Cytokines such as interleukin-2 (IL-2), interferon (IFN), and tumour necrosis factor (TNF) have been used with varying success in the treatment of cancer, due to their immunostimulatory effect.
Interferons were the first cytokine to be studied.9 The interferons have a number of activities such as:10
- inhibition of angiogenesis
- regulation of differentiation
- anti-tumour effects.
They have been used in cancer therapy in a variety of doses and schedules. Interferons can be divided into two types:11
- Type I (IFN-α and IFN-β) binds to the cell surface receptor of effector cells
- Type II (IFN-γ) binds to different cell surface receptors.
Interleukins are cytokines that send signals primarily between lymphocytes. They have also been found to have broader activities such as coordinating various immune cell activities and other organ systems to mount a multi-level defense.9 They do not act independently but are messengers to initiate, coordinate, and sometimes augment potent immune defense activities.9
There are several interleukins that have been discovered and they are identified by a number. Currently there is only one interleukin, IL-2, that has been used as an anticancer therapy at varying doses and schedules.
There are two types of TNF:12
- TNF-α (cachectin) actions include increased catabolism, enhanced phagocytosis, and tumour destruction
- TNF-β (lymphotoxin) actions include cell killing and direct tumouricidal capability.
Colony stimulating factors (CSF) or haematopoietic growth factors (HGF) are naturally occurring proteins or cytokines that regulate proliferation, differentiation, and maturation of all blood cell lines.13 Recombinant DNA technology has permitted the manufacture of large quantities of these substances.
Some HGF stimulate the growth of multiple blood cell lines such as granulocyte-macrophage CSF (GM-CSF). Others stimulate production of a single cell line.13
Single cell line CSF includes:
- granulocyte-CSF (G-CSF)
- erythropoietin (EPO)
- thrombopoietin (TPO).
Recombinant versions are used as supportive therapy and can prevent or minimise the myelosuppressive effects of cancer control efforts.13
Identify a cytokine used in cancer control and describe the:
- mechanism of action
- indications for its use in clinical practice
- nursing care considerations associated with use of this agent.