Furthermore, CRISPRi experiments in other cancer cell types (AML, CML, pancreatic cancer and lung cancer cell lines54–56) demonstrated that, unlike PSMA1, which is a positive control commonly essential gene, PTGES3 is not an essential gene upon knockdown (Extended Data Fig. 10d–g). This evidence concerns the gene PSMA1 and chronic myelogenous leukemia, BCR-ABL1 positive.