The mechanistic target of rapamycin (mTOR) plays an important role in cellular functions, including growth and metabolism. Recently, mTOR and the activated phosphorylated form of mTOR (p-mTOR) have been reported as potential prognostic markers in many human tumours. However, there are few studies on its activation in canine tumours. We investigated the expression of p-mTOR in 17 canine skin tumours (CSTs), of which 58.8% were epithelial and melanocytic and 41.2% were mesenchymal tumours. Seventy-six per cent of the CSTs had high or moderate expression of p-mTOR. Mean p-mTOR expression in the epithelial and melanocytic tumours (5.7 ± 0.56) was significantly higher (P <0.05) than that of the mesenchymal tumours (3.14 ± 0.55). The age of the animals had no influence on p-mTOR expression. These findings suggest that activation of m-TOR is important in the development of skin tumours in dogs and the study might form the basis for further research on utilizing m-TOR inhibitors as improved therapeutic modalities in canine skin tumours.

雷帕霉素的机械靶点 (mTOR) 在细胞功能（包括生长和代谢）中起着重要作用。最近，mTOR 和 mTOR 的活化磷酸化形式 (p-mTOR) 已被报道为许多人类肿瘤中的潜在预后标志物。然而，关于它在犬肿瘤中的激活的研究很少。我们研究了 p-mTOR 在 17 个犬皮肤肿瘤 (CST) 中的表达，其中 58.8% 是上皮和黑素细胞肿瘤，41.2% 是间充质肿瘤。76% 的 CST 具有高或中度 p-mTOR 表达。上皮和黑素细胞肿瘤中 p-mTOR 的平均表达 (5.7 ± 0.56) 显着更高（P <0.05) 比间充质肿瘤 (3.14 ± 0.55)。动物的年龄对 p-mTOR 表达没有影响。这些发现表明 m-TOR 的激活在狗皮肤肿瘤的发展中很重要，该研究可能为进一步研究利用 m-TOR 抑制剂作为犬皮肤肿瘤的改进治疗方式奠定基础。