As a paradigmatic example, a recent study exploiting in vivo CRISPR‐Cas9 screening identified the COX‐2/PGE2 axis as a major mechanism shaping the TME in KRAS‐induced lung adenocarcinoma, since oncogenic KRAS triggered COX‐2 overexpression in cancer cells to alter tumor immunity. The gene discussed is KRAS; the disease is lung adenocarcinoma.