MicroRNA-155 expression as a prognostic factor in patients with gallbladder carcinoma after surgical resection.

Background: MicroRNA-155 (miR-155) is over-expressed in both hematopoietic malignancies and solid tumors. In the present study, we investigated the clinical significance of miR-155 in gallbladder carcinoma among Chinese population.

Methods: Tissue specimens were collected from 133 patients who had undergone surgical resection at Shandong Provincial Hospital, Shandong University between May 2008 and April 2014. We profiled miR- 155 expression in the gallbladder carcinoma tissues and normal gallbladder tissues by qRT-PCR. The Kaplan-Meier method was used to analyze the 5-year survival rate.

Results: The expression levels of miR-155 were significantly higher in gallbladder carcinoma tissues than that in normal gallbladder tissues (P<0.001). High miR-155 expression was significantly associated with TNM stage (P=0.003), lymph node status (P=0.042), liver metastasis (P=0.010), and differentiated degree (P<0.001). We found that gallbladder carcinoma patients with high miR-155 expression level had distinctly shorter overall survival than patients with low miR-155 expression level (P=0.03). Multivariate analysis revealed that miR-155 expression level was independent prognostic factors for overall survival (HR=2.394, 95% CI: 1.568-10.034; P=0.009).

Conclusion: High miR-155 expression is a prognostic indicator for poor prognosis of patients with gallbladder carcinoma among Chinese population.