CDK4 and neoplasm: A high nuclear CDK2/low nuclear CDK4 co-expression showed a significant association with a younger patient age (p = 0.03), high tumour grade (p < 0.0001), low tubule formation (p = 0.004), high degree of nuclear pleomorphism (p < 0.0001) and high mitosis (p < 0.0001), NST tumour type (p < 0.0001), HER2-enriched molecular subtype (p < 0.0001), poor NPI groups (p < 0.0001), and high Ki67 expression (p < 0.0001) (Supplementary Table S6).