The role of immunotherapy in cancer treatment

Abstract

Cancer is a genetic disease with the growth of tumor cells initiated and promoted by mutations in a group of genes known as drivers. This is just the beginning of the process of cancerogenesis, characterized by cellular, genetic and epigenetic alterations as well as the loss of normal cellular regulatory processes. The revelation of complexity of mechanisms underlying the Cancer-Immunity Cycle has resulted in defining immunological and histological profiles responsible for suppressing or promoting anticancer immunity. It has been observed that such profile is determined not only by intrinsic tumor properties, patients’ genetics, but also such extrinsic elements as gut microbiota, the presence of infection or exposure to sunlight. The balance between these factors, known as a cancer-immune set point, is a threshold that must be exceeded for a patient to respond to immunotherapy. Among various types of cancer immunotherapy, we can distinguish an adoptive T cell transfer, checkpoint blockade and neoantigen vaccines. The genuine features of human immune system, such as specific recognition and elimination of cancer cells, adaptation to an evolving tumor and immunological memory seem to be a perfect combination to create a powerful weapon for long-term cancer control. Nevertheless, the exact understanding of immunological mechanisms in both tumor growth and cancer elimination requires more thorough studies and may lead to enhancing the efficiency of a wide variety of immunotherapeutic anticancer approaches.