PIK3R1 and type 2 diabetes mellitus: The protein–protein interaction (PPI) and target–pathway (TP) network analysis identified key hub genes, including EGFR, SRC, AKT1, TNF, PPARG, PIK3R1, RELA, INSR, GSK3B, PIK3CG, FYN, PTBIN, and PPARA, with critical roles in insulin resistance and T2DM-relevant pathways.