Clinical significance of CEA mRNA expression in peripheral blood of patients with colon cancers

OBJECTIVE:To detect the expression of carcinoembryonic antigen (CEA) mRNA in peripheral blood samples of patients with colon cancers by RT-PCR and to explore the relationship between CEA mRNA expression and different clinical pathological indexes and to evaluate the significance of CEA mRNA expression in early prediction. METHODS: CEA mRNA was detected with RT-PCR by using CEA-specific primers in peripheral blood of 29 patients with colon cancers. The CEA and carbohydrate antigen 19-9 (CA19-9) glycoproteins were detected in the peripheral blood of those patients at the same time and, 12 healthy volunteers were selected as control. RESULTS: The positive rates of CEA mRNA, CEA, CA19-9 were 24.14%(7/29), 17.24%(5/29), 13.79% ( 4/29), respectively, in peripheral blood of 29 patients. CEA mRNA, CEA, CA19-9 in the control was all negative. The positive rate of CEA mRNA of patients with lymph nodes metastasis (35.29%, 6/17) was higher than that of patients without lymph nodes metastasis (8.33%, 1/12) (χ~2=2.79,P=0.095). The positive rates of CEA mRNA in Ⅲ, Ⅳ,Ⅰand Ⅱstages were 66.67%(4/6), 16.67%( 2/12), 9.09%(1/11), respectively, and the difference was significant (χ~2=7.65,P=0.022). There was no difference of CEA expression in peripheral blood among ages, sexes and pathological types (P0.05). CONCLUSIONS: The positive rate of CEA mRNA is the highest among CEA mRNA, CEA and CA19-9 in patients with colon cancers. The higher clinical stages of the cancers, the higher of the positive rate of CEA mRNA is. The positive expression of CEA mRNA indicates the poor prognosis and should be treated positively.