study of mir-143 replacement effect on growth and migration inhibition in oral squamous cell carcinoma cell lin (HN-5)

Abstract

Background. Oral squamous cell cancer (OSCC) is one of the causes of death worldwide and its treatment is a global challenge. The microRNAs are small (~18–22 nucleotides) non coding RNAs that an important regulator gene expression. The aim of this study is to determine the transfection effects of microRNA-143 mimic in HN-5 cancer cells and explore molecular mechanisms responsible for the anticancer processes. Methods. In this study, firstly expression levels of microRNA-143, K-Ras, MMP9 and C-Myc were measured by the qRT-PCR method in OSCC tissues. Then, microRNA-143 mimic was transfected into HN-5 cells via JetPEI transfection reagent and the cytotoxic effects of microRNA-143 mimic on HN-5 cells were evaluated. To evaluate the effects of microRNA-143 mimic on the inhibition of cell migration, wound healing assay was performed. Finally, the expression levels of microRNA-143, K-Ras, MMP9 and C-Myc were measured by the qRT-PCR method in HN-5 cells .The results from experiments were analyzed by using GraphPad Prism version 6 program. All values are indicated as means ± standard deviation (SD) and all analyses have been repeated at three times. Student's t-test and ANOVA were used to determine the statistical significance of differences between groups. Results. According to the obtained data, the started metastatic pathway was due to the down-regulation of microRNA-143, mainly, in the late-stage oral cancer. In the following, results of wound healing assays showed that microRNA-143 mimic inhibited cell migration in HN-5 cell line compared with control groups. Finally, data of gene expression showed that microRNA-143 mimic reduced K-Ras, MMP9 and C-Myc gene expression compared to control cells. Conclusion. According to this study, the activation metastatic pathways were due to the down regulation of microRNA-143. According to this, microRNA-143 can inhibit cells migration in vitro through down-regulating the expression of metastasis-related genes. Hence, microRNA-143 can be a new diagnostic biomarker and new therapeutic target for OSCC.