Oxytocin and cancer: An emerging link

Abstract

The neuropeptide hormone oxytocin, which is released from the posterior pituitary gland, is involved in a number of physiological processes. Understanding of its effects is gradually increasing due to new research in this area. While mostly recognized as a reproductive system hormone, oxytocin also regulates other organ systems such as the brain and cardiovascular system. Recently, research has focused on unraveling its involvement in cancer, and emerging evidence suggests a potential role for oxytocin as a cancer biomarker. This review summarizes observations linking oxytocin and cancer, with a special emphasis on prostate cancer, where it may promote cell proliferation. Research suggests that oxytocin effects may depend on cell type, concentration of the hormone, its interactions with other hormones in the microenvironment, and the precise localization of its receptor on the cell membrane. Future research is needed to further elucidate the involvement of oxytocin in cancer, and whether it could be a clinical cancer biomarker or therapeutic target.

Keywords: Cancer; Exercise; Oxytocin; Pancreas; Prostate.

Figure 1

The potential role of oxytocin in various cancers and cell types. Bold font indicates conflicting observations.

Figure 2

Mechanisms of action of oxytocin. Yellow and purple are anti-proliferation (via different subunits), red is proliferation, and blue is smooth muscle contraction. Gαi: Guanine nucleotide binding protein subunit alpha I; Gαs: Guanine nucleotide binding protein subunit alpha s; Gαq: Guanine nucleotide binding protein subunit alpha q; PI3K: Phosphoinositide 3-kinase; PLCβ: Phospholipase beta; Src: Tyrosine protein kinase; ERK: Extracellular signal-regulated kinase; p21: Cyclin-dependent kinase inhibitor 1; ADCY: Adenylate cyclase; cAMP: Cyclic AMP; PKA: Protein kinase A; DAG: Diacylglycerol; PKC: Protein kinase C; Insp3: Inositol triphosphate 3; MLCK: Myosin light chain kinase.