New Therapy for Cancer

During the last decade due to enhanced knowledgeon the mechanism of tumor biology, immunotherapy of cancer has made significant progresses in treatment of patients with cancers. A major challenge in cancer therapy is the lack of specificity for cancer cells. Treatment with anticancer drugs is commonly categorized into following different types namely chemo/ radiotherapy, which involves a large group of cytotoxic drugs that interfere  with cell division and DNA synthesis; Until recently, most treatments for cancer employed drugs that were poorly selective for cancer cells. As a result, these drugs often failed to work and usually caused severe side effects by killing normal cells too. Hormonal therapy,  which involves agents that interfere with growth signalling through hormone receptors on cancer cells; targeted  therapy, which consists of a novel group of antibodies  and small-molecule kinase inhibitors that specifically  target proteins that are involved in growth signalling  pathways in cancer cells; Despite significant advances in these therapies, a major challenge which remains unaddressed is that these treatment options affect patient’s health-related quality of life in various ways. The lack of effective treatment modalities for many inoperable solid malignancies led to the search of new therapeutic options.  Immunotherapy has recently evolved as a treatment of choice, since these have better specificity, improved efficacy, less side effects as compared to the standard chemotherapy regimens. The idea of cancer immunotherapy is to boost the host’s immune system to fight against cancer more specifically with minimal side effects thereby providing long term benefits. Thusimmuno therapy is the need of the hour and holds much promise for the management of Cancer.

The characteristic of tumor cells is that these have the capacity to escape immune-surveillance and are thought to be inadequate to prime immune responses in host. Our immune system can battle cancer cells usually by invoking an immune response against tumor-specific antigens or against tumor associated antigens (TAA).Recently dendritic cell therapy (DCT) has emerged as an immunotherapy for the treatment of various cancers. It is based on the concept, that the body‘s own guard system can effectively distinguish and kill cancer cells by ex vivo modification and programming of DCs to attack lingering cancer cells. It is a highly personalized treatment which instructs patient's DCs to fight against their tumor load. In this way DCT is a complementary and supportive approach to the prevailing conventional treatment modalities. The treatment protocol involves collection of circulating WBC from the blood by a process known as Leukapheresis. The mononuclear cells so collected aseptically are cultured in specific culture media under strictly controlled conditions for generation of DC. The DCs are then pulsed together with tumor antigen and maturation stimuli for 8 days. Once tumor antigen specific DCs are matured, the formulation would be ready for infusion into patients every 3 to 4 weeks for up to nine months. DCT is generally well tolerated and is not associated with any adverse side effects. After infusion into the patients, TAAs expressed by DCs are recognized by other cellular effector cells particularly T cells that are then travelling through the body and destroy the tumor cells. In this way, DC cancer vaccines elicit a more potent active immunity in the patients in whom the immune surveillance has failed. Ex vivo generated DCs loaded with tumor-specific antigens are capable of stimulating powerful antitumor immune responses, and over 200 clinical trials have been reported. These results pertaining to safety, tolerability and efficacy suggest the potential of dendritic cell vaccine as potent immune regulators in cancer immunotherapy.