Leis-Filho Antonio Fernando, Lainetti Patricia deFaria, Kobayashi Priscila Emiko, Palmieri Chiara, Amorim Renée Laufer, Fonseca-Alves Carlos Eduardo
Department of Veterinary Surgery and Anesthesiology, School of Veterinary Medicine and Animal Science, São Paulo State University-UNESP, Botucatu, Sao Paulo, Brazil.
Department of Veterinary Clinic, School of Veterinary Medicine and Animal Science, São Paulo State University-UNESP, Botucatu, Sao Paulo, Brazil.
Prostate. 2021 Oct;81(14):1021-1031. doi: 10.1002/pros.24199. Epub 2021 Jul 28.
Vascular endothelial growth factor-A (VEGF-A) and its receptor, VEGF receptor-2 (VEGFR-2), represent a complex family of angiogenic molecules consisting of different ligands and receptors. Due to the importance of VEGF-A/VEGFR-2 signaling in tumor proliferation and angiogenesis, this study aimed to evaluate the protein and gene expression levels of VEGF-A and VEGFR-2 in canine prostate cancer (PC).
We analyzed VEGF-A and VEGFR-2 expression in 87 PC samples by immunohistochemistry and quantitative-polymerase chain reaction. PC samples were graded according to the Gleason score and the immunohistochemical staining for VEGF-A and VEGFR-2 was quantified using a selected threshold from the ImageJ Software. Microvascular density was assessed by cluster of differentiation 31 staining and counting the number of positive vessels. Additionally, the homology of VEGF-A and VEGFR-2 between humans and dogs was assessed, followed by the construction of a protein structure homology model to compare the tertiary structures of these proteins in both species.
Negative to weakly positive expression levels of VEGF-A and VEGFR-2 were observed in the epithelial cells of the normal prostate (NP) and prostatic hyperplasia samples. In contrast, the canine proliferative atrophy and PC samples exhibited higher VEGF-A (p < .0001) and VEGFR-2 (p < .0001) compared to NP. Moreover, positive correlations between the expression levels of VEGF-A and VEGFR-2 (Spearman's coefficient (r) = .68, p = .013) and the expression levels of VEGF-A and VEGFR-2 proteins (r = .8, p < .0001) were also observed in the NP samples. Additionally, the patients with PC exhibiting higher VEGFR-2 expression levels experienced a shorter survival period (p = .0372). Furthermore, we found an association between the microvascular density and overall survival. Dogs with a higher number of vessels showed a shorter survival time. We further demonstrated that the VEGF-A and VEGFR-2 exhibited high homology between humans and dogs, and identified their protein structures in both species.
In conclusion, VEGFR-2 appears to be an independent prognostic factor in animals with PC. VEGF-A and VEGFR-2 are highly conserved between humans and dogs, which can be investigated further in future cross-species studies to explore their therapeutic applications.
血管内皮生长因子 -A(VEGF-A)及其受体血管内皮生长因子受体 -2(VEGFR-2)代表了一个由不同配体和受体组成的复杂血管生成分子家族。鉴于VEGF-A/VEGFR-2信号在肿瘤增殖和血管生成中的重要性,本研究旨在评估犬前列腺癌(PC)中VEGF-A和VEGFR-2的蛋白质和基因表达水平。
我们通过免疫组织化学和定量聚合酶链反应分析了87份PC样本中VEGF-A和VEGFR-2的表达。PC样本根据Gleason评分进行分级,并使用ImageJ软件选择的阈值对VEGF-A和VEGFR-2的免疫组织化学染色进行定量。通过分化簇31染色和计数阳性血管数量来评估微血管密度。此外,评估了人和犬之间VEGF-A和VEGFR-2的同源性,随后构建蛋白质结构同源性模型以比较这两种物种中这些蛋白质的三级结构。
在正常前列腺(NP)和前列腺增生样本的上皮细胞中观察到VEGF-A和VEGFR-2呈阴性至弱阳性表达水平。相比之下,犬增殖性萎缩和PC样本与NP相比,VEGF-A(p <.0001)和VEGFR-2(p <.0001)表达更高。此外,在NP样本中还观察到VEGF-A和VEGFR-2的表达水平之间(Spearman系数(r)=.68,p =.013)以及VEGF-A和VEGFR-2蛋白的表达水平之间(r =.8,p <.0001)呈正相关。此外,VEGFR-2表达水平较高的PC患者生存期较短(p =.0372)。此外,我们发现微血管密度与总生存期之间存在关联。血管数量较多的犬生存时间较短。我们进一步证明VEGF-A和VEGFR-2在人和犬之间表现出高度同源性,并确定了这两种物种中的蛋白质结构。
总之,VEGFR-2似乎是患有PC的动物的一个独立预后因素。VEGF-A和VEGFR-2在人和犬之间高度保守,这可以在未来的跨物种研究中进一步研究以探索它们的治疗应用。