Circulating Endocannabinoids in Canine Cutaneous Mast Cell Tumor

Area of Science:

• Veterinary Oncology
• Biochemistry
• Canine Health

Background:

• Cutaneous mast cell tumors (cMCT) are common in dogs.
• The endocannabinoid system (ECS), involving endocannabinoids (eCBs), plays a role in various physiological processes.
• Alterations in eCBs may be linked to tumor development.

Purpose of the Study:

• To investigate plasma levels of key endocannabinoids (AEA, 2-AG, PEA, OEA) in dogs with cMCT.
• To determine if eCBs can serve as biomarkers for distinguishing cMCT in dogs.
• To explore the relationship between eCB levels and cMCT presence.

Main Methods:

• Plasma samples were collected from 17 dogs with cMCT and 11 healthy control dogs.
• Levels of four endocannabinoids (AEA, 2-AG, PEA, OEA) were quantified using established analytical techniques.
• Receiver Operating Characteristic (ROC) curve analysis was used to assess the diagnostic accuracy of eCBs.

Main Results:

• Dogs with cMCT exhibited significantly higher plasma 2-AG levels (p=0.0001) compared to controls.
• Lower plasma levels of AEA (p=0.0012) and PEA (p=0.0075) were observed in dogs with cMCT.
• 2-AG demonstrated high diagnostic accuracy (0.98 AUC) for distinguishing cMCT, with 94% sensitivity and 90% specificity at a threshold of 52.75 pmol/mL.

Conclusions:

• This study is the first to report altered plasma eCB levels in dogs with cMCT.
• Plasmatic 2-AG, AEA, and PEA show potential as non-invasive biomarkers for cMCT diagnosis in dogs.
• Further research is warranted to elucidate the role of eCBs in canine tumorigenesis.