MicroRNA-93 promotes the tumorigenesis of osteosarcoma by targeting TIMP2.

Hua Zhang,Fanrui Meng,Yunliang Guo,Hongyu Yan,Shandi Zhang,Jidong Zhang,Hanzhong Zhu

doi:10.1042/bsr20191237

Abstract

Osteosarcoma (OS) is the most frequent primary bone malignancy and affects adolescents and young adults. Recently dysregulation of miRNAs has received more attention because of its extensive role in OS carcinogenesis. This research was designed to verify how microRNA-93 (miR-93) and tissue inhibitor of matrix metalloproteinase 2 (TIMP2) be involved in OS development. At first, the levels of miR-93 and its predictive target gene TIMP2 were detected in OS and osteoblast cell lines, and 62 pairs OS and adjacent non-OS specimens by real-time PCR and western blot. Then, viability, invasion, and epithelial mesenchymal transition (EMT) of OS cell lines were examined when overexpressed or knocked down miR-93, or overexpressed TIMP2. Finally, the interaction between miR-93 and TIMP2 was evaluated using mutation, gain, and loss experiment. Our data indicated that miR-93 was increased while TIMP2 was decreased in both OS cell lines and tissues. MiR-93 high-expression and TIMP2 low-expression were related with poor overall survival and prognosis of OS patients. Overexpression or knockdown experiment indicated that miR-93 enhanced OS cell viability, invasion, and EMT expression. TIMP2 could inhibit OS cell viability, invasion, and EMT expression. Further, miR-93 directly targeted TIMP2 and negatively regulated TIMP2 level in OS cells. And up-regulation of TIMP2 reversed the effects of miR-93 in OS. Finally, miR-93 regulated the oncogenic functions in OS cells by regulating the expression of TIMP2. In conclusion, our study demonstrates that miR-93 may exert an oncogenic function while TIMP2 may act as a tumor suppressor on OS.

Highlights

Human osteosarcoma (OS) is the most frequent primary bone malignancy and affects adolescents and young adults especially those aged from 15 to 19, and is characterized by occurring at the extremities of long bones and originating from primitive osteogenic mesenchymal cells [1]
We demonstrated for the first time that up-regulation of miR-93 and decreasing of tissue inhibitor of matrix metalloproteinase 2 (TIMP2) are strongly positively correlated with poor prognosis
We detected the TIMP2 mRNA level in OS cell lines, it showed that TIMP2 mRNA level was lower in OS cells compare to the normal hFOB cells (Figure 1B)

Summary

Introduction

Human osteosarcoma (OS) is the most frequent primary bone malignancy and affects adolescents and young adults especially those aged from 15 to 19, and is characterized by occurring at the extremities of long bones and originating from primitive osteogenic mesenchymal cells [1]. Chemotherapeutic treatments combined with surgical methods have extensively applied in treatment of OS [2,3]. Despite considerable progress in the diagnosis and treatment of OS, the metastasis rates and mortality of OS are still very high [4], and the clinical effect of OS treatment remains unsatisfactory [5,6]. It is important to elucidate study on the molecular mechanism of osteosarcoma. Many studies have confirmed that dysregulated miRNAs were contributed to multiple physiological processes in different malignancies (including osteosarcoma), such as apoptosis, proliferation, and autophagy [8–10]. Previous evidence has suggested that miR-93 was abnormally increased in OS patients’ tissues [11]. The specific mechanism of miR-93 in osteosarcoma is still obscure. Thence determining the exact molecular mechanisms of miR-93 in OS carcinogenesis might contribute to improving diagnose and prognosis of patients with this tumor

Methods

Results

Discussion

Conclusion