CRISPR-based large-scale modeling of loss-of-function mutations to investigate mechanisms of stress resistance in cancer.

Dissecting mechanisms driving subclone expansion in primary cancers has been challenging. Here, we present a protocol to systematically disrupt entire gene networks and assess the functional impact of this perturbation on cancer cell fitness. By combining arrayed CRISPR libraries and high-content microscopy, we describe steps to identify classes of genes whose inactivation promotes resistance to environmental challenges faced by cancer cells during tumor growth or upon therapy. A proof-of-principle interrogation of the epigenetic regulatory network is described. For complete details on the use and execution of this protocol, please refer to Loukas et al. (2022).1.