Dexmedetomidine promotes the progression of hepatocellular carcinoma through hepatic stellate cell activation

Abstract

Dexmedetomidine (DEX) is an anesthetic that is widely used in the clinic, and it has been reported to exhibit paradoxical effects in the progression of multiple solid tumors. In this study, we sought to explore the mechanism by which DEX regulates hepatocellular carcinoma (HCC) progression underlying liver fibrosis. We determined the effects of DEX on tumor progression in an orthotopic HCC mouse model of fibrotic liver. A coculture system and a subcutaneous xenograft model involving coimplantation of mouse hepatoma cells (H22) and primary activated hepatic stellate cells (aHSCs) were used to study the effects of DEX on HCC progression. We found that in the preclinical mouse model of liver fibrosis, DEX treatment significantly shortened median survival time and promoted tumor growth, intrahepatic metastasis and pulmonary metastasis. The DEX receptor (ADRA2A) was mainly expressed in aHSCs but was barely detected in HCC cells. DEX dramatically reinforced HCC malignant behaviors in the presence of aHSCs in both the coculture system and the coimplantation mouse model, but DEX alone exerted no significant effects on the malignancy of HCC. Mechanistically, DEX induced IL-6 secretion from aHSCs and promoted HCC progression via STAT3 activation. Our findings provide evidence that the clinical application of DEX may cause undesirable side effects in HCC patients with liver fibrosis.

Liver cancer: Common anesthetic can accelerate tumor progression

Researchers warn against using the anesthetic dexmedetomidine (DEX) in liver cancer patients after indications that it promotes tumor growth. Concerns have been raised that certain anesthetics, including DEX, can accelerate the progression of cancerous tumors, but the precise effects of DEX on liver cancer tumors are unclear. Most liver cancers develop in patients who already have fibrosis, a build-up of scarred tissue in the liver. This tissue accumulation stems from the activation of hepatic stellate cells (HSCs) during liver damage. Using human cancer cell lines and mouse models, Aimin Li and Xue Ning at the Southern Medical University, Guangzhou, China and co-workers demonstrated that DEX interacts with HSCs via a receptor protein on their cell surface, further enhancing activation levels. Activated HSCs in turn secrete factors that accelerate tumor growth and invasion.