Cancer immunotherapy which is studied intensely in preclinical studies and being applied in clinics, is one of the adjuvant therapies for cancer in modern medicine. Use of monoclonal antibodies is more common in clinics in cancer immunotherapy compared to cancer vaccines and cellular therapies.

Monoclonal antibodies targeting overexpressed and tissue specific receptors or growth factors in cancer cells are most common and clinically approved application of cancer immunotherapy. Currently for cancer immunotherapy, there are at least 12 approved monoclonal antibodies in clinical use. These monoclonal antibodies are being utilized for the therapy of breast cancer, lung cancer, colorectal cancer, renal cell cancer and several lymphomas and leukemias. Monoclonal antibodies used in cancer immunotherapy target factors supporting cancer progression such as vascular endothelial growth factor, epidermal growth factor and human epidermal growth factor 2; and target tissue specific differentiation antigens in tumor cells such as CD20 and CD52.

The methodology of monoclonal antibody production is based on the immunization of mice with specific antigens, and on the generation of hybridoma with myeloma cancer cells and B lymphocytes. The new class of drugs was born with this technique and can be described as a revolution in the medicine and monoclonal antibodies have been used to treat various diseases, including cancer.

The effectiveness of monoclonal antibodies on the cancer immunotherapy is based on the three main mechanisms. These mechanisms contain i) the antibody binding mediated inhibition of the factors and receptors which stimulate the signaling pathways used in the proliferation and angiogenesis of cancer cells, ii) antibody-dependent cellular cytotoxicity (ADCC), and iii) activation of complement by complement dependent cytotoxicity (CDC).

As a result, the new target proteins involved in cancer development and progression are being identified continuously in the pre-clinical studies, and the studies of monoclonal antibody production that could be effective against them and clinical phase studies are being continued.