Featured Research

from universities, journals, and other organizations

Stealth nanoparticles lower drug-resistant tumors' defenses

Date:
October 23, 2013
Source:
American Chemical Society
Summary:
Some of the most dangerous cancers are those that can outmaneuver the very drugs designed to defeat them, but researchers are now reporting a new Trojan-horse approach. In a preliminary study focusing on a type of breast cancer that is highly resistant to current therapies, they describe a way to sneak small particles into tumor cells, lower their defenses and attack them with drugs, potentially making the therapy much more effective.

A layered nanoparticle with an anticancer drug core, a gene-silencing inner layer and a tumor-targeting outer layer could provide a new way to attack drug-resistant cancer cells.
Credit: American Chemical Society

Some of the most dangerous cancers are those that can outmaneuver the very drugs designed to defeat them, but researchers are now reporting a new Trojan-horse approach. In a preliminary study in the journal ACS Nano focusing on a type of breast cancer that is highly resistant to current therapies, they describe a way to sneak small particles into tumor cells, lower their defenses and attack them with drugs, potentially making the therapy much more effective.

Paula T. Hammond and colleagues at the Koch Institute of Integrative Cancer Research at MIT note that triple-negative breast cancer (TNBC) is an aggressive disease that is difficult to treat with standard-of-care therapy, and patients' prognoses are poor. These cancer cells evade treatment by ramping up the production of certain proteins that protect tumors from chemotherapy drugs. Interfering with this process could give anticancer drugs a better chance at killing resistant tumors. Recent research into molecules called small interfering RNAs, or siRNAs, is opening doors into possible new treatments using this approach. These molecules can halt the production of particular proteins, so they are ideal candidates for dialing down the levels of protective proteins in tumors. But there are challenges to using siRNAs as part of a cancer therapy, so Hammond's team set out to address them with novel molecular engineering approaches.

They designed a two-stage, "stealth" drug delivery system to attack TNBC cells in mice, often used as stand-ins for humans in research. They created "layer-by-layer" nanoparticles through assembly of components in a certain order around a nano-sized core. An anticancer drug is loaded into the core of the particle, which is then wrapped in a layer of negatively charged siRNA, alternating with positively charged polypeptides, then coated on the outside with a stealthy tumor-targeting shell layer. That layer helps keep the particles in the body long enough for therapy to work. It also allows the particles to specifically bind to TNBC tumor cells. When tested in mice, the nanoparticles targeted the tumors and reduced the levels of protective proteins by nearly 80 percent. With the cancer cells rendered vulnerable, the nanoparticles' anticancer drug payload showed significantly enhanced therapeutic effects and shrunk tumors by 8-fold. The scientists state, "In summary, the results here provide a potential strategy to treat an aggressive and recurrent form of TNBC, as well as a means of adapting this platform to a broad range of controlled multi-drug therapies customizable to the cancer type in a singular nanoparticle delivery system." They also say that the "layer-by-layer" nanoparticle components are biocompatible and biodegradable, which will allow rapid translation into potential clinical benefits.


Story Source:

The above story is based on materials provided by American Chemical Society. Note: Materials may be edited for content and length.


Journal Reference:

  1. Zhou J. Deng, Stephen W. Morton, Elana Ben-Akiva, Erik C. Dreaden, Kevin E. Shopsowitz, Paula T. Hammond. Layer-by-Layer Nanoparticles for Systemic Codelivery of an Anticancer Drug and siRNA for Potential Triple-Negative Breast Cancer Treatment. ACS Nano, 2013; 131021120115007 DOI: 10.1021/nn4047925

Cite This Page:

American Chemical Society. "Stealth nanoparticles lower drug-resistant tumors' defenses." ScienceDaily. ScienceDaily, 23 October 2013. <www.sciencedaily.com/releases/2013/10/131023112634.htm>.
American Chemical Society. (2013, October 23). Stealth nanoparticles lower drug-resistant tumors' defenses. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2013/10/131023112634.htm
American Chemical Society. "Stealth nanoparticles lower drug-resistant tumors' defenses." ScienceDaily. www.sciencedaily.com/releases/2013/10/131023112634.htm (accessed July 31, 2014).

Share This




More Health & Medicine News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Concern Grows Over Worsening Ebola Crisis

Concern Grows Over Worsening Ebola Crisis

AFP (July 30, 2014) Pan-African airline ASKY has suspended all flights to and from the capitals of Liberia and Sierra Leone amid the worsening Ebola health crisis, which has so far caused 672 deaths in Guinea, Liberia and Sierra Leone. Duration: 00:43 Video provided by AFP
Powered by NewsLook.com
At Least 20 Chikungunya Cases in New Jersey

At Least 20 Chikungunya Cases in New Jersey

AP (July 30, 2014) At least 20 New Jersey residents have tested positive for chikungunya, a mosquito-borne virus that has spread through the Caribbean. (July 30) Video provided by AP
Powered by NewsLook.com
Xtreme Eating: Your Daily Caloric Intake All On One Plate

Xtreme Eating: Your Daily Caloric Intake All On One Plate

Newsy (July 30, 2014) The Center for Science in the Public Interest released its 2014 list of single meals with whopping calorie counts. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins