IL-6 and IL-8 levels in dog mammary gland tumors and their importance

Abstract

Mammary gland tumors are the most common malignant diseases which seriously threaten the health of women and female dogs. There is a lack of an effective tumor marker which can effectively assist in the early diagnosis, and prognosis of mammary gland tumors in veterinary clinical medicine. IL-6, and IL-8 as immunosuppressive factors may stimulate tumor cells growth, contribute to loco-regional relapse and metastasis that might be utilized as a marker for immunity status and monitoring of the course of tumor. The present study aimed to investigate the expression of serum/tissue IL-6, IL-8 and IL-10 in canine mammary gland tumors using Enzyme linked immunosorbent assay(ELISA), Western blot and Immunohistochemistry assay(IHC) to determine whether it is associated with tumor progression. The results showed that levels of IL-6, IL-8 and IL-10 in serum were higher in malignant tumor group than that in benign tumor and control group; the expression levels of IL-6 and IL-8 were significantly elevated in grade III than in grade I and II and was related to metastasis. Likewise, IL-6 and IL-8 were also highly expressed in malignant tumor tissues. Elevated expression of IL-6 was associated with histopathological grade and metastases in malignant tumors. Moreover, high expression of IL-6 occurred in the Basal-like subtypes whereas high expression of IL-8 occurred in the Luminal B subtypes. The results of this study indicated that changes of IL-6 and IL-8 in the tumor microenvironments were closely related to the diseases status and may be used as a potential diagnostic or biomarker in canine mammary gland tumors.