PIK3CA and neoplasm: We evaluated hallmark enrichment across MSig subtypes and found: (1) C2 and C4 generally exhibited opposite hallmarks in many aspects, such as in the immune category; (2) C5 showed significant enrichment in tumour‐driving signalling, such as PI3K/ATK/MTOR and NOTCH pathways; (3) C3 was identified as a transitional state (Figure 5C; Table S16).