Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nanoparticles offer new hope for detection and treatment

25.04.2005


The nanoparticles shown here are irregularly shaped due to the fixing process for electron microscopes. They are normally perfect spheres.


The top image shows an MRI of a melanoma tumor without nanoparticles. The bottom one shows the same tumor lighted up by nanoparticles.


Particles could make earlier cancer diagnosis possible

Specially designed nanoparticles can reveal tiny cancerous tumors that are invisible by ordinary means of detection, according to a study by researchers at Washington University School of Medicine in St. Louis.

The researchers demonstrated that very small human melanoma tumors growing in mice—indiscernible from the surrounding tissue by direct MRI scan—could be "lit up" and easily located as soon as 30 minutes after the mice were injected with the nanoparticles.



Because nanoparticles can be engineered to carry a variety of substances, they also may be able to deliver cancer-fighting drugs to malignant tumors as effectively as they carry the imaging materials that spotlight cancerous growth. "One of the best advantages of the particles is that we designed them to detect tumors using the same MRI equipment that is in standard use for heart or brain scans," says senior author Gregory Lanza, M.D., Ph.D., associate professor of medicine. "We believe the technology is very close to being useful in a hospital setting."

Lanza and his colleague Samuel Wickline, M.D., professor of medicine, are co-inventors of this nanoparticle technology. The effectiveness of the nanoparticles in diagnosis and therapy in humans will be tested in clinical trials in about one and a half to two years. The spherical nanoparticles are a few thousand times smaller than the dot above this "i," yet each can carry about 100,000 molecules of the metal used to provide contrast in MRI images. This creates a high density of contrast agent, and when the particles bind to a specific area, that site glows brightly in MRI scans.

In this study, MRI scans picked up tumors that were only a couple of millimeters (about one twenty-fifth of an inch) wide. Small, rapidly growing tumors cause growth of new blood vessels, which feed the tumors. To get the particles to bind to tumors, the researchers equipped them with tiny "hooks" that link only to complementary "loops" found on cells in newly forming blood vessels. When the nanoparticles hooked the "loops" on the new vessels’ cells, they revealed the location of the tumors. Nanoparticles are particularly useful because of their adaptability, according to Lanza, who sees patients at Barnes Jewish Hospital. "We can also make these particles so that they can be seen with nuclear imaging, CT scanning and ultrasound imaging," Lanza says.

In addition, the particles can be loaded with a wide variety of drugs that will then be directed to growing tumors. "When drug-bearing nanoparticles also contain an imaging agent, you can get a visible signal that allows you to measure how much medication got to the tumor," Lanza says. "You would know the same day you treated the patient and if the drug was at a therapeutic level." Using nanoparticles, drug doses could be much smaller than doses typically used in chemotherapy, making the procedure potentially much safer. "The other side of that is you have the ability to focus more drug at the tumor site, so the dose at the site might be ten to a thousand times higher than if you had administered the drug systemically," Lanza says.

The nanoparticles also may permit more effective follow up, because a doctor could use them to discern whether a tumor was still growing after radiation or chemotherapy treatments. Although this study focused on melanoma tumors, the researchers believe the technology should work for most solid tumors, because all tumors must recruit new blood vessels to obtain nutrients as they grow. Nevertheless, melanoma has unique traits that make it especially interesting as a target for nanoparticle therapy. Melanoma has a horizontal phase, when it spreads across the skin surface, and a vertical phase, when it goes deep into the body and grows quickly. "Once melanoma has moved into its vertical phase, it is almost untreatable because by the time the tumors are large enough to detect, it’s too late," Lanza says. "With the nanoparticles, we believe we would be able to see the smallest melanoma tumors when they are just large enough to begin new blood vessel formation. Plus, we should be able to deliver chemotherapeutic drugs right to melanoma cells, because melanoma tumors create blood vessels using their own cells."

Jim Dryden | EurekAlert!
Further information:
http://www.wustl.edu

More articles from Health and Medicine:

nachricht Researchers identify cause of hereditary skeletal muscle disorder
22.02.2017 | Klinikum der Universität München

nachricht Second cause of hidden hearing loss identified
20.02.2017 | Michigan Medicine - University of Michigan

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>