GIT-1 and Canine Mammary Gland Tumor - A Tissue Microarray Study (2005-2009)

Mammary gland tumors are among the most common tumors of the female dog. Recent studies have shown multiple risk factors and over-expressions of proteins that are highly associated with patient prognosis and overall survival. GIT-1 is a protein that appears to be associated with the regulation of cytoskeleton dynamics during cell spreading and migration. Recent evidence suggests that GIT-1 could be involved in human Huntington’s disease due to altered membrane trafficking. The role of GIT-1 over-expression in canine mammary gland tumor is currently unknown. However, through the microarray techniques adopted in this study, immunohistochemistry (IHC) significance of 90% was noted. Our goal is to identify the significance of GIT-1 IHC staining in canine mammary gland tumor and further connect these results with their clinical prognosis. 61 cases were collected through the years of 2005 to 2009. 58 dogs (95%) came up with a positive GIT-1 staining result. The dogs were grouped according to their IHC scores. The group with the higher IHC scores (≥3) reached an median survival of 361 days, whereas the lower IHC scoring group (≤2) had a median survival of 574 days, no significance was noted (p=0.94). The patient’s GIT1 significance were also compared with its WHO modified TNM staging scores, however still no significance was achieved (p=0.117). Nevertheless, we did manage to prove that the TNM staging system provided a rough understanding of the patient’s survival (p=0.015). We conclude that there was no significance noted between IHC scorings and patient prognosis.