Effects of overexpression of CHL1 gene on tumor cell viability，invasive ability and apoptosis of the breast cancer cell and its mechanism

Abstract:

Objective：To investigate the effect and mechanism of overexpression of close homologue of L1（CHL1） gene on tumor cell viability，invasive ability and apoptosis of the breast cancer cell. Methods：The cell experiments were divided into normal group（cells were routinely cultured without external intervention），control group（cells were transfected with pcDNA3.1-CHL1-mimic-NC，conventional culture），and experimental group（cells were transfected with pcDNA3.1-CHL1-mimic，routine culture）. Flow cytometry was used to detect the apoptosis rate of each group of cells，and Transwell cell was used to detect the cell invasion ability. Western blot was used to detect the expression level of CHL1 and cluster of differentiation antigen 44（CD44） in cells of each group. Results：One-way analysis of variance showed that the differences in the apoptosis rate，the number of invaded cells and the expression levels of CHL1 and CD44 in the normal group，control group and experimental group were statistically significant（F=2 698.000，P=0.000；F=655.973，P=0.000；F=914.107，P=0.000；F=3 653.000，P=0.000）. The results of flow cytometry showed that the apoptosis rate of the experimental group was significantly higher than that of the control group（P=0.000）；the Transwell chamber showed that the number of cell invasion of the experimental group was significantly less than that of the control group（P=0.000）；Western blot detection showed the expression of CHL1 in the cells of the experimental group was significantly higher than that of the normal group and the control group（P=0.000），and the expression of CD44 was significantly lower than that of the normal group and the control group（P=0.000）. Conclusion：Overexpression of CHL1 can inhibit the proliferation and invasion ability of breast cancer cells and promote their apoptosis，which may be related to the specific binding of CD44.