Navigation Links
Protein found to control tumor growth in certain breast cancers

This protein was previously thought to play a role solely in the innate immune system's response to bacterial infection. In the new study, which will be published on-line by the Proceedings of the National Academy of Sciences of the United States of America on January 23, researchers showed for the first time that the protein, which is present in epithelial cells of the intestinal tract and lungs, is linked to the control of malignant cell growth.

The study found that over-expression of the protein resulted in the nearly total inhibition of estrogen-dependent tumor growth in mice, and the reduction of estrogen-induced proliferative responses in vitro. In stark contrast, significant tumor growth occurred when Nod1 was absent.

"We have greatly expanded our knowledge of the Nod1 pathway beyond its known role in response to infection," said Richard J. Ulevitch, Ph.D. Ulevitch, who led the study, is a professor and chairman of the Scripps Research Department of Immunology. "These unexpected findings offer the first real evidence that this pathway may regulate tumor growth and suggest a potentially new mechanism for controlling this type of breast cancer. Unraveling the intricate mechanisms of this previously unknown pathway opens up the potential for future development of novel therapeutics, and will hopefully stimulate researchers to take a fresh look at the Nod1 protein."

In the study, researchers looked at a number of biological processes where Nod1-dependent apoptotic (programmed cell death) pathways were a critical component, including the regulation of tumor cell growth where the failure of malignant cells to undergo cell death led to tumorigenesis. Cells derived from the human breast cancer epithelial cell line MCF-7 ?the cellular model for estrogen sensitive breast cancer tumors ?were used to induce tumor growth in severe combined immunodeficiency (SCID) mice. An over-expression of Nod1 in MCF-7 cells resulted in the inhibition of estrogen-dependent tumor growth in the SCID mice and a reduction of estrogen-induced proliferative responses in vitro. Moreover, scientists found that the tumors diminished rapidly in these mice, becoming virtually undetectable by the end of the experiment.

In MCF-7 cells where Nod1 was absent, the tumors flourished. In addition, there was an increased sensitivity to estrogen-induced cell proliferation and a failure to undergo Nod1-dependent apoptosis in vitro.

Taking these initial findings one step further, researchers implanted estrogen pellets in the SCID mice to accelerate tumorigenesis. In those mice receiving Nod1 cell lines tumor growth did not occur even in the presence of estrogen pellets, indicating that Nod1 acts as an effective cellular brake on estrogen-dependent tumor growth. In addition, the presence of Nod1 reduced the expression of the naturally occurring estrogen receptor in vitro, further indication that the protein mediates the sensitivity of hormone-dependent breast cancer cells to tumorigenesis.

"While still preliminary, our data adds another critical function to Nod1," Ulevitch said, "namely its ability to regulate the growth of estrogen-sensitive tumors formed by specific cell lines in immune deficient mice. The evidence uncovered in this study provides new insights into the physiological functions of Nod1 and supports our contention that there is a clear link between Nod1 and estrogen sensitivity in these cells. Our future studies will assess the relationship between the pathway uncovered in breast cancer and other hormone sensitive malignancies. Those studies may help in the development of new therapeutic approaches with the potential to stabilize or even eradicate hormone-sensitive tumors."


Source:Scripps Research Institute

Related biology news :

1. Quantum Dots Research Leads to New Knowledge about Protein Binding in Plants
2. Protein discovery could unlock the secret to better TB treatment
3. Researchers Uncover Key Step In Manufacture of Memory Protein
4. An HIV Protein Plays a Surprising Role in Gene Activation
5. Protein Packages Found To Activate Genes; May Be What Regulates Development And Disease
6. New SARS Protein Linked To Important Cell Doorway
7. The Shapes Of Life: NIGMS Project Yields More Than 1,000 Protein Structures
8. PANTHER Protein Classification System Database 5.0
9. Duke Chemists Isolating Individual Molecules Of Toxic Protein In Alzheimers, Parkinsons Disease
10. Newly Discovered Compound Blocks Known Cancer-Causing Protein
11. UF Researchers Map Bacterial Proteins That Cause Tooth Loss
Post Your Comments:

(Date:11/17/2015)... Nov. 17, 2015  Vigilant Solutions announces today that ... Board of Directors. --> ... retiring from the partnership at TPG Capital, one of ... over $140 Billion in revenue.  He founded and led ... the TPG companies, from 1997 to 2013.  In his ...
(Date:11/16/2015)... , Nov 16, 2015  Synaptics Inc. ... human interface solutions, today announced expansion of its ... ™ touch controller and display driver integration ... of smartphones. These new TDDI products add to ... (HD resolution), TD4302 (WQHD resolution), and TD4322 (FHD ...
(Date:11/12/2015)... 2015  Arxspan has entered into an agreement ... for use of its ArxLab cloud-based suite of ... partnership will support the institute,s efforts to electronically ... information internally and with external collaborators. The ArxLab ... the Institute,s electronic laboratory notebook, compound and assay ...
Breaking Biology News(10 mins):
(Date:12/1/2015)... Texas (PRWEB) , ... December ... ... , a leading relationship marketing company specializing in scientifically backed, age-defying products, ... January 2016 issue, which highlights the exponential success and unrivaled opportunities that ...
(Date:12/1/2015)... (PRWEB) , ... December 01, 2015 , ... ... global meeting this month and Dr. J. Kyle Mathews will join ... includes the new single site hysterectomy. , An experienced urogynecologist, founder of Plano ...
(Date:11/30/2015)... ... ... Global Stem Cells Group announced that its scientific team is in the ... cells. The announcement starts a new phase toward launching the simple, quick system for ... lipoaspirate obtained from liposuction of excess adipose tissue. , Lipoaspirate, contains a large ...
(Date:11/30/2015)... MONTREAL , Dec. 1, 2015 /PRNewswire/ - BioAmber Inc. (NYSE: ... that it has joined the American Business Act on Climate ... economy that are standing with the Obama Administration to demonstrate ... for a strong outcome to the COP21 Paris ... . --> Sarnia, Canada . ...
Breaking Biology Technology: