Tiny Particles Take Aim at Cancer Tumors

A drawing of CytImmune Sciences gold-based nanomedicine, Aurimune. Now in human clinical trials, Aurimune is a gold nanoparticle coated with an agent called tumor necrosis factor. The company believes the agent can weaken a tumor's blood vessels, making follow-up chemotherapy more effective.
A drawing of CytImmune Sciences gold-based nanomedicine, Aurimune. Now in human clinical trials, Aurimune is a gold nanoparticle coated with an agent called tumor necrosis factor. The company believes the agent can weaken a tumor's blood vessels, making follow-up chemotherapy more effective. (Cytimmune Science)
Tuesday, January 27, 2009

With the help of particles too small to be seen, cancer research may be taking giant leaps.

Researchers are trying to use nanoparticles (side by side, 100,000 of them are the width of a human hair) to target tumors more efficiently and safely.

"The big problem now is we have some very powerful drugs, but they affect the whole body," said Andrew Maynard, science adviser to the Project on Emerging Nanotechnologies, an initiative by Washington's Woodrow Wilson International Center for Scholars. "The way around that is to target the tumors directly, which nanoparticles can do."

CytImmune Sciences, a Rockville company, has developed a solid-gold nanoparticle, called Aurimune, that is coated with a tumor-weakening agent.

Because blood vessels around cancerous tumors are leaky, Aurimune nanoparticles can slip out of the vessels near a tumor and cluster around it.

If injected directly into the body, the agent, called tumor necrosis factor, would cause massive organ failure. But the nanoshells can be highly focused to aim for the tumor without affecting the rest of the body. The company believes the agent can weaken a tumor's blood vessels, making follow-up chemotherapy more effective.

Aurimune will enter its second phase of human trials at the National Institutes of Health this summer.

Robert Getzenberg, the director of urology research at the Johns Hopkins School of Medicine, has developed iron nanoparticles that attack prostate cancer tumors.

The iron nanoparticles warm up tumors to about 106 degrees -- essentially, giving the cancer a fever. The heated tumor reacts better to chemotherapy, Getzenberg said. His research is in animal trials.

And at Rice University, Jennifer West, a professor of bioengineering, has created gold nanoshells that cook the tumor to death.

It may take another decade for these treatments to be available to patients, but there are great hopes that they will revolutionize cancer treatment, Maynard said.

"The science shows that these treatments work," he said. "It's inescapable that we're going to see some very real progress in the years to come."

-- Sindya N. Bhanoo


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