In vivo gain-of-function cDNA library screening for colonization genes in a mouse model of pulmonary metastasis.

We provide a protocol for gain-of-function (GOF) cDNA screen of genes that foster cancer cell colonization of secondary tissues, the last and most lethal step of the metastasis cascade. We present techniques for cDNA viral library preparation and delivery leading up to the recovery of colonization-promoting sequences in a proof-of-concept DU145-based mouse model of pulmonary metastasis. Adapted to other cDNA libraries and cancer models, this approach would prove widely useful in enumerating intrinsic genetic determinants underlying metastatic colonization. For complete details on the use and execution of this protocol, please refer to Tu et al. (2021).