Wnt拮抗因子SFRP5在胃癌中的甲基化和异常表达

Methylation and Aberrant Expression of Wnt Antagonist SFRP5 In Gastric Cancer

目的检测Wnt拮抗因子分泌型Frizzled相关蛋白(SFRP5)在胃癌中的甲基化和表达状态,探讨SFRP5在胃癌发病机制中的作用。方法采用甲基化特异性PCR(MSP)检测SFRP5在胃癌中的甲基化状态,采用逆转录PCR(RT-PCR)和即时定量PCR(real-time PCR)检测SFRP5在胃癌中的表达状态。结果在胃癌组织中,有29例(72.5%)检出SFRP5甲基化,在其相应的癌旁组织中,有4例(10%)检出SFRP5甲基化。SFRP5在胃癌组织中的甲基化频率显著高于癌旁正常组织(χ2=32.237,P<0.001)。SFRP5mRNA在胃癌组织中表达显著低于癌旁正常组织(P<0.001)。SFRP5在胃癌细胞系HGC-27、AGS和NCI-N87中发生甲基化,表达消失,而在SGC-7901中未发生甲基化,存在表达。结论SFRP5甲基化及异常表达在胃癌中是一种较为普遍的现象,其参与了部分胃癌的发病过程。

Objective To detecte the methylation and the expression of Wnt antagonist Secreted Frizzled-related Protein 5 （SFRPS） in gastric cancer and to explore the role of SFRP5 in gastric careinogenesis. Methods Methylation status of SFRP5 was detected by Methyla- tion-specific PCR （MSP）. Expression of SFRP5 was determined by Reverse-transcription PCR （RT-PCR） and Real-time PCR. Results SFRP5 methylation was found in 29 （72.5%） gastric cancers and in 4 （10%） matched cancer adjacent normal tissues. The frequency of methylation for SFRP5 was significantly higher in gastric cancers than that in matched normal tissues （Xz=32.237,P 〈 0.001）. Level of SFRP5 expression in gastric cancers was significantly lower than that in matched normal tissues （P 〈 0.001 ）. SFRP5 was methylated and not expressed in gastric cell line HGC-27,AGS and NCI-N87. And SFRP5 was expressed and not methylated in gastric cell line SGC-7901. Conclusion Methylation and aberrant expression of SFRP5 are common in gastric cancer and play a role in gastric carcinogenesis.