly increased the number of apoptotic cells in PC3 cells at 20 μg/mL, while only TA significantly increased the number of G0/G1 cells in both DU145 and PC3 at 50 μg/mL. Cell cycle proteins (pcdk1, cdk2, pcdk2) were down-regulated by TA in both DU145 and PC3 cells. EA induced an overexpression of caspase-3 in both tested cells; meanwhile it induced an underexpression of cdk2. Apoptosis-related proteins Akt, pAkt and Bcl-2 were down-regulated in both DU145 and PC3 cells while caspase-3 was up-regulated following treatment with EA and TA. TA and EA inhibited cell chemotaxis and migration, while it increased cell adhesion to a fibronectin matrix. Taken altogether, these findings suggest that Treculia africana and Entandrophragma angolense might contain phyto-constituents which can be a promising strategy for the treatment of prostate cancer.