Evaluation of expression of the Wnt signaling components in canine mammary tumors by RT2 Profiler PCR Array and immunochemistry
Fang Yu1, Roberta Rasotto2, Hong Zhang1, Shimin Pei1, Bin Zhou1, Xu Yang1, Yipeng Jin1, Di Zhang1,*, Degui Lin1,*
1Department of Veterinary Clinical Science, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
2Clinical Pathology Department, Dick White Referrals, Cambridgeshire, CB8 0UH, UK
Correspondence to: Tel: +861062733621; Fax: +861062733621; E-mail: csama@sina.com (D Lin), dzhangdvm@cau.edu.cn (D Zhang)
Received: March 3, 2016; Revised: August 4, 2016; Accepted: August 26, 2016; Published online: September 1, 2016.
The Wnt signaling pathway and its key component β-catenin play critical roles in the development of diseases such as tumors in mammals. However, little is known about involvement of the Wnt/β-catenin signaling pathway in canine mammary tumors (CMTs). The present study detected the expression of 30 Wnt signaling pathway-related genes in CMTs, which are potentially useful for molecular diagnosis of CMTs and the development of new targeted therapies. Significant upregulation of DKK1, SFRP1, FZD3, β-catenin and LEF1 was detected in highly malignant CMTs compared to those in normal mammary gland tissues; while extremely significant upregulation of WNT5A was found in low malignant CMTs. Downregulation was only detected for SFRP4 in malignant CMT samples. The subcellular location of β-catenin and cyclin D1 in 100 CMT samples was also analyzed by immunohistochemistry. Significant increasing expression of β-catenin in the cytoplasm or cyclin D1 in nuclei was revealed. Additional Western blotting analysis revealed that the expression of β-catenin and LEF1 increased in major CMT samples tested. Taken together, these results provide important evidence for the activation status of the Wnt pathway in CMTs and valuable clues to the identifying biomarkers for the molecular diagnosis of CMT.
Keywords: RT2 Profiler PCR Array, Wnt signaling pathway, β-catenin, canine mammary tumor

© 2016 The Korean Society of Veterinary Science.