Exploring Candidate Human Synthetic Lethal Interactions Through siRNA and Quantitative Imaging-Based Approaches.

Synthetic lethal interactions can assist in characterizing protein functions and cellular processes, but they can also be used to identify novel drug targets for the development of innovative cancer therapeutic strategies. Despite recent technological advancements including CRISPR/Cas9 approaches, the systematic assessment of all pairwise gene interactions in humans (~ 200 million pairs) remains an unmet goal. Thus, hypothesis-driven approaches, which prioritize subsets of promising candidate SL interactions for experimental assessment, are critical to expedite the identification of novel SL interactions. Here, we provide a guide to screen and validate focused libraries of promising candidate SL interactions, typically consisting of 50-500 targets. First, we describe two siRNA and image-based screening protocols to rapidly assess candidate SL interactions. Subsequently, we provide methods to validate a subset of the most promising interactions uncovered in the screens. These approaches employ commercially available reagents and standard laboratory equipment to facilitate and expedite the identification of bona fide human SL interactions.