Sykora S, Jindra C, Hofer M, Steinborn R, Brandt S
Research Group Oncology, Equine Clinic, University of Veterinary Medicine, Veterinaerplatz 1, 1210 Vienna, Austria.
Genomics Core Facility, VetCore, University of Veterinary Medicine, Veterinaerplatz 1, 1210 Vienna, Austria.
Vet J. 2017 Jul;225:3-8. doi: 10.1016/j.tvjl.2017.04.014. Epub 2017 May 3.
In horses, squamous cell carcinomas (SCC) commonly affect the external genitals. There is growing evidence that equine papillomavirus type 2 (EcPV2) infection promotes disease development. To assess the possible association of EcPV2 with equine SCCs of the head (HSCC), 15 HSCC DNA samples were screened by E6/E7, E2, and LCR PCR and amplicons were analysed for sequence variations. The physical form of EcPV2 in HSCC, genital lesions, and smegma from horses with SCC was then addressed using EcPV2 immunocapture PCR (IC/PCR) for detection of virion, and E6 vs. E2 qPCR to investigate possible integration events. Four of 15 HSCC tested positive for EcPV2 DNA and harboured known or novel genetic variants of E6, E7, E2 and the LCR. Eighteen of 35 sample extracts including 3/4 smegma samples scored positive by IC/PCR, suggesting that about 51% of tested extracts harboured virions. E6/E2 qPCR from tumour DNA revealed E2/E6 copies/cell ranging between <1 (E2; E6) and 797 (E2) or 1434 (E6). IC/PCR-positive smegma samples contained higher E2 and E6 copy numbers, ranging between 1490 and 4.95×10 (E2) or 2227 and 8.54×10 (E6) copies/cell. Together with IC/PCR results, this finding suggests that smegma can serve as a rich EcPV2 reservoir. HSCCs harboured significantly lower viral DNA amounts (<1-25 copies/cell) than most genital tumour and smegma DNA isolates. The majority of samples contained more E6 than E2 DNA, with E6:E2 ratios ranging between 0.88 and 4.12. Although not statistically significant (P>0.05), this finding suggests that EcPV2 can integrate into the equine host cell genome.
在马中，鳞状细胞癌（SCC）通常影响外生殖器。越来越多的证据表明，2型马乳头瘤病毒（EcPV2）感染促进疾病发展。为了评估EcPV2与马头部鳞状细胞癌（HSCC）的可能关联，通过E6/E7、E2和LCR PCR对15份HSCC DNA样本进行筛选，并对扩增子进行序列变异分析。然后，使用EcPV2免疫捕获PCR（IC/PCR）检测病毒粒子，并用E6与E2定量PCR研究可能的整合事件，以探讨HSCC、生殖器病变以及患有SCC的马的包皮垢中EcPV2的物理形式。15份HSCC样本中有4份EcPV2 DNA检测呈阳性，并含有E6、E7、E2和LCR的已知或新的基因变异。35份样本提取物中有18份，包括3/4的包皮垢样本，IC/PCR检测呈阳性，这表明约51%的检测提取物含有病毒粒子。肿瘤DNA的E6/E2定量PCR显示，每个细胞的E2/E6拷贝数在<1（E2；E6）至797（E2）或1434（E6）之间。IC/PCR阳性的包皮垢样本含有更高的E2和E6拷贝数，每个细胞的拷贝数在1490至4.95×10（E2）或2227至8.54×10（E6）之间。结合IC/PCR结果，这一发现表明包皮垢可作为丰富的EcPV2储存库。与大多数生殖器肿瘤和包皮垢DNA分离物相比，HSCC中病毒DNA含量显著更低（<1 - 25拷贝/细胞）。大多数样本中E6 DNA比E2 DNA更多，E6:E2比值在0.88至4.12之间。尽管这一发现无统计学意义（P>0.05），但表明EcPV2可整合到马宿主细胞基因组中。
