July 29, 2009

Scientists Test New Way to Get Drugs to Cancer Cells

WEDNESDAY, July 29 (HealthDay News) -- Nanoparticles that can carry cancer-killing radioisotopes directly to tumors show promise, U.S. researchers report.

The nanoparticles are made with liposomes, small chemical spheres made of fatty molecules that can be designed to carry a number of drugs and chemicals, and can be manipulated to control how long they remain in the bloodstream.

Johns Hopkins University researchers attached cancer-specific antibodies to liposomes to create immunoliposomes that travel through the bloodstream and seek out tumors. When they come in contact with tumors, the immunoliposomes deliver their payload into cancer cells.

"It's a promising approach to solving the problem of how to deliver more of a therapeutic to cancer cells," research leader and radiology professor George Sgouros said in a news release from the American Association of Physicists in Medicine.

The research was to be presented July 28 at the association's annual meeting, in Anaheim, Calif.

In a study on mice, Sgouros and his colleagues loaded the immunoliposomes with alpha-particle emitters, which are powerful radioisotopes that can kill cancer cells without damaging nearby healthy cells. The treatment substantially extended the survival of mice that had aggressive metastatic breast cancer.

"This treatment is much less toxic than chemotherapy because it is targeted to tumor cells rather than to all rapidly dividing cells," Sgouros said. "Nanoparticles designed to deliver these powerful isotopes have a great potential in cancer therapy, particularly for metastatic disease."

More information

The U.S. Food and Drug Administration has more about nanotechnology.

-- Robert Preidt
SOURCE: American Association of Physicists in Medicine, news release, July 28, 2009
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