The Study Of MicroRNA-375 Targeting MTDH Regulates The Proliferation Of Human Oral Squamous Cell Carcinoma Cells

Objective:To detect the expression of mi R-375 and MTDH in human oral squamous cell carcinoma(OSCC)tissues and cell lines,analyze the relationship between the expression level of mi R-375 and poor prognostic factors of OSCC,and explore the effect of mi R-375 targeting MTDH on the proliferation of OSCC cells,so as to provide new ideas for the early diagnosis,personalized treatment and prognosis of OSCC.Methods:(1)Real-time quantitative PCR(q PCR)was used to detect the expression of mi R-375 in human oral squamous cell carcinoma cell lines Cal-27,Fadu and normal oral mucosa cell line HOEC.(2)Real-time quantitative PCR was used to detect the expression of mi R-375 in oral squamous cell carcinoma tissues and adjacent tissues,and analyzed the correlation between the expression level and the prognosis of patients.(3)Bioinformatics was used to predict the target gene of mi R-375,MTDH was selected as the target gene for the experiment.The m RNA and protein expression of MTDH gene were detected by q PCR and Western Blot respectively.(4)Double luciferase assay was used to verify that MTDH is the target gene of mi R-375.Mi R-375 mimic and inhibitor were transfected into OSCC cell line Cal-27,the expression of mi R-375 and MTDH was detected by q PCR and Western Blot,the changes of cell proliferation ability after transfection were detected by CCK-8 assay.The experimental results were statistically treated,and P<0.05 indicated statistically significant differences.Results:(1)The expression of mi R-375 in oral squamous cell lines Cal-27 and Fadu was significantly lower than that in HOEC(P<0.05).(2)The expression levels of mi R-375 in OSCC tissues were significantly lower than those in adjacent tissues(P<0.05),and the low expression of mi R-375 was associated with poor prognosis factors,such as clinical stage,pathological grade and regional lymph node metastasis in OSCC patients(P<0.05).(3)The m RNA and protein expression of MTDH gene in OSCC tissues and cell lines were higher than those in adjacent tissues and oral mucosal normal epithelial cell lines(P<0.05),the expression level of mi R-375 and MTDH gene were negatively correlated in OSCC.(4)The results of dual luciferase assay showed that MTDH was the target gene of mi R-375,after mi R-375 mimic was transfected into Cal-27 cell line,the proliferation ability of the cells was significantly inhibited(P<0.05).Conclusion:(1)In OSCC tissues: Compared with adjacent tissues,the expression level of mi R-375 was significantly downregulated and the expression level of MTDH was significantly upregulated.(2)The low expression of mi R-375 might predict the poor prognosis of OSCC,suggesting that the measurement of mi R-375 in tissues is potentially valuable in predicting the prognosis of OSCC.(3)MTDH is the target gene of mi R-375,overexpression of mi R-375 can inhibit the proliferation of oral squamous cell carcinoma cell Cal-27,which indicates that mi R-375 plays a role of tumor suppressor gene in the progress of OSCC,suggesting that mi R-375-MTDH may be a target for the treatment of OSCC.