An in vivo CRISPR screen identifies stepwise genetic dependencies of metastatic progression

In vivo genome-wide loss-of-function CRISPR screen identifies critical genes required for individual steps of the metastatic cascade in human CTC-derived xenografts, suggesting novel drivers and vulnerabilities of breast cancer metastasis. We isolated cells from Bone, Brain, Liver and Lymphnode metastases from a breast cancer xenograft (BR16), after bioluminescence imaging of organs with metastasis conducted with IVIS Lumina II (Perkin Elmer). mRNA was isolated and amplified according to the Smart-Seq2. Subsequently, libraries were prepared with Nextera XT (Illumina) and sequenced on NextSeq75, single read for RNA