Objective: Previous studies have shown that microRNA-765 (miR-765) is involved in certain biological behaviors of human cancers. However, abnormal expression and function of miR-765 have not been reported in osteosarcoma (OS).
Patients and methods: Changes in the expression of miR-765 and MTUS1 (Microtubule-associated tumor suppressor 1) were examined via Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis. The function of miR-765 was investigated through Cell Counting Kit-8 (CCK-8) and transwell assays in OS. The target of miR-765 was identified using a Dual-Luciferase reporter assay.
Results: MiR-765 was upregulated in OS tissues. And upregulation of miR-765 promoted cell proliferation, migration and invasion in OS. In addition, MTUS1 was confirmed as a direct target gene of miR-765. Moreover, miR-765 promoted the progression of OS through targeting MTUS1. Furthermore, miR-765 was involved in tumorigenesis of OS through activating extracellular-signal-regulated kinase/ epithelial-mesenchymal transition (ERK/EMT) pathway.
Conclusions: MiR-765 targets MTUS1 to promote the progression of OS via mediating the ERK/EMT pathway. Therefore, miR-765 may be used as a novel biomarker for the diagnosis of OS.