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Nanotech Trojan Horse That Kills Cancer
An anonymous reader writes "University of Michigan scientists have created the nanotechnology equivalent of a Trojan horse to smuggle a powerful chemotherapeutic drug inside tumor cells - increasing the drug's cancer-killing activity and reducing its toxic side effects." From the article: "The drug delivery vehicle used by U-M scientists is a manmade polymer molecule called a dendrimer. Less than five nanometers in diameter, these dendrimers are small enough to slip through tiny openings in cell membranes. One nanometer equals one-billionth of a meter, which means it would take 100,000 nanometers lined up side-by-side to equal the diameter of a human hair."
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~ |rip/\/\aster /\/\onkey
I know that this technology is supposed to be helpful, but something about the process makes me feel uncomfortable.
How do they get the horse so small?
-- Jessica Simpson
Trojans infect my system
Therefore Windows = Cancer
Symantec has already identified the Trojan and released an upgrade to its popular Norton Anti-Virus software.
"If you are using Norton Anti-Virus, you do not have to worry about having your cancer cured without your knowledge," a spokesperson said.
It's supposed to be completely automatic, but actually you have to press this button.
Or does this chemical only attack cancer cells, and the dendromere helps it into all cells?
autopr0n is like, down and stuff.
One nanometer equals one-billionth of a meter, which means it would take 100,000 nanometers lined up side-by-side to equal the diameter of a human hair.
I'm sorry, but I just don't get it. How many of these suckers can I fit in a Library of Congress?
We recently had heard in the office over one of the Yellow Machine that's made by Anthology Solutions.
The real news here, if I can interpret the press release correctly, is not that the nanoparticle is the trojan horse, but that its small size *allowed* the researchers to construct the trojan horse.
The article summary is a bit brief- basically, cancer needs a lot of folate. Moreso than normal cells. These folks attached both an anti-cancer drug and a bunch of folate to a nanoparticle, which, due to both its small size and tasty-looking folate, is able to enter cells and deliver the anti-cancer payload rather than slowly diffuse it through the cell wall.
This is still a bit of a shotgun approach, as normal cells still get targetted to some extent, but *much* less so than previous methods.
In case you are like me and you just want to know how they targetted the cancer cells, this is a very brief rundown:
All cells require folate to survive. Cancer cells suck up folate like it's crack. They put the poison in the folate. All cells absorb some of the poisoned folate. Cancer cells absorb most of it.
Pretty nice idea, but it made me wonder about the push to get expectent mothers to take excessive amounts of folic acid (folate). Does that make them more prone to cancer by giving the cancer cells extra food?
The previous comment is purposely vague and generalized, but all of the facts are completely true.
Protesters stripped down naked to protest the University of Michigan's support of nanotechnology. One protester stated, "Nanotechnology is bad because it is umm, err... Nevermind I am just gonna get naked cuz its bad."
News Reporters Make Tasty Polar Bear Treats!
Lastly, some folks asked about what happens to all those dendrimers when they've done their job.
Wrong kind of nanotech. If you read the article you would've seen that all they have developed is a polymer molecule. The "grey goo" would come from nano machines that self replicate. That has nothing to do with this.
-- Thou hast strayed far from the path of the Avatar.
Nice to see this start to happen.
.1% of it, and also enable us to up the dose as relevant only to the affected parts.
Based on what I understand of nano-tech and the human body, I think we're going to see a lot more of this, and this will be the first medical nanotech revolution: Creating drugs that are targetted only at the things they are supposed to affect.
Imagine wrapping, say, kidney drugs in a nanotech container that only opens in the kindeys, and is otherwise harmless. Or imagine an anti-inflammatory that only targets inflamed areas.
This will cut down a lot on undesirable side-effects caused by flooding the entire body with something to affect
This obviously doesn't apply to everything, but this is the first advance I expect to actually get used. We're a long way from lil' machines that can safely clean out plaque from our arteries (though we recently saw some advances towards doing it unsafely this last week), but this is quite doable, I think.
Is this a biodegradable polymer?
How hard is it to attach molecules to these tree-like structures? If these polymer dendrimer are exposed to various other molecules will some bond naturally, or do they have to be tailored to a specific molecule?
Does that mean that in potential future patients, any free/unabsorbed nanoparticles will be excreted into the public sewage systems, and being (I assume) unfilterable, thereby enter the earths water cycle?
So when you put those together, will these nanoparticles be able to float freely in our oceans and rivers, their dendrimers bonding with molecules found in nature, and then if conditions are right potentially take those molecules inside our cell walls?
I know - the actual number of these things for cancer patients will be really small, but workable techniques tend to get expanded, and if they don't break down they'll just pile up over time. I'm not qualified to do anything but ask these questions, I'm just wondering whether there's any reasonable risk that once these hit the outside world they could turn around and be just as effective at delivering cancer-causing agents they pick up randomly from the environment.
The only acceptable defense of scientific results is to say that they were the product of the Scientific Method.
it would take 100,000 nanometers lined up side-by-side to equal the diameter of a human hair.
Yeah, but you would never get that many in a row a one time. They are like cats!
"In a related trail, (refer: http://www.pedsdoc.com/index.php?name=News&file=ar ticle&sid=12 [pedsdoc.com]) in 1999, 18-year-old Jesse Gelsinger died during a gene therapy clinical trial at the University of Pennsylvania...."
Related how? The study from TFA is a directed drug delivery study using as a carrier a non-immunogenic (in mice, anyway) man-made dendromer. The Gelsinger trial was a gene therapy trial using adenovirus (a common cold virus) as a vector to carry corrective DNA to cells. IIRC, Gelsinger had an extreme immune reaction to the vector, a fairly common occurance when using as a vector a virus that the immune system has almost certainly seen previously and been primed to combat. These studies are quite different from a physiological/immunological standpoint.
I sent the link to my wife, an Oncology Nurse Practitioner. She said that this type of transport mechanism isn't all that new.
She went on to say that they've already packaged Taxol (a breast CA chemo) in a similar way and supplied this link for more info. It's called Abraxane.
As a person recently diagnosed with cancer and currently in chemo, I find more than passing interest in this story. Although, very clearly the approach described here isn't going to help me, I've spent a lot of time researching cancer therapies of various types and I feel qualifed to comment.
Cancer isn't one disease, it's a group of related diseases. A solution that works for say breast cancer may or may not work for other cancers. The idea of targetting cancer cells specifically for apoptosis (cell death) isn't new but the idea of using a delivery vehicle that can have a deadly payload seems to be somewhat novel.
There are a number of other drugs in development that might have a similar effect. Also there are human clinical trials already in progress for methods of creating a vaccine tailored to a specific person by using that person's tumor. Given that a phase 1 trial of the approach described in the article will not start for two years and that trials generally take at least 7 years before approval, it's likely that other equally novel delivery methods will be approved substantially before this one. This approach will have to show it's better than the others that will be on the market already when approval time comes along.
With some popular cancers such as breast and colorectal cancers, it's quite likely that there will be better therapies. However, if this approach can be targetted to the really deadly cancers (like lung and ovarian cancers) or the many cancers that don't have any good treatment options, this could be a real winner. If you can wait long enough before getting your disease.
The term "nanotechnology" has entered the public lexicon, much like the word "nuclear" in the middle of the 20th century. As soon as that happens, researchers start calling everything "nanotechnology" because a bunch of senators see a presentation from the RAND corporation that says "nanotechnology" can do this if we fund it at level X or this if we fund it at level Y and they create things like the "nanotechnology" initiative. Now the fields of biochemistry, chemistry, and molecular biology fall under the broad definition of "nanotechnology" and because engineers and physicists want a piece I routinely see slides of micrographs labeled "nano_____". I understand the need for funding, but I'm so @#$% sick of nano- motors, latters, elevators, delivery systems, power plants, putians, pumps, gears, etc. plastered on everyone's research that 4 years ago would have been called supramolecular, polymer, or materials. Its nice to see clever things like this (which BTW is not unique to this lab, there are entire conferences on dendrimers now) that actually seem to work, but aren't really nanotechnology. Sure dendrimers are on the nanometer scale, but if we run around calling everything that is nanscale "nanotechnology" what will the point of words like polymer, protein, macromelecule, or even nanoscale be anymore? Well, maybe I just need to get with the times. All I ever hear from people in suits is how we need to "rebrand chemistry" and start making flashy presentations that will play well in layman's publications. I'd like to roll their ties up and cram them down their far-too-often-open mouths, but I seem to be in the minority as far more people are using pretty pictures and stupid puns, cliches, and analogies to hype their research than adhering to the old "scientists are modest; the research speaks for itself" philosophy.
Now that my rant is done, on with this whole business of idiots protesting stuff they don't understand. Two examples, genetic engineering: ok through artificial selection (tomatoes, chickens, dogs, corn... basically everything humans have domesticated), evil through "cloning" which they don't even know the definition of. Nuclear: bad, bad, bad, unless it is to keep the Reds at bay. Like how Nuclear Magnetic Resonance Imaging was rebranded Magnetic Resonance Imaging (MRI) because (seriously) people wouldn't stick their heads inside something with the word "nuclear" in it (yeah, those processing nuclear spins are going to kill you)... Anyway so thanks to people spreading fear and paranoia under the banner of "nanotechnology" involving tiny robots that consume matter at the atomic level or little nanothingers that enter your body and control your mind, coupled with the desire to pile gobs of scientific research under the same banner (to get funding) we wind up with hippies protesting pants. In some ways paranoia is a good thing becuase it helps us stay skeptical, but c'mon... pants? So the way I see it, that is how dendrimers which don't significantly differ chemically from styrofoam, platic bags, ketchup bottles, or any other man-made macromolecule wind up the inadvertant target public fear, despite having great technological potential. I suppose it is like stem cell research in that ideology (i.e. preconceived notions) trump fact, reality, common sense, and science.
Actually, I wrote my thesis on life experience.