The ambiguity of opioids revealed by Immunology is changing the knowledge and the therapeutic approach in cancer and non-cancer pain: A narrative review.

The ambiguity of opioids revealed by Immunology is changing the knowledge and the therapeutic approach in cancer and non-cancer pain: A narrative review. Immunol Lett. 2020 Jun 23;: Authors: Santoni A, Arcuri E Abstract Herein, we summarize the steps of a common scientific path taken by the two Guest Editors, an Anesthesiologist (EA) and an Immunologist (AS), and started 25 years ago at the National Cancer Institute in Rome. When in 1980 WHO codified the usage of opioids for cancer pain relief, it was matter of debate whether only disease progression rather than opioid tolerance were the driving force of opioid escalation. The selective intratumoral accumulation of morphine observed in an experimental xenograft model - the initial scenario of our scientific collaboration - revealed a surprising interaction between the opioid and the opioid receptors expressed by cells of tumor microenvironment. This link could explain the peculiar opioid tolerance and likely hyperalgesia that were observed in the emerging clinical experience of cancer paradoxical pain and suggestive of opioid ambiguity. More elegant cancer pain experimental models, in particular of bone cancer demonstrated the relevance of inflammatory mediators produced and released by tumor microenvironment cells. These factors were the words of an immune-mediated cross-talk between the tumor and the peripheral and central nervous systems leading to neuroinflammation and consequent...
Source: Immunology Letters - Category: Allergy & Immunology Authors: Tags: Immunol Lett Source Type: research