Study On The Mechanism Of TET1 Repression In Renal Cell Carcinoma

Renal cell carcinoma,referred to as kidney cancer,is one of the most common malignant tumors in the urinary system.DNA aberrant methylation plays an important role in the development of RCC.Ten-eleven translocation 1(TET1)could regulate the methylation level of the genome as a member of the DNA demethylase family,and its dysregulation in RCC may be associated with RCC progression.And there is no report on the mechanism by which TET1 is down-regulated in RCC.Therefore,this study aimed to investigate the mechanism of TET1 dysregulation in RCC and its effect on RCC cells invasion and migration1.Detect the expression level of TET1 in RCCThe expression of TET1 in RCC and its adjacent tissues was detected by RT-qPCR and Western Blot,and the 5hmC level was detected by Dot Blot.The results showed that TET1 expression was significantly decreased at the transcriptional level and protein level compared with the matched paracancerous tissues,and 5hmC was also significantly decreased in RCC.And down-regulation of TET1 promoted RCC cells invasion and migration evaluated by transwell and scratch test2.Investigation of mechanism underlying the expression of TET1 decreased in RCCBy aligning the microRNA with the TargetScan database,and experiment with the luciferase reporter gene method,it was found that miR-183 can inhibit luciferase activity by binding to TET1 3’-UTR and inhibit the expression of TET1 in 786-O and 769-P cells.And transwell assay indicated that up-regulation of miR-183 promoted cell invasion and migrationIn addition,fumarate dehydrogenase(FH)was down-regulated in RCC tissues compared with the matched paracancerous tissues by RT-qPCR and Western Blot detection,and down-expression of FH could inhibit the activity and expression of TET1 by accumulating intracellular fumarate3.Explore the mechanism that down-expression of TET1 promoted RCC cells invasion and migration.We found the expression of miR-200c decreased after TET1 knockdown by RT-qPCR analysis.Through transwell and scratch tests,we found that down-regulation of miR-200c promoted RCC cells invasion and migration.The DNMTs inhibitor decitabine could up-regulate miR-200c,and then the expression of E-cadherin was increasead,which inhibiting the invasion and migration ability of 786-O and 769-P cells.In conclusion,the expression of TET1 was significantly decreasead in RCC,consistent with the reports.Our study has found that miR-183 and FH mediated the inhibition of TET1 expression in RCC,providing an experimental basis for elucidating the regulatory network of TET1 expression in RCC.