T-cell response against cancer – immunotherapy today and tomorrow

Besides the three traditional treatment modalities and targeted therapies, immunotherapy of cancer is rapidly emerging as the fi fth pillar of oncology. Tumours appearing on the clinical horizon have successfully evaded or suppressed naturally arising antitumour immunity; the aim of immunotherapy is to beat this immunoresistance and enhance the tumour-killing potency of immune cells. Orchestrating the anticancer immune response are effector T cells and antigen presenting cells (APCs) that instruct them; the latter can be tumour cells themselves or dendritic cells as professional APCs. Therapeutic strategies to boost antitumour T cell response include i) collection, genetic modifi cation and re-infusion of autologous T cells, ii) selection of most effi cient tumour-infi ltrating lymphocytes from the autologous pool, iii) reversing inhibition of T cells by the tumour microenvironment, and iv) presentation of tumourassociated neoantigens to T cells via loaded APCs. This review summarises cancer immunotherapies in the clinic or in human phase clinical trials. Since some of these has achieved durable and complete responses in patients who progressed on multiple prior regimens, immunotherapy – alone or combined with other treatments – is gradually fi nding its way into the fi rst line of cancer therapy.