Abstract:

The immune microenvironment of hepatocellular carcinoma (HCC) is mainly composed of tumor-associated macrophages, myeloid-derived suppressor cells and other cellular components, as well as extracellular components, such as cytokines, growth factors and extracellular matrix, etc. In China, most liver cancer patients are complicated with chronic hepatitis B and cirrhosis. Immune microenvironment promotes the incidence and progression of HCC, immune escape and treatment resistance, and exerts immunosuppressive effect. In recent years, significant progress has been made in immunotherapy for systemic treatment of HCC, such as immune checkpoint inhibitors (ICIs). However, in the KEYNOTE-240 and CheckMate 459 trials, anti-PD-1 therapy with nivolumab or pembrolizumab as a single drug failed to reach the expected overall survival endpoint. At present, it is urgent to deepen the understanding of immune microenvironment of HCC and explore novel therapies to improve clinical efficacy of ICIs. Currently, the combination of ICIs with other therapies (such as tyrosine kinase inhibitors, monoclonal antibodies or local therapy) has been proven to improve the efficiency of single ICIs. In this article, research progress in immune microenvironment, immunotherapy and immune combined with targeted therapy for HCC was reviewed.

Key words: Carcinoma, hepatocellular, Immune checkpoint inhibitors (ICIs), Programmed death receptor 1 (PD-1), Vascular endothelial growth factor (VEGF), Immunotherapy