The sexually transmitted dog cancer that could tell us how tumours develop

The mutations of canine transmissible venereal tumour (CTVT) promises to show how the tumours develop and respond to environmental pressures.

Not even Lassie could have seen this coming. As you contemplate the bleakest bits of the cancer report issued by the World Health Organisation on 3 February, take heart: recent research suggests that the genitals of the world’s dogs might offer clues for fighting the war on cancer.

Cancer is mainly a disease of longevity, and as the global population grows and ages, the incidence of cancer is on the rise. As the World Cancer Report puts it, “The worldwide burden of cancer remains huge and is escalating.” There is no quick fix: advanced cancers, or those that have metastasised, are “mostly intransigent to treatment”, and encouraging a healthy diet is likely to have only “modest” effects. “Billions of dollars,” the report argues, “are riding on the premise that personalised medicine and targeted therapy will come to the rescue.”

As luck would have it, newly published research offers an 11,000-year-old Spitz as a rescue dog. It was a fair size, with a mostly black coat and a face not dissimilar to today’s Spitz dogs. Its genes were a mixture of wolf and more modern canines. We know all this because a tumour grew in the dog’s body. It’s the same tumour that is infecting dogs all over the world today, and its genome offers clues to how tumours take over the body – and why sometimes they don’t.

Genetic scientists report that the canine transmissible venereal tumour (CTVT), found in dogs all around the world, is the same organism that first came into existence in that unlucky dog 11,000 years ago. Researchers at the Wellcome Trust Sanger Institute in Cambridgeshire documented its genome and published the results in the journal Science.

CTVT is one of only two naturally occurring transmissible tumours; the other one grows on the face of the Tasmanian devil. CTVT is transmitted through mating and other activities that allow cells to slough off one dog and embed in the tissues of another. This is probably not the bit to dwell on (look on the internet for images of CTVT and you’ll agree). What is interesting is that the tumour has modified significantly over the millennia.

Examining these mutations – and comparing them with the mutations that are slowly wiping out the Tasmanian devil – promises to show how the tumours develop and respond to environmental pressures. It seems that the ability of genetically diverse dogs to interbreed has rendered CTVT relatively harmless, by creating the conditions that force its mutations in certain directions and minimise the proliferation of truly dangerous forms. The Tasmanian devil, on the other hand, lives in relative isolation, genetically speaking. Its facial tumour hasn’t been forced to adapt, and it is quickly wiping out the host species.

The mutations of the canine tumour do more than alter how fast its cells replicate. They also allow it to evade detection by a dog’s immune system. That is the only way it can survive for long enough to get passed on. Understand how all this happened, and we might get some clues to the differences between aggressive cancers and unthreatening tumours, allowing us to improve our diagnosis and treatment options for human tumours.

We already know that some mutations which lead to pre-cancerous tumours in the breast and prostate can be less problematic than the results of our aggressive and sometimes unnecessary treatments. Now, thanks to an old dog teaching us new tricks, we might learn why.

Stock photo: Getty Images.

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At The Edge of Uncertainty: 11 Discoveries Taking Science By Surprise.

This article first appeared in the 05 February 2014 issue of the New Statesman, Cameron the captive

Steve Garry
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The footie is back. Three weeks in and what have we learned so far?

Barcleys, boots and big names... the Prem is back.

Another season, another reason for making whoopee cushions and giving them to Spurs fans to cheer them up during the long winter afternoons ahead. What have we learned so far?

Big names are vital. Just ask the manager of the Man United shop. The arrival of Schneiderlin and Schweinsteiger has done wonders for the sale of repro tops and they’ve run out of letters. Benedict Cumberbatch, please join Carlisle United. They’re desperate for some extra income.

Beards are still in. The whole Prem is bristling with them, the skinniest, weediest player convinced he’s Andrea Pirlo. Even my young friend and neighbour Ed Miliband has grown a beard, according to his holiday snaps. Sign him.

Boots Not always had my best specs on, but here and abroad I detect a new form of bootee creeping in – slightly higher on the ankle, not heavy-plated as in the old days but very light, probably made from the bums of newborn babies.

Barclays Still driving me mad. Now it’s screaming from the perimeter boards that it’s “Championing the true Spirit of the Game”. What the hell does that mean? Thank God this is its last season as proud sponsor of the Prem.

Pitches Some groundsmen have clearly been on the weeds. How else can you explain the Stoke pitch suddenly having concentric circles, while Southampton and Portsmouth have acquired tartan stripes? Go easy on the mowers, chaps. Footballers find it hard enough to pass in straight lines.

Strips Have you seen the Everton third kit top? Like a cheap market-stall T-shirt, but the colour, my dears, the colour is gorgeous – it’s Thames green. Yes, the very same we painted our front door back in the Seventies. The whole street copied, then le toot middle classes everywhere.

Scott Spedding Which international team do you think he plays for? I switched on the telly to find it was rugby, heard his name and thought, goodo, must be Scotland, come on, Scotland. Turned out to be the England-France game. Hmm, must be a member of that famous Cumbrian family, the Speddings from Mirehouse, where Tennyson imagined King Arthur’s Excalibur coming out the lake. Blow me, Scott Spedding turns out to be a Frenchman. Though he only acquired French citizenship last year, having been born and bred in South Africa. What’s in a name, eh?

Footballers are just so last season. Wayne Rooney and Harry Kane can’t score. The really good ones won’t come here – all we get is the crocks, the elderly, the bench-warmers, yet still we look to them to be our saviour. Oh my God, let’s hope we sign Falcao, he’s a genius, will make all the difference, so prayed all the Man United fans. Hold on: Chelsea fans. I’ve forgotten now where he went. They seek him here, they seek him there, is he alive or on the stairs, who feckin’ cares?

John Stones of Everton – brilliant season so far, now he is a genius, the solution to all of Chelsea’s problems, the heir to John Terry, captain of England for decades. Once he gets out of short trousers and learns to tie his own laces . . .

Managers are the real interest. So refreshing to have three young British managers in the Prem – Alex Neil at Norwich (34), Eddie Howe at Bournemouth (37) and that old hand at Swansea, Garry Monk, (36). Young Master Howe looks like a ball boy. Or a tea boy.

Mourinho is, of course, the main attraction. He has given us the best start to any of his seasons on this planet. Can you ever take your eyes off him? That handsome hooded look, that sarcastic sneer, the imperious hand in the air – and in his hair – all those languages, he’s so clearly brilliant, and yet, like many clever people, often lacking in common sense. How could he come down so heavily on Eva Carneiro, his Chelsea doctor? Just because you’re losing? Yes, José has been the best fun so far – plus Chelsea’s poor start. God, please don’t let him fall out with Abramovich. José, we need you.

Hunter Davies is a journalist, broadcaster and profilic author perhaps best known for writing about the Beatles. He is an ardent Tottenham fan and writes a regular column on football for the New Statesman.

This article first appeared in the 27 August 2015 issue of the New Statesman, Isis and the new barbarism