Cantharidin suppresses HCT116 colorectal carcinoma cell proliferation and migration by changing the cytoskeleton structure

Abstract

Background: Cantharidin (CTD), a natural toxin produced from Chinese blister beetles, has extensive anti-tumor activity. The present study investigated the effect of CTD on a human colon cancer cell line to elucidate potential new insights regarding the mechanism(s) through which CTD exerts its anti-tumor effects. Materials and methods: The inhibitory effect of CTD on human colon cancer HCT116 cells was evaluated using the IncuCyte ZOOM™ analyzer. Apoptotic cells were detected by Annexin V-FITC/PI assay and cell cycle was evaluated with flow cytometry following propidium iodide staining. Alterations in F-actin microfilaments were analyzed by FITC-phalloidin staining and morphological changes were evaluated with a laser scanning confocal microscope. Cell migration assay was carried out to investigate the effects of CTD on migration of HCT116 cells in vitro. Results: CTD exhibited a significant growth inhibitory effect on HCT116 cells accompanied by an increase in G2/M phase cells, without a significant effect on apoptosis. CTD-treated cells also exhibited a dramatic collapse in their microfilament network and a significant reduction in cell adhesion. Conclusion: CTD inhibits growth by increasing G2/M phase cells and decreasing S phase cells, revealing that CTD exerts a significant growth inhibitory effect primarily through an inhibition of cell cycle progression (a cytostatic effect). Moreover, a negative effect on cell migration may also constitute a contributing factor to its anti-tumor potential. These findings suggest the potential use for developing CTD as a novel anti-cancer therapy that targets metastasis Giving full play to CTD may inhibit tumor transfer. Keywords: Cantharidin, Actin cytoskeleton, Cell adhesion, Proliferation, Migration