Anti-proliferative effect of the chloroform extract of Annona squamosa leaves in HepG2 cancer cell lines

Liver cancer is a leading cause of death in Africa. The incidence and mortality for liver (hepatic) cancer is increasing at an alarming rate in sub-Saharan Africa. This situation is compounded by a lack of standard and satisfactory treatment method for hepatic cancer. Therefore, the current study was designed to investigate the effect of the Annona squamosa leaf extract on the in vitro proliferation of liver cancer cells. The extracts of the leaves of A. squamosa were screened via MTT assays with liver (HepG2) and cervical (Hela) cancer cell lines. The mechanism of action of leaf extract of A. squamosa in HepG2 cancer cell lines were investigated via caspases 3, 8 and 9 proteins assay as well as gene expression analysis. The chloroform extract of the leaves was the most cytotoxic with an IC50 of 7.5 ± 1.46 µg/ml. The chloroform extract significantly increased the expressions of caspase-3, -8 and -9 proteins in the HepG2 cells. Furthermore, the extract significantly upregulated P53, P27, bax and cytochrome c genes and downregulated the MDM2 and bcl-2 genes in the HepG2 cells. The expression of cytochrome c gene was over 30 folds suggesting the involvement of the mitochondrial pathway in the apoptosis of HepG2 cancer cell lines. Therefore, the chloroform extract of the leaves of A. squamosa can be potentially used as an anti-liver cancer agent.