2009 Fiscal Year Final Research Report

Detection of circulating tumor cells in breast cancer utilizing new direct method and biological analysis

Research Project

Project/Area Number	19591500
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	General surgery
Research Institution	Hokkaido University
Principal Investigator	TAKAHASI Masato Hokkaido University, 病院, 助教 (50374343)
Project Period (FY)	2007 – 2009
Keywords	乳癌 / ISET / 遺伝子解析 / 遊離癌細胞
Research Abstract	Exact identification of circulation tumor cells (CTC) brings the choice of patients who should take heavy treatment. As a result, Survival will be improved. At first, we confirmed the detection of very small number of breast cancer cells in blood by the isolation by size of epithelial tumor cells (ISET) method. The next, we compared the sensitivity of ISET method with that of quantitative real-time RT-PCR assay for the evaluation of CK-19 mRNA expression. The sensitivity of ISET was not comparable with those obtained using RT-PCR. Immunohistochemistry of ER, PgR, HER2 on the filter of ISET showed same behavior like the original cell lines. The DNA extracted from ISET-positive filter could detect the mutation of p53 using direct sequence method. HER-2 amplification could be measured by FISH analysis. Unfortunately none of 17 breast cancer samples from peripheral blood and bone marrow just before surgical operation, showed the presence of CTC cells on the filter of ISET method. Some devices for sensitivity improvement of ISET method should be required in the future.