The other day a news release with this headline landed in my email: "McMaster University researchers discover drug destroys human cancer stem cells but not healthy ones." Of course, the writers of the press release know, that I know, that the discovery didn’t just happen in the last few days. The headline is press release code for: "our researchers have been working on this for a few years and they are about to be published in a prominent medical journal, and if their work is deemed significant enough for Cell, it might also be interesting enough for the daily news." Then it’s up to the folks here at the CBC Health Unit to decide, "is it news?"
It’s something we struggle with every day, trying to decide when to report on raw, technical and basic scientific discoveries, and how to avoid exaggerating the impact of these early, incremental developments.
It’s tempting to get excited. After all, killing cancer cells is one of the major goals of medical research. The problem is, most of the time, in these early stages, scientists are killing cancer cells in petri dishes or mice, not in living, breathing humans. Still, if the discovery is published in a prestigious journal, that, by itself, is an impressive achievement. We are flooded with advance media notices, from the journals, the research institutes and others, all wanting to make sure we know about upcoming publications. But if a Canadian scientist ends up in Nature, or Science or Cell, is that, by itself, newsworthy? Even if the discovery is so early and incremental that it will be a decade, or more, before it makes any contribution to human health, if ever?
Right now, new technology is allowing researchers to throw all kinds of molecules at cancer cells, to see what happens. If a molecule cripples the cancer cells’ ability to proliferate, or causes some other disabling effect, it could, one day, after much research, and many clinical trials, become a new drug, another weapon to add to the cancer arsenal. For the scientists, and others in the drug industry, the race begins to try to answer that question, to push the discovery into the crowded pipeline, to leap into the fight for limited resources to find money for further research, for clinical trials on humans, to see if the molecule works the same way on people as it did in the test tube or in mice. But for most of us, the discovery won’t change anything, except to spark hope that a new cancer breakthrough is imminent, a potentially hazardous side effect to the headline that I will talk about in a moment.
Many things can go wrong along the way, things that will never be reported in the news. The potential drug might fail to show any effect in humans, or it might be toxic, or it might not capture the interest of a drug company and thus might never be pushed through the system. And at the end of it all, if it survives, it might turn out to be no better than drugs already in use. If all goes well, and it clears all the hurdles, at best, it will join the other drugs in the pharmaceutical toolbox and help to turn the 200 or more diseases that we call 'cancer' into chronic, treatable conditions. All important work in the business of advancing medicine, but is every one of the those discoveries, if-everything-goes-well-over-the-next-ten-years, news? And does reporting on that very early glimmer of potential end up doing more harm, by raising the desperate hopes of anxious cancer patients?
It has happened before.
Flash back to 2007 and this headline, "Long-used drug shows new promise for cancer." The drug, in that case, was dichloroacetate, or DCA, a generic drug used to treat rare metabolic disorders. When researchers at the University of Alberta in Edmonton tested it on cancer cells, they discovered that it seemed to flip a switch, turning on a mechanism that causes abnormal cells to die. Again, really cool science. But was it news, when no one knew if it would work?
The media decided, back in 2007, that it was news, and headlines flew around the world, describing a "drug that shrinks cancer cells and can even make tumours disappear." "No nasty side effects," the stories said, just dissolve the powder in water, for a mere $2 a dose. One story suggested the discovery could "soon be used to treat many forms of cancer."
Patients began demanding the drug, even before a single human trial had happened. They started buying it from unscrupulous dealers selling powder that in some cases didn’t even contain the effective ingredient. A U.S. court convicted an Edmonton man for selling corn starch over the internet and calling it DCA.
Meanwhile, the hope generated by the media coverage inspired a local Alberta community to raise the money for a tiny clinical trial, that under other circumstances might have been funded by a drug company. But this was an abandoned drug, long off patent, and not attractive from a profit perspective. Still, committed researchers at the University of Alberta did the hard work, using donated funds, and completed the first clinical trial on five patients with terminal brain cancer. DCA seemed to have an effect, slightly shrinking the tumors in a few of the patients. We reported on this new development in December 2010, three years after the first story. I asked lead researcher Dr. Evangelos Michelakis if the trial results were as exciting as he thought they would be. He said, "it is exciting for me, but I don’t think anybody could claim this drug works based on this trial because there were too few patients."
So the story ended the same way as it had begun in 2007. The drug shows promise, but it’s a long way from being something patients can use.
At around the same time, a group of researchers at the University of Guelph reported that DCA might not kill cancer cells, but, in fact, might make things worse, by protecting them. It was a preliminary finding, and needed further study, but it’s an example of the kind of complicating questions that arise as early discoveries are tested.
So where does DCA sit now, five years after the original excitement? Stalled, due to lack of interest, according to Dr. Michelakis. "We have not initiated another clinical trial with DCA in cancer," he told me in an email this week, "It was my hope that other centres, independent of us, will be inspired to do similar trials, but I have not seen any signs that this is the case."
"I am also disappointed that other investigators have not been interested to test this drug with proper trials on their patients," he added, "but I understand that without funding (although DCA itself is very cheap) this is very difficult. As I had said in the beginning of this work, taking a generic drug to patients with a deadly disease is as difficult a task as one can imagine in modern medicine, and it requires many people to participate and push the agenda. One person in one centre cannot do it."
But he has not abandoned research on DCA. Just this week, he has had another paper published in the Journal Oncology, online ahead of print. The paper describes another discovery about DCA, that suggests it can inhibit angiogenesis, (the development of blood vessels), and possibly cut off a tumor’s blood supply, a goal of drugs like Avastin, that have so far failed to live up to their early, and much publicized, promise.
"Our work points to the fact that to inhibit angiogenesis long term, the Avastin-like drugs are not enough because they inhibit the pathway quite downstream allowing the tumor to escape upstream," Dr. Michelakis said in his email, adding that the mechanism he has identified might work better because it happens earlier in the process.
Once again, we're still at the beginning of the story. After all the trials, and the set-backs, DCA might or might not become another weapon in the fight against cancer.
And what about the stem cell killer from McMaster? It might also lead to a future cancer therapy, one day. Or it might not. And what about the dozens of other intriguing discoveries that are jamming up my email right now? It’s all really cool science, but is it news?