Description

ABSTRACT

Toxicity remains a major issue with current anticancer agents due to non-selective action. Immunotherapy is a profound development in anti-cancer treatment due to its ability to deliver therapy to specific cellular targets. Cancer immunotherapy is based around the concept of helping the immune system to recognize and attack certain cancer cells. The cancer-killing properties oncolytic viruses are supported by observations that in case of the chickenpox infection which brought back the WBC count and lymph node status in patients with lymphocytic leukemia. Measles improved in the prognosis of leukemia, Hodgkin’s, and Burkitt’s lymphoma. The viruses kill neoplastic cells as well as trigger already existing but ineffective anti-tumor immune response against the tumor. Virus infection of a tumor cell results in the virus making copies of it until the cell bursts. The dying cancer cell releases materials, such as tumor antigens, that allow the cancer to be recognized, by the immune system. Numbers of researchers are working in this field to utilize virus to bring novel therapeutic options for various cancers. Adenovirus type 5 injection which is the first oncolytic virus-drug named ‘ONCORINE’ was approved in 2005 for head and neck malignancy. A second one approved by the US FDA in October 2015, Talimogene laherparepvec (T-VEC), a genetically engineered herpes virus, that could treat advanced melanoma. More viruses are under trial for their oncolytic potential. In this article we intend to portray the various altered pathways developed, by which the tumour cells gain the trait to bring about increased viral tropism and tumour toxicity.

Keywords: Toxicity, Oncolytic Virus, Immunotherapy, Tumour Toxicity, Specificity