Effect of silencing transcription factor 21 gene by siRNA on Kiss-1 gene expression in human colorectal cancer HT-29 cells

Abstract

Objective To investigate the effect of silencing transcription factor 21 (TCF21) gene expression by small interfering RNA (siRNA) on the expression of Kiss-1 gene and the cell biological behaviors of proliferation,invasion and migration in human colorectal cancer cell line HT-29 in vivo.Methods A specific siRNA molecule fragment for TCF21 was designed,and transfected into HT-29 cells by lipofectamineTM 2000.The experimental group,negative control group and blank control group were set up.Real-time reverse transcriptase-polymerase chain reaction (RT-qPCR) was used to detect the expression levels of TCF21 and Kiss-1 mRNA at 48 h after transfection.By using Western blotting,the expression levels of TCF21 and Kiss-1 proteins at 72nd h after transfection was examined.The Cell Counting Kit-8 (CCK-8) was used to detect cell proliferation capacity,and Transwell assay to detect the invasion and migration capacity at 72nd h post-transfection.Results The siRNA fragment could silence TCF21 gene expression successfully,then leading to a substantial drop-off in the expression of Kiss-1 mRNA (0.58 ± 0.02) and protein (0.3491 ±0.0009,P ＜0.05).CCK-8 test and Transwell assay revealed that cells after transfection proliferated more rapidly than before transfection and had an increasing capability of invasion and migration (P ＜ 0.01).Conclusion The silencing of TCF21 expression in colorectal cancer cell line HT-29 cells could decline the expression level of Kiss-1 mRNA and protein,and lead to the corresponding changes of cell biological behaviors,suggesting TCF21 gene might be the upstream regulator of Kiss-1 gene. Key words: Colorectal cancer; Small interfering RNA; Transcription factor 21; Kiss-1 ; Biological behavior