Detection of cytokeratin20 mRNA in peripheral blood from colonic cancer patients by fluorescence quantitative polymerase chain reaction / 中华肿瘤杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the expression level of cytokeratin20 mRNA (CK20 mRNA) of cancer cells in peripheral blood from colorectal cancer patients, detected by fluorescence quantitative polymerase chain reaction (FQ-PCR), and to evaluate its clinical value.</p><p><b>METHODS</b>To systemically study the reproducibility, quantitative range and amplification efficiency of CK20 mRNA detection by FQ-PCR, analyze and compare the result consistency with conventional RT-PCR and immunohistochemistry, separately. The expression level of CK20 mRNA of cancer cells in peripheral blood was examined in 136 colorectal cancer cases with or without hepatic metastasis.</p><p><b>RESULTS</b>The within-run and between-run CV of FQ-PCR to assay CK20 mRNA were 3.6% and 5.3%, respectively, quantitative range was from 10(3) copies/ml to 10(8) copies/ml and amplification efficiency was 87.4%. Comparing with traditional RT-PCR and immunohistochemistry, the Kappa value was 0.87 and 0.83, respectively. The expression level of CK20 mRNA of cancer cells in peripheral blood from colorectal cancer patients was (3.52 +/- 1.47) x 10(4) copies/ml, and the expression positive rate was 48.5%. None was found among the 75 cases in the control group. The positive rate of CK20 mRNA of cancer cells in peripheral blood was 9.5%, 25.0%, 48.8% and 87.5% in the patients at Dukes stage A, B, C and D, respectively (P < 0.05). The positive rate of CK20 mRNA was 87.5% in patients with hepatic metastasis and 32.3% in patients without hepatic metastasis (P < 0.05). CK20 mRNA showed a tendency to decline in 35 cases of colorectal cancer within the 1st, 3rd and 5th week after operation. There was no difference among the data of pre-operation cases and on the 1st, 3rd week (P > 0.05), but a significant difference between pre-operation and the 5th week (P < 0.05).</p><p><b>CONCLUSION</b>FQ-PCR is a rapid and sensitive method for quantitating CK20 mRNA. The expression of CK20 mRNA of cancer cells in peripheral blood from colorectal cancer patients has a correlation with recurrence and metastasis of the tumors. Detection of CK20 mRNA is helpful to monitor hematogenous dissemination of colorectal cancers.</p>