Current Strategies for Modulating Tumor-Associated Macrophages with Biomaterials in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fourth most common cause of cancer-related deaths in the world. However, there are currently few clinical diagnosis and treatment options available, and there is an urgent need for novel effective approaches. More research is being undertaken on immune-associated cells in the microenvironment because they play a critical role in the initiation and development of HCC. Macrophages are specialized phagocytes and antigen-presenting cells (APCs) that not only directly phagocytose and eliminate tumor cells, but also present tumor-specific antigens to T cells and initiate anticancer adaptive immunity. However, the more abundant M2-phenotype tumor-associated macrophages (TAMs) at tumor sites promote tumor evasion of immune surveillance, accelerate tumor progression, and suppress tumor-specific T-cell immune responses. Despite the great success in modulating macrophages, there are still many challenges and obstacles. Biomaterials not only target macrophages, but also modulate macrophages to enhance tumor treatment. This review systematically summarizes the regulation of tumor-associated macrophages by biomaterials, which has implications for the immunotherapy of HCC.

Automated summary

Hepatocellular carcinoma (HCC) is a major cause of cancer-related deaths worldwide, with limited clinical diagnosis and treatment options. Research on immune-associated cells in the microenvironment, particularly macrophages, is being undertaken to develop novel effective approaches for HCC. Macrophages play a critical role in phagocytosing tumor cells, presenting tumor-specific antigens, and initiating anticancer immune responses. However, the presence of M2-phenotype tumor-associated macrophages (TAMs) at tumor sites promotes immune evasion, tumor progression, and suppression of tumor-specific T-cell immune responses. Biomaterials offer potential solutions to modulate and target macrophages for enhanced HCC immunotherapy.