Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Dual-Purpose Nanoparticles Spot Residual Tumors, Improves Cancer Surgery

Abstract:
The surest cure for cancer is to remove every last bit of a tumor through surgery. Unfortunately, for most cancers that is also the most difficult approach because of two problems: it is nearly impossible today to spot every last tumor in the body and it is often difficult to determine where a tumor stops and healthy tissue begins. A solution to both of those problems may be at hand in the form of a dual-purpose nanoparticle that penetrates tumor cells and lights them up using either fluorescence imaging or magnetic resonance imaging (MRI).

Dual-Purpose Nanoparticles Spot Residual Tumors, Improves Cancer Surgery

Bethesda, MD | Posted on March 22nd, 2010

A team of investigators led by Roger Tsien, Ph.D., a member of the National Cancer Institute-funded Center of Nanotechnology for Treatment, Understanding, and Monitoring of Cancer at the University of California, San Diego, developed a dual-purpose nanoparticle that only enters cells coated with two proteins that tumor cells use to invade healthy tissue. Once the nanoparticles accumulate in tumor cells, they become readily visible using either MRI or a standard fluorescence microscope. The researchers report that they can spot tumors as small as 200 microns in diameter, and that they can then remove even microscopic traces of malignant tissue by tracking the fluorescent signal the nanoparticles emit. Dr. Tsien and his colleagues report their work in back-to-back papers appearing in the Proceedings of the National Academy of Sciences.

The investigators built their probe using a spherical polymeric nanoparticle known as a dendrimer. Dendrimers have numerous chemical linkages available on their surface, which enabled Dr. Tsien's team to attach three different entities to each nanoparticle: an activatable cell penetrating peptide (ACPP); three molecules of the brightly fluorescent dye known as Cy5; and 15-30 molecules of gadolinium chelate, a potent MRI contrast agent, to each nanoparticle.

ACPPs are short, positively charged peptides linked by a cleavable molecule to a second negatively charged peptide. Positively charged peptides are well-known for their ability to penetrate cells, but in the inactivated state the linked negatively charged peptide blocks cell penetration. Cleaving the linker removes the negatively charged peptide, allowing the remaining positively charge peptide - and any attached cargo - to enter cells. In this case, the linker is cleaved only by one of two proteins - matrix metalloprotein-2 or matrix metalloprotein-9 - that are present in large numbers on the surfaces of tumor cells. As a result of this specificity, nanoparticles attached to this ACPP only enter tumor cells. Nanoparticles attached to a similar peptide, but one that cannot be cleaved, did not enter tumor cells and were cleared rapidly from the body.

When injected into animals bearing human tumors, the nanoparticles accumulated in tumors over 48 hours and were readily visible using whole body MRI. When the investigators were conducting this experiment, they noticed bright edges surrounding even small tumors. Upon closer examination using fluorescence microscopy, the researchers were able to clearly delineate the jagged edges of tumors.

Using the bright fluorescent edges as a guide, the investigators were then able to achieve more complete tumor removal than was possible without nanoparticle guidance. Tumor-bearing mice who received the nanoparticles prior to surgery had better long-term tumor-free survival and overall survival than did animals whose tumors were removed using traditional bright-light illumination. The investigators were documented using followup MRI that they had removed all tumors during surgery.

This work is detailed in two papers. The first is titled, "Activatable cell penetrating peptides linked to nanoparticles as dual probes for in vivo fluorescence and MR imaging of proteases," and the second it titled, "Surgery with molecular fluorescence imaging using activatable cell-penetrating peptides decreases residual cancer and improves survival." Abstracts of these papers are available at the journal's Web site.

View abstract 1: www.pnas.org/content/107/9/4311
View abstract 2: dx.doi.org/10.1073/pnas.0910261107

####

About NCI Alliance for Nanotechnology in Cancer
To help meet the goal of reducing the burden of cancer, the National Cancer Institute (NCI), part of the National Institutes of Health, is engaged in efforts to harness the power of nanotechnology to radically change the way we diagnose, treat and prevent cancer.

The NCI Alliance for Nanotechnology in Cancer is a comprehensive, systematized initiative encompassing the public and private sectors, designed to accelerate the application of the best capabilities of nanotechnology to cancer.

Currently, scientists are limited in their ability to turn promising molecular discoveries into benefits for cancer patients. Nanotechnology can provide the technical power and tools that will enable those developing new diagnostics, therapeutics, and preventives to keep pace with today’s explosion in knowledge.

For more information, please click here

Copyright © NCI Alliance for Nanotechnology in Cancer

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

No need in supercomputers: Russian scientists suggest a PC to solve complex problems tens of times faster than with massive supercomputers June 30th, 2016

Surprising qualities of insulator ring surfaces: Surface phenomena in ring-shaped topological insulators are just as controllable as those in spheres made of the same material June 30th, 2016

How cancer cells spread and squeeze through tiny blood vessels (video) June 30th, 2016

Possible Futures

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

No need in supercomputers: Russian scientists suggest a PC to solve complex problems tens of times faster than with massive supercomputers June 30th, 2016

Surprising qualities of insulator ring surfaces: Surface phenomena in ring-shaped topological insulators are just as controllable as those in spheres made of the same material June 30th, 2016

Building a smart cardiac patch: 'Bionic' cardiac patch could one day monitor and respond to cardiac problems June 28th, 2016

Academic/Education

JPK’s NanoWizard® AFM and ForceRobot® systems are being used in the field of medical diagnostics in the Supersensitive Molecular Layer Laboratory of POSTECH in Korea June 21st, 2016

Weizmann Institute of Science Presents: Weizmann Wonder Wander - 4G - is Online June 21st, 2016

NanoLabNL boosts quality of research facilities as Dutch Toekomstfonds invests firmly June 10th, 2016

The Institute for Transfusion Medicine at the University Hospital of Duisburg-Essen in Germany uses the ZetaView from Particle Metrix to quantify extracellular vesicles June 7th, 2016

Nanomedicine

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

How cancer cells spread and squeeze through tiny blood vessels (video) June 30th, 2016

Building a smart cardiac patch: 'Bionic' cardiac patch could one day monitor and respond to cardiac problems June 28th, 2016

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Announcements

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

No need in supercomputers: Russian scientists suggest a PC to solve complex problems tens of times faster than with massive supercomputers June 30th, 2016

Surprising qualities of insulator ring surfaces: Surface phenomena in ring-shaped topological insulators are just as controllable as those in spheres made of the same material June 30th, 2016

How cancer cells spread and squeeze through tiny blood vessels (video) June 30th, 2016

Nanobiotechnology

A drop of water as a model for the interplay of adhesion and stiction June 30th, 2016

How cancer cells spread and squeeze through tiny blood vessels (video) June 30th, 2016

Building a smart cardiac patch: 'Bionic' cardiac patch could one day monitor and respond to cardiac problems June 28th, 2016

Nanotechnology and math deliver two-in-one punch for cancer therapy resistance June 24th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic