Correlation of IGFBP-6 expression with apoptosis and migration of colorectal carcinoma cells

Colorectal cancer (CRC) is one of the most common malignant tumors in digestive tract. Previous study found close correlation between insulin-like growth factor binding proteins (IGFBPs) and occurrence of multiple tumors. This study aims to analyze the effects of IGFBP6 on the apoptosis and migration of tumor cells, and to investigate underlying mechanism. HCT-116 or SW480 cell was cultured with 1.0 mg/l, 10 mg/l and 100 mg/l IGFBP-6. MTT assay was employed to test the proliferation activity of tumor cells after differential treatment. The cell cycle of tumor cells was detected by flow cytometry, while Transwell assay was used to quantify the invasion and migration of tumor cells after IGFBP-6 intervention. In experimental group with IGFPB-6 application, the proliferation rate of HCG-116 or SW480 cells was gradually decreased with higher concentrations of IGFBP-6 (p< 0.05). The ratio of cells at G0/G1 phase was increased while S phase and G2/M phase ratio were all decreased with IGFPB-6. With further elevated concentration of IGFPB-6, there was more potency of higher G0/G1 ratio and lower S phase or G2/M phase (p< 0.05). Both invasion and migration ability of HCT-116 or SW480 cells in experimental group were decreased. With elevated IGFBP-6 concentration, cell invasion and migration were further weakened (p< 0.05).IGFBP-6 could inhibit invasion and migration of colorectal carcinoma cells possibly via inhibiting proliferation activity and arresting cell cycle of HCT-116 or SW480 cells.