Common Diabetic Drug Fights Cancer Stem Cells

SubtleGuest writes "In the latest issue of Cancer Research, a breakthrough study shows that Metformin, a cheap and common diabetic medicine, kills cancer stem cells — the cells postulated to be responsible for tumor resistance and recurrence after chemotherapy (research abstract here). It has been known that diabetics taking Metformin experience lower cancer rates, and now it is apparent why that may be and how it may apply to non-diabetics as well. When combined with Doxorubicin to kill non-stem cancer cells, the results are nothing short of astonishing: total remission in a mouse xenograft model. The results are achieved at levels below the dosage needed for diabetic control, opening many new avenues in cancer treatment and prevention."

Non-human model systems

[sumthinboutjesus]

I think we shouldn't get overexcited yet; these results have only been shown in a mouse xenograft model i.e. a mouse that has human tissue transplanted. Normally these mouse models are completely immunodeficient or else they wouldn't be able to accept a human transplant. Translating these results into some meaningful treatment for normal adults is highly likely to face a lot of roadblocks and complexities. The human immune system alone is much more complex than the mouse immune system, so you have to remember that animal models more often than not don't translate into meaningful human results. Sometimes they do, and that why model organisms exist, but I'm not putting my eggs in this basket just yet; when I see double blind randomized controlled human trials show positive results then I might believe this has potential to work.

Re:I feel jealous

[siloko]

I wish I was a mouse. Then I'd get all the good cancer treatments.

Forgetting of course that the only reason you have cancer in the first place is because you were force fed 300 cigarettes per day. That's what I read anyway . . . and free cigarettes are cool, but that many!?

The elephant in the room...

[Fished]

It's worth mentioning that low-carb diets have also been shown (at least preliminarily) to restrict tumor growth. See http://www.time.com/time/health/article/0,8599,1662484,00.html [time.com]. I wonder whether part of Metformin's effect might be related to it's lowering of blood sugar, above and beyond the direct biochemical mechanism mentioned in the article.

Is medical advancement stagnating?

[Kirin Fenrir]

I never quite understand these stories; maybe it's because I have difficulty grasping the complexities of medicine (as many people do and aren't aware they do), but doesn't it seem like the discovery of a treatment and the implimentation of a treatment have become abnormally distant from one another? Far beyond what proper testing and trials should mandate?

Is this a patent problem?
A legal one?

It's starting to seem like we've all but halted the advance of medicine while we try to extract as much profit from each new discovery as possible, nevermind that real people are dying in the meantime. How long is it before this drug treatment is avaliable? 2025?

Again, I have little grasp of medicine, so maybe I'm being paranoid. Can anyone give greater perspective on my concern?

Re:Oh! No! Cure for cancer found.

[Anonymous Coward]

Cure for cancer found, people are going to live longer, it will definitely cut into the company profits.

I know you're being sarcastic, but I've never understood that argument. If your health insurance subscriber lives a longer and healthier life, aren't you collecting more money from them?

Re:I feel jealous

[Metasquares]

Many of the mice used in research are transgenic; that is, they're genetically modified in such a way that they're predestined to develop cancer. Others, such as the mouse described in the summary, have tumors implanted in them. When testing a treatment (rather than a cause), exposure to environmental carcinogens to promote development of a tumor is less common.

In any case, be glad you're not a lab mouse. Sometimes even the survivors are killed off at the end of the experiment (though this is becoming less common, particularly in cases where the mice are left in no lasting pain or disability).

Re:Is medical advancement stagnating?

[fuzzyfuzzyfungus]

It'll probably be a bit faster in this case(since the drug in question is already approved, and has a decent amount of clinical history, for diabetic use, the question of safety should already be mostly addressed); but the problem, in general, is that the point where media reports of "discovery of a treatment" start to occur tends to be somewhere in the "promising animal research" stage or even in the "intriguing in vitro results" stage.

At that point, you still have to move on and make sure that it doesn't kill humans(inordinately often, that is, risks are worth it if the disease, or the current best care has worse risks) which takes time and careful testing, and that it actually has the effect desired in humans, more time and testing, and finally roll out.

Drug companies are, undoubtedly, willing to behave downright evilly when it is in their interests. In this case, though, their interests are largely aligned in favor of the swiftest deployment possible. Every day you are working on a drug and unable to sell it, you are losing money on that drug. If your competitor has a drug and you introduce a new one that does the same thing or better, you'll gain some market share. Even if the existing drug is your drug, its patent protections are ticking away, and you really want to have something new ready to go before they expire. You could try just sitting on a new drug, and milking the old one; but, if you patent the new one, its patent protections will also be ticking away, so you'd be insane not to start selling it, and if you don't patent, somebody else might.

You'll note, as well, that most of the stories of drug company malfeasance involve playing up the drug's efficacy or playing down its risks, or pushing doctors to switch from old stuff to new stuff, or encouraging them to prescribe existing drugs "off label" for conditions other than the ones they were originally approved to treat. All of those actions suggest pressure in the direction of faster adoption.

Also of note is the fact that disease is really common and tends to strike a broad cross section of people(some diseases more than others, of course. Some are virtually random, some have pretty strong demographic or genetic factors). Odds are very good that a fair number of key players in any big pharma/FDA sandbagging conspiracy(executives, officials, scientist who could blow the whistle) are either themselves sick, or have sick friends/family/pets, or both. An alarming number of people will screw over strangers for money, particularly if they don't have to see it happen, or feel personally responsible; and sociopaths would do the same to friends and family; but the payoff would have to be amazing for them to put themselves at serious risk. If it turns out that key players in medical research are using very different therapies than those that are generally recommended, it would be time to worry. As long as they and their families and friends are using basically the same techniques as everybody else, though, they have a pretty strong human incentive to do their jobs well.

Obviously, I'm not going to claim that there are never instances of sandbagging. I'm sure that there have been circumstances where, for whatever reason, an incentive existed, and I don't find it at all hard to believe that they went ahead and delayed. However, it seems quite unlikely that that is a major influence on medical development as a whole.

More metformin news

[imgumbydamnit]

I read this item immediately after reading the A Genetic Fountain of Youth [technologyreview.com] article in Technology Review. There on page two:

The new study also implicated the protein AMPK, a component of the TOR pathway even further downstream than S6K1, as a key potential drug target. The role of AMPK is especially intriguing because it is activated by metformin, a widely prescribed drug for treating type 2 diabetes. Withers says this means it may be possible in the next few years to design clinical trials that would test metformin's ability to prevent or treat age-related diseases.

Re:Non-human model systems

[hackingbear]

Probably. But the drug companies cannot monopolize all researchers. Maybe they can buy this group, but once the idea sneaks out, other research groups will try, for their own money and ego. And so the drug companies have to buy them as well. Eventually, just starting on this research will be a get-rich-quick schemes for all the research labs of every college and hospitals around the world. Can the drug companies afford to drag into making these infinite payments? If so, that may be a good thing.

Re:The elephant in the room...

[Anonymous Coward]

That looks interesting. One question, though. How do you set up a double blind experiment for high fat food? If you can't do the double blind, how do you compensate for placebo effect?