Cancer’s ‘magic bullet], a term which has been around for decades, is falling into disuse and deservedly. So it’s disturbing to see it used by someone in McGill University’s (Montreal, Canada) communications department for a recent breakthrough by their researchers.
The reason ‘magic bullet for cancer’ has been falling into is disuse because it does not function well as a metaphor with what we now know about biology. (The term itself dates from the 19th century and chemist, Paul Erlich.) It continues to exist because it’s an easy (and lazy) way to get attention and headlines. Unfortunately, hyperbolic writing of this type obscures the extraordinary and exciting work that researchers are accomplishing. From the news release on the McGill website (also available on Nanowerk here),
A team of McGill Chemistry Department researchers led by Dr. Hanadi Sleiman has achieved a major breakthrough in the development of nanotubes – tiny “magic bullets” that could one day deliver drugs to specific diseased cells.
The lead researcher seems less inclined to irresponsible hyperbole,
One of the possible future applications for this discovery is cancer treatment. However, Sleiman cautions, “we are still far from being able to treat diseases using this technology; this is only a step in that direction. Researchers need to learn how to take these DNA nanostructures, such as the nanotubes here, and bring them back to biology to solve problems in nanomedicine, from drug delivery, to tissue engineering to sensors,” she said.
You’ll notice that the researcher says these ‘DNA nanotubes’ have to be brought “back to biology.” This comment brought to mind a recent post on 2020 Science (Andrew Maynard’s blog) about noted chemist and nanoscientist’s, George Whitesides, concerns/doubts about the direction for cancer and nanotechnology research. From Andrew’s post,
Cancer treatment has been a poster-child for nanotechnology for almost as long as I’ve been involved with the field. As far back as in 1999, a brochure on nanotechnology published by the US government described future “synthetic anti-body-like nanoscale drugs or devices that might seek out and destroy malignant cells wherever they might be in the body.”
So I was somewhat surprised to see the eminent chemist and nano-scientist George Whitesides questioning how much progress we’ve made in developing nanotechnology-based cancer treatments, in an article published in the Columbia Chronicle.
Whitesides comments are quite illuminating (from the article, Microscopic particles have huge possibilites [sic], by Ivana Susic,
George Whitesides, professor of chemistry and chemical biology at Harvard University, said that while the technology sounds impressive, he thinks the focus should be on using nanoparticles in imaging and diagnosing, not treatment.
The problem lies in being able to deliver the treatment to the right cells, and Whitesides said this has proven difficult.
“Cancer cells are abnormal cells, but they’re still us,” he said. [emphasis is mine]
The nanoparticles sent in to destroy the cancer cells may also destroy unaffected cells, because they can sometimes have cancer markers even if they’re healthy. Tumors have also been known to be “genetically flexible” and mutate around several different therapies, Whitesides explained. This keeps them from getting recognized by the therapeutic drugs.
The other problem with targeting cancer cells is the likelihood that only large tumors will be targeted, missing smaller clumps of developing tumors.
“We need something that finds isolated [cancer] clumps that’s somewhere else in the tissue … it’s not a tumor, it’s a whole bunch of tumors,” Whitesides said.
The upside to the treatment possibilities is that they buy the patient time, he said, which is very important to many cancer patients.
“It’s easy to say that one is going to have a particle that’s going to recognize the tumor once it gets there and will do something that triggers the death of the cell, it’s just that we don’t know how to do either one of these parts,” he said.
There is no simple solution. The more scientists learn about biology the more complicated it becomes, not less. [emphasis is mine] Whitesides said one effective way to deal with cancer is to reduce the risk of getting it by reducing the environmental factors that lead to cancer.
“It’s a biology problem, not a particle problem,” he said. [emphasis is mine]
If you are interested , do read Andrew’s post and the comments that follow as well as the article that includes Whitesides’ comments and quotes from Andrew in his guise as Chief Science Advisor for the Project on Emerging Nanotechnologies.
All of this discussion follows on yesterday’s (Mar.17.10) post about how confusing inaccurate science reporting can be.
Moving onwards to two analogies, lego and pasta. Researchers at the University of Glasgow have ‘built’ inorganic (not carbon-based) molecular structures which could potentionally be used as more energy efficient and environmentally friendly catalysts for industrial purposes. From the news item on Nanowerk,
Researchers within the Department of Chemistry created hollow cube-based frameworks from polyoxometalates (POMs) – complex compounds made from metal and oxygen atoms – which stick together like LEGO bricks meaning a whole range of well-defined architectures can be developed with great ease.
The molecular sensing aspects of this new material are related to the potassium and lithium ions, which sit loosely in cavities in the framework. These can be displaced by other positively charged ions such as transition metals or small organic molecules while at the same time leaving the framework intact.
These characteristics highlight some of the many potential uses and applications of POM frameworks, but their principle application is their use as catalysts – a molecule used to start or speed-up a chemical reaction making it more efficient, cost-effective and environmentally friendly.
Moving from lego to pasta with a short stop at the movies, we have MIT researchers describing how they and their team have found a way to ‘imprint’ computer chips by using a new electron-beam lithography process to encourage copolymers to self-assemble on the chip. (Currently, manufacturers use light lasers in a photolithographic process which is becoming less effective as chips grow ever smaller and light waves become too large to use.) From the news item on Nanowerk,
The new technique uses “copolymers” made of two different types of polymer. Berggren [Karl] compares a copolymer molecule to the characters played by Robert De Niro and Charles Grodin in the movie Midnight Run, a bounty hunter and a white-collar criminal who are handcuffed together but can’t stand each other. Ross [Caroline] prefers a homelier analogy: “You can think of it like a piece of spaghetti joined to a piece of tagliatelle,” she says. “These two chains don’t like to mix. So given the choice, all the spaghetti ends would go here, and all the tagliatelle ends would go there, but they can’t, because they’re joined together.” In their attempts to segregate themselves, the different types of polymer chain arrange themselves into predictable patterns. By varying the length of the chains, the proportions of the two polymers, and the shape and location of the silicon hitching posts, Ross, Berggren, and their colleagues were able to produce a wide range of patterns useful in circuit design.
ETA (March 18,2010): Dexter Johnson at Nanoclast continues with his his posts (maybe these will form a series?) about more accuracy in reporting, specifically the news item I’ve just highlighted. Check it out here.
To finish on a completely different note (pun intended), I have a link (courtesy of Dave Bruggeman of the Pasco Phronesis blog by way of the Science Cheerleader blog) to a website eponymously (not sure that’s the right term) named physicssongs.org. Do enjoy such titles as: I got Physics; Snel’s Law – Macarena Style!; and much, much more.
Tomorrow: I’m not sure if I’ll have time to do much more than link to it and point to some commentary but the UK’s Nanotechnologies Strategy has just been been released today.