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Altered Immune Cells Help Girl Beat Leukemia
An anonymous reader writes "For decades, one of cancer's most powerful weapons has been to corrupt the human immune system. Finally, researchers in Philadelphia have developed a way to turn that weapon against certain cancers, and potentially open the door to a whole new generation of therapies for all manner of cancers. From the article: 'It is hard to believe, but last spring Emma, then 6, was near death from leukemia. She had relapsed twice after chemotherapy, and doctors had run out of options. Desperate to save her, her parents sought an experimental treatment at the Children’s Hospital of Philadelphia, one that had never before been tried in a child, or in anyone with the type of leukemia Emma had. The experiment, in April, used a disabled form of the virus that causes AIDS to reprogram Emma’s immune system genetically to kill cancer cells.'"
http://xkcd.com/938/
A virus is not lethal. It is merely a vehicle, a means of reprogramming cells. Its hardware. The lethality is in the software.
using lethal viruses to help us combat lethal cancers.
Big deal. Lots of things useful things are lethal. Hell, I was injected with a disabled lethal virus a couple weeks ago. Just in time to keep me from being part of this year's flu season. Pretty much every cancer treatment kills things. That's how they work. The goal is to kill the cancer without killing too much of the person with it.
While I understand your concerns, every medical breakthrough has involved risk.
The polio vaccine could have backfired, but it didn't. You and I have grown up without the fear of a disease that plagued every generation up to our parents.
That's how I always describe chemotherapy to the layman. It's taking just enough poison and hoping that the cancer dies first.
Your link isn't the same research as what the article is talking about though.
The article is about removing a patient's stem cells, using neutered HIV to deliver a payload to them that changes the immune system at a genetic level and then reintroducing the stem cells into the patient. The patient's immune system would then be equipped to kill the cancer. Your link discusses infecting patients with a virus that targets cancer cells preferentially, killing a cancer while at the same time giving the patient only mild symptoms.
On the one had, the article is talking about real, honest to goodness genetic engineering of a living human being which is, quite frankly, science fiction levels of amazing. But it almost universally causes a cytokinetic swarm in the patient as the immune system suddenly knows how to fight massive amounts of what it suddenly sees as infected tissue (actually tumors). The HIV is disabled the same way other viruses are disabled to create vaccines, and even if the patient got HIV somehow that would in fact still be preferable than dying immediately from cancer.
On the other, your article would indicate a cure that would be essentially zero cost to produce. The side affects are minimal but, and this is the proverbial "but" that is probably killing all research on the topic, you also have a virus that is capable of killing the vast majority of one tissue type (tumor) inside the human body. And that is quite frankly terrifying. Until you can quantify how likely or unlikely the virus is to target a different tissue type and how likely is it that the virus is communicable (or could mutate to become so) you won't be trying it out on anyone.
"[using] a disabled form of the virus that causes AIDS"
While true, this is a poor way to describe a lentiviral vector, meant to invoke the idea of using HIV to kill cancer in the minds of readers not familiar with modern molecular biology. HIV is a type of virus called a lentivirus, which itself is a type of retrovirus, which means that it takes the RNA genetic code it has packaged in the virion, chemically transforms it into DNA, and integrates this DNA into the DNA of the infected cell. Lentiviral vectors are designed such that they do this part of the viral life cycle, but are engineered to lack the genes necessary to make more viruses, so the integrated virus is dead on arrival.
In this case, the researchers kept the normal HIV surface receptors so the virus would efficiently target and "infect" T-cells from the patient; normally, lentiviruses are given a generic non-HIV receptor so they can infect any cell type you might be using in your lab experiments. The lentivirus genome contained not the normal viral genes, but a chimeric T-cell receptor designed to stimulate an immune response against CD-19, a surface protein specific to B-cells. Once this chimeric gene is integrated, the T-cells will express it on their cell surface, and stimulate the immune system to target and destroy cells that have CD-19 on them; this kills all the B-cells in the body, both healthy and cancerous. This last point is a problem brought up by TFA, that the patient now essentially has a limited auto-immune disorder as the altered T-cells persist in her body and continue to point them immune system to targeting B-cells, leaving her partially immuno-compromised (which is the funny part about using the "virus that causes AIDS" to do this).
Wow there are a lot of people freaking out they are using HIV for this.
Um, relax, they didn't give the girl HIV, they re-engineered the virus into something new. The virus doesn't replicate in the to host. T-cells removed from the host are exposed to the engineered HIV. The engineered HIV then changes the DNA in the T-cells to allow it to attack cancerous B-cells. The T-cells are then re-injected and do their work. The T-cells continue to replicate, but the engineered HIV is not actually introduced into the body.
It was to me, but I didn't die from aids, nor did anyone I knew.
My neighbor, who had AIDS, died a week ago.
While this doesn't matter to you (it's cool.), it does show that AIDS still affects people and others around people with AIDS.
He ended up with cancer in his bone marrow, was given kemo, but when told he wasn't going to be able to go home again (would require 24 care which he couldn't afford), he chose to stop taking treatments, and died a couple days later. And I don't blame him.
So even it AIDS virus took 50 years off the timeline to finding a cure for cancer, it doesn't matter to my neighbor, because he's dead regardless. But I think he'd be happy to know that even while AIDS was bad for him, it might be doing some good for others.
Be seeing you...
Not just that, but the Virus's physical form is simply a payload mechanism to inject the virus genetic code into healthy cells. The healthy cell that was infected now becomes a virus factory creating tons of new virus cells until it explodes releasing them into your system. There is a very cut and dry hardware to software paradigm here. If we consider that a virus is nothing but a genetic delivery mechanism it instantly becomes the greatest tool humanity has for this type of work. Nothing we can currently create would be even a fraction as effective.
While there are problems with the GP's theory, you may not completely be understanding capitalism yourself, at least as it seems to apply to the pharmaceutical industry. For example, there have been many instances of sweetheart deals between drug manufacturers with expiring patents and manufacturers of generics where the original manufacturer has paid the generic manufacturers _not_ to produce generics. As long as the profit margin is high enough on the original and would be low enough on the generics, it's viable. At least, it's viable enough for long enough that, even if you can't say that the industry outright blocks things, it does have a certain... inertia about it.
You realize that it costs insurance companies about half a million dollars to treat a cancer patient? And most of that money goes to all kinds of different companies many of them struggling on low margins making an assortment of drugs, medical services, and other stuff. Now let's say a company comes out with a cure for cancer .. They can charge $100,000 for it as pure profit .. Insurance companies would gladly pay. 10 million people a year get cancer .. That means the profit will be an absolutely insane $1 trillion dollars a year.
Or forget that .. Steve jobs had cancer and died of it .. All a company that had the cure had to do was call him up and charge him $5 billion cash plus 50% ownership of Apple for the cure.
Holy crap. Imagine if they could make sexually-transmitted cancer cures?
Unfortunately, the population of slashdot will STILL be decimated by cancer. But the rest of the world would have a field day!!
My mother was diagnosed with acute myelodysplastic syndrome in 2006, and the doctors she spoke with talked about this type of treatment. At the time it was not ready for use in humans, however. We did talk for awhile with the doctors about the nature of cancer and this type of treatment.
Many people are aware that cancer is present in almost all people at several times in their lives. The vast majority of cancers are from genetic defects that the body detects as an alien, and it will attack and destroy the mutated cells just as foreign bacteria or a transplanted organ are. Now, the types of cancer that we talk about and that result in terminal illness is from a mutation that is different enough to be deadly and parasitic to the human body, but not different enough to be detected as different.
All cells contain markers that act as identification badges. Last I was aware, there were 10 known genetic markers for humans that determine this identity (only six were known in the 1990's, so this is pretty new stuff). Its these markers that are used to find organ and tissue donors. However, even a perfect 10 out of 10 match is not enough to guarantee that foreign tissue will be detected as alien, so we know that our known list of 10 markers is incomplete. This is why perfect matches still face rejection risks.
The problem then, from a leukemia perspective, is that donor bone marrow will produce white blood cells that see the recipient body as alien, and attack it. That's kind of what you want, since the idea is to kill the cancerous bone marrow, but it's not exactly discriminate about what it will attack. So for leukemia treatment, you don't even want a perfect 10 out of 10 match since that would be counterproductive. Perfect donor bone marrow wouldn't identify the cancer either, and the cancer would relapse.
What this treatment does is gives doctors a way to tell your body that certain cells are aliens by forcefully altering their DNA. Then the body can just fix itself. That's really what medicine does best: allows the body time to fix itself.
"How can this possibly work?" you think. "Aren't all cancers different?" Well, it turns out the answer is "sort of". We categorize cancers based on the kind of tissue that is affected, but that's really not accurate. We should categorize it based on exactly what genetic sequence mutated and in exactly what way. Cancer, then, is literally a family of thousands of diseases with very similar symptoms. Many cancer types are, in fact, mutations of the same segment in the same way. However, now that we are able to sequence the DNA of a human, we ought to be able to accurately categorize each person's individual cancer by sequencing healthy and cancerous cells. We can then design a DNA segment which will only work in the DNA sequence of cancerous cells and that will identify the cells as alien to the body. The body will then attack the cancer, and destroy it. We will, literally, paint a target on the cancer cells for the human body to destroy. The mechanism for delivery of this kind of genetic manipulation is already supplied to us by nature in the form of a retrovirus. In this girl's case, the retrovirus that seeks out her cancerous cell type is HIV, which attacks white blood cells.
This, then, is the most promising path to the cure for cancer. It will not be cured with a single treatment like polio or smallpox, but the method can be applied over and over against every type of cancer.
My mother was given more traditional treatment with a bone marrow transplant. The best match that could be identified was an 8 out of 10 match. Even so she successfully underwent the transplant and survived a year longer than she was given when diagnosed. She then relapsed, and was beginning her second treatment when she died from a massive stroke caused by all the medications required to treat the disease and the anti-rejection drugs and the side effects of the medications. If she had had this kind of option where doctors could reprogram her immune system to seek and destroy the cancerous bone marrow like it's supposed to instead of having to rely on grafted bone marrow that would attack her healthy tissue as well, she might still be alive today.
The road to tyranny has always been paved with claims of necessity.
Wikipedia's Cancer Immunology article discusses this, going as far as how exactly the immune system goes about dealing with development of cancer cells in the body. It's actually a very interesting read, as Wikipedia puts it in relatively simple terms, if you're not familiar with it at all.
I am not sure if the goal of this altered immune cells therapy is to activate this process further or equip the immune system to deal with cancer in a whole new way, though. I would imagine it strengthens this existing response, but I'm no expert on it.
That's more than a little misleading. The drugs used in chemotherapy are chosen because they preferentially kill fast-growing tissue first, such as hair, the intestinal endothelium (lining), and tumour cells. It's not as simple as taking some arbitrary, nondescript "poison" under the assumption that the cancerous tissue is poorly equipped to handle all toxins; specific mechanisms are chosen to limit the impact that the drugs have on the rest of the body.
The GP also made a bad comparison since, as the AC also said, inactivated viruses in this form have no replicative ability whatsoever. They're just gene syringes. These same misconceptions arose the last time we discussed retroviral leukaemia treatments.
Bio questions? Ask me to start a Q&A journal. Computer analogies available for most topics!
The DNA/RNA that a lethal virus injects into cells kills people. That DNA/RNA doesn't need to be lethal, though, for it to be a virus. It will reprogram the cell, in this case to help the person.
"Our two-party system is like a bowl of shit looking at itself in a mirror." - Lewis Black
I said explaining to the layman. They don't care about those details anyway. Certainly they're not going to just grab some rat poison and self-treat based on what I say. It gets to the point and there's few enough details that they can follow the thought process.