High expression of microRNA-155 is associated with the aggressive malignant behavior of gallbladder carcinoma

Abstract

The prognosis of gallbladder cancer (GBC) remains poor despite recent advances in diagnostics and therapeutic strategies. Although the role of microRNAs (miRs) in GBC have not been well documented, miR-155 is known to be associated with inflammation-associated carcinogenesis in various types of cancers. The aim of this study was to investigate the clinical significance of miR-155 expression and the biological functions of miR-155 in GBC. The expression levels of miR-155 in surgically resected GBCs and gallbladders with pancreaticobiliary maljunction (PBM) were assessed by quantitative reverse transcription-polymerase chain reaction. The relationship between the expression levels of miR-155 and clinicopathological features of GBCs was analyzed. Human GBC cell lines were transfected with miR-155 inhibitors or mimics, and the effects on proliferation and invasion were assessed. miR-155 was significantly overexpressed in GBCs when compared with that in gallbladders with PBM (P=0.007) and normal gallbladders (P=0.04). The high expression level of miR-155 in GBCs was significantly associated with the presence of lymph node metastasis (P=0.01) and a poor prognosis (P=0.02). In vitro assays showed that aberrant expression of miR-155 significantly enhanced GBC cell proliferation and invasion. In conclusion, high miR-155 expression correlates with the aggressive behavior of GBCs, and miR-155 may become a prognostic marker and therapeutic target for GBC.

The role of microRNAs in gallbladder cancer

“…Elevated expression of miR-155 has been described in multiple cancers, reflecting tumor staging, progression and treatment outcomes (61)(62)(63)(64). In accordance with expectations, miR-155 acts as a vital oncogene in GBCs, as was reported by Kono et al (43). Although miR-155 was not upregulated in GBCs compared with pancreaticobiliary maljunction, the expression level of miR-155 was significantly higher in GBCs compared with normal gallbladders.…”

“…These exciting results have also been reported in GBC, since the potential association between various miRNAs and GBC was first reported in 2010 (42). Previous studies have established that aberrant expression of miRNAs exerts a significant effect on cancer-related processes by targeting specific genetic alterations, which provide effective biomarkers for diagnosis, therapeutics and prognosis of GBC (43)(44)(45). In this study, we describe miRNAs in GBC, particularly their roles as oncogenes and tumor suppressors, their value in diagnosis and prognosis and their potential in providing novel therapeutic strategies for disease management.…”

Noncoding RNAs in Gallbladder Cancer

“…Six miRNAs with an oncogenic activity in GBC have been reported in recent studies ( Table 1): miRNA-155, miRNA-20a, miRNA182, miRNA-21, miRNA187, and miRNA-122 [17][18][19][20][21]. All of them have been found to be upregulated in neoplastic tissues in comparison to healthy tissues, while miRNA-187 and miRNA-122 have been determined also in blood samples.…”

MicroRNA-125b predicts clinical outcome and suppressed tumor proliferation and migration in human gallbladder cancer

“…[9][10][11] However, only a few miRNAs had been identified as potential prognostic markers or therapeutic targets in GBC. [12][13][14] The full molecular blueprint of miRNAs expression and their clinical implication in GBC is largely unknown.…”