HCMV-encoded miR-UL112-3p promotes glioblastoma progression via tumour suppressor candidate 3.

Glioblastoma (GBM) is the most prevalent and lethal type of primary malignant brain tumour. Recent studies suggest that the discovery of human cytomegalovirus (HCMV)-encoded microRNAs (miRNAs) might play a role in the pathogenesis of diseases, including GBM. In this study, we aimed to analyse the expression and function of HCMV-encoded miRNAs in GBM. We found that miR-UL112-3p expression was significantly elevated in GBM, and its expression levels were highly associated with glioma size, differentiation, WHO stage and the overall and disease-free survival of patients. The overexpression of miR-UL112-3p in the GBM cells promoted cell proliferation, clone formation, migration and invasion. In contrast, the down-regulation of miR-UL112-3p exerted an inverse effects. Tumour suppressor candidate 3 (TUSC3), a potential target gene of miR-UL112-3p, was inversely correlated with miR-UL112-3p expression in GBM tissues and cell lines. Furthermore, we demonstrated that TUSC3 was directly regulated by miR-UL112-3p, and the ectopic expression of TUSC3 reversed the effects of miR-UL112-3p on GBM progression via the AKT signalling pathway. Taken together, these findings collectively demonstrate that miR-UL112-3p exerts its oncogene function by directly targeting TUSC3 in GBM, indicating a potential novel therapeutic target for GBM.