Screening And Verification Of Related MiRNA Of Esophageal Cancer Radiosensitivity

Background and objective：The main treatment for esophageal cancer includethe surgical treatment,radiation therapy and chemotherapy.But because the earlysymptoms of occult,when they were treated, the most of esophageal cancerpatients already belong to advanced, so losing the chance of operation, theradiation therapy became one of the main and effective treatment foresophageal cancer.There are differences in radiosensitivity of esophageal cancerindividuals,which led to a difference in the efficacy of radiotherapy, sopredicting the radiosensitivity of esophageal cancer has important significance.Studies have shown that esophageal cancer cells of the different radiosensitivitywith differences in miRNA expression profiles Whether or not esophagealcarcinoma of the different radiosensitivity has also differentially expressingmiRNA, mechanisms and how.Studies have shown that high expression ofBmi-1is closely associated with the radioresistance of esophagealcancer.Bioinformatics software analysis shows Bmi-1is one of the target genesof miR-203. The aim of experiment have two：A is to study esophagealcancer patients of the different radiosensitivity have different miRNAexpression, B is to whether or not through down-regulation the expression ofBmi-1,miR-203can enhance radiosensitivity of TE-1cells.Methods:1.According to RECIST guidelines (version1.1) standard will,six cases of esophageal squamous cell carcinoma patients by concurrentchemoradiotherapy were divided into insensitive and sensitive group, and tissuesamples were collected before treatment.MiRNA microarray was used toanalyzed six cases of esophageal squamous cell carcinoma patients biopsyspecimens and predict their target genes.The miR-374c-5p was transfected tooesophageal cancer cell lines TE-1.RT-PCR was used to detect the expressionof target genes CD47, CYFIP2.2.Combining the results of the chip with the literature, miR-203and Bmi-1were selected to do further experiments.The miR-203mimics and negativecontrol transfection sequence were transfected into TE-1cells with Lipo2000liposome.The experiment was divided into three groups：miR-203mimics-transfected group, negative control-transfected group， and blankcontrol group.Western blot assay was conducted to detect Bmi-1expresionalternation. Clonogenic assay was used to measure the mitotic cell death.Results:1.Compared with the not sensitive group, two miRNAs（miR-1272，miR-5571-5p）were up-regulated more than1.5times;eight miRNAs（miR-125b-1-3p，miR-3680-5p， miR-5002-3p， miR-374c-5p，miR-3908，miR-4292， miR-1915-3p， miR-4516）were down-regulated more than1.5times,in the radiation-sensitive group. Studies have shown that miR-125b-1-3pis closely related to cancer development and chemoradiation sensitivity,2.CYFIP2, DDIT4, CD47,PTTG1, TNFRSF25and cyclinE2are miR-374c-5predicted target genes. These target genes are closely related to tumor apoptosis occurs, the development and prognosis,3.Compared with the negative control group, the expression of CD47andCYFIP2did not significantly reduced in the transfection group,4.Western blot results showed compared with the negative control and blankcontrol group,Bmi-1was significantly lower in the transfecting group,and thedifference was statistically significant (P <0.05);comparing negative controlgroup with blank group,Bmi-1was lower,but the difference was notstatistically significant (P>0.05)5.Clonogenic assay showed the overexpression of miR-203could enhance theradiosensitivity of TE-1cells. In the Experimental group, negative controlgroup,and blank control group D0were1.498,1.6295,1.7, and Dq were1.3335,1.8578,1.9715.In the three group SF2were0.6065,0.73668,0.74595, andα/βwere3.8165,1.0270,1.1409. In the experimental group D0, Dq, SF2weredecreased, and α/β was increased. The differences were statistically significant.Conclusion:1.10differentially expressing miRNA may be related to theradiosensitivity of esophageal squamous cell carcinoma in this study, whichmiR-125b-1-3p is closely related to cancer development and chemoradiationsensitivity. CD47, CYFIP2, DDIT4and PTTG1are target genes ofmiR-374c-5p, and there target genes are closely related to tumor.2.Through down-regulation Bmi-1,miR-203can enhance radiosensitivity ofTE-1cells.