text: Recent studies show that proliferative and invasion-competent circulating tumor cells (CTCs) are invaluable in many downstream applications that depend on the ability of the isolated tumor cells to recapitulate tumor growth and metastasis in xenograft mouse models. The long-term objective of this proposal is to convert the existing Vitatex CTC preparation tube to a closed vacutainer system that is capable of collecting blood, as well as preserving and immobilizing proliferative and invasion-competent cancer cells in blood for up to 96 hours of transit. This Phase I proposal aims to: (1) identify the cocktail of survival factors for captured CTCs in an experimental (spiking) setting using blood of healthy women, (2) develop SOP methods for isolating CTCs in blood of ovarian cancer patients within vacutainer-adapted tubes to analyze for recovery, viability, and function, and (3) assess proliferative and invasive capabilities of isolated CTCs using MTT, ATP determination and collagen uptake and spherogenic assay to determine tumorigenicity. The goal is to define conditions that promote the survival of tumor cell populations in blood that retain some degree of proliferative capacity. Viable CTCs isolated using such methods can then be used ex vivo for selection of treatment tailored to individual patients.