Novel In Vivo Flow Cytometry And Its Application In The Study Of Circulating Tumor Cells

The cancer cells from malignant tumor are capable of establishing new tumors in locations remote from the site of the original disease by travelling through the body. A cancer cell must break away from the original tumor, then invade either the circulatory or lymph system to metastasize. The system will carry the cell to other organs, and it may establish itself in a new site. In the circulatory system, the cancer cells are able to access to any portion of the body.In order to study the pontential relationship between metastatic capability and depletion kinetics of circulating tumor cells, we prenset the "in vivo flow cytometry". The in vivo flow cytometry can be used to detect and quantify the number and flow characteristics of fluorescently labeled cells continuously in vivo. We built an in vivo flow cytometry and measured the depletion kinetics of two kind of liver cancer cells, one with metastatic potential to lung while the other one without the pontential. Interestingly, more invasive HCCLM3 cancer cells deplete faster from the circulation than HepG2 cells. Over 60% HCCLM3 cells are depleted within the first hour after injection. In comparison,<40% HepG2 cells are depleted within the first hour. The HepG2 cells possess noticeably slower depletion kinetics. In adddition, we have examined the cell increasement in skull bone marrow zone, liver and lung by laser scanning confocal microscopy. The differences of depletion kinetics between high metastatic potential cells and non-metastatic cells might provide insights into early metastasis processes.