Antiproliferation Activity and Apoptotic Mechanism of Soursop (Annona muricata L.) Leaves Extract and Fractions on MCF7 Breast Cancer Cells

Introduction: Breast cancer is the second most common cancer in women globally, and the incidence rate has increased annually. Traditional medicine is frequently used as a cancer treatment, and soursop or Annona muricata L (A. muricata) is a traditional medicinal plant that has been widely used as an anticancer treatment and requires more thorough study. Methods: In this research, we prepared ethanol extract and three solvents, ie, ethyl acetate, n-hexane and water fractions of A. muricata leaves and assessed their antiproliferation and cytotoxic activity on MCF7 breast cancer cells compared with that on CV1 normal kidney cells; observation of cell morphology by stained with mixture of propidium iodide and 4',6-diamidino-2-phenylindole indicated that this treatment induced an ongoing process of apoptotic cell death in MCF7 cells. To clarify the cell death mechanism via apoptosis, we assessed the mRNA expression in the caspase cascade of caspase-9, caspase-3, and PARP-1, and anti-apoptotic, Bcl-2 which mediated cytotoxic activity of extracts and ethyl acetate fractions of A. muricata leaves against MCF7 cells. Results: The ethanol extract, ethyl acetate, n-hexane, and water fractions of A. muricata leaves had IC50 values of 5.3, 2.86, 3.08, and 48.31 mu g/mL, respectively, in MCF7 cells but had no activity in CV1 cells. The high cytotoxic activity of A. muricata leaves was reflected by changes in the morphology of cancer cells that appeared after 6 h exposure to A. muricata leaf extract and ethyl acetate fraction; the membrane and nucleus of cells undergoing apoptosis were characterized by the rupture and loss of membranes and nuclei. The mechanism that mediates this cytotoxic activity in MCF7 cells was mediated through a decrease in the expression of Bcl-2 mRNA and an increase in caspase-9 and caspase-3 mRNA expression. Conclusion: Therefore, the leaves of the medicinal plant A. muricata contained compounds that on extraction exerted a highly effective activity as an anticancer treatment for breast cancer via induced apoptotic cell death.