HOXC12基因甲基化是胰腺癌的潜在诊断和预后标志物

Methylation of HOXC12 is a potential diagnostic and prognostic marker of pancreatic cancer

目的在胰腺癌中探讨HOXC12基因的启动子区甲基化状态及其作为诊断和预后标志物的可能性。方法应用半定量RT-PCR和甲基化特异性PCR(methylation-specific PCR,MSP)技术检测10株胰腺癌细胞系中HOXC12的表达及启动子区甲基化情况,应用MSP在145例胰腺癌组织中检测HOXC12启动子区甲基化情况,并分析HOXC12甲基化与临床病理因素之间的关系。结果HOXC12在SW1990、Panc10.05、AsPC1、MIAPaCa2、PANC1、PATU8988T、Capan1、PANC-28和JF305细胞中缺失表达,其MSP结果为完全甲基化状态,在Panc5.04中表达水平明显降低,MSP结果呈部分甲基化状态。应用5-aza-dc处理细胞后,HOXC12在SW1990、Panc10.05、AsPC1、MIAPaCa2、PANC1、PATU8988T、Capan1、PANC-28和JF305细胞恢复表达,在Panc5.04细胞中表达增加。表明HOXC12基因在胰腺癌中的表达受甲基化调控。在145例原发性胰腺癌组织中,50.34%(73/145)病例发生HOXC12甲基化,甲基化与年龄、性别、饮酒及神经侵犯相关(P均<0.05),与患者的肿瘤大小、淋巴结转移、分化程度等因素无关(P均>0.05)。结论HOXC12基因在胰腺癌组织中频繁发生甲基化,其表达受启动子区甲基化调控,HOXC12甲基化是胰腺癌潜在的诊断和预后标志物。

Objective To investigate the methylation status of HOXC12 gene in human pancreatic cancer and its potential application in the diagnosis and prognosis.Methods Semi-quantitative RT-PCR and methylation-specific PCR(MSP)were used to detect HOXC12 expression and promoter region methylation in 10 pancreatic cancer cell lines and 145 cases of primary pancreatic cancer samples.Chi-square test was used to analyze the association of HOXC12 methylation and clinical pathological factors in pancreatic cancer.Results The expression of HOXC12 was lost in SW1990,Panc10.05,AsPC1,MIAPaCa2,PANC1,PATU8988T,Capan1,PANC-28 and JF305 cells.And the promoter region of HOXC12 was completely methylated in these cells.The expression of HOXC12 gene was reduced in Panc5.04 cells,and its promoter region was partially methylated.Loss off/reduced expression was correlated to complete/partial methylation.The expression of HOXC12 was restored in SW1990,Panc10.05,AsPC1,MIAPaCa2,PANC1,PATU8988T,Capan1,PANC-28 and JF305 cells after 5-aza-dc treatment.And the repression of HOXC12 was increased in Panc5.04 cells after 5-aza-dc treatment.These results suggested that the expression of HOXC12 was regulated by promoter methylation.Further study found that HOXC12 was methylated in 50.34%(73/145)of pancreatic cancer,and methylation of HOXC12 was associated with age,gender,alcohol consumption and neuro-invasion(all P<0.05),while no association was found between HOXC12 methylation and tumor size,lymph node metastasis and tumor differentiation(all P>0.05).Conclusion HOXC12 gene is frequently methylated in pancreatic cancer and its expression is regulated by promoter methylation.HOXC12 methylation is a potential diagnostic and prognostic marker in pancreatic cancer.