RESUMO
AIM:To study the mRNA expression and methylation status of imprinted gene SLC22A18 in infiltrating ductal carcinomas(IDCs),and the correlation between methylation status and clinical characteristics in IDCs.METHODS:The methylation status at the promoter regions of SLC22A18 gene was examined by methylation-specific polymerase chain reaction(MSP)in the specimens of IDC from 40 patients.The mRNA expression of SLC22A18 gene was detected by real-time reverse quantitative transcriptase polymerase chain reaction(real-time RT-PCR)in 40 specimens of IDC and the cell line MDA-MB-231.The cell line MDA-MB-231 was treated with 5-aza-2'-deoxycytidine(5'-aza-dc)and trichostatin A(TSA),then MSP and rea1-time RT-PCR were used to detect the methylation status and mRNA expression levels of SLC22A18 gene.RESULTS:SLC22A18 mRNA expression in 40 IDC tissues was lower than that in al1 corresponding adjacent non-cancerous tissues(P