Molecular Detection Of Circulating Cancer Cells With CK-19,CK-20 And CEA Bio-markers In The Peripheral Blood Of Patients With Colorectal Cancer

Background & Objective: Colorectal cancer (CRC) is one of the mostfrequent malignaceies. Approximately 20%-45% of colorectal cancer (CRC) patients ultimately develop local recurrence or metastasis following curative surgical resection. The latter is caused by tumor cells shed from the primary carcinoma prior to or during operation, currently undetected by standard clinical staging. Fortunately, the presence of tumor cells in peripheral blood can be detected by molecular methods and is being regarded increasingly as a clinically relevant prognostic factor.In our research, we aimed to develop a simple, noninvasive, and promising tool for early detection of colorectal cancer and its persibility for postoperative micrometastasis.Methods: ① To detect the presence of circulating tumor cells and evaluate theirrelationship to postoperative metastatic relapse, we simultaneously examined cytokeratin-19 (CK-19), cytokeratin-20 (CK-20), and carcinoembryonic antigen (CEA) mRNA (messenger RNA) in the peripheral blood of 72 CRC patients and 30 healthy individuals. Using a reverse-transcriptase polymerase chain reaction (RT-PCR), these tumor-related mRNAs were amplified; in addition, analyses were carried out for their correlation with patients' clinicopathologic features, as well as the occurrence of postoperative metastasis.②The expression levels of molecular markers in tissue and peripheral blood were evaluated by real-time Q-PCR. The quantity of expression ratio of mRNA markers was normalized to β-actin. Receiver operating characteristics (ROC) curve analyses were carried out to determine cut-off value,...