Activation of farnesoid X receptor by GW4064 inhibits invasive growth of colon cancer cells and expression of stromal cell-derived factor 1 / 第二军医大学学报

ABSTRACT

Objective To explore the mechanism by which specific agonist of farnesoid X receptor (FXR) GW4064 inhibits the growth and invasion of colon cancer cells. Methods Human colon cancer cell lines HT-29 were in vitro cultured. After treatment with GW4064 of 0, 0.1, 1, 3, 5, 7 and 10 μmol/L for 72 h, cell viability was measured by MTT assay. After treatment with GW4064 of 0, 1 and 5 μmol/L for 24 h, the cell morphology was observed under phase contrast microscope, and the mRNA expression levels of FXR and stromal cell-derived factor 1 (SDF-1) were detected by PCR. After treatment with GW4064 of 0 and 1 μmol/L for 24 h, the cell invasive ability was detected by cell scratch test. After treatment with GW4064 of 0, 1, 5 and 7 μmol/L for 24 h, the SDF-1 expression in the culture medium was detected by ELISA. Nude mouse. tumorigenesis model was established by subcutaneous inoculation of HT-29 cells. After intragastric administration with GW4064 or DMSO for 16 d, the tumor growth and the mRNA expression of FXR and SDF-1 in the tumors were determined. ResultsGW4064 inhibited the growth of HT-29 cells in a dose-dependent manner, and there was significant difference in the cell viability of HT-29 cells between the GW4064 groups (1, 3, 5, 7 and 10 μmol/L) and the control group (0 μmol/L, all P<0.05). After treatment with GW4064, phase contrast microscopy showed contracted and rounded colon cancer cells and slender cells transforming into epidermoid cells. The cell scratch test showed that the invasion ability of the colon cancer cells was significantly reduced after treatment with GW4064 compared with the control group (0 μmol/L, P<0.05). PCR results showed that the mRNA expression level of FXR was increased in a dose-dependent manner after GW4064 treatment, while the expression of SDF-1 mRNA changed in the opposite way. ELISA results showed that the SDF-1 expression in the cell culture supernant was decreased with the increase of GW4064 concentrations, and there were significant differences between the GW4064 (1, 5 and 7 μmol/L) groups and the control group (0 μmol/L, P<0.05). GW4064 significantly reduced tumor size compared with the control group (DMSO, P<0.05). In addition, the mRNA expression of FXR in the tumors was increased, and the mRNA expression of SDF-1 was decreased. ConclusionThe activation of FXR can inhibit the invasive growth of colon cancer cells and the expression of SDF-1.