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Archive for April 9th, 2012

Why haven’t we cured cancer yet? (Revisited): Personalized medicine versus evolution

About a year ago, I addressed what might seem to the average reader to be a very simple question: Why haven’t we cured cancer yet? As I pointed out at the time, it’s a question that I sometimes even ask myself, particularly given that cancer has touched my life. Three years ago, my mother-in-law died of a particularly nasty form of breast cancer. Even though I am a breast cancer surgeon, I still wonder why there was nothing that could save her (and there still is nothing that could have saved her, if it existed then) from a decline over several months followed by an unpleasant death. Yet, as a cancer researcher, I do understand somewhat. A couple of years ago, I wrote in depth about the complexity of cancer from a science-based viewpoint, as compared, of course, to the incredibly simplistic view that many purveyors of alternative medicine quackery promote as being The One True Cause of Cancer. As I put it at the time, shamelessly stealing from Douglas Adams: Cancer is complicated. You just won’t believe how vastly, hugely, mind-bogglingly complicated it is. I mean, you may think algebra is complicated, but that’s just peanuts to cancer.

I saw more evidence of that at the American Association for Cancer Research meeting last week. In fact, if there’s anything I’ve learned, it’s that developing personalized therapy for cancer is going to be a hell of a lot more difficult than we had ever suspected. Actually, it wasn’t just the AACR meeting that taught me this, but it’s as good a pretext as any to discuss some cool new science. I only wish it was science that pointed an obvious path forward to the development of personalized therapy. On the other hand, if it were easy then anyone could do the “personalized therapy for dummies” approach that, for example, Stanislaw Burzynski takes. Then there’s the even more ridiculously simplistic approach that certain practitioners of “complementary and alternative medicine” (CAM) take.

So why haven’t we cured cancer yet? Again? One reason that I discussed last time I covered this topic concerns a study that used the latest next generation sequencing (NGS) techniques to sequence seven aggressive and advanced prostate cancers. I described the results as these genomes looking like someone threw a miniature grenade into the nucleus of a prostate epithelial cell. In other words, these are some really messed up genomes. (I wanted to use another word to describe it, but this is a family blog—sort of, anyway.) I used this example to explain once again that cancer is not a single disease. It’s hundreds of diseases. Although there are common themes in how cells become cancerous, such as loss of responsiveness to growth signals with a resultant ability to grow unchecked, evasion of programmed cell death (apoptosis), inducing the surrounding tissue to provide a blood supply (angiogenesis), evading the immune system, and invading the blood or lymphatic systems to travel elsewhere in the body and take up shop in other organs, such as liver, lung, or bone, individual cancers acquire these necessary (to the cancer) abilities through many different mechanisms. For this reason, it’s completely ridiculous to speak of a “cure for cancer.”

It’s also the reason I expressed skepticism when Steve Novella discussed a potential universal anti-cancer drug. Ditto when the press breathlessly reports studies suggesting a “universal cancer vaccine.” While these sorts of research findings are promising, they need to be put into perspective. We’ve seen their like many times before, and various cancers are still deadly diseases. In fact, my career intersected with this sort of hype back in the 1990s, when I studied combining angiogenesis inhibitors with radiation therapy in experimental models of cancer in mice. For a period of time in the late 1990s, I lived the hype. Then reality, as it always does, brought us all down to earth. Now, 15 years later, we know that angiogenesis inhibitors, although useful, are not any sort of “magic bullet” cure for all solid tumors. Like many advances before, they have now taken their place in the armamentarium of anticancer drugs, more important than some but not as important as others.

It’s even more complicated than that.

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Posted in: Basic Science, Cancer, Evolution

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