Detection Of Circulating Cancer Cells By Nested RT-PCR In Patients With Gastric Cancer And Significance.

Objectives To study the expressions of CK20 mRNA in patients with gastric cancer in peripheral blood and it's significance.Methods The expression of CK20 mRNA in peripheral blood specimens of 50 patients with gastric cancer, 10 patients with benign gastric disease, 10 healthy donors were studied by nested RT-PCR, and the established cell line of HT-29 cells used as the positive control.Results The results showed that the expression rate of CK20 mRNA in peripheral blood specimens of patients with gastric cancer was 48%(24/50), There were no expression of CK20 mRNA in 10 patients with benign gastric disease and 10 healthy donors. The expression rate of CK20 mRNA in peripheral blood specimens of patients with gastric cancer was related to the differentiation degree, the dimension of tumor, the clinical substage and the depth of infiltration(P＜0.05), with the dimension of tumor,the clinical substage and the depth of infiltration increasing, the expression rate of CK20 mRNA increased accordingly,the expression rate was inversely proportional to the differention degree.But no significant correlations were found between the CK20 mRNA expression and primary tumor site, the sex and age of patients(P＞0.05). Conclusion The expression rate of CK20 mRNA in peripheral blood specimens of patients with gastric cancer was related to the differentiation degree, the dimension of tumor, the clinical substage and the depth of infiltration. but there were no significant correlation between the CK20 mRNA expression and primary tumor site,the sex and age of patients. The circulating gastric cancer cells can be detected efficiently by nested RT-PCR. Detecting the expression of CK20 mRNA may contribute to early discovery of micrometastases. Early diagnosis of micrometastases has help in choosing appropriate time of therapy,evaluating the effect of therapy,adjusting treatment, judging prognosis.