Cancer catecholamine conundrum

Exercise, psychosocial stress, and drugs such as adrenergic agonists and antagonists increase the concentrations of catecholamines and/or alter adrenergic signaling. Intriguingly, exercise studies universally suggest that catecholamines are cancer-inhibiting whereas cancer stress studies typically report the opposite, whereas beta-blocker studies show variable effects. Here, we term variable effects of catecholamines in cancer the cancer catecholamine conundrum. Variable effects of catecholamines can potentially be explained by variable expression of nine adrenergic receptor isoforms and by other factors including catecholamine effects on cancer versus immune or endothelial cells. Future studies on catecholamines and cancer should seek to understand the mechanisms that explain variable effects of catecholamines in cancer to utilize beneficial or block detrimental effects of catecholamines in cancer patients.

Automated summary

This paragraph discusses the effects of exercise, psychosocial stress, and drugs on catecholamine concentrations and adrenergic signaling. While exercise studies suggest that catecholamines inhibit cancer, stress studies often report the opposite, and beta-blocker studies show varied effects. The variable effects may be due to the expression of different adrenergic receptor isoforms and the impact of catecholamines on cancer, immune, or endothelial cells. Future research should aim to understand the mechanisms behind these variable effects and utilize them for the benefit of cancer patients.