Nanoflowers (08.30.05) - Scientists are constructing tiny bouquets of flowers -- smaller than the width of a human hair -- that could be used as the ultimate waterproof coating.
Nano's Downside? (10.07.04) - Nanotechnology, the new science of the very small, could help clean up our air and water, and warn us about pollution or poisons. But maybe some extremely tiny nanosized particles could harm us, too.
Canine Cancer (12.16.03) - Researchers may have found a way to diagnose Alzheimer's disease with a couple of simple eye tests. Mapping the dog genome could shed new light on the cause of different cancers.
Nausea, fatigue, hair loss -- chemotherapy can feel as destructive as the cancer it's fighting. But as this ScienCentral News video reports, researchers now say there may be a way to reduce many of chemotherapy's side effects and improve the precision of the treatment using a nanotechnological smart bomb.
Tiny Anti-Cancer Army
For any cancer patient, the decision to opt for chemotherapy is a double-edged sword.
"Chemotherapy drugs by nature are cytotoxic, meaning that their job is to kill cells," says Harvard University physician-scientist Omid Farokhzad. "The problem is that they're not selective enough or smart enough to know which cell is a cancer cell and which cell is a normal cell."
To tackle this problem, Farokhzad and his colleague Robert Langer at MIT, designed tiny chemotherapy-loaded shells that are only attracted to cancerous cells. These smart nanoparticle shells are studded with chemical homing devices that can tell cells apart by what's on their surface.
"The surface of the cell that has now become cancerous looks different. It has other molecules on its surface that [are] absent on the surface of the normal cells," explains Farokhzad.
The homing devices on the nanoparticles are actually short strands of RNA called aptamers, which can latch onto those signature molecules that are only present on the surfaces of cancer cells. The cancer cells then absorb the nanoparticles, which once inside, release their deadly chemo payload.
As reported in Proceedings of the National Academy of Sciences, the researchers compared treatment with these chemo-loaded nanoparticles to regular chemotherapy in mice with prostate cancer. They found that the mice treated with a single dose of the nanoparticles had significantly reduced tumors -- in fact most of the mice had total tumor elimination. By contrast, the group given a dose of regular chemotherapy had no tumor reduction and a high mortality rate.
"That's no surprise to us because chemotherapy often requires multiple cycles to be effective. But in this case, a single administration of the nanoparticles resulted in eradication of the tumors in five of the seven mice that we treated," says Farokhzad.
He also adds that the nanoparticle group had far fewer negative side effects like weight loss and reduced white blood cell count. "So our system was both significantly more effective than the way chemotherapy is given today and also remarkably less toxic," says Farokhzad.
The researchers claim that the nanoparticles were designed to be very safe to begin with in the hopes of getting them approved as a therapy in humans as soon as possible.
"The design of this particular set of nanoparticles was to make them of all kinds of materials that have already been put in the body or that already exist in the body. So for example the core of the nanoparticles is made out of things that are going to degrade into water and carbon dioxide," explains Langer.
Even though these particular ones tested in the mice were designed to seek out and destroy prostate cancer cells, the researchers say that the nanoparticles can be designed to target many other cells.
"I think this approach is relevant not only to all cancers, but to other diseases, including cardiovascular disease, where you want to target drugs to specific places in the body," says Langer.