Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Breast cancer tumor-initiating cells use mTOR signaling to recruit suppressor cells to promote tumor

17.05.2016

Not every breast cancer tumor follows the same path to grow. Some tumors have the assistance of myeloid-derived suppressor cells (MDSCs), a diverse type of immune cell involved in the suppression of the body's response against tumors. How breast cancer cells recruit MDSCs is not completely understood, but in a paper released today in Nature Cell Biology, Baylor College of Medicine researchers report a new mechanism that helps cancer cells engage MDSCs.

"There are alternative paths a tumor may take without the MDSCs, but those cancer cells that take the mTOR path of activity tend to have more MDSCs through the production of granulocyte-colony stimulating factor (G-CSF), which drives the accumulation of MDSCs," said corresponding author Dr. Xiang Zhang, a McNair Scholar and assistant professor of molecular and cellular biology at Baylor College of Medicine.


The mTOR pathway, an important pathway controlling cell growth and metabolism, is aberrantly activated in some breast tumors. This activation leads to increased expression of granulocytic colony formation factor (G-CSF, blue triangleEnglish ), which is then released into the circulation and stimulates the accumulation of myeloid-derived suppressor cells (MDSCs). MDSCs recruited to tumors directly enhance tumor initiation capacity. They also modulate the functions of other immune cells to dampen the anti-tumor immunity. RTK, receptor tyrosine kinase.

Credit: X.Zhang

Knowing how cancer cells and MDSCs interact with each other helps researchers understand the events that may lead to tumor growth and metastasis and identify potential therapeutic targets. For instance, "determining that a patient's tumor is using the mTOR pathway would indicate that the cancer cells are more likely to depend on MDSCs for progression," said Zhang, who also is with the Lester and Sue Smith Breast Center at Baylor.

"This information suggests that, in this case, available therapies for mTOR combined with therapies for MDSCs represent potential therapeutic strategies." Tumors that do not use the mTOR signaling pathway would not be expected to respond as well to the same therapies.

... more about:
»cancer cells »mTOR »mTOR signaling »suppressor

The discovery of Zhang and colleagues is much in line with the concept of personalized medicine. "People talk about the specific mutations one patient's tumor has that are not in another patient's tumor. The same type of tumors having different mutations may warrant different treatments; that is personalized medicine," explained Zhang.

"We are trying to come from a different angle. We are trying to enrich this concept by saying that not only tumor-intrinsic characteristics are different from patient to patient, but, related to that, there is also diversity in terms of the immune components. Different tumors may evolve via different characteristics of the tumor and the immune response."

MDCSs are just one type of aberrant immune cell associated with the tumor. "In addition, there are other immune cells associated with the tumor - monocytes, macrophages, different subsets of T cells - that can either attack or help the tumor. All those cells may vary from patient to patient, and we don't really understand that yet," said Zhang.

In addition, MDSCs also play a role in non-cancer situations. For instance, in chronic inflammation, these cells try to suppress the inflammation; in this case, they play a pro-health role. So, "simply eliminating all MDSCs to treat cancer may likely result in negative side effects, such as autoimmune disease. That's why it's necessary to further characterize the diversity, to find the specific subsets of MDSCs that are tumor specific," said Zhang.

###

Other contributors to this work include Thomas Welte from Baylor and the Diana Helis Henry Medical Research Foundation, New Orleans; Ik Sun Kim, Lin Tian, Xia Gao, Hai Wang, June Li, Xue B. Holdman, Jason I. Herschkowitz, Adam Pond, Sarah Kurley, Tuan Nguyen, Lan Liao, Lacey E. Dobrolecki, Qianxing Mo, Dean P. Edwards, Shixia Huang, Li Xin, Jianming Xu, Yi Li, Michael T. Lewis, Thomas F. Westbrook, and Jeffrey M. Rosen (co-corresponding author), all from Baylor; and Guorui Xie, Lan Pang and Tian Wang from the department of microbiology and immunology at The University of Texas Medical Branch, Galveston.

This work is supported by National Cancer Institute (CA151293, CA16303), Breast Cancer Research Foundation, US Department of Defense (DAMD W81XWH-13-1-0195), Susan G. Komen (CCR14298445), McNair Medical Institute, and Diana Helis Henry Medical Research Foundation.

Media Contact

Dana Benson
benson@bcm.edu
713-798-4710

 @bcmhouston

https://www.bcm.edu/news 

Dana Benson | EurekAlert!

Further reports about: cancer cells mTOR mTOR signaling suppressor

More articles from Life Sciences:

nachricht Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

nachricht How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>