The discrepancy between organoid and immortalized cell line cultures for cancer target discovery remains unclear. Here, our multi-tiered clustered regularly interspaced short palindromic repeats (CRISPR) screens reveal in vivo-relevant metabolic dependencies and synthetic lethal pairs that can be uncovered with tumor organoids but not cell lines or even three-dimensional (3D) spheroids. These screens identify lanosterol synthase and acetyl-coenzyme A (CoA) carboxylase inhibitors as effective treatments that impede xenografted tumor growth in mice. These lipid metabolic inhibitors exhibit nanomolar half-maximal inhibitory concentration (IC50) values across diverse human gastric cancer organoids resistant to first-line treatments. Mechanistically, gastric cancer organoids and in vivo tumors exhibit lipid metabolic adaptations not seen in two-dimensional (2D) in vitro cultures. Additionally, enteric neurons modulate lipid metabolism in tumor organoids, altering drug sensitivity by up to two orders of magnitude. A neuron-cocultured CRISPR screen further reveals that acetyl-CoA carboxylase expression determines lanosterol synthase inhibitor efficacy. These findings highlight the critical roles of organoid environment and neuronal interaction in cancer lipid reliance.
Chan et al. (Mon,) studied this question.