The multifaceted value of antidepressants in cancer therapeutics

Abstract

Prostaglandins are ephemeral, infinitesimal lipid signalers self-regulating every cell in the body, including those subserving mood and immunity. At first, prostaglandins were perceived as master switches, but are now believed to regulate every component of cellular microanatomy and physiology, including those of the organelles, cytoskeleton, proteins, enzymes and nucleic acids. They signal cell-to-cell, tissue-totissue, organ-to-organ, brain-to-body, body-to-brain, and body as a whole and differentiate between function and dysfunction of every cell. Prostaglandins regulate the synthesis, inhibition and expression of genes, and the growth, differentiation and replication of cells. Amongst the mechanisms of carcinogenesis are up-regulation of cyclooxygenase, oncogene synthesis and expression, viral activation, signal disruption, accelerated cell replication, failed apoptosis, tumour initiation and promotion, angiogenesis, metastasis, immunosuppression and autoimmunity. All fall within the orbit of prostaglandins and their forming and degrading enzymes. Isolation of such isoforms of cyclooxygenase as COX-2, and the synthesis of selective COX-2 inhibitors has stimulated research into the expression of this isoform in cancer and its role in apoptosis. COX-2 is up regulated in many cancers. In a population study, aspirin may have reduced the risk of colon cancer by 40%. When synthesised excessively, prostaglandin E2 depresses cellular and humoral immunity, allowing pathogens to repli-