Navigation Links
Escape cancer, but age sooner? The dark side of the tumor suppressing process
Date:12/1/2008

Cells shut down and stop dividing when their DNA is damaged, in a process known as cellular senescence, so as to prevent damaged DNA from leading to unregulated cell division and therefore cancer. However, a new study, published in this week's issue of PLoS Biology, has found that when these cells shut down they also spew proteins into their surrounding environment. This causes inflammation and sets up conditions that support the development of age-related diseases including, ironically, cancer. The new research includes the first comprehensive molecular description of a paradoxical process that prevents cancer in younger people, but promotes age-related cancers and other maladies later in life.

"We provide for the first time a broad molecular description of how this well known mechanism for cancer prevention drives aging and age-related disease by changing the local tissue environment," said Judith Campisi, PhD, lead author of the study, who is a Faculty Member of the Buck Institute for Age Research and also Senior Scientist at Lawrence Berkeley National Laboratory.

The study shows that the senescent cells secrete inflammatory, growth-stimulating, immunomodulatory, and other proteins that dramatically change the tissue microenvironment, both in cells grown in the lab and in people undergoing chemotherapy, which can cause DNA damage.

The study also showed that normal cells that acquire a highly active, mutant version of a cancer-promoting protein known as Ras secrete higher levels of the tissue-altering molecules, as do cells that lose functions of the tumor suppressor protein p53. The study therefore explains why the presence of senescent cells can promote the growth and aggressiveness of nearby precancerous or cancer cells, and further defines a new mechanism by which precancerous or cancer cells that have lost the p53 tumor suppressor, or gained an oncogene such as Ras, promote cancer so efficiently.

"This study defines a new paradigm for how oncogenes promote, and how tumor suppressor genes suppress the development of cancer," said Campisi. "The established role for these genes is to control the cell itself. Our findings show that both types of genes also strongly change the tissue microenvironment, and therefore control cancer by mechanisms that depend not only on the response of the affected cells themselves, but also on the response of neighboring cells, or the local tissue environment." Campisi said the findings also help explain why cancer patients feel so sick when they get chemotherapy. "Chemotherapy is brutal -- both normal and cancerous cells are forced into senescence, with resulting secretion of inflammatory factors that can produce flu-like symptoms during treatment," Campisi said.

While Campisi emphasizes that chemotherapy can cure cancer, she says the study provides a cautionary note for younger patients who receive treatments that could promote the development of further cancers later in life. Campisi said the study points out the need for new biologically targeted therapies for cancer that exploit more specific differences between normal and cancer cells. Current DNA damaging chemotherapy focuses on cells that divide rapidly - impacting cancer cells, as well as all dividing cells including cells in the alimentary canal and hair follicles.

The next phase of the ongoing research involves efforts to encourage the body to eliminate senescent cells more rapidly than it normally does. "That's got to be the goal," said Campisi. "Although senescent cells exist for the good purpose of preventing cancer, we don't want them to hang around we want the body to be able to get rid of them."


'/>"/>

Contact: Sally Hubbard
press@plos.org
Public Library of Science
Source:Eurekalert

Related medicine news :

1. Yo Mujer: Woman Escapes from Abusive Marriage in New Spanish-Language Novel
2. Defending Champions Andy Potts and Leanda Cave Win 28th Annual Accenture Escape From Alcatraz(TM) Triathlon Sunday, June 8
3. Escape the Cold and Flu Season With a Free Vacation to the Sunshine State
4. Virtual game helps children escape realities of burn unit
5. Report Shows Progress in Fight Against Cancer, but Congress, States Must Step Up Efforts to Reduce Smoking, Lung Cancer
6. AMA Immediate Past President Ron Davis Loses Battle With Cancer, Leaves Enduring AMA and Public Health Legacy
7. First Major Medical Meeting Convening for MRI-guided Focused Ultrasound to Treat Cancer, Stroke, Fibroids, Other Conditions
8. Surgery Helps With Prostate Cancer, Sometimes
9. Dogster.com Teams With Morris Animal Foundation to Cure Canine Cancer, While Helping Dogs Suffering From Cancer Today - Makes $2 Donation for Each Subscription
10. American Lung Association Report Finds Lung Disease Death Rates Increasing While Cancer, Heart Disease and Stroke Death Rates Are Decreasing
11. June 2008 Mayo Clinic Health Letter Highlights New MRI Scanning Technology, Obesity-Related Cancer, and Do-It-Yourself Massage
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:10/13/2017)... ... ... Ellevate Network, the leading network for professional women, brought together some of ... their inaugural Summit in New York City in June. The event was livestreamed with ... 3 million. To watch the Mobilize Women video, click here . , ...
(Date:10/13/2017)... ... October 13, 2017 , ... Talented host, actor Rob Lowe, ... in a new episode of "Success Files," which is an award-winning educational program ... investigates each subject in-depth with passion and integrity. , Sciatica occurs when the ...
(Date:10/13/2017)... (PRWEB) , ... October 13, 2017 , ... “America On ... Christian identity. “America On The Brink” is the creation of published author, William ... several great-grandchildren. As a WWII veteran, he spent thirty years in the Navy. ...
(Date:10/12/2017)... ... , ... Planet Fitness, one of the largest and fastest growing franchisors and ... flagship location in Covington, LA at 401 N. U.S. Highway 190, in January of ... Depot in the Holiday Square shopping center. Its location allows it to serve both ...
(Date:10/12/2017)... ... October 12, 2017 , ... The American College of ... Carol Friedman, PhD, FACMI, during the Opening Session of AMIA’s Annual Symposium in Washington, ... In honor of Morris F. Collen, a pioneer in the field of medical informatics, ...
Breaking Medicine News(10 mins):
(Date:9/28/2017)... Sept. 28, 2017 Cohen Veterans Bioscience and ... use of wearable and home sensors for real-time monitoring ... Signal Foundation, a nonprofit organization focused on disruptive health ... an affordable analytical system to record and integrate behavioral, ... ...
(Date:9/25/2017)... 2017  EpiVax, Inc., a leader in the ... today announced the launch of EpiVax Oncology Inc., ... therapeutic cancer vaccines. EpiVax has provided $500,000 in ... enabling technologies to the new precision immunotherapy venture. ... Oncology as Chief Executive Officer. Gad brings over ...
(Date:9/19/2017)... ANN ARBOR, Mich. , Sept. 19, 2017 HistoSonics, Inc., a venture-backed medical ... the precise destruction of targeted tissues, announced three leadership team developments today:   ... Josh Stopek, PhD ... ... Veteran medical device executive ...
Breaking Medicine Technology: