MORC2 promotes cell growth and metastasis in human cholangiocarcinoma and is negatively regulated by miR-186-5p

Microrchidia family CW-type zinc finger 2 (MORC2) is a ubiquitously expressed protein that contributes to chromatin remodeling, DNA repair, and lipogenesis. However, its role in cholangiocarcinoma (CCA) remains largely unknown. The aim of this study was to investigate the expression profile of MORC2 and its potential functions in CCA progression. The results showed that MORC2 was upregulated in human CCA specimens and cell lines. MORC2 expression was significantly associated with serum CA19-9 levels (P = 0.009), TNM stage (P = 0.003) and lymph node invasion (P = 0.004). Furthermore, high MORC2 expression was associated with poor 5-year survival (P = 0.016). Functional experiments revealed that MORC2 knockdown could suppress CCA cell proliferation, migration, and invasion both in vivo and in vitro. Mechanically, we found that MORC2 promoted CCA cell metastasis through the EMT process and enhanced proliferation via the Akt signaling pathway. Moreover, MORC2 was negatively regulated by miR-186-5p. MiR-186-5p could influence CCA cell proliferation, migration and metastasis by regulating MORC2. Taken together, the findings of this study demonstrated the oncogenic role of MORC2 in CCA tumorigenesis and metastasis, and clarified an underlying regulatory mechanism mediating MORC2 upregulation, which may provide a novel therapeutic target in CCA treatment.