Neuroendocrine modulation of cancer progression

Abstract

Clinical and animal studies now support the notion that psychological factors such as stress, chronic depression, and lack of social support might promote tumor growth and progression. Recently, cellular and molecular studies have started to identify biological processes that could mediate such effects. This review provides a mechanistic understanding of the relationship between biological and behavioral influences in cancer and points to more comprehensive behavioral and pharmacological approaches for better patient outcomes.

Figure 1

Effect of stress-associated factors on the tumor microenvironment. The stress response involves the central nervous system’s ability to perceive a threat. This response results in activation of the autonomic nervous system and the hypothalamic-pituitary-adrenal axis causing the release of catecholamines, glucocorticoids and other stress hormones from the adrenal gland, brain and sympathetic nerve terminals. These factors can alter the activity of various components of the tumor microenvironment. Effects include alteration of DNA repair mechanisms, enhanced tumor growth, increased cell migration and invasion, and stimulation of angiogenesis by increasing production of angiogenic factors. Collectively, these downstream effects result in the establishment of a favorable microenvironment that will support tumor initiation, growth and progression.