Scientists find link between virus and genital cancer in horses
Human cervical cancer cases have shrunk thanks to development of efficient, yet cheap, vaccines. But what about research into animal genital cancer, and especially for horses? Little work in this specific area has been done over the years. However, new research from Austria and the UK shows that a novel papillomavirus plays a critical role in the development genital cancer in horses. This new evidence could lead to the development of a cure for Man's other best friend. The findings are presented in the Equine Veterinary Journal. The chances of genital cancer affecting horses are strong, particularly as the animals get older. While male horses are more affected by this disease than mares, both males and females can succumb to it. One of the underlying problems of this disease is that treatment is highly complex, thus triggering the animal's death. Since animal and human genital cancers are similar, researchers thought that a similar agent could be responsible for the disease. And studies have shown that a papillomavirus infection is behind a number of human genital cancers including cervical tumours. For the purposes of this study, the researchers from Austria's University of Veterinary Medicine, Vienna and the Rossdale Equine Hospital and Diagnostic Centre in Newmarket, UK used genetic techniques to identify papillomavirus DNA (deoxyribonucleic acid) in tissue samples from horses bearing genital squamous cell carcinomas (SCC). Dr Sabine Brandt, the head of the Equine Biotechnology Unit at the University of Veterinary Medicine and a co-author of the study, said the experiment had the feel of a 'magic bullet' but the team suspected a virus was the key component of this disease. And they were right. The scientists found a novel type of papillomavirus and called it 'Equus caballus papillomavirus-2 (EcPV-2). They discovered EcPV-2 DNA in all the genital SCC samples from affected horses in Austria and, independently, in almost all the samples from affected horses in the UK. The team did not detect the virus in any samples from horses free of tumours or any other type of cancer. They isolated and sequenced the entire genome of the EcPV-2, discovering that the novel virus is strongly related to the two viruses that are recognised for triggering most genital cancers in people. So the findings shed major light on how EcPV-2 could be the fundamental factor in causing disease in horses, especially genital cancer. According to the researchers, final proof would be needed to demonstrate that infecting mucous membranes with the virus leads to cancer development, and such tests have yet to be performed. More research is also needed to assess the frequency of the virus in horse populations, they said. However, the latest findings offer the medical world a good reason to try and prepare a vaccine. 'Identification of a papillomavirus causal for genital carcinomas in horses may lead to development of a vaccine that could be used to prevent this serious disease in horses,' the authors write. 'This would be analogous to man, where vaccination against oncogenic papillomavirus species is currently being used to help prevent cervical cancer.'
Countries
Austria, United Kingdom