Vol. 11, Special Issue 6 (2022)

The present study was envisaged to investigate Ki-67 expression in canine mammary tissue and to correlate Ki-67 expression profile with that of different stages of metastasis in canine mammary tumors. Total RNA was isolated from twenty-six tissue samples (sixteen from tumor and ten from normal mammary tissue) using TRIzol. RNA concentration and quality were measured with a Nanodrop and by 2% agarose gel electrophoresis. First-strand cDNA was synthesized from total RNA using the Revert Aid H minus first strand cDNA synthesis kit. The generated cDNA was used as the template for quantitative real-time RT-PCR (qRT-PCR) to check the relative expression levels of Ki-67. HGPRT was used as an endogenous control. The relative gene expression levels were determined using the 2^-ΔΔCT method. The qPCR data on relative expression level of Ki-67 showed up regulation of 3.52 in Canine mammary tumor. The present study showed consistent up regulation of Ki-67 in all the samples compared suggesting a significant diagnostic role of Ki-67 in canine mammary tumors.