Exploiting the immune system in hepatic tumor targeting: Unleashing the potential of drugs, natural products, and nanoparticles.

Hepatic tumors present a formidable challenge in cancer therapeutics, necessitating the exploration of novel treatment strategies. In recent years, targeting the immune system has attracted interest to augment existing therapeutic efficacy. The immune system in hepatic tumors includes numerous cells with diverse actions. CD8+ T lymphocytes, T helper 1 (Th1) CD4+ T lymphocytes, alternative M1 macrophages, and natural killer (NK) cells provide the antitumor immunity. However, Foxp3+ regulatory CD4+ T cells (Tregs), M2-like tumor-associated macrophages (TAMs), and myeloid-derived suppressor cells (MDSCs) are the key immune inhibitor cells. Tumor stroma can also affect these interactions. Targeting these cells and their secreted molecules is intriguing for eliminating malignant cells. The current review provides a synopsis of the immune system components involved in hepatic tumor expansion and highlights the molecular and cellular pathways that can be targeted for therapeutic intervention. It also overviews the diverse range of drugs, natural products, immunotherapy drugs, and nanoparticles that have been investigated to manipulate immune responses and bolster antitumor immunity. The review also addresses the potential advantages and challenges associated with these approaches.