Cancer cells escape the immune surveillance mechanism before they manifest as tumors. Antigenic modulation, antigen masking, and over production of tumor promoters such as transforming growth factor β are some of the well-studied escape mechanisms. Targeting the immunological escape process is the basis of immune-oncology treatments.
Multiple strategies to stimulate and enhance the immune systems response to tumors are currently being designed and evaluated in clinical trials. These include checkpoint inhibitors, chimeric antigen receptor (CAR) T-cell therapy, cytokines, immune-modulators, cancer vaccines, monoclonal antibodies and oncolytic virus.
Uncontrolled immune response to a pathogen or any abnormal protein can cause tissue damage and autoimmune diseases. The immune system has a regulatory mechanism to control immune response which is commonly referred to as immune checkpoint. Cancer cells evade detection and elimination by activating these checkpoints and suppressing the anti-tumor response.
Cytokines in Cancer Immunotherapy
Cytokines are potent and complex immune mediators. A delicate balancing dance between the different stimulating and antagonistic cytokines determine the end result. As they have a limited half-life, they are short-lived, thus exerting autocrine or paracrine effect.
Studies have shown that cells from the immune system can specifically recognize and destroy cancer cells. Cytokines are secreted by cells from the immune system, hence they have been explored in treatment of cancer.
Cytokines in monotherapy have not been successful, hence a combination of cytokines with checkpoint inhibitors, anticancer monoclonal antibodies to increase the antibody-dependent cellular cytotoxicity of the antibodies (ADCC), anti-cytokine fusion proteins and anti-CD40 are being explored .
Immuno-stimulatory cytokines that help the fight against cancerIFN-α IL-2 IL-10 IL-12 GMCSF
Immunosuppressive cytokines in cancer therapyTNFα TGF-β CSF-1