The role of the immune system in the control of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is common, and current therapies may not be suitable for the majority of patients with advanced disease. Cases of spontaneous regression suggest that immune mechanisms are important in the control of HCC. Experiments in animal models have shown that tolerance to HCC associated antigens can be overcome and using a number of different techniques researchers have been able to prevent the growth of implanted tumours. The most promising of these techniques is based on the use of dendritic cells, which are able to process and present antigens to activate naive T cells and, when loaded with tumour antigens, can stimulate a specific and durable anti-tumour response. The success of animal studies has led to interest in the clinical applicability of HCC immunotherapy. Non-specific adoptive immunotherapy has been successful in preventing disease recurrence after resection and cellular vaccines based on dendritic cells are now entering clinical trials. The use of dendritic-cell vaccination raises exciting possibilities of preventing the formation of HCC in high-risk individuals such as those with cirrhosis.