MIR31HG Prompts The Proliferation And Migration Of Thyroid Cancer Cells And Its Mechanism

Objective:Thyroid carcinoma is the most common type of endocrine malignancy,and its incidence has been steadily increasing in many regions of the world.Papillary thyroid carcinoma(PTC)with excellent prognosis is the most common type of thyroid cancer,but aggressive histological variants,local invasion and distant metastasis are still main death causes in PTC patients.Therefore,it is critical to explore the molecular mechanism of thyroid carcinoma and find new therapeutic targets and prognostic biomarkers for advanced PTC.The regulation of Lnc RNA on carcinogenesis and progression of thyroid carcinoma has attracted extensive attention.Currently,Lnc RNA MIR31 HG plays a significant role in various cancers,but little is known regarding its role in thyroid carcinoma.Therefore,this study mainly explores the expression and clinical significance of MIR31 HG and investigates its function and potential mechanism in PTC.Methods:(1)The expression of MIR31 HG was acquired by online TCGA and GEO database.Additionally,the application of quantitative PCR validated MIR31 HG expression in collected clinical tissues and thyroid cancer cell lines.(2)The relation between MIR31 HG expression and clinical characteristics was analyzed in the TCGA cohort.(3)Recombinant lentivirus vectors were constructed,which were transfected into BCPAP and WRO cells to down-regulate MIR31 HG expression.The biological role of MIR31 HG in cancer cell proliferation was determined by Ed U,CCK-8 and colony formation assays.Transwell and wound healing assays were applied to evaluate the effect of MIR31 HG on invasion and migration of thyroid cancer cells.(4)GO,KEGG and GSEA analysis were completed to explore relative biological process and pathways.Western blotting was used to determine the level of p-ERK1/2.Results:(1)Using TCGA and GEO data sets,the results showed MIR31 HG was significantly upregulated in thyroid cancer compared with normal thyroid tissues(P<0.05);Further,the results of RT-q PCR validated that MIR31 HG level was highly expressed in the collected PTC samples compared with matched normal tissues(FC=5.71,P<0.01);Additionally,MIR31 HG expression was significantly upregulated in several cancer cell lines including BCPAP,WRO and K1 cells(P<0.05).(2)In TCGA cohort,MIR31 HG expression was related with lymph node metastasis(P<0.001)and histological variants(P<0.001).(3)The results of Ed U,CCK-8 and colony formation assays indicated that knockdown of MIR31 HG inhibited proliferation of BCPAP and WRO cells.The results of transwell and wound healing assays implied that knockdown of MIR31 HG inhibited migration and invasion of BCPAP and WRO cells.(4)The results of Go,KEGG,and GSEA indicated that MIR31 HG was related with MAPK pathways and its downregulation also reduced the levels of phosphorylated ERK1/2 in thyroid cancer cells.Conclusion:MIR31HG was significantly increased in PTC.The elevation of MIR31 HG was correlated with lymph node metastasis and its expression was subtype-specific in PTC.MIR31 HG might be involved in thyroid cancer cell proliferation,migration and invasion by regulating MAPK signal pathway.These founding provided new ideas for illustrating molecular mechanism of thyroid carcinoma and exploring effective therapeutic targets and prognostic biomarkers.Figure 16,table 15,references 53...