Methylation and aberrant expression of Wnt antagonist SFRP1 in bladder cancer

Objective To measure the expression of SFRP1 in bladder cancer and explore the corresponding mechanism,in order to study the roles of SFRP1 in the pathogenesis of bladder cancer.Methods SFRP1 mRNA was detected by RT-PCR.Methylation status of SFRP1 was detected by methylation specific PCR.SFRP1 protein was determined by Western blotting.Results SFRP1 was methylated in bladder cancer cell lines T24 and 5637,not in SCaBER.SFRP1 mRNA and protein were detected in SCaBER,but not in T24 and 5637.Six hours after treating T24 and 5637 with 5'-aza-deoxycytidine,both T24 and 5637 expressed SFRP1 mRNA and protein.In 45 bladder cancers,methylation of SFRP1 was detected in 28 (62.2％).In matched cancer adjacent tissues,6 (13.3％) were found with SFRP1 methylation.The methylation rate in bladder cancers was significant higher than that in matched cancer adjacent tissues (P ＜ 0.01).Conclusions SFRP1 is downregulated in some bladder cancers due to methylation.SFRP1 methylation and aberrant expression may be involved in the pathogenesis of bladder cancers. Key words: Secreted frizzled-related protein 1; Methylation; Bladder cancer