PIK3R1 and posterior cortical atrophy: For instance, Gao et al. [59] established in vitro models of PCa derived from metastatic tumors and circulating tumor cells, and they revealed that these organoid lines recapitulated copy number signatures of original PCa, such as TMPRSS2–ERG fusion, SPOP mutation, PTEN loss, and CHD1 loss, as well as genomic alterations frequently detected in mCRPC including TP53, PIK3R1, and FOXA1.