Featured Research

from universities, journals, and other organizations

Nanoparticles shrink tumors in mice

Date:
July 11, 2010
Source:
University of California - Los Angeles
Summary:
A new study demonstrates that nanoparticles can store and deliver chemotherapeutic drugs in vivo and effectively suppress tumors in mice. Strikingly, these nanoparticles accumulate in tumor after administration. Furthermore, the researchers showed that these nanoparticles are completely excreted from the body. The findings show promise for further uses of nanoparticles for delivery of chemotherapeutic drugs for cancer therapy.

A dorsal view of a mouse showing accumulation of nanoparticles in a tumor four hours after intravenous administration. Bright fluorescence is observed predominantly in the tumor.
Credit: Image courtesy of University of California - Los Angeles

The application of nanotechnology in the field of drug delivery has attracted much attention in recent years. In cancer research, nanotechnology holds great promise for the development of targeted, localized delivery of anticancer drugs, in which only cancer cells are affected.

Such targeted-therapy methods would represent a major advance over current chemotherapy, in which anticancer drugs are distributed throughout the body, attacking healthy cells along with cancer cells and causing a number of adverse side effects.

By carrying out comprehensive studies on mice with human tumors, UCLA scientists have obtained results that move the research one step closer to this goal. In a paper published July 8 in the journal Small, researchers at UCLA's California NanoSystems Institute and Jonsson Comprehensive Cancer Center demonstrate that mesoporous silica nanoparticles (MSNs), tiny particles with thousands of pores, can store and deliver chemotherapeutic drugs in vivo and effectively suppress tumors in mice.

The researchers also showed that MSNs accumulate almost exclusively in tumors after administration and that the nanoparticles are excreted from the body after they have delivered their chemotherapeutic drugs.

The study was conducted jointly in the laboratories of Fuyu Tamanoi, a UCLA professor of microbiology, immunology and molecular genetics and director of the signal transduction and therapeutics program at UCLA's Jonsson Comprehensive Cancer Center, and Jeffrey Zink, a UCLA professor of chemistry and biochemistry. Tamanoi and Zink are researchers at the California NanoSystems Institute (CNSI) and are two of the co-directors of the CNSI's Nano Machine Center for Targeted Delivery and On-Demand Release. The lead investigator on the research is Jie Lu, a postdoctoral fellow in Tamanoi's lab. Monty Liong and Zongxi Li, researchers from Zink's lab, also contributed to this work.

In the study, researchers found that MSNs circulate in the bloodstream for extended periods of time and accumulate predominantly in tumors. The tumor accumulation could be further improved by attaching a targeting moiety to MSNs, the researchers said.

The treatment of mice with camptothecin-loaded MSNs led to shrinkage and regression of xenograft tumors. By the end of the treatment, the mice were essentially tumor free, and acute and long-term toxicity of MSNs to the mice was negligible. Mice with breast cancer were used in this study, but the researchers have recently obtained similar results using mice with human pancreatic cancer.

"Our present study shows, for the first time, that MSNs are effective for anticancer drug delivery and that the capacity for tumor suppression is significant," Tamanoi said.

"Two properties of these nanoparticles are important," Lu said. "First, their ability to accumulate in tumors is excellent. They appear to evade the surveillance mechanism that normally removes materials foreign to the body. Second, most of the nanoparticles that were injected into the mice were excreted out through urine and feces within four days. The latter results are quite interesting and might explain the low toxicity observed in the biocompatabilty experiments we conducted."

Researchers at the Nano Machine Center for Targeted Delivery and On-Demand Release are modifying MSNs -- which are easily modifiable -- so that the nanoparticles can be equipped with nanomachines. For example, nanovalves are being attached at the opening of the pores to control the release of anticancer drugs. In addition, the interior of the pores is being modified so that the light-induced release of anticancer drugs can be achieved.

"We can modify both the particles themselves and also the attachments on the particles in a wide variety of ways, which makes this material particularly attractive for engineering drug-delivery vehicles," Zink said.

The team is now planning future research that involves testing MSNs in a variety of animal-model systems and carrying out extensive studies on the safety of MSNs.

"Comprehensive investigation with practical dosages which are adequate and suitable for in vivo delivery of anticancer drugs is needed before MSNs can reach clinics as a drug-delivery system," Tamanoi said.

The research received support from National Institutes of Health and the National Science Foundation. In addition, NanoPacific Holdings Inc. provided critical support for the animal experiments.


Story Source:

The above story is based on materials provided by University of California - Los Angeles. The original article was written by Jennifer Marcus. Note: Materials may be edited for content and length.


Journal Reference:

  1. Jie Lu, Monty Liong, Zongxi Li, Jeffrey I. Zink, Fuyuhiko Tamanoi. Biocompatibility, Biodistribution, and Drug-Delivery Efficiency of Mesoporous Silica Nanoparticles for Cancer Therapy in Animals. Small, 2010; DOI: 10.1002/smll.201000538

Cite This Page:

University of California - Los Angeles. "Nanoparticles shrink tumors in mice." ScienceDaily. ScienceDaily, 11 July 2010. <www.sciencedaily.com/releases/2010/07/100709102723.htm>.
University of California - Los Angeles. (2010, July 11). Nanoparticles shrink tumors in mice. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2010/07/100709102723.htm
University of California - Los Angeles. "Nanoparticles shrink tumors in mice." ScienceDaily. www.sciencedaily.com/releases/2010/07/100709102723.htm (accessed April 24, 2014).

Share This



More Health & Medicine News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Fungus Killing Bats, Spreading in US

Deadly Fungus Killing Bats, Spreading in US

AP (Apr. 24, 2014) A disease that has killed more than six million cave-dwelling bats in the United States is on the move and wildlife biologists are worried. White Nose Syndrome, discovered in New York in 2006, has now spread to 25 states. (April 24) Video provided by AP
Powered by NewsLook.com
Companies Ramp Up Wellness to Lower Health Costs

Companies Ramp Up Wellness to Lower Health Costs

AP (Apr. 24, 2014) That little voice telling you to exercise, get in shape and get healthy is probably coming from your boss. More companies are beefing up wellness programs to try and cut down their health care costs. (April 24) Video provided by AP
Powered by NewsLook.com
Blood From World's Oldest Woman Suggests Life Limit

Blood From World's Oldest Woman Suggests Life Limit

Newsy (Apr. 24, 2014) Scientists say for the extremely elderly, their stem cells might reach a state of exhaustion. This could limit one's life span. Video provided by Newsy
Powered by NewsLook.com
FDA Wants To Ban Sales Of E-Cigarettes To Minors

FDA Wants To Ban Sales Of E-Cigarettes To Minors

Newsy (Apr. 24, 2014) The Food and Drug Administration wants to crack down on the use of e-cigarettes, banning the sale of the product to minors. 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