• HEPATOCELLULAR CARCINOMA
• CANCER IMMUNOBIOLOGY
• TGF-BETA
• IMMUNOREGULATION
• MACROPHAGES

Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide due to its emergence based on chronic liver disease. Thus, HCC can ultimately be caused by multiple factors, including chronic viral infection, alcohol abuse or obesity. Nevertheless, only a few therapeutic options are available, especially for patients in later stages of disease.1 Accordingly, prognosis of patients is often poor and HCC contributes disproportionately to cancer-related deaths worldwide. Thus, further research into HCC is required to inform the development of novel therapies as well as improvements to existing regimens. An important focus of current research into tumours in general, and HCC in particular, is the microenvironment in which development and progression of a tumour occurs. The tumour microenvironment comprises multiple cellular and non-cellular components and has been shown to be an important determinant of tumour progression, patient prognosis and thus also a determinant of therapeutic success in HCC and elsewhere.2 Indeed, some of the therapeutic effects of sorafenib, to date the only approved small-molecule inhibitor for treatment of advanced HCC, may be attributable to its effects on the tumour microenvironment.3 Among the different cell types found in the tumour microenvironment, macrophages, so-called tumour-associated macrophages (TAM), are among the most common. TAM typically differ from normal macrophages in their shift to an alternatively activated (M2) …