Nanoparticles may enhance cancer therapy

A mixture of current drugs and carbon nanoparticles shows potential to enhance treatment for head-and-neck cancers, especially when combined with radiation therapy, according to new research by Rice University and the University of Texas MD Anderson Cancer Center.

The work blazes a path for further research into therapy customized to the needs of individual patients. The therapy uses carbon nanoparticles to encapsulate chemotherapeutic drugs and sequester them until they are delivered to the cancer cells they are meant to kill.

A paper on the research was published this month in the American Chemical Society journal ACS Nano.

The new strategy by Rice chemist James Tour and Jeffrey Myers, a professor of head-and-neck surgery at MD Anderson, combines paclitaxel (PTX) and Cetuximab (Cet) with hydrophilic carbon clusters functionalized with polyethylene glycol, known as PEG-HCC.

Cetuximab, the targeting agent, is a humanized monoclonal antibody that binds exclusively to the epidermal growth factor receptor (EGFR), a cell-surface receptor overexpressed by 90 percent of head-and-neck squamous cell cancers. Paclitaxel, an active agent in chemotherapy, is used to treat lung, ovarian, breast and head-and-neck cancers. In combination, they have the ability to target and attack cancerous cells.

Because paclitaxel is hydrophobic – it won't mix with water – the substances are generally combined with Cremophor EL, a castor oil-based carrier that allows the compound marketed as Taxol to be delivered intravenously to patients.

Tour, Myers and their associates have found a simple way to mix PTX and Cetuximab with carbon clusters that adsorb the active ingredients. The new compound is water-soluble and is more effective at targeting tumors than Taxol while avoiding the toxic effects of paclitaxel and Cremophor on adjacent healthy cells, they wrote.

Magnetic nanoparticles target human cancer cells Georgia Tech scientists follow up their 2008 study on mice with findings that these nanoparticles target and attach themselves to human cancer cells just as effectively, then remove them from the body. In 2008, scientists at the Georgia Institute of Technology and the Ovarian Cancer Institute developed a potential treatment to fight cancer using magnetic nanoparticles designed to attach themselves to cancer cells. They found in their groundbreaking tests on mice that the particles not only attached to cancer cells, but they also moved those cells.

In what may well prove to be some of the most exciting health news in the year to come, the group announced in the journal Nanomedicine in December and further publicized on Tuesday that it has replicated the study on human cancer cells, with the nanoparticles appearing to be every bit as effective.
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Elizabeth Armstrong Moore