Devil vaccine a step closer

Greg Woods and Bruce Lyons.

Greg Woods and Bruce Lyons.

The results of an international study published recently in Scientific Reports has confirmed the fatal facial tumour disease that has decimated populations of Tasmanian devils in the wild for over 20 years, can be cured using immunotherapy.

Led by the University of Tasmania’s Menzies Institute for Medical Research, the study involved scientists from the Universities of Sydney, Southampton, Southern Denmark and Cambridge, as well as those from UTAS’s School of Medicine, the Walter and Eliza Hall Institute of Medical Research, and CSL Ltd.

The aim of the study was to ‘explore immunisation protocols to enhance protective responses against DFTD’, but due to devils’ endangered status, only a limited number of animals are available for research purposes. This five-year trial, that tested four immunisation protocols sequentially, was therefore restricted to nine healthy and genetically different animals, some of which had reached an advanced age. Continue reading Devil vaccine a step closer

Early canine cancer succes

IMG_1169A University of Queensland trial of a new injectable treatment for canine cancer has shown early results in slowing down and ultimately reversing the growth of a tumour.

UQ PhD candidate and veterinarian Moira Brennan said the vaccine was in the early stages of testing and had apparently worked for its first patient, a dog with an inoperable terminal mast cell tumour.

The treatment, which stimulates an immune response in the tumour, has been tolerated exceedingly well in the first dog trialled – a rottweiler named Jackson,” Brennan said.

We were pleased that Jackson’s tumour, which had failed to respond to traditional chemotherapy, appears to have disappeared as a result of this experimental treatment.”

The long-term effects of the treatment are unknown, and Brennan is recruiting other dogs with untreatable mast cell tumour or malignant melanoma to join this trial. Continue reading Early canine cancer succes

Transmissible cancers in dogs and Tasmanian devils

Figure 1.

The Tasmanian devil, the world’s largest marsupial carnivore, is facing possible extinction in the wild due to a transmissible facial cancer known as Tasmanian devil facial tumour disease (DFTD) (Figure 1). DFTD is spread when living cancer cells are spread between animals by biting. In DFTD, the living cancer cell itself is the infectious agent of disease and it remains unclear why these cancer cells are not detected and rejected by the devil’s immune system. The distressing plight of the Tasmanian devil has drawn attention to the existence of transmissible cancers, parasitic cancers spread by the transfer of living cancer cells between hosts. However, it remains a surprisingly little-known fact that the only other transmissible cancer that bears any resemblance to DFTD is a dog cancer that is right under our noses here in Australia.

Canine transmissible venereal tumour (CTVT) is one of the world’s most remarkable cancers. It is a transmissible cancer that affects dogs worldwide. Usually spread during coitus, the disease is most prevalent in areas with large numbers of free-roaming sexually active dogs. The tumour affects both male and female animals, and appears to affect dogs of any breed. CTVT generally manifests itself in the appearance of tumours in and around the genital area, often at the base of the penis in males and in the vulva of females. Starting as small shiny pink/grey lesions, the tumours can progress to become very large and multi-lobulated (Figure 2). The tumour may aggressively invade surrounding tissues and become ulcerated and secondarily infected. However, a combination of surgical debulking and chemotherapy (using vincristine) is often curative.

Figure 2

Genetic studies have provided strong evidence that CTVT is in fact one living cancer cell line that has spread worldwide with dogs. Thus all CTVT tumours are derived from a single original tumour that arose once and has been transmitted through the dog population as a clone. The tumour itself bears closest genetic resemblance to wolves, suggesting that this tumour may have first arisen in a wolf before hitch-hiking its way into dogs through sexual contact. Genetic evidence suggests that the tumour may in fact be quite old, and that the original wolf that gave rise to the tumour may have even lived thousands of years ago. CTVT is by far the oldest known continuously growing cancer in the world. Continue reading Transmissible cancers in dogs and Tasmanian devils