Navigation Links
CSHL scientists identify and repress breast cancer stem cells in mouse tissue
Date:12/17/2007

Cold Spring Harbor, NY By manipulating highly specific gene-regulating molecules called microRNAs, scientists at Cold Spring Harbor Laboratory (CSHL) report that they have succeeded in singling out and repressing stem-like cells in mouse breast tissue cells that are widely thought to give rise to cancer.

If certain forms of breast cancer do indeed have their origin in wayward stem cells, as we believe to be the case, then it is critical to find ways to selectively attack that tumor-initiating population, said Gregory Hannon, Ph.D., CSHL professor and Howard Hughes Medical Institute Investigator. Hannon also is head of a lab focusing on small-RNA research at CSHL and corresponding author of a paper reporting the new research, published in the latest issue of Genes and Development.

We have shown that a microRNA called let-7, whose expression has previously been associated with tumor suppression, can be delivered to a sample of breast-tissue cells, where it can help us to distinguish stem-like tumor-initiating cells from other, more fully developed cells in the sample. Even more exciting, we found that by expressing let-7 in the sample, we were able to attack and essentially eliminate, very specifically, just that subpopulation of potentially dangerous progenitor cells.

The study was done in collaboration with Senthil Muthuswamy Ph.D., an expert in breast cancer research who heads a CSHL lab focusing on understanding the changes in the biology of breast epithelial cells during the initiation and progression of cancer. Dr. Muthuswamy emphasized that a key ingredient that made this study successful is the use of a mouse breast-derived model cell system called COMMA-1D that not only includes differentiated cells but also stem-like progenitors, in varying stages of maturity, or differentiation.

Unexpected Impact of Conventional Chemotherapy

No therapies currently exist that target stem-like tumor-initiating cells, whose existence in diverse tissues including breast, lung, brain and colon, as well as in the blood, has been demonstrated in a line of research stretching back to 2001. In that year, John E. Dick of the University of Toronto identified cancer stem cells in the blood of leukemia patients.

The cancer stem cell hypothesis is controversial, in part, because of the challenge it represents for current cancer therapy, which regards all tumor cells as potentially capable of spreading the disease, and which seeks to reduce tumor mass and destroy the maximum possible number of tumor cells. In the cancer stem cell hypothesis, reduction of tumor volume alone will not suffice if the stem cells which originally gave rise to the cancer are not specifically targeted and destroyed.

The new Cold Spring Harbor Laboratory research not only suggests one possible way of accomplishing this therapeutic goal the Hannon lab is initiating a demonstration study in mice but it also demonstrated that one component of a chemotherapy cocktail currently used as first-line therapy against certain kinds of breast cancer has the potential to actually enrich the subpopulation of stem-like cells that serve as cancer progenitors.

We found that administration of cyclophosphamide in our mouse cell sample had the effect of enriching for these cells, Hannon said, which suggests that we need to look carefully at these therapies in model systems to see if the effects we see in cell culture are mirrored in real tumors and then, to gauge what effect that has on metastasis and relapse following therapy.

It has been known for some time that stem and progenitor cells possess unique defenses, as compared with mature, or differentiated cells, which, unlike their stem-like mothers do not have the capacity to renew themselves or to generate multiple cell-types. Stem cells, for instance, are thought to be able to pump toxins out of their cellular domain, much as do fully differentiated tumor cells that have developed resistance to chemotherapy.


'/>"/>

Contact: Jim Bono
bono@cshl.edu
516-367-8455
Cold Spring Harbor Laboratory
Source:Eurekalert

Related biology news :

1. UK scientists working to help cut ID theft
2. Scientists show that mitochondrial DNA variants are linked to risk factors for type 2 diabetes
3. Comet probes reveal evidence of origin of life, scientists claim
4. Scientists link fragile X tremor/ataxia syndrome to binding protein in RNA
5. Male elephants get photo IDs from scientists
6. Scientists retrace evolution with first atomic structure of an ancient protein
7. Muscle mass: Scientists identify novel mode of transcriptional regulation during myogenesis
8. Carnegie Mellon scientists develop nanogels that enable controlled delivery of carbohydrate drugs
9. Clemson scientists shed light on molecules in living cells
10. Scientists tackle mystery mountain illness
11. T. rex quicker than Becks, say scientists
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/21/2016)... VANCOUVER, British Columbia , June 21, 2016 ... been appointed to the new role of principal ... has been named the director of customer development. ... , NuData,s chief technical officer. The moves reflect ... development teams in response to high customer demand ...
(Date:6/9/2016)... -- Perkotek an innovation leader in attendance control systems is proud to announce the introduction ... to make sure the right employees are actually signing in, and to even control ... ... ... ...
(Date:6/2/2016)... June 2, 2016 The Department of ... awarded the 44 million US Dollar project, for the ... Plates including Personalization, Enrolment, and IT Infrastructure , ... the production and implementation of Identity Management Solutions. Numerous renowned ... Decatur was selected for the most ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... -- Houston Methodist Willowbrook Hospital has signed a ... serve as their official health care provider. As ... provide sponsorship support, athletic training services, and most ... athletes and families. "We are excited ... to bring Houston Methodist quality services and programs ...
(Date:6/23/2016)... ... 2016 , ... Supplyframe, the Industry Network for electronics hardware ... . Located in Pasadena, Calif., the Design Lab’s mission is to bring together ... built and brought to market. , The Design Lab is Supplyframe’s physical representation ...
(Date:6/23/2016)... June 23, 2016 ... 2016;12(1):22-8 http://doi.org/10.17925/OHR.2016.12.01.22 Published recently ... peer-reviewed journal from touchONCOLOGY, Andrew D Zelenetz ... of cancer care is placing an increasing burden ... expensive biologic therapies. With the patents on many ...
(Date:6/23/2016)... 22, 2016  Amgen (NASDAQ: AMGN ) ... QB3@953 life sciences incubator to accelerate the development ... laboratory space at QB3@953 was created to help high-potential ... for many early stage organizations - access to laboratory ... Amgen launched two "Amgen Golden Ticket" awards, providing each ...
Breaking Biology Technology: