Nano World: Nano-drugs cure mouse prostate

April 11, 2006

A single injection of nanoparticles loaded with drugs completely eliminated prostate tumors in mice, experts told UPI's Nano World.

Annually some 230,000 people get prostate cancer, killing 30,000 a year, explained researcher Omid Farokhzad, a molecular biologist and anesthesiologist at Brigham and Women's Hospital in Boston. The current state-of-the-art therapies for prostate cancer either implant radioactive material in the cancer to kill off cells or remove the entire diseased prostate gland. The radioactive therapy can prove effective but can lead to erectile dysfunction, urinary retention and radiation-induced bowel injury.

"A non-radioactive system such as our system could prove more efficient and less toxic than the current state of the art therapies, and much less toxic than traditional drugs, which can lead to many chemotherapy-associated complications," Farokhzad said.

The nanoparticles consisted of the anticancer drug docetaxel encapsulated within a safe, biodegradable polymer, to release the drug continually over time after the tumor absorbs the nanoparticles. The polymer is also effective against immediate removal from the body by the immune system, to help ensure the nanoparticles reached their intended target and do not inadvertently get absorbed by other cells beforehand.

The nanoparticles in turn were coated with RNA sequences known as aptamers, which can bind to specific cell surface receptors. In this case, the sequences targeted the prostate specific membrane antigen, a molecule that populate the surfaces of prostate cancer cells that is well known to get absorbed into the cell interior as well.

In mice, a single injection of the nanoparticles directly into prostate tumors resulted in complete tumor reduction in five of seven mice, with 100 percent surviving the entire 109-day study period. In contrast, nanoparticles without the RNA sequences resulted in complete tumor reduction in only two of seven mice and saw a 57 percent survival rate, while docetaxel treatment alone only had 14 percent survivability.

The Food and Drug Administration had approved the drug and polymers used in the nanoparticle therapy for prior clinical use, and the RNA aptamers are easy to synthesize and are not known to trigger immune responses, factors which the researchers hope could help quickly bring their nanoparticles for treatment in people.

"The route to FDA approval is a little easier if a new device or drug is based on materials that are already in use for other applications," said mechanical engineer David LaVan at Yale University in New Haven, Conn. "This does not mean that they can be used automatically, just that the approval path is shorter. It is good to see, as it is common for people to develop new materials like this with little awareness of what has been approved or not in the past."

Researcher Robert Langer, a chemical engineer chemical engineer at the Massachusetts Institute of Technology, added, "this technology could be applied to almost any disease" by re-engineering the nanoparticles' properties to make them target other cells and diseases. "The work could have widespread applications beyond prostate cancer through the use of specific aptamer-antigen combinations for other types of cancer," said biomedical engineer Jason Burdick University of Pennsylvania in Philadelphia.

Langer, Farokhzad and their colleagues reported their findings online Monday via the Proceedings of the National Academy of Sciences.

Copyright 2006 by United Press International

Explore further: Gold nanoparticle prostate cancer treatment found safe in dogs, study shows

Related Stories

Nanoparticles could provide easier route for cell therapy

June 24, 2014

UT Arlington physics researchers may have developed a way to use laser technology to deliver drug and gene therapy at the cellular level without damaging surrounding tissue. The method eventually could help patients suffering ...

Boosting immune therapy for cancer with nanoparticles

July 15, 2013

( —Activating the body's immune system to attack cancer and prevent it from recurring is one of the Holy Grails of cancer research because of its ability to specifically target cancer and to search almost anywhere ...

Recommended for you

Using optical fiber to generate a two-micron laser

October 9, 2015

Lasers with a wavelength of two microns could move the boundaries of surgery and molecule detection. Researchers at EPFL have managed to generate such lasers using a simple and inexpensive method.

Gene editing: Research spurs debate over promise vs. ethics

October 9, 2015

The hottest tool in biology has scientists using words like revolutionary as they describe the long-term potential: wiping out certain mosquitoes that carry malaria, treating genetic diseases like sickle-cell, preventing ...

ZomBee Watch helps scientists track honeybee killer

October 9, 2015

While scientists have documented cases of tiny flies infesting honeybees, causing the bees to lurch and stagger around like zombies before they die, researchers don't know the scope of the problem.

Ancient genome from Africa sequenced for the first time

October 8, 2015

The first ancient human genome from Africa to be sequenced has revealed that a wave of migration back into Africa from Western Eurasia around 3,000 years ago was up to twice as significant as previously thought, and affected ...

On soft ground? Tread lightly to stay fast

October 8, 2015

These findings, reported today, Friday 9th October, in the journal Bioinspiration & Biomechanics, offer a new insight into how animals respond to different terrain, and how robots can learn from them.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.