The human APOBEC superfamily consists of eleven cytidine deaminase enzymes. Among them, APOBEC3 enzymes play a dual role in antiviral immunity and cancer development. APOBEC3 enzymes, including APOBEC3A (A3A) and APOBEC3B (A3B), induce mutations in viral DNA, effectively inhibiting viral replication but also promoting somatic mutations in the host genome, contributing to cancer development. A3A and A3B are linked to mutational signatures in over 50% of human cancers, with A3A being a potent mutagen. A3B, one of the first APOBEC3 enzymes linked to carcinogenesis, plays a significant role in HPV-associated cancers by driving somatic mutagenesis and tumor progression. The A3A_B deletion polymorphism results in a hybrid A3A_B gene, leading to increased A3A expression and enhanced mutagenic potential. Such polymorphism has been linked to an elevated risk of certain cancers, particularly in populations where it is more prevalent. This review explores the molecular mechanisms of APOBEC3 proteins, highlighting their dual roles in antiviral defense and tumorigenesis. We also discuss the clinical implications of genetic variants, such as the A3A_B polymorphism, mainly in HPV infection and associated cancers, providing a comprehensive understanding of their contributions to both viral restriction and cancer development.

Natural killer (NK) cells are emerging agents for cancer therapy. Several different cytokines are used to generate NK cells for adoptive immunotherapy including interleukin (IL)‐2, IL‐12, IL‐15 and IL‐18 in solution, and membrane‐bound IL‐21. These cytokines drive NK cell activation through the integration of signal transducers and activators of transcription (STAT) and nuclear factor‐kappa B (NF‐κB) pathways, which overlap and synergize, making it challenging to predict optimal cytokine combinations for both proliferation and cytotoxicity. We integrated functional assays for NK cells cultured in a variety of cytokine combinations with mathematical modeling using feature selection and mechanistic regression models. Our regression model successfully predicts NK cell proliferation for different cytokine combinations and indicates synergy of activated STATs and NF‐κB transcription factors between priming and post‐priming phases. The use of IL‐21 in solution in the priming of NK cell culture resulted in an improved NK cell proliferation, without compromising cytotoxicity potential or interferon gamma secretion against hepatocellular carcinoma cell lines. Our work provides an integrative framework for interrogating NK cell proliferation and activation for cancer immunotherapy.