Molecular mechanisms of apoptosis induction in KG1a leukemia cells by the Ginkgo biloba extract (EGb)

Ginkgo biloba is a traditional medicinal herb with anti-cancer, anti-viral, anti-inflammatory, and liver protective properties. In here, we investigated several variables related to Ginkgo biloba extract (EGb)-induced apoptosis in human acute myeloid leukemia KG1a cells. The MTT method was used to quantify cell survival. Following Hoechst 33,258 staining, an inverted microscope to examine the appearance of apoptotic cells was used. Furthermore, to determine the ratio of necrotic to apoptotic cells, annexin V-FITC, propidium iodide (PI) double staining was performed. Using flow cytometry analysis, alterations in the cell cycle were examined. Using the appropriate reagent kits, the activities of caspase-3 was examined. Alterations in multiple apoptosis-associated gene expression were evaluated using a quantitative real-time PCR technique. The MTT results demonstrated that EGb dramatically and dose-dependently reduced the viability of KG1a cells. EGb causes KG1a cells to contract and produce more apoptotic bodies according to observations of their morphology. According to cell cycle studies, EGb arrested the cells in the S phase of cell cycle. The validity of the cell cycle data was confirmed by the decrease in cyclin A expression, and the increase in the expression of p53, p21, cyclin E, and CDK2. qRT-PCR analysis revealed that EGb induces apoptosis by reducing Survivin, raising Noxa, and causing a time-dependent increase in Bax/Bcl-2 transcript. These results suggest EGb induces cell death, potentially offering a promising treatment approach for acute myeloid leukemia.