MEF2B and posterior cortical atrophy: By evaluating copy number alterations in ATM mutant PCa vs. HR-proficient, HR-deficient or BRCA2 mutant PCa, Ryan et al. reported that ATM-mutated PCa displays copy number alterations for the FGF19, FGF4, PTPN11, ALDH2, DAXX, BCL7A, CCND1, BMPR1A and MEF2B genes, suggesting that FGF- and PTPN11-related pathways are potentially targetable pathways in ATM mutant PCa [51].