Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > Enabling Nanoparticles to Penetrate Deeply in Tumors

Abstract:
Too often, researchers designing nanoparticles capable of delivering effective doses of anticancer agents to tumors must balance the need to choose a nanoparticle that is small enough to escape the leaky blood vessels that surround tumors but large enough to avoid rapid clearance from the blood stream via the kidneys. Balancing these two requirements usually results in using nanoparticles that are indeed small enough to accumulate in the vicinity of tumors, but that are really too large to penetrate deeply enough into tumors to have the maximum therapeutic effect.

Enabling Nanoparticles to Penetrate Deeply in Tumors

Bethesda, MD | Posted on February 23rd, 2011

Now, a large team of researchers from the Massachusetts Institute of Technology, Massachusetts General Hospital, and Harvard Medical School have developed a solution to this problem: multilayered, or multistage, nanoparticles that partially dissolve once they accumulate around tumors, leaving behind a payload of nanoparticles a mere one-tenth the size of the original delivery vehicle. The remaining 10-nanometer-diameter nanoparticles, loaded with anticancer drugs, can then diffuse deeply into a tumor's dense interior.

Dai Fukumura, Moungi Bawendi, and Rakesh Jain, all senior faculty members at their respective institutions, directed this study. The team published their results in the Proceedings of the National Academy of Sciences. Dr. Bawendi is also a member of the MIT-Harvard Center for Cancer Nanotechnology Excellence funded by the National Cancer Institute.

The key to the new nanoparticles is a gelatin material that can serve as a substrate for enzymes that are produced at high levels by tumors. Cancer cells use these enzymes to dissolve the extracellular matrix that surrounds organs, enabling these malignant cells to escape into the bloodstream and colonize sites distant from the primary tumor. The researchers took advantage of this enzyme by embedding tiny nanoparticles within the gelatin core of the larger nanoparticles that they designed to be injected into the blood stream.

For this set of experiments, the investigators loaded 100-nanometer the gelatin nanoparticles with 10-nanometer quantum dots. While quantum dots are not likely to be used to deliver drugs to tumors, these nanobeacons produce bright optical signals that can be easily monitored as they are released from the larger nanoparticles. Initial experiments using tumors growing in culture showed that the gelatin-degrading enzymes did their job and that the released quantum dots were able to diffuse farther and more efficiently than the 100 nanometer particles into the tumors. Subsequent experiments in tumor-bearing mice confirmed these in vitro findings, and as a result, the investigators are now planning to repeat these experiments using drug loaded 10-nanometer particles in place of the quantum dots they used in this study.

Another approach to getting nanoparticles deep into tumors is to disrupt a tumor's ability to form the dense extracellular matrix, made of the protein collagen, that keeps nanoparticles in the outer regions of a tumor. Dr. Jain's group at MIT and the Harvard Medical School have done just that, using the widely used high-blood pressure medication Losartan to inhibit collagen synthesis. The investigators also published the results of these studies in the Proceedings of the National Academy of Sciences.

Human clinical studies have shown that Losartan reduces the incidence of cardiac and renal fibrosis by reducing the synthesis of one particular form of collagen, known as type I. Dr. Jain and his colleagues reasoned that this same inhibitory effect might lead to easier passage of nanoparticles into the deep recesses of a tumor. In fact, that is exactly the effect they observed at doses of the drug that were small enough to leave blood pressure unaffected. Tests showed that Doxil, the first approved nanoparticulate anticancer agent, was more effective at treating dense, fibrotic tumors, such as pancreatic tumors, growing in mice. Dr. Jain and his colleagues note in their paper that because long-term Losartan therapy has proven safe in humans, and because many anticancer agents raise blood pressure, administering Losartan with nanoparticles has the strong possibility of benefitting cancer patients.

####

About The National Cancer Institute (NCI)
The NCI Alliance for Nanotechnology in Cancer is engaged in efforts to harness the power of nanotechnology to radically change the way we diagnose, treat, and prevent cancer. Through its programs and initiatives, the Alliance is committed to building a community of researchers dedicated to using nanotechnology to advance the fight against cancer.

As part of the Center for Strategic Scientific Initiatives, the Alliance for Nanotechnology in Cancer works in concert with other NCI advanced technology initiatives to provide the scientific foundation and team science that is required to transform cancer research and care.

For more information, please click here

Contacts:
National Cancer Institute
Center for Strategic Scientific Initiatives
NCI Office of Cancer Nanotechnology Research (OCNR)
Building 31, Room 10A52
31 Center Drive, MSC 2580
Bethesda, MD 20892-2580
Telephone: (301) 451-8983

Copyright © The National Cancer Institute (NCI)

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 Links

View abstract - "Multistage nanoparticle delivery system for deep penetration into tumor tissue."

View abstract - "Losartan inhibits collagen I synthesis and improves the distribution and efficiency of nanotherapeutics in tumors."

Related News Press

News and information

MTU engineers examine lithium battery defects January 28th, 2020

Extraction of lithium from its largest source, i.e. seawater, by nanostructured membranes January 27th, 2020

SUNY Poly Professor Partners with Leading Institutions on NSF Award for Quantum Information Science Research: SUNY Poly Research Builds Upon Recent Quantum-related Research Initiatives and Workshops January 27th, 2020

What if the Universe has no end? The Big Bang is widely accepted as being the beginning of everything we see around us, but other theories that are gathering support among scientists are suggesting otherwise January 25th, 2020

Nanotubes/Buckyballs/Fullerenes/Nanorods

The first highway trials show that nanotube-reinforced asphalt concrete prevents cracks and ruts January 16th, 2020

A new approach to making airplane parts, minus the massive infrastructure: Carbon nanotube film produces aerospace-grade composites with no need for huge ovens or autoclaves. January 13th, 2020

Color superlensing to assist in surpassing diffraction barrier: A paper by Kazan Federal University's Sergey Kharintsev appeared in Optics Letters January 3rd, 2020

Buckyballs release electron-positron pairs in forward directions: Theoretical calculations reveal that when impacted by positrons of particular energies, spherical nanoparticles release unstable electron-positron pairs, with signals dominating in the same direction as the incomin December 27th, 2019

Nanomedicine

Arrowhead Pharmaceuticals to Webcast Fiscal 2020 First Quarter Results January 24th, 2020

International Summit on Nanomedicine & Nanotechnology January 24th, 2020

How to keep boron inside cells during radiotherapy: a simple novel approach to cancer treatment January 24th, 2020

Nanomaterial fabric destroys nerve agents in battlefield-relevant conditions: Metal-organic framework-based composites donít need liquid water to work January 14th, 2020

Discoveries

Extraction of lithium from its largest source, i.e. seawater, by nanostructured membranes January 27th, 2020

Quantum physics: On the way to quantum networks January 24th, 2020

Nano-thin flexible touchscreens could be printed like newspaper: New touch-responsive technology is 100 times thinner than existing touchscreen materials and so pliable it can be rolled up like a tube January 24th, 2020

Old Molecule, New Tricks: Chemistry professors develop an electrochemical method for extracting uranium, and potentially other metal ions, from solution January 24th, 2020

Announcements

MTU engineers examine lithium battery defects January 28th, 2020

Extraction of lithium from its largest source, i.e. seawater, by nanostructured membranes January 27th, 2020

SUNY Poly Professor Partners with Leading Institutions on NSF Award for Quantum Information Science Research: SUNY Poly Research Builds Upon Recent Quantum-related Research Initiatives and Workshops January 27th, 2020

American Chemical Society names Philip Proteau as new editor-in-chief of the Journal of Natural Products January 24th, 2020

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



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project