Evaluation of Estrogen Receptor α and Genes Expression in Normal and Neoplastic Mammary Gland in Dogs by Real-time PCR

Background: Estrogen and progesterone play a key role in mammary tumorigenesis of female dogs. Malignant tumors are considered hormone-dependent neoplasms, which may reappear after surgical removal or might spread to other organs such as liver, lymph nodes, and lungs. Objective: The purpose of this study was to evaluate the expression of estrogen receptor α and genes in normal and neoplastic mammary glands of female dogs. Methods: Ten neoplastic tumors (benign and malignant) and 10 normal samples were selected. After RNA extraction and cDNA synthesis, ERα and ERβ genes were amplified by Real-time PCR based on SYBR green related to β-actin reference gene. Results: The obtained Ct and ΔCt values were analyzed by GLM procedure of SAS software v9.2. The results showed that the expression of ERα and ERβ genes in neoplastic cases was over- and down-expressed respectively as compared with normal samples (p < 0.01). Conclusion: The findings indicated that these genes could be used as reference genes for screening and also for early diagnosis of patients, and this method could be helpful for patient selection and monitoring of the anti-estrogen therapy.