Navigation Links
Tumor wizardry wards off attacks from the immune system

Like the fictional wizard Harry Potter, some cancerous tumors seem capable of wrapping themselves in an invisibility cloak. Researchers at Washington University School of Medicine in St. Louis have found that pancreatic tumors hide from the body's immune surveillance by surrounding themselves with cells that make it hard for the immune system to detect them.

The tumor-protecting cells are white blood cells called regulatory T cells, or T-reg for short. Under ordinary circumstances, T-reg cells inhibit immune components responsible for killing unwanted cells -- this allows T-reg cells to help prevent autoimmune reactions.

The scientists discovered that cancerous cells take advantage of T-reg cells' suppressor ability, enlisting them to keep the immune system at bay. Their report appears in the July/August issue of the Journal of Immunotherapy.

"Earlier, we found that T-reg cells are much more prevalent in patients with breast cancer and pancreatic cancer than in healthy patients," says David C. Linehan, M.D., associate professor of surgery and a researcher with the Siteman Cancer Center. "The new findings show that tumors are directly responsible for the increase of T-reg cells and can attract T-reg cells to their vicinity. This could be one way for tumors to evade immune surveillance."

Linehan believes this could explain the failure of many experimental anti-cancer vaccines. Such vaccines are designed to rev up the immune response to cancer cells so that the immune system can attack tumors. But a tumor shielded with T-reg cells could potentially circumvent the immune system's attack and remain safe.

In mice implanted with pancreatic cancer, the researchers demonstrated that tumor growth caused an increase in T-reg cells in both the blood stream and in lymph nodes leading from the tumors.

When the research team blocked a signaling molecule that pancreatic tumors secrete in abundance, T-reg cells were no longer present in the tumor-draining lymph nodes, suggesting that this signaling molecule, referred to as TGF-beta, has an important role in weaving a tumor's cloak of invisibility. Such information could lead to a method for blocking tumors from using T-reg cells for protection. Other research by Linehan and colleagues showed that in mice with pancreatic cancer, simply depleting T-reg cells slowed tumor growth and increased survival time.

"We're looking at several potential ways to interfere with tumor recruitment of T-reg cells," Linehan says. "We'd like to see these findings advance cancer immunotherapy. We want to find a way to actively suppress T-reg cells and at the same time actively evoke an immune response to tumor-specific antigens."

In collaboration with other researchers at the School of Medicine, Linehan is planning to set up a clinical trial that pairs T-reg depletion with anti-cancer vaccine as a therapy for pancreatic cancer patients.

"We're attacking the problem from different angles hoping to translate these findings to our patients," Linehan says. "Right now, no effective treatment exists for pancreatic cancer."


'"/>

Source:Washington University School of Medicine


Related biology news :

1. Missing Receptor Molecule Causes Tumor Growth
2. Stem Cells Found In Cerebellum; Possible Cell of Origin for Childhood Brain Tumors
3. New Therapeutic Target Identified In Inherited Brain Tumor Disorder
4. Tumor cells that border normal tissue are told to leave
5. Tumor cells evade death through autophagy
6. Tumor-suppressor gene is critical for placenta development
7. Towards precise classification of cancers based on robust gene functional expression profiles
8. Virologists make major step towards understanding the process of HIV infection
9. Cats indifference towards sugar explained
10. Survey Uncovers Surprising Attitudes Towards HIV Vaccine Research
11. A new step towards an AIDS vaccine
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/19/2016)... , UAE, April 20, 2016 ... be implemented as a compact web-based "all-in-one" system solution ... the biometric fingerprint reader or the door interface with ... of modern access control systems. The minimal dimensions of ... ID readers into the building installations offer considerable freedom ...
(Date:4/15/2016)... 15, 2016 Research and ... Biometrics Market 2016-2020,"  report to their offering.  , ... , ,The global gait biometrics market is expected ... the period 2016-2020. Gait analysis generates ... be used to compute factors that are not ...
(Date:4/13/2016)... 2016  IMPOWER physicians supporting Medicaid patients in ... clinical standard in telehealth thanks to a new partnership ... platform, IMPOWER patients can routinely track key health measurements, ... index, and, when they opt in, share them with ... a local retail location at no cost. By leveraging ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... June 24, 2016  Regular discussions on a range of ... between the two entities said Poloz. Speaking at ... Ottawa , he pointed to the country,s inflation target, ... government. "In certain ... institutions have common economic goals, why not sit down and ...
(Date:6/23/2016)... , ... June 23, 2016 , ... ... pleased to announce the launch of their brand, UP4™ Probiotics, into Target stores ... 35 years, is proud to add Target to its list of well-respected retailers. ...
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... ... Plate® YM (Yeast and Mold) microbial test has received AOAC Research Institute approval ... of microbial tests introduced last year,” stated Bob Salter, Vice President of Regulatory ...
(Date:6/23/2016)... ... June 23, 2016 , ... STACS DNA Inc., the ... at the Arkansas State Crime Laboratory, has joined STACS DNA as a Field Application ... team,” said Jocelyn Tremblay, President and COO of STACS DNA. “In further expanding our ...
Breaking Biology Technology: