Nanotech The Talk of Cancer Symposium
By ExtremeTech Staff
November 23, 2005
Nanotechnology was the subject of much conversation at the American Association for Cancer Research conference in Philadelphia recently. At a press conference called Advances in Nanotechnology for Cancer Diagnostics and Treatment, four major projects were discussed in detail.
The first involved the use of tiny carbon nanotubes and monoclonal antibodies to detect cancer cells in the laboratory dish. Researchers at the University of Delaware coated the surface of microscopic carbon nanotubes with a monoclonal antibody that sought out insulin-like growth factor 1 receptor (IGF1R), a protein commonly found on cancer cells.
The nanotubes then homed in on the cancer cells like a heat-seeking missile. When cancer cells and antibodies bind together, there is a measurable change in electric current. The hope is that these nanotubes will allow for spotting circulating cancer cells in the blood from a new cancer or from a treated tumor that has returned at a very early stage, when it is more treatable.
Researchers at Rice University have put together two technologies that are harmless by themselves, but in tandem have potent cancer-killing properties. They combined "nanoshells," microscopic balls consisting of a silica core coated with a thin layer of gold with near infrared light (NIR). NIR is light just beyond the red wavelength, thus invisible to the human eye.
Neither of these two have any ill effects on the body. Together, however, the NIR heats up the gold shell, which causes the particles to destroy tumor cells. The nanoshells tended to gravitate toward tumors because blood vessels that develop in fast-growing solid tumors are poorly formed and permeable, so the nanoshells were able to penetrate the arterial wall to the tumor.
The third project involved scientists at the Pennington Biomedical Research Center in Baton Rouge, LA treating breast cancer. In this test, a nanoparticle was combined with a cancer-killing drug, Hecate and a hormone found in breast cancer cells with an abundance of receptors.
Tests found that the drug was most effective when it came in direct contact with the cell membrane, and it took the hormone to make that connection. Tests will continue, trying to make the compound more efficient and use less of the drug.
Finally, researchers at Georgetown University Medical Center's Lombardi Comprehensive Cancer Center created a liposome nanoparticle with antibodies covering the surface that can home in on tumor cells anywhere in the body. The liposome encapsulates the p53 gene, which makes a protein that helps initiate a self-destruct process called apoptosis in cells with genetic damage.
Since cancer cells are by their nature defective, this makes cancer cells self-destruct and leaves healthy cells alone. More than one-half of cancers have mutations in the p53 gene, which has been called the "guardian of the genome" because of its ability to get rid of genetically-damaged cells. |
