Restoration of expression of transforming growth factor-beta type II receptor in murine renal cell carcinoma (renca) cells by 5-Aza-2'-deoxycytidine.
The murine renal cell carcinoma (Renca) cells are insensitive to TGF-beta due to a lack of TGF-beta type II receptor (TbetaR-II). The objective of the present study is to determine the mechanism of this loss of sensitivity to TGF-beta in Renca cells. Renca cells were cultured and treated with 5-Aza-2'-Deoxycytidine (5-Aza), a specific inhibitor of methylation. Expression of TGF-beta type I receptor (TbetaRI) and TbetaRII was determined by RT-PCR and Western blot analysis before and after the treatment of Renca cells with 5-Aza. The expression of phosphorylated Smad2 (P-Smad2) was determined by Western blot analysis. TGF-beta levels in the conditioned medium were measured by ELISA. Renca cells did not express TbetaR-II prior to 5-Aza treatment. After 5-Aza treatment, these cells expressed TbetaR-II at both mRNA and protein levels, which corresponded to the restoration of sensitivity to TGF-beta by an increase in P-Smad2. Levels of TGF-beta1 were similar before and after 5-Aza treatment. Results of the present study indicated that, in Renca cells, the loss of sensitivity to TGF-beta is likely due to a promoter hypermethylation in the TbetaR-II gene.
Zhang
Qiang
Q
Department of Urology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Avenue. Tarry 16-733, Chicago, IL, 60611, USA.
Rubenstein
Jonathan N
JN
Liu
Victoria C
VC
Park
Irwin
I
Jang
Thomas
T
Lee
Chung
C
D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D001374:Azacitidine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002292:Carcinoma, Renal Cell / Q000188:drug therapy / Q000378:metabolism*; D045744:Cell Line, Tumor; D019175:DNA Methylation; D000077209:Decitabine; D007680:Kidney Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D051379:Mice; D011401:Promoter Regions, Genetic; D017346:Protein Serine-Threonine Kinases; D012333:RNA, Messenger / Q000032:analysis; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000032:analysis / Q000235:genetics*; D016212:Transforming Growth Factor beta / Q000502:physiology; D053773:Transforming Growth Factor beta1
D000964:Antimetabolites, Antineoplastic; D012333:RNA, Messenger; D018125:Receptors, Transforming Growth Factor beta; C508961:Tgfb1 protein, mouse; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D000077209:Decitabine; D017346:Protein Serine-Threonine Kinases; D000077294:Receptor, Transforming Growth Factor-beta Type II; D001374:Azacitidine