For the first time researchers have sequenced the complete genome of a cancer cell, and they say the process turned up eight previously unknown genetic mutations that played a role in the patient’s terminal leukemia. As it gets cheaper and easier to decode entire genomes, as opposed to just checking “usual suspect” stretches of DNA, doctors hope to decode the genomes of many different types of cancer. Eventually, researchers say cheap techniques may allow doctors to study the cancer genomes of individual patients.
Lead researcher Richard Wilson said he hoped that in 5 to 20 years, decoding a patient’s cancer genome would consist of dropping a spot of blood onto a chip that slides into a desktop computer and getting back a report that suggests which drugs will work best.“That’s personalized genomics, personalized medicine in a box,” he said. “It’s holy grail sort of stuff, but I think it’s not out of the realm of possibility” [The New York Times].
In the study, published in Nature [subscription required], researchers compared tumor cells and normal, healthy cells all donated from a woman who died of leukemia in her 50s. The comparison allowed them to identify mutations that occurred only in the cancer cells. None of the researchers knew what to expect for the number of mutated genes in the cancerous cells. “We were flying blind,” says [study coauthor Timothy] Ley [Science News]. They finally identified 10 significant mutations that appeared to encourage tumor growth and allow the cells to fight off chemotherapy; eight of those mutations had never before been linked to leukemia.
Researchers also studied tumor samples from 187 other patients with the same form of leukemia, called acute myeloid leukaemia (AML), but found that none had the eight newly discovered mutations. Dr Richard Wilson said: “This suggests that there is a tremendous amount of genetic diversity in cancer, even in this one disease. There are probably many, many ways to mutate a small number of genes to get the same result, and we’re only looking at the tip of the iceberg in terms of identifying the combinations of genetic mutations that can lead to AML” [BBC News].
However, that daunting variety doesn’t mean that a new drug would have to be developed for each individual patient, said Wilson. “Ultimately, one signal tells the cell to grow, grow, grow,” he said. “There has to be something in common. It’s that commonality we’ll find that will tell us what treatment will be the most powerful” [The New York Times].
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Image: Timothy Ley
November 6th, 2008 at 11:48 am
What ever the signal is to “grow,grow, grow”. Like anything else,Cancer trigger/signal cells can be destroyed with “heat”, “starved” of nutrients, or killed with “drought”. Throwing more and more drugs at it, does not seem like the commonsense approach, to solving this problem, as we have been throwing drugs at this problem for well over 50 years, to no real effect. We use chemicals, to kill weeds but over time, they still come back, and spread, unless you use those chemicals over and over again. Promoting good cell genes, to fight the cancer “trigger”genes,seems like a more human way to solve the trigger gene problem. I would hope that “drug money” is not the only solution to this crisis. Finding the gene trigger is the key. But once that is discovered, it is up to scientists to find a way to kill these specific “triggers”. I realize drugs can be “specific”, but even these seem to always have side effects that can become deadly,”to healthy cells”, over time. After over 50 years of throwing drugs at this problem, we stil have hardly “Cured Cancer”…
November 7th, 2008 at 11:23 am
medicine is “practiced”. drugs have been effective in slowing the spread of cancer cells “have they not?” people are alive today because of cancer cells being slowed or put into remission with the use of treatment and drugs. it seems to be the way of nature. predator and prey. you either defeat the predator or you are prey. as you say, promotion of “good cell genes” to fight cancer trigger genes seems a more humane way of dealing with cancer, however, drugs are probably effective in giving these good cell genes a leg up in this fight. it seems logical to me that if cancer is elimated some other predatory issue aganist the human body will arise. medicine “drugs and treatment” probably will never reach the garden of eden. you know? the place in bibical history where predation did not exist. surely some research is being done with the profit motive in mind. whatever the reason “thank you” whoever and wherever you are.
November 7th, 2008 at 6:24 pm
More people die from diarrhea than from cancer, yet cancer sees more money in terms of research, prevention, and treatment. If we reallocated half our spending on cancer to the prevention and treatment of other diseases, we would save many more lives. In developed nations we are lucky that cancer and Alzheimer’s disease are problems. It just means we’re not dying young from diarrhea or malaria. The drug companies make money by telling us we should fear cancer more than we really should.
November 8th, 2008 at 2:32 pm
DAVID,I find your comments interesting. will comment later. check it out. must run.
November 9th, 2008 at 4:42 am
David:{more people die from diarrhea than from cancer}. seems like apples and oranges. people will fight what ails them. I sense a bitterness or fustration in what you wrote. few would blame you. all the countries[excluding those barred or opting-out] come together in what is known as the “united nations” and in the last fifty years one would think that among all that representation there would be enough humanity to address and satisfy us all regarding diarrhea,malaria,nutrition….[if we reallocated half our spending on cancer to the...] this is sheepish! a common condition in this country. you seem to have availed yourself to the idea that what we are spending on cancer is the limit.let’s edit some ear-marks or other pork and spend twenty times what we currently do.let’s then hold the UN accountable.your last sentence requries aseperate reply!
November 9th, 2008 at 6:14 am
David, you say the drug companies make money by telling us we should fear cancer more than we should. hey ! your not one of those conspiracy guys are you? you don’t think there is a cure for cancer but it’s being kept from us because there is more money in the treatment, do you? here in the U.S.A. we treat our health as a commodity. thus the profit motive. thus the corporations. do you think that a drug company would carefully word something to make it sound better than it really is? I do also. other corporations with stellar performances: tobacco companies selling poison, grudgingly displaying the warning lables larger and larger over the years. GM’s mathmatics: expense to change gas tank design or settle the wrongfull death cases.they choose settlements and it saved them money!Ford:the same calculations.drug companies are behaving as expected.mabey we should not treat our health-care as a commodity.how about that?
November 30th, 2008 at 11:05 pm
Also to David, more people on EARTH die from diarrhea than cancer. In first world nations, such diseases aren’t as rampant and aren’t a very big issue. Cancer, however, has always been one of those that’s out of our control due to the lack of solid treatment methods. It still isn’t the biggest source of death, but it is probably the one we know the least about and therefore should do the most research on.
Yes, it may seem selfish to focus so inwardly, but lets imagine this on a smaller scale; you have a fish tank and your friend has a fish tank. You look at their fish tank, always concerned about their fish, then your fish die. It’s self preservation, and as cruel as it may seem, if everyone looked at everyone else’s problems, we would probably all die out.