Nano, Nano, Nano

Justine Cadet, Executive Editor

Preclinical research with nanoparticle imaging has shown true potential for cancer detection because nanoparticles have the potential to illuminate the cellular interior to reveal complex processes in a living cell. This has lead to an explosion of preclinical studies involving nanoparticles for various cancers.

Unlike the traditional organic fluorescent probes, fluorescent nanoparticle probes such as dye-doped nanoparticles and quantum dots are bright and photostable. Fluorescent nanoparticle probes are shown to be very effective for sensitive cancer imaging with greater success in the cellular level (Technol Cancer Res Treat 2005;4(6):593-602).

Two studies in this month’s preclinical imaging issue demonstrate the effectiveness of the new technology.

First, Shaoli Song, MD, of the University of Texas M.D. Anderson Cancer Center in Houston, and colleagues used nine mice bearing subcutaneous human mammary BT474 tumors. They injected five mice intratumorally with semiconductor CuS nanoparticles, followed by near-infrared laser irradiation 24 hours later (12 W/cm2 for three minutes), and four mice were not treated (control group).

The purpose of this study was to investigate the potential application of small-molecular-weight 64Cu-labeled bis-DOTA-hypericin in the noninvasive assessment of response to photothermal ablation therapy. Using this strategy, the researchers found that 64Cu-bis-DOTA-hypericin has potential to image thermal therapy-induced tumor cell damage.

Next, researchers showed that a class of engineered nanoparticles—Raman-silica-gold-nanoparticles—has been shown to be safe when administered by two alternative routes in mouse models, which marks the first step up the ladder of toxicology studies that, within a year and a half, could yield to human trials of these agents for detection of colorectal and possibly other cancers, according researchers from Stanford University School of Medicine in Stanford, Calif.

"These nanoparticles' lack of toxicity in mice is a good sign that they'll behave well in humans," said the study’s lead author Sanjiv Sam Gambhir, MD, PhD, professor of radiology at Stanford University School of Medicine. "Early detection of any cancer, including colorectal cancer, markedly improves survival.”

Please let us know of such ongoing nanoparticle research at your facilities.

Justine Cadet
jcadet@trimedmedia.com