Effect of CHL1 gene on cell viability, invasiveness and apoptosis in neuroblastoma cells

Abstract

Objective: To investigate the effect and mechanisms of CHL1 gene overexpression on cell viability, invasiveness and apoptosis in neuroblastoma cells. Methods: The empty plasmid (pcDNA3.1 group) and CHL1 recombinant plasmid (pcDNA3.1-CHL1 group) were transfected into SK-N-SH human neuroblastoma cells, and the untransfected cells were used as blank control. Forty-eight hours after transfection, the protein expressions of CHL1, PCNA, MMP-2, Bax, STAT3 and p-STAT3 were detected by western blot. Meanwhile, cell viability, invasion and apoptosis were detected by MTT, transwell and flow cytometry assays, respectively. Results: The expression level of CHL1 protein in pcDNA3.1-CHL1 group was 0.612±0.052, which was higher than that of pcDNA3.1 group 0.122±0.014 and blank control group 0.120±0.013, with statistically significant difference (P<0.05). After 24, 48 and 72 hours of transfection, the absorbance (A) values of SK-N-SH cells in the pcDNA3.1-CHL1 group were 0.328±0.035, 0.502±0.051 and 0.688±0.064, respectively, whereas those in the pcDNA3.1 group were 0.562±0.050, 0.796±0.065 and 0.973±0.077, respectively. The differences were statistically significant (P<0.05). The invaded cells in the pcDNA3.1-CHL1 group were 104.9±3.7, which were lower than that in the pcDNA3.1 group (175.6±4.6), with statistically significant difference (P<0.05). Additionally, the apoptotic rate of pcDNA3.1-CHL1 cells was (23.46±1.22)%, which was higher than that in pcDNA3.1 group (3.45±0.20)%(P<0.05). Furthermore, the levels of PCNA, MMP-2, Bax and p-STAT3 proteins in pcDNA3.1-CHL1 group were 0.156±0.018, 0.122±0.015, 0.285±0.032 and 0.023±0.004, respectively, whereas those in pcDNA3.1 group were 0.542±0.053, 0.196±0.021, 0.073±0.009 and 0.057±0.007, respectively. There were statistically significant differences between two groups (P<0.05). Conclusion: Overexpression of CHL1 inhibits the cell viability and invasion, as well as induces apoptosis of neuroblastoma cells, which is related to the inhibition of STAT3 signaling pathway.