Therapeutic nanoparticles targeted to radiation treated tumors

March 28, 2011

Radiation and chemotherapy are common partners in anticancer therapy for solid tumors, but too often, the combined side effects associated with each mode of therapy can limit how aggressively oncologists can treat their patients. Now, a team of investigators from Vanderbilt University and Washington University in St. Louis, has developed a nanoparticle that only targets irradiated tumors, offering the potential for reducing chemotherapy-associated toxicities and increasing the effectiveness of combination therapy.

Radiation and are common partners in anticancer therapy for solid tumors, but too often, the combined side effects associated with each mode of therapy can limit how aggressively oncologists can treat their patients. Now, a team of investigators from Vanderbilt University and Washington University in St. Louis, has developed a nanoparticle that only targets irradiated tumors, offering the potential for reducing chemotherapy-associated toxicities and increasing the effectiveness of combination therapy.

Reporting its work in the Journal of Controlled Release, the team of investigators led by Zhoaozhong Han of Vanderbilt University describes how it used a technology known as "phase display" to identify a short peptide that binds specifically to irradiated tumor cells and used that peptide as an agent to target doxorubicin-containing nanoparticles to radiation-treated cells. Tests using cells grown in culture demonstrated that lipid-based nanoparticles decorated with this peptide do not bind to healthy cells, whether irradiated or not, nor to that are not irradiated.

To test if this targeting peptide exhibits the same selectivity in a living animal, the investigators dosed mice bearing human tumors with one of two lipid nanoparticles loaded with the anticancer drug : one nanoparticle was decorated with the targeting peptide, while the "control" nanoparticle was coated with a random peptide that showed no binding preference for a particular type of cell. The researchers also attached a fluorescent probe to the nanoparticles in order to track their accumulation in the animals. Each animal had tumors growing on both sides of the body, with the tumors on only one side receiving therapy.

When injected into the tumor-bearing mice, the targeted liposomes accumulated rapidly around the irradiated tumors but not around the tumors that were not irradiated. Similarly, the untargeted were largely excreted. More importantly, irradiated tumors treated with the targeted nanoparticle showed a marked increase in cell death and a substantial decrease in the number of blood vessels infusing those tumors. The researchers note that the use of anticancer targeted to irradiated tumors may make it possible to lower the dose of radiation used to treat tumors without negatively impacting therapeutic outcomes.

This work, which was supported in part by the National Cancer Institute, is detailed in a paper titled, "Tumor-targeted delivery of liposome-encapsulated doxorubicin by use of a peptide that selectively binds to irradiated tumors." An abstract of this paper is available at the journal's website.

Explore further: Polymer Nanoparticle Kills Tumors

Related Stories

Polymer Nanoparticle Kills Tumors

January 12, 2006

Photodynamic therapy (PDT), which uses a light-sensitive chemical known as a photosensitizer to produce cell-killing “reactive oxygen,” has become an important option for the treatment of esophageal cancer and non-small ...

Targeted Nanoparticles Destroy Prostate Tumors

April 25, 2006

Biodegradable polymer nanoparticles, linked to a protein-binding nucleic acid known as an aptamer and loaded with the anticancer agent docetaxel, can target and kill prostate tumors growing in mice. Using this targeted nanoparticle ...

Nanoparticles Overcome Anticancer Drug Resistance

June 12, 2006

Too often, chemotherapy fails to cure cancer because some tumor cells develop resistance to multiple anticancer drugs. In most cases, resistance develops when cancer cells begin expressing a protein, known as p-glycoprotein, ...

Multifunctional Nanoparticles Image and Treat Brain Tumors

December 4, 2006

Combining two promising approaches to diagnosing and treating cancer, a multidisciplinary research team at the University of Michigan has created a targeted multifunctional polymer nanoparticle that successfully images and ...

Nanoparticles Cooperate to Detect and Treat Tumors

March 26, 2010

(PhysOrg.com) -- If one nanoparticle is good, two may be better, especially when they are designed to cooperate with each other to diagnose and treat cancer. That finding comes from work led by Michael Sailor, Ph.D., a member ...

Image-guided breast cancer therapy enabled by nanodrug

October 28, 2010

By combining an iron oxide nanoparticle, a tumor-targeting peptide, and a therapeutic nucleic acid into one construct, a team of investigators from the Massachusetts General Hospital and Harvard Medical School have created ...

Recommended for you

Reshaping the solar spectrum to turn light to electricity

July 28, 2015

When it comes to installing solar cells, labor cost and the cost of the land to house them constitute the bulk of the expense. The solar cells—made often of silicon or cadmium telluride—rarely cost more than 20 percent ...

Meet the high-performance single-molecule diode

July 29, 2015

A team of researchers from Berkeley Lab and Columbia University has passed a major milestone in molecular electronics with the creation of the world's highest-performance single-molecule diode. Working at Berkeley Lab's Molecular ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.