Monitoring Cellular Immune Responses in Cancer Therapy

Cytokines are probably the most important biologically active group of molecules to be identified since the discovery of the classical endocrine hormones. Progress with the identification of new cytokine molecules is particularly fast approaching and now it is evident that cytokines are involved, at least to some extent, in most if not all physiological processes. According to the National Cancer Institute, USA, "Cancer" is a term used for sicknesses in which atypical cells divide without manage and are capable of invading different cells. Cancer is typically characterized as a heightened proliferation of cells. Cancer arises from the dysfunction of many critical cell checkpoints. By utilizing the knowledge of unique or overexpressed cell-surface antigens or receptors on tumour cells as targets, a new form of cancer therapy has evolved over the last two decades. In particular, a variety of receptors for cellular growth factors and cytokines are overexpressed on tumour cells, which may serve as targets for cancer therapy. Previous studies reported that neutralizing monoclonal antibodies either alone or attached with radionuclide or antisense oligonucleotides to some of these receptors can selectively inhibit the growth of tumour cells by evoking host immune responses. For direct tumour cell killing, antibodies or ligands have been chemically conjugated or genetically fused to plant or bacterial toxins. Current medicinal treatments for cancer, including chemotherapy consider cytokine therapy as adjuvant therapy. Being a novel therapeutic approach, cytokine therapy has proved successful in treating patients having advanced malignancies. It manipulates the immune response generating immune effector cells for eradicating solid tumours. Only after the conventional therapies like chemotherapy, surgery etc having been performed is cytokine therapy administered. Clinical trials have already been performed for the administration of TNF-alpha, INF-alpha, IL-2, IL-12. Some clinical trials have given positive results in the form of partial or complete tumour regression. This has raised hope for selecting a suitable cytokine or its combination, its dose level for treating advanced malignancies.