Abstract：
Cutaneous squamous cell carcinoma (cSCC) is a neoplasm type often diagnosed in dogs. However, studies focused on further investigating its molecular biology, mainly biomarkers to help implementing new therapies, remain scare in the literature. Thus, immunostaining and the gene expression of epidermal growth factor receptors (HER1 and HER2) in canine cSCC presenting different cell differentiation degrees were herein assessed. Thirty-two (32) canine cSCC were selected, classified based on to their cell differentiation degree and subjected to immunohistochemical study to assess HER1 and HER2 immunostaining intensity and distribution. In addition, HER1 and HER2 gene expression was investigated through real-time PCR. Membranous and cytoplasmic immunostaining were observed in both markers. HER2 prevailed in poorly differentiated cSCC; there was positive protein expression correlation between both markers. Mean HER1 gene expression was higher in moderately differentiated, whereas mean HER2 gene expression was higher in poorly differentiated cSCC. Moreover, there was gene expression correlation between markers, regardless of cell differentiation degree. Thus, HER2 protein immunostaining and gene expression were higher in poorly differentiated canine cSCC and it enabled understanding that increase observed in this epidermal growth factor receptor is proportional to this neoplasm\'s cell differentiation degree in canine species. Results in the current study helped better understanding canine cSCC\'s molecular biology; however, it is relevant studying other markers aiming to investigate signaling pathways.
摘要：
皮肤鳞状细胞癌（cSCC）是一种经常在狗中诊断的肿瘤类型。然而,研究集中在进一步研究其分子生物学，主要是帮助实施新疗法的生物标志物，仍然是文学中的恐慌。因此，本文评估了呈现不同细胞分化程度的犬cSCC中的免疫染色和表皮生长因子受体（HER1和HER2）的基因表达。选择了32（32）只犬cSCC，根据其细胞分化程度进行分类，并进行免疫组织化学研究以评估HER1和HER2免疫染色的强度和分布。此外,通过实时PCR研究HER1和HER2基因表达。在两种标记中均观察到膜和细胞质免疫染色。HER2在低分化的cSCC中普遍存在；两种标志物之间存在正蛋白表达相关性。平均HER1基因表达在中等分化中更高，而低分化cSCC中平均HER2基因表达较高。此外，标记之间存在基因表达相关性，无论细胞分化程度。因此，低分化犬cSCC中HER2蛋白免疫染色和基因表达较高，并且能够理解在这种表皮生长因子受体中观察到的增加与犬物种中这种肿瘤的细胞分化程度成正比。本研究的结果有助于更好地理解犬cSCC的分子生物学；然而，它是相关的研究其他标记，旨在研究信号通路。
