Abstract 3917: GenoCTC, a liquid biopsy device using microfluidic enrichment for affinity-based isolation of circulating tumor cells

To achieve a complete remission of cancer is still challenging that most patients with solid cancer ultimately experience metastasis. Detection of circulating tumor cells (CTCs) from the peripheral blood is promising key to solve the cancer cell dissemination and make accurate diagnosis, therefore, many efforts have been made to isolate the CTCs. Here, we newly developed the liquid biopsy device, GenoCTC, with microfluidic chips isolating CTCs from the patient whole blood. To isolate CTCs, EpCAM + CTCs in the whole blood are first bound with magnetic beads conjugated with human-EpCAM antibody, and GenoCTC and its chip can isolate the EpCAM + CTCs through magnetic based method. With 7.5 mL whole blood from lung cancer patient, we isolated EpCAM + CTCs, and these CTCs were validated by immunofluorescence assay using anti-CK and anti-CD45. We also enumerated EpCAM + CTCs in 17 whole blood samples from 10 lung cancer patients that various number, 2 to 114, of CTCs were found from each patient. The number of CTCs is known to have a correlation with disease progression and chemo-resistance, so the clinical meaning of this result is needed to be investigated. Furthermore, some CTCs are also found to be EpCAM independent which is regarded to have clinical utility involved in EMT. We used plastin-3 as its marker, and it was confirmed with HS 578T breast cancer cell line which shows low expression of EpCAM but high expression of plastin-3. The various molecules expressed on CTCs can be isolated with GenoCTC for further study. The characterization of CTCs is not only limited to EpCAM expression that it is important to be elucidated the complex biology of CTCs to apply companion diagnosis for personalized medicine. Citation Format: Jiyeon Ryu, Do Hyung Kim, Gyeong-Mi Kim, Jin Soo Kim, Youngkee Shin, Jaeku Lee, Hun Seok Lee. GenoCTC, a liquid biopsy device using microfluidic enrichment for affinity-based isolation of circulating tumor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3917. doi:10.1158/1538-7445.AM2017-3917