News | July 29, 2009

Johns Hopkins Researchers Use Nanoparticles to Carry Cancer-Treating Radioisotopes

July 29, 2009 - A group of researchers at Johns Hopkins University has designed nanoparticles that can carry cancer-treating radioisotopes through the body and deliver them selectively to tumors. Today in Anaheim, CA, they will report the latest results of their research, including studies in animal models, at the 51st meeting of the American Association of Physicists in Medicine (AAPM).

The nanoparticles are made with a commercially available product known as "liposomes" - small chemical spheres made of fatty molecules that can package drugs and other chemicals. Liposomes are a powerful emerging tool in medicine because they can be designed to carry many different drugs and manipulated to control how long they stay in the bloodstream. One type of liposome, Doxil, is already approved by the U.S. Food and Drug Administration (FDA) for delivering Doxorubicin, a chemotherapeutic that is toxic to the heart.

In their talk on Tuesday, "Immunoliposomes for Targeted Radionuclide Therapy," the Hopkins scientists explained how they are using liposomes that have been modified with antibodies, a class of immune system proteins that recognize and bind to many different microscopic targets - bacteria, viruses, other proteins, and human cells. Some antibodies specifically bind to cancer cells, and by attaching these cancer-specific antibodies to the liposomes, the scientists have created "immunoliposomes," which will wend their way through the bloodstream and seek out tumors inside the body. When they come into contact with their target cells, they deliver their payload into the cells.

"It's a promising approach to solving the problem of how to deliver more of a therapeutic to cancer cells," said George Sgouros, a radiology professor at Johns Hopkins who led the research.

Similar studies by other groups of researchers have already demonstrated how immunoliposomes could be packaged with tiny radioactive tracers used for imaging tumors. What Sgouros and his colleagues have done is figure out how to reproducibly package much more powerful radioisotopes, called alpha-particle emitters that have the ability to kill cancer cells without damaging nearby normal cells, and they have tested how effectively they can treat mice with a very aggressive type of metastatic breast cancer.

Early results show that they can pack a relatively large dose of radionuclides into the liposomes and substantially extend the life of treated mice.

"This treatment is much less toxic than chemotherapy because it is targeted to tumor cells rather than to all rapidly dividing cells," said Sgouros. "Nanoparticles designed to deliver these powerful isotopes have a great potential in cancer therapy, particularly for metastatic disease."

For more information: www.aapm.org/meetings/09AM/PRAbs.asp?mid=42&aid=11894

Related Content

PET Imaging Agent Predicts Brain Tau Pathology, Alzheimer's Diagnosis
News | PET Imaging | September 05, 2018
Eli Lilly and Co. and Avid Radiopharmaceuticals Inc. announced a Phase 3 study of positron emission tomography (PET)...
Abnormal Protein Concentrations Found in Brains of Military Personnel With Suspected CTE

Researchers are using the tracer, which is injected into a patient, then seen with a PET scan, to see if it is possible to diagnose chronic traumatic encephalopathy in living patients. In this image, warmer colors indicate a higher concentration of the tracer, which binds to abnormal proteins in the brain. Credit UCLA Health.

News | PET Imaging | August 24, 2018
August 24, 2018 — In a small study of
PET/CT Changes Care for 59 Percent of Suspected Recurrent Prostate Cancer Cases
News | Prostate Cancer | June 13, 2018
A recently presented investigational clinical trial evaluated the impact of 18F fluciclovine positron emission...
PET Imaging Agent Could Provide Early Diagnosis of Rheumatoid Arthritis

Coronal 18F-FEDAC PET/CT section of a mouse with collagen-induced arthritis. (A) On day 23 and day 37, increased uptake is noted in the front and hind paws of this mouse with collagen-induced arthritis. (B) Predictive performance of day 23 18F-FEDAC uptake for the development of clinical arthritis. ROC = receiver operating characteristic; Sn = sensitivity; Sp = specificity. Credit: Seoul National University and Ewha Womans University, Seoul, South Korea

News | PET Imaging | May 17, 2018
A novel positron emission tomography (PET) tracer developed by Korean researchers can visualize joint inflammation and...
News | Radiopharmaceuticals and Tracers | May 09, 2018
Blue Earth Diagnostics signed an exclusive, worldwide agreement with Scintomics GmbH, Germany, a specialist in...
Novel PET Agent Could Help Guide Therapy for Brain Diseases

Rat brain 11C‐Me‐NB1 PET images (0‐60 min) superimposed on an MRI template. Credit: SD Krämer et al., ETH Zurich, Zurich, Switzerland

News | PET Imaging | April 10, 2018
Researchers have developed a new imaging agent that could help guide and assess treatments for people with various...
The Chalk River nuclear reactor license has been renewed, but will be decommissioned by 2028.

The Chalk River nuclear isotope reactor license has been renewed, but will be decommissioned by 2028. The reactor supplies about 50 percent of the world's supply of Tc99m.

Feature | Nuclear Imaging | April 02, 2018 | Dave Fornell
April 2, 2018 – The Canadian Nuclear Safety Commission (CNSC) announced March 29 that it renewed Canadian Nuclear Lab
Axumin PET Agent Added to NCCN Guidelines for Suspected Recurrent Prostate Cancer
News | PET Imaging | February 21, 2018
Blue Earth Diagnostics announced that Axumin (fluciclovine F 18) injection has been added to the National Comprehensive...
A Tc99m SPECT cardiac exam showing myocardial perfusion in the heart.

Technetium-99m is primarily used for the detection of cancer and to assess perfusion defects in the heart caused by heart attacks or other conditions.

Feature | Radiopharmaceuticals and Tracers | February 08, 2018 | Dave Fornell
February 8, 2018 — The U.S.