Effects and its mechanism of silencing Galectin-3 gene expression by small interfering RNA on proliferation and apoptosis of cholangiocarcinoma cells

Abstract

Objective To study the effect and mechanism of inhibition of Galectin-3 gene expression on proliferation and apoptosis of cholangiocarcinoma cells. Methods The mRNA and protein expression of Galectin-3 gene in cholangiocarcinoma were detected by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting; small interfering RNA (siRNA)-Galectin-3 was transfected into HCCC-9801 cells, and cells transfected with negative control group and normal control group, the expression of Galectin-3, Ki-67, Cleaved Caspase-3, β-catenin, Cyclin D1 protein were detected by Western blotting after 48 h; CCK-8 assay and flow cytometry were used to detect the proliferation and apoptosis of cell. Results The mRNA (5.558±0.056)and protein (0.269±0.025)expression of Galectin-3 gene in cholangiocarcinoma was significantly higher than that in adjacent tissues (0.977±0.031) and (0.037±0.011) (tmRNA=8.626, PmRNA=0.003; tProtein expression=8.997, PProtein expression=0.002); protein expression of Galectin-3 (0.094±0.012), Ki-67(0.201±0.025), β-catenin (0.261±0.024), Cyclin D1 (0.137±0.017) and cell survival rate (95.26±3.42)% in si-Galectin-3 group was significantly lower than that of Normal group [(0.358±0.031)%, (0.426±0.032)%, (0.894±0.047)%, (0.435±0.031)%, (71.12±4.48)%] (tGalectin-3=9.007, PGalectin-3=0.002; tKi-67=8.138, PKi-67=0.003; tβ-catenin=9.345, Pβ-catenin=0.002; tCyclin D1=9.977, PCyclin D1=0.001; tcell survival rate=8.452, Pcell survival rate=0.003); the apoptosis rate (17.12±1.28)% and Cleaved Caspase-3 (0.121±0.015) protein expression was significantly higher than the control group [(1.54±0.47)%, 0.031±0.011] (tapoptosis rate=10.002, Papoptosis rate=0.001; tCleaved Caspase-3=9.879, PCleaved Caspase-3=0.001). Conclusion Down regulation of Galectin-3 gene expression can inhibit the proliferation of HCCC-9801 cells and induce cell apoptosis by inhibiting the Wnt/β-catenin signaling pathway. Key words: Galectin-3 gene; Cholangiocarcinoma; Proliferation; Apoptosis