Ginkgolic acid inhibits the invasiveness of colon cancer cells through AMPK activation

Tumor cell invasion and metastasis are important processes in colorectal cancer that exert negative effects on patient outcomes; consequently, a prominent topic in the field of colorectal cancer study is the identification of safe and affordable anticancer drugs against cell invasion and metastasis, with limited side effects. Ginkgolic acid is a phenolic acid extracted from ginkgo fruit, ginkgo exotesta and ginkgo leaves. Previous studies have indicated that ginkgolic acid inhibits tumor growth and invasion in a number of types of cancer; however, limited studies have considered the effects of ginkgolic acid on colon cancer. In the present study, SW480 colon cancer cells were treated with a range of concentrations of ginkgolic acid; tetrazolium dye-based MTT, wound-scratch and transwell migration assays were performed to investigate the effects on the proliferation, migration and invasion of colon cancer cells, and potential mechanisms for the effects were explored. The results indicated that ginkgolic acid reduced the proliferation and significantly inhibited the migration and invasion of SW480 cells in a concentration-dependent manner. Additional experiments indicated that ginkgolic acid significantly decreased the expression of invasion-associated proteins, including matrix metalloproteinase (MMP)-2, MMP-9, urinary-type plasminogen activator and C-X-C chemokine receptor type 4, and activated adenosine monophosphate activated protein kinase (AMPK) in SW480 cells. Small interfering RNA silencing of AMPK expression reversed the effect of ginkgolic acid on the expression of invasion-associated proteins. This result suggested that ginkgolic acid inhibited the proliferation, migration and invasion of SW480 colon cancer cells by inducing AMPK activation and inhibiting the expression of invasion-associated proteins.