Endocannabinoid-metabolizing enzymes in tumors helped colon cancer evade the immune system in mice

CYP4X1 and sEH enzymes metabolize endocannabinoids to produce 14,15-EET-EA, which acts on GPR119 receptors in cancer-associated fibroblasts. This upregulates PD-L1, CXCL12, and TGF-beta, promoting regulatory T cell infiltration and impairing CD8+ T cell function. Blocking the CYP4X1/sEH-GPR119 axis enhanced anti-PD-1 immunotherapy efficacy in mice.

Preclinical study using mouse colon cancer models and human colon cancer tissue analysis. Investigated the CYP4X1/sEH pathway for endocannabinoid metabolism, identified the 14,15-EET-EA metabolite and its receptor GPR119, and tested pathway inhibition combined with anti-PD-1 therapy.

Immunotherapy has transformed cancer treatment but only works in a fraction of patients. This research identifies a specific endocannabinoid metabolism pathway that tumors exploit to evade immune attack, offering a potential new drug target to make immunotherapy more effective.

The endocannabinoid system is increasingly recognized as playing roles far beyond mood and pain. This study reveals it as a key player in how tumors manipulate their microenvironment to survive, opening up entirely new strategies for combination immunotherapy.

Mouse models do not always translate to human outcomes. The pathway was studied primarily in colon cancer; relevance to other cancers is unknown. No clinical trials yet. Complexity of the signaling pathway may make therapeutic targeting challenging.