Canine: a genomic model for human breast cancer
There are many diseases that are common to dog and man. cDNA arrays constitute one of the most powerful tools for studying gene expression in many different organisms. Access to cancerous tissue is critical in order to know its regulation. This study was using cDNA array in cross-species hybridization with canine breast cancer RNA. Fragments of normal and cancerous tissues were obtained from canine mammary glands after routine mastectomy surgery .The tissues were dissected and small pieces were quickly frozen in liquid nitrogen and stored frozen at - 80°C.Total RNA was isolated by phenol-chloroform extraction (TRIzol ®, GibcoBRL). The cDNA synthesis was done by using reverse transcriptase reaction. Nylon membranes were hybridized to the labeled probe and after 24 hours of exposure images were digitalized. Scanned images were visually and analyzed. Results showed a set of 222 up-regulated genes (p < 0.01). Among all samples some genes were expressed in all cancerous tissue when compared with normal tissue. These genes were: ESR2, PGR, RL23, CCL3, MYL3, NME1, RPS9, RPS11, RPS23, SLC25A5, HDAC2, HSPE1, CDC45, ESRRB, ATP5J2, NUTF2, FOSB, TSK, FHL5MG, C4767, IGF1 and RHSPA5. Many thousands of canine breast cancer components and candidate molecular markers can now be studied and compared with human breast cancer using human microarray technologies.Acknowledgements : This work was supported by Fundação de Amparo À Pesquisa do Estado de São Paulo (FAPESP) – Brasil an Waltham Foundation.