EGFR and non-small cell lung carcinoma: In other studies, genome-wide CRISPR/Cas9 screening was performed on H460, H1299 and A549 cell lines that contain wild-type EGFR genes and identified the enzyme phosphoribosylaminoimidazole carboxylase/phosphoribosylaminoimidazole succinylcarboxamide synthetase (PAICS), which is essential for de novo purine biosynthesis and tumor growth, as a potential drug target for EGFR wild-type NSCLC [55].