ABSTRACT
Objective: To investigate the inhibitory effect of nitidine chloride (NC) on human esophageal carcinoma cell line Eca109 and the molecular mechanism of its induction. Methods: CCK-8 method was used to detect the inhibition rate of human esophageal cancer Eca109 cells with different concentrations of NC and different intervention time. According to the result of CCK-8 method, the experiment was divided into four groups, and the concentrations of NC in each group were 0, 5, 10, and 15 μmol/L, respectively, and the drug action time was 48 h. The apoptotic rate was detected by flow cytometry with Annexin V-FITC/PI double staining. The mRNA expressions of Caspase-3, Caspase-9, and Noxa were detected by qRT-PCR. The expressions of cleaved Caspase-3 and Bcl-2, p53, and Noxa protein levels were detected by Western blotting. Results: NC had inhibitory effect on Eca109 cells in a certain range of time and dose-dependent manner. Flow cytometry showed that NC at 5 μmol/L mainly induced early apoptosis (P < 0.01); NCs at 10 and 15 μmol/L mainly induced late apoptosis (P < 0.01). qRT-PCR results showed that the mRNA expression of Caspase-3, Caspase-9 and Noxa was increased with the increase of NC concentration, of which 10 and 15 μmol/L group increased significantly. The results of Western blotting showed that the protein levels of cleaved Caspase-3, p53, and Noxa were both increased with the increase of NC concentration (P < 0.01), but the increase of Noxa was not significant in 5 μmol/L group (P < 0.01). The expression of Bcl-2 protein was decreased with the increase of NC concentration, and which was significantly higher in 10 and 15 μmol/L groups (P < 0.05, P < 0.01). Conclusion: The inhibitory effect of NC on human esophageal carcinoma Eca109 cells is mainly through apoptosis. The apoptosis of NC induced of Eca109 cells is associated with increased expression of p53 and Noxa, downregulation of Bcl-2, and activation of Caspase-3.