结肠癌患者外周血DcR3与CEA联合测定的临床价值

目的联合检测结肠癌患者外周血中DcR3与癌胚抗原(CEA)mRNA的水平,建立取材于外周血的早期诊断结肠癌的新方法。方法44例结肠癌患者和30名健康志愿者,各取5 mL静脉血,肝素抗凝,密度梯度离心法分离外周血单核细胞,细胞总RNA TRIzol提取液提取外周血单核细胞总RNA,用半定量RT PCR法检测外周血单核细胞中DcR3与CEA mRNA的水平,并用t检验进行比较。结果结肠癌患者外周血中DcR3基因的相对表达水平为0.415±0.078,与健康对照组(0.235±0.074)比较有显著性差异(P<0.05),但患者之间没有明显差异(P>0.05)。CEA在结肠癌患者外周血中阳性率为36.4%(16/44),表达水平为0.346±0.071。30名健康志愿者均为阴性。结论DcR3基因在结肠癌患者外周血中表达水平明显高于健康人,其表达水平与结肠癌有相关性。在CEA阴性情况下,DcR3可能成为新的肿瘤标志物。

The clinical significance of detecting the level of DcR3 and the expression of CEA mRNA in the peripheral blood of patients with colonic carcinoma

Objective To detect the level of decoy receptor 3(DcR3) and the expression of carcinoembryonic antigen(CEA) mRNA in the peripheral blood of patients with colonic carcinoma,and create a new diagnostic method of early colonic carcinoma.Methods 5 mL venous blood was collected from 44 patients and 30 normal controls into tubes containing sodium heparin aseptically,and the PBMC was isolated by the density gradient centrifugation.The total RNA of the PBMC was extracted by the RNA TRIzol extract.The level of DcR3 in the peripheral blood and the expression of CEA mRNA were detected by using semiquantitative RT-PCR.The significance among different groups was examined by t-test.Results The expression of CEA mRNA in the patients with colonic carcinoma was significantly higher than that in the normal controls(P<0.05);however,the differences among the patients were not significant(P>0.05).The percentage of CEA-positive patients was 36.4%(16/44),and the level of positive CEA in the PBMC was 0.346±0.071;the expression of CEA in PBMC of normal controls was negative.Conclusion The expression of DcR3 gene in the peripheral blood of the patients with colonic carcinoma was significantly higher than that in normal controls.The level of the DcR3 was correlated with the colonic carcinoma.DcR3 might be a new tumor marker when the expression of CEA is negative.