Featured Research

from universities, journals, and other organizations

Immune System Can Hurt As Well As Help Fight Cancer, Study Shows

Date:
October 1, 2008
Source:
University of Pennsylvania School of Medicine
Summary:
Researchers at the University of Pennsylvania School of Medicine have found that some proteins of the immune system can promote tumor growth. Investigators found that instead of fighting tumors, the protein C5a, which is produced during an immune response to a developing tumor, helps tumors build molecular shields against T-cell attack.

Model of the C5a molecule, part of the immune complement system.
Credit: John D. Lambris, PhD, University of Pennsylvania School of Medicine

Researchers at the University of Pennsylvania School of Medicine have found that some proteins of the immune system can promote tumor growth. Investigators found that instead of fighting tumors, the protein C5a, which is produced during an immune response to a developing tumor, helps tumors build molecular shields against T-cell attack. These findings appeared online this week in Nature Immunology.

C5a is part of the complement system, one of the body’s immune defenses against pathogens. When activated, the system’s proteins rid the body of microbes and foreign cells. Many cancer treatments are aimed at boosting the immune system to kill tumors.

“Until now, everyone thought that the complement system was there to eliminate tumor cells. We found that in some conditions, the complement system can promote tumor growth, depending on the specific tumor and the specific environment in which the tumors are developing,” says John Lambris, PhD, the Dr. Ralph and Sallie Weaver Professor of Research Medicine.

However, Penn researchers found that in a mouse model, activation of the complement system in tumor tissue leads to the generation of C5a, which recruits myeloid-derived suppressor cells (MDSC) to tumors. These MDSCs block the function of CD8+ T cells, which would normally dismantle a tumor.

Researchers also found that blocking the C5a receptor on cell surfaces impairs tumor growth at the same rate of Paclitaxel, a chemotherapy drug. This discovery could lead to new cancer treatments with far fewer side effects than chemotherapy, surmise the investigators.

“Researchers are trying to introduce immune therapies and anti-tumor vaccines, but most of these vaccines fail,” says Lambris. “We show in this study a possible mechanism how to overcome this problem.” Lambris and his team are conducting studies that apply the approaches outlined in this paper to five models of cancer.

In addition to Lambris, Penn co-authors are Maciej M. Markiewski, Robert A. DeAngelis, Salome K Ricklin-Lichtsteiner, Anna Koutoulaki, Fabian Benencia (now at the University of Ohio), and George Coukos, as well as Craig Gerard, Children’s Hospital, Boston. The National Institutes of Health provided funding for this research.


Story Source:

The above story is based on materials provided by University of Pennsylvania School of Medicine. Note: Materials may be edited for content and length.


Cite This Page:

University of Pennsylvania School of Medicine. "Immune System Can Hurt As Well As Help Fight Cancer, Study Shows." ScienceDaily. ScienceDaily, 1 October 2008. <www.sciencedaily.com/releases/2008/09/080929153458.htm>.
University of Pennsylvania School of Medicine. (2008, October 1). Immune System Can Hurt As Well As Help Fight Cancer, Study Shows. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2008/09/080929153458.htm
University of Pennsylvania School of Medicine. "Immune System Can Hurt As Well As Help Fight Cancer, Study Shows." ScienceDaily. www.sciencedaily.com/releases/2008/09/080929153458.htm (accessed October 21, 2014).

Share This



More Health & Medicine News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How Nigeria Beat Its Ebola Outbreak

How Nigeria Beat Its Ebola Outbreak

Newsy (Oct. 20, 2014) The World Health Organization has declared Nigeria free of Ebola. Health experts credit a bit of luck and the government's initial response. Video provided by Newsy
Powered by NewsLook.com
Another Study Suggests Viagra Is Good For The Heart

Another Study Suggests Viagra Is Good For The Heart

Newsy (Oct. 20, 2014) An ingredient in erectile-dysfunction medications such as Viagra could improve heart function. Perhaps not surprising, given Viagra's history. Video provided by Newsy
Powered by NewsLook.com
Ebola Worries End for Dozens on U.S. Watch Lists

Ebola Worries End for Dozens on U.S. Watch Lists

Reuters - US Online Video (Oct. 20, 2014) Forty-three people who had contact with Thomas Eric Duncan, the first person diagnosed with Ebola in the U.S., were cleared overnight of twice-daily monitoring after 21 days of showing no symptoms. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
CDC Calls for New Ebola Safety Guidelines

CDC Calls for New Ebola Safety Guidelines

AP (Oct. 20, 2014) Centers for Disease Control and Prevention Director Dr. Tom Frieden laid out new guidelines for health care workers when dealing with the deadly Ebola virus including new precautions when taking off personal protective equipment. (Oct. 20) Video provided by AP
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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