Detection of cancer cells in mesenteric and peripheral veins by measuring telomerase activity in colorectal cancer patients

作者：Hioaki Nozawa, Taku Watanabe, Tetsuo Ohnishi, Taku Tada, Giichirou Tsurita, Susumu Sasaki, J. Kitayama, Hirokazu Nagawa · 发表于：Journal of Clinical Oncology · 年份：2004 · DOI：10.1200/jco.2004.22.14_suppl.3628 · 研究领域：Telomeres, Telomerase, and Senescence

3628 Background: Liver metastasis is an important factor that determines prognosis in colorectal cancer (CRC). Several attempts such as RT-PCR analyses of certain genes have been applied for detecting cancer cells since their shedding into the drainage veins is considered the initial step of metastasis. In this study, we measured telomerase activity to assess the existence of malignant cells in the drainage veins and further examined if its detection is correlated with synchronous and metachronous liver metastasis. Methods: Blood samples were collected from mesenteric (tumor-drainage) vein and peripheral vessels in 41 CRC patients before mobilizing the tumor-bearing segment. Peripheral blood samples from 6 healthy people were served as negative controls. ELIDA-linked TRAP assay in combination with immunomagnetic sorting was employed for measuring telomerase activity. The activity was calculated as relative telomerase activity (RTA; %) against a known amount of a control telomeric repeat template. All the patients have been followed up until 12 to 24 months after the initial operation. Results: RTA of mesenteric blood sample was higher in patients with synchronous and/or metachronous liver metastasis (47.3; n=9) than in metastasis-free patients (21.0; n=32, p=0.12). The RTA of peripheral blood sample also tended to be higher in the patients with liver metastasis (22.4) than in those without metastasis (11.4, p=0.20). On the other hand, the average and maximum RTAs of blood fro...