New revelations in epigenetic control shed light on breast cancer

March 5, 2008

Epigenetic regulation – modifications to the structure of chromatin that influence which genes are expressed in a cell – is a key player in embryonic development and cancer formation. Researchers at the European Molecular Biology Laboratory [EMBL] in Heidelberg now gained new insight into one crucial epigenetic mechanism and reveal that it acts much faster than assumed.

In this week's issue of Nature they report that estrogen causes rapid epigenetic changes in breast cancer cells. The new findings impact upon our understanding of how cells interpret their DNA and suggest that epigenetic regulation can affect gene expression immediately and long-term.

Epigenetic changes to the structure of chromatin – tightly packaged DNA - grant or deny access to the molecular machinery that transcribes DNA and thereby regulate gene expression. One of these mechanisms is DNA methylation, where a small chemical residue called a methyl group is added to strategic bases on the DNA. The methyl group prevents the transcription machinery from docking and thereby shuts down gene expression. For a long time scientists have considered methylation a mechanism of long-term regulation of a gene's activity, because the methylation marks are stable and maintained through cellular replication.

EMBL researchers of the group of Frank Gannon, current director of the Science Foundation Ireland, now found out that methylation marks occur rapidly in breast cancer cells in response to hormones such as estrogen or drug compounds. Estrogen withdrawal or treatment with the established anticancer drug doxorubicin cause the methyl groups to be removed from regulatory regions of specific genes within tens of minutes in human breast cancer cells. The treatment sets off a whole cycle of events: initial demethylation renders silent genes active and subsequent remethylation shuts them down again. This cycle repeats itself every 1.5 hours.

"We observed that unlike assumed for a long time methylation can act on a very short timescale. The results challenge our understanding of epigenetics as a means to regulate gene expression permanently," says Sara Kangaspeska, who carried out the research together with Brenda Stride.

The new insights into the cyclical nature of methylation might shed light on the molecular bases of cancer and development, both processes involving epigenetic mechanisms.

"In particular breast cancer is affected by estrogen signalling and changes in epigenetic control," says George Reid, co-senior author of the study. "Our next step will be to find small molecules that target the cyclical methylation processes to elucidate their precise role."

Source: European Molecular Biology Laboratory

4.4 /5 (5 votes)  

Rank 4.4 /5 (5 votes)
Tags

Relevant PhysicsForums posts
  • Is Everyday Technology Killing Us?
    createdFeb 08, 2012
  • Exercise and weight loss
    createdFeb 08, 2012
  • Why do we have head aches? Our brains can't feel anything.
    createdFeb 07, 2012
  • "The end of diseases" by David Agus, interview from Daily Show with Jon Stewart
    createdFeb 04, 2012
  • Oncolytic adenovirus
    createdFeb 04, 2012
  • Nutrition label stuffs and diets
    createdFeb 02, 2012
  • More from Physics Forums - Medical Sciences

More news stories

Researchers make breakthrough in stem cell research

(Medical Xpress) -- University of Queensland scientists have developed a world-first method for producing adult stem cells that will substantially impact patients who have a range of serious diseases.

Medicine & Health / Research

created 50 minutes ago | popularity 5 / 5 (2) | comments 0 | with audio podcast

Georgia Tech develops software for the rapid analysis of foodborne pathogens

2011 brought two of the deadliest bacterial outbreaks the world has seen during the last 25 years. The two epidemics accounted for more than 4,200 cases of infectious disease and 80 deaths. Software developed at Georgia Tech ...

Medicine & Health / Diseases

created 42 minutes ago | popularity not rated yet | comments 0

Can Viagra treat childhood lymphatic disorder?

(Medical Xpress) -- A surprising potential therapy for severe, hard-to-treat malformations of the lymphatic system is now being studied at the Stanford School of Medicine and Lucile Packard Children’s Hospital: researchers ...

Medicine & Health / Diseases

created 17 minutes ago | popularity not rated yet | comments 0 | with audio podcast

Don't ignore kids' snores

(Medical Xpress) -- Your ears aren’t playing tricks on you – that is the sound of snoring you hear from the bedroom of your preschooler. Snoring is common in children, but in some cases it can be a symptom of a ...

Medicine & Health / Diseases

created 7 minutes ago | popularity not rated yet | comments 0

WHO calls for stepped-up fight against leprosy

The World Health Organization called Monday for greater efforts to fight leprosy, warning the disfiguring disease was defying efforts to wipe it out across many countries in the Asia-Pacific region.

Medicine & Health / Diseases

created 13 minutes ago | popularity not rated yet | comments 0


New molecule has potential to help treat genetic diseases and HIV

(PhysOrg.com) -- Chemists at The University of Texas at Austin have created a molecule that's so good at tangling itself inside the double helix of a DNA sequence that it can stay there for up to 16 days before ...

With climate change, today's '100-year floods' may happen every three to 20 years: research

Last August, Hurricane Irene spun through the Caribbean and parts of the eastern United States, leaving widespread wreckage in its wake. The Category 3 storm whipped up water levels, generating storm surges ...

Researchers make better heat sensor based on butterfly wings

(PhysOrg.com) -- Scientists have long known that butterfly wings produce their iridescent colors by bouncing light around and between tiny ridges in structures made of chitin. More recently they’ve discovered ...

Social psychologist: Lust makes you smarter and evidence that seven deadly sins are good for you

(Medical Xpress) -- Good news for lovers on Valentine’s Day - the seven deadly sins, including Lust, are good for you. University of Melbourne social psychologist Dr Simon Laham uses modern research to make a compelling ...

The joy of cheques

An electronic cheque which eliminates the need for costly processing by banks but preserves the simplicity and ease of a traditional cheque book has been designed by a team of academics in the UK.

Research shows promise in converting camelina oil into jet fuel

(PhysOrg.com) -- Researchers at Montana State University-Northern have developed a process to convert camelina oil to jet fuel and other high-value chemicals. MSU has applied for a U.S. patent and research is ongoing.