Nanotechnology holds hope for targeting of cancer cells

Applying nanotechnology with laser therapy may offer hope for treating cancer in hard-to-reach and highly risky areas.

Researchers at Wake Forest University Baptist Medical Center are using carbon nanotubes — threads of hollow carbon that are 10,000 times thinner than a human hair — to target tumors.

The researchers demonstrated their latest developments last week before the American Association of Physicists in Medicine. They have been working on the technology for four years.

Right now, the procedure is limited to treating tumors in mice, said David Carroll, the director of the university’s Center for Nanotechnology and Molecular Materials.

“It’s a few years away from use in humans, but we believe we offer the most promising methods for treating cancer with this technology,” Carroll said.

The use of laser technology in cancer treatment has been around for decades.

According to the National Cancer Institute, the most common uses of laser therapy is treating cancers on the surface of the body or the lining of internal organs. Lasers also may be used to relieve certain symptoms of cancer, such as bleeding or obstruction, or to remove colon polyps or tumors that are blocking the colon or stomach.

A primary reason for the limited success with laser therapy is the challenge of fine-tuning the laser well enough to prevent collateral damage to healthy tissue. That’s critical when trying to eliminate tumors in high-risk areas, such as the brain, heart and lungs.

What makes the Wake Forest Baptist approach different is the focus on certain nanoparticles that can absorb the energy of a laser and convert it into heat.

“If the nanoparticles are zapped while within a tumor, they will boil off the energy as heat and kill the cancerous cells,” according to the researchers.

Where the nanotubes come into play is that by inserting iron into them, the nanoparticles become visible to an MRI scanner.

“We can measure the temperature and the amount of heat that is applied from the laser without having to open up the patient,” Carroll said. “That way, we can tailor the treatment to the individual patient.”

Finding the exact location of the nanoparticle in the human body is very important to the treatment, said Xuanfeng Ding, one of the Wake Forest Baptist researchers. “It is really exciting to watch the tumor labeled with the nanotubes begin to shrink after the treatment,” he said.

A previous study by the researchers found that laser-induced thermal therapy using a nanoparticle increased the long-term survival of mice with tumors.

The next step in the current study is determining whether the iron-loaded nanoparticles can do the same thing, Carroll said.

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