title: [Microsatellite instability in renal cell carcinoma and its mechanisms].
abstract: OBJECTIVE
  To study the expression of microsatellite instability (MSI) in renal cell carcinoma (RCC) and its relationship with gene mutation.
  
  
  METHODS
  Tumor samples from 34 patients with RCC were analyzed for MSI by PCR. RT-PCR was used to evaluate the expression of mRNA of 5 human mismatch repair (MMR) genes in RCC and RCC cell lines. Mutation of hMLH1 gene coding regions was detected by PCR-SSCP. PCR was used to check the mutations of TGF-beta R II gene and BAX gene in 15 MSI-positive samples of RCC.
  
  
  RESULTS
  Microsatellite changes were detected in 15 of 34 patients with RCC (44.1%). It might be associated with the progression of this disease. There were 3 of 15 MSI-positive RCC cases without expression of MMR gene hMLH1, and in 3 of 15 cases its expression was decreased. All 5 MMR genes were expressed in normal and RCC 949 cell line. There were three mutations in 15 MSI-positive cases. Frame shift mutation of TGF beta R II gene and BAX gene was found in 6 and 4 of the 15 cases with MSI, respectively, but it was not found in MSI-negative RCC and normal tissue.
  
  
  CONCLUSIONS
  MSI and expression of MMR genes are associated events in RCC. The effect of gene mutation on tumorgenerasis may be related to MSI.
authors.affiliation: Department of Urology, First Hospital, Institute of Urology, Beijing Medical University, Beijing 100034, China.
authors.forename: L
authors.initials: L
authors.lastname: Yu
authors.forename: D
authors.initials: D
authors.lastname: Tang
authors.forename: Y
authors.initials: Y
authors.lastname: Ding
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020137:Base Pair Mismatch; D002292:Carcinoma, Renal Cell / Q000235:genetics*; D002352:Carrier Proteins; D018450:Disease Progression; D005260:Female; D016368:Frameshift Mutation; D006801:Humans; D007680:Kidney Neoplasms / Q000235:genetics*; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics*; D008875:Middle Aged; D000070957:MutL Protein Homolog 1; D009154:Mutation; D009363:Neoplasm Proteins / Q000172:deficiency / Q000235:genetics; D009687:Nuclear Proteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured; D051028:bcl-2-Associated X Protein
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C494826:BAX protein, human; D002352:Carrier Proteins; C501486:MLH1 protein, human; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D018125:Receptors, Transforming Growth Factor beta; D051028:bcl-2-Associated X Protein; D017346:Protein Serine-Threonine Kinases; D000077294:Receptor, Transforming Growth Factor-beta Type II; D000070957:MutL Protein Homolog 1