MPZL1 is highly expressed in advanced gallbladder carcinoma and promotes the aggressive behavior of human gallbladder carcinoma GBC-SD cells

Myelin protein 0-like 1 (MPZL1) has been reported to have a role in hepatocellular carcinoma. However, to the best of our knowledge, there have been no studies on the function and molecular mechanism of MPZL1 gene in gallbladder carcinoma. The present study confirmed that MPZL1 was upregulated in four gallbladder carcinoma tissues according to the mRNA microarray analysis. The results of the immunohistochemical analysis of tissues from 82 patients with gallbladder carcinoma demonstrated that patients with advanced tumor stages (both T and N stage) had higher positive expression of MPZL1. Moreover, a total of 20 cases of gallbladder carcinoma and matched paired paracarcinoma tissues along with 20 samples of healthy gallbladder tissue from patients with cholecystitis were analyzed using reverse transcription-quantitative PCR and western blotting. The results demonstrated that the expression of MPZL1 in gallbladder carcinoma tissues was significantly higher than that of paired paracarcinoma tissues and randomly matched normal gallbladder epithelial tissues. According to the Tumor-Node-Metastasis classification, the expression level of MPZL1 protein in stage IV gallbladder carcinoma was significantly higher than that in stage III gallbladder carcinoma. The enhanced expression of MPZL1 gene appeared to improve the migration ability of GBC-SD cells. Conversely, GBC-SD cells that transfected with MPZL1 siRNA exhibited decreased migration ability. The results of proliferation experiments showed that the knockdown of MPZL1 siRNA caused impairments in GBC-SD cell proliferation. On the contrary, the overexpression of MPZL1 increased the proliferation ability of GBC-SD cells. The results of flow cytometry analyses indicated that the upregulation of MPZL1 had an anti-apoptotic effect on GBC-SD cells. In conclusion, the present study showed that the expression and protein levels of MPZL1 were significantly higher in gallbladder carcinoma tissues, especially in patients diagnosed with advanced tumor stages. Overexpression of MPZL1 may have promoted the invasion, metastasis, proliferation and survival of GBC-SD cells.