PIK3CA and cancer: The regulation of cancer cell development by PSMC genes has been studied in multiple cancers but rarely in LUAD, and their function as oncogenes was found to be correlated with dysfunctions in the cell cycle (Liu Y. et al., 2021), PI3K/AKT/mTOR (Zhang Y. et al., 2020; Wang et al., 2022), MAPK (Jang et al., 2015), and EMT pathways (He et al., 2021).