Researchers have found a way to target cancer cells by injecting tiny particles that will attack only the diseased cells while leaving healthy cells unscathed, according to a study released on Monday.
A team of researchers working at MIT and Brigham and Women’s Hospital in Boston laced tiny particles with lethal doses of chemotherapy and when injected they targeted cancer cells alone.
The team first conducted experiments on cells growing in laboratory dishes and then on mice bearing human prostate tumors, according to the study, published in the online edition of the Proceedings of the National Academy of Sciences.
In the mice, the tumors shrank dramatically and all of the mice survived the study while the untreated control animals did not.
“A single injection of our nanoparticles completely eradicated the tumors in five of the seven treated animals, and the remaining animals also had a significant tumor reduction, compared to the controls,” said Dr. Omid Farokhzad, assistant professor at Brigham and Women’s Hospital and Harvard Medical School.
While all the parts of this new delivery system are known to be safe, it must still be proven safe for humans. The scientists said that further testing is needed on larger animals, and eventually in humans.
Potential health hazards
Some reports have suggested that nanoparticles might cause damage to cells and be hazardous to health because of their tiny size, and some experts advocate more research before they come into wide use.
According to the study, the researchers tailor-made tiny sponge-like nanoparticles laced with the drug docetaxel. The particles are designed to dissolve in a cells’ internal fluids, releasing the anti-cancer drug either rapidly or slowly, depending on what is needed.
To make sure that only the correct cells are hit, the nanoparticles are “decorated” on the outside with targeting molecules called aptamers, or tiny chunks of genetic material.
Like homing devices, the aptamers specifically recognize the surface molecules on cancer cells, while avoiding normal cells.
The team chose nanoparticles as drug-delivery vehicles because they are so small that living cells will readily swallow them when at the cell’s surface.