doi:?10.1016/j.cmet.2014.04.003. an opportunity to interrogate processes that cannot be accurately modeled processes in higher vertebrates has been limited by the high cost and effort-intensive nature of these studies, limited quantities of compounds in chemical libraries, and technical variability in group-to-group comparisons. Chemical screens in and have recognized modulators of several biological processes3-5 and fresh technologies allow the effectiveness of multiple chemotherapeutics to be tested simultaneously in tumors6,7. Nonetheless, large-scale mouse model. We used molecular barcoding combined with high-throughput sequencing to perform multiplexed analysis of compound pretreated cells. Molecular barcoding of cells has been used to track varied sub-clones of malignancy cells and hematopoietic stem cells as well as to monitor reactions to chemotherapy and analyses, most studies have focused Xanthopterin on optimization of compounds with known focuses on21 or assays to identify inhibitors of migration or invasion. While the second option approaches have become higher throughput22, assays likely fail to accurately recapitulate the entire process23. Here, we describe the development and initial software of a multiplexed screening platform that bridges the space between high-throughput cell-based chemical testing and modeling of metastatic seeding. RESULTS Development of the multiplexed screening workflow To allow multiplexed compound testing, we generated 96 distinctively barcoded isogenic variants of a pancreatic malignancy cell collection (Fig. 1a and Supplementary Fig. 1). These variants can each become pretreated with a single compound multiplexed small molecule screening platform to interrogate metastatic seeding(a) Schematic of the multiplexed small molecule display. (b) Screening 712 small molecule irreversible inhibitors at 10 M distributed across twelve 96-well plates. Each plate contained 26 DMSO wells as internal settings (green dots). All compound plates were tested in triplicate on three different barcode-layout plates. Each black dot Xanthopterin represents the average loss of representation of one compound. The reddish line shows a 40% loss of Metastatic ability (~ 3 times the standard deviation of vehicle only treated control). (c) Standard deviation of the triplicate ideals for each compound is proportional to the metastatic ability for those screened compounds,. r is the determined Pearson correlation coefficient. The dotted collection shows the best-fit collection. (d) Metastatic selectivity of the 712 compounds. We chose a murine PDAC liver metastasis cell collection (0688M) that was derived from the well-established pretreatment without the need for continued dosing. Furthermore, these compounds can be converted into activity-based probes (ABPs) for downstream Mapkap1 target recognition using proteomics. Using the multiplexed screening platform, we assessed the anti-metastatic effect of 712 compounds, including internal settings, in triplicate using only 36 mice (Fig. 1b). At the initial screening concentration of 10 M, approximately 5% of the compounds (39) reduced metastatic ability below the threshold of 60% and the assay exhibited well-behaved multiplicative errors with the standard deviation proportional to the metastatic ability (r = 0.81; Fig. 1c). To exclude cytotoxic compounds, we performed viability assays in parallel. We determined Xanthopterin the metastatic selectivity for each compound as the portion of loss of representation that is not attributable to reduced cell growth (Fig. 1d, Supplementary Fig. 2b, Supplementary Table 1). Hit prioritization and dose-dependent Xanthopterin secondary screening Nineteen compounds were Xanthopterin chosen for further dose-response studies (6 concentrations from 10 M to 0.31 M) using metastatic selectivity, structural diversity, viability, and magnitude of effect on metastatic ability as criteria for prioritization (Supplementary Furniture 1, 2). Our multiplexed screening strategy allows the simultaneous analysis of multiple lead compounds at different concentrations in individual mice (Supplementary Fig. 4a). By carrying out.