Assessing the Interleukin 35 Immunoexpression in Malignant Canine Mammary Tumors: Association With Clinicopathological Parameters and Prognosis.

Abstract

BACKGROUND/AIM: IL-35 has a prominent immunosuppressive role and its overexpression has been reported in human breast cancer. However, the impact of IL-35 in canine mammary carcinogenesis has not been addressed yet. The present study determined the clinicopathological significance of IL-35 immunoexpression and its correlation with overall survival (OS) in 72 malignant canine mammary tumor (CMT) patients. MATERIALS AND METHODS: Formalin-fixed paraffin-embedded malignant CMT samples (n=72) were submitted to immunohistochemical staining to detect IL-35 expression. Survival curves were obtained by the Kaplan-Meier method and the log-rank test was used for the survival estimates. Cox proportional hazard model for multivariate analysis was also performed. RESULTS: IL-35 overexpression was associated with: skin ulceration, tumor necrosis, mitotic index, nuclear pleomorphism, tumor differentiation, histological grade of malignancy (HGM), neoplastic intravascular emboli and lymph node metastasis. Additionally, IL-35 was also correlated with a worse overall survival in multivariate analysis, arising as an independent predictor of poor prognosis. CONCLUSION: IL-35 is associated with carcinogenesis and worse prognosis of CMT.