Fig. 3: Therapeutic strategies in mesothelioma classified according to their mode of action.

Immune checkpoint inhibitors block signalling that suppresses immune-cell activity, such as PD-1–PD-L1 and B7-1/2–CTLA-4 interactions, which is upregulated by tumour cells. Tumour-associated antigens (TAAs) can be targeted using monoclonal antibodies against proteins such as mesothelin, by vaccine therapy to stimulate the immune response and by using antibody–drug conjugates (ADCs) that target proteins such as mesothelin, 5TA, CD26 and CD30. Autologous dendritic cells pulsed with autologous or allogeneic tumour cell lysate act to prime host immunity, while chimeric antigen receptor CAR T cells contain chimaeric receptors that have been generated to specifically bind to TAAs on the cell surface. Other therapeutic approaches include oncolytic viruses that directly kill cancer cells by lysis or indirectly by stimulating immune response. They have been engineered to increase viral specificity (by introducing TAAs), cytotoxicity (by introducing e.g. pro-apoptotic or immunostimulatory genes), and monitoring (by introducing reporter genes).