Molecular detection of cancer cells by RT-PCR

1.用RT-PCR法分析了癌胚抗原(CEA)、雌激素受体(ER)和MAGE在肿瘤组织和正常上皮组织中的表达。CEA几乎在所有肿瘤和正常上皮组织中均可检测到。1/3的样品中可检出内质网。MAGE在正常上皮组织中不表达，但在10-60%的肿瘤组织中表达。结果表明，CEA基因是最佳的靶基因。2.CEA基因的阳性检出率由组织学检查的20%上升到RT-PCR的60%，其中37例组织学检查均为阳性，复发率为35%，47例组织学检查阴性但RT-PCR阳性的患者复发率为8%，18例两项检查均为阴性。62例根治性手术患者中有12例检测到CEA mRNA。这12例中有4例术后发生转移，而RT-PCR阴性的50例中无一例发生转移。4.已证明RT-PCR是检测淋巴结或外周血CEA基因表达的有力工具。这可能对确定高危患者的转移非常有用。

1.We analyzed the mRNA expression of carcinoembryonic antigen (CEA), estrogen receptor (ER) and MAGE in tumor and normal epithelial tissues by means of PT-PCR.CEA was detectable in almost all tumor and normal epithelial tissues. ER was detectable in 1/3 of the samples. MAGE was not expressed in normal epithelial tissues, but was expressed in 10-60% tumor tissues. The results indicated that the best target gene was CEA.2.The positive detection rate increased from 20% by histologic examination to 60% by RT-PCR.The recurrence rate was 35% in 37 cases showing positive results in both examinations, 8% in 47 cases showing histologically negative but RT-PCR positive results, and none in 18 cases showing negative results in both examinations.3.The positive detection rate for CEA mRNA in peripheral blood samples increased with advancing stage of disease. With respect to 62 curatively operated cases, CEA mRNA was detected in 12 cases. Four of these 12 cases developed metastatic disease after surgery whereas none of 50 cases negative by RT-PCR developed metastasis.4.It has been shown that RT-PCR is a powerful tool to detect CEA mRNA in the lymph nodes or the peripheral blood. This is potentially very useful to determine high-risk patients for metastasis.