Discoveries in mitochondria open new field of cancer research
(Medical Xpress) -- Researchers at Virginia Commonwealth University Massey Cancer Center have revealed novel mechanisms in mitochondria that have implications for cancer as well as many other age-related diseases such as Parkinsons disease, heart disease and hypertension. This discovery has pioneered the formation of a whole new field within epigenetics research ripe with possibilities of developing future gene therapies to treat cancer and age-associated diseases.
Shirley M. Taylor, Ph.D., researcher at VCU Massey Cancer Center and associate professor in the VCU Department of Microbiology and Immunology at VCU School of Medicine, was a graduate student when her research helped establish the field of epigenetics (epigenetics refers to the process that controls which genes get expressed in the nucleus of a cell, ultimately determining that cells biological characteristics). Now decades later, Taylor and her colleagues have further expanded the field of epigenetics into a new area of research they created by discovering enzymes in mitochondria that were previously known to exist only in nuclei.
In mammals, all cells have two distinct genomes, which include all of an organisms hereditary information. One set exists in the nucleus while the other exists in the mitochondrion, the energy generator of the cell.
Published in the journal Proceedings of the National Academy of Sciences (PNAS), Taylors study found two DNA modifications in the mitochondrial genome: methylated cytosine, known to function in the nucleus by silencing the expression of certain genes; and hydroxymethyl cytosine, which removes the silencing mark imposed by the cytosine methylation.
Together, these modifications act like a genetic on/off switch in a process known as DNA methylation. Taylors team also showed that the enzyme responsible for DNA methylation was present in mammalian mitochondria. The presence of these DNA modifications leads the researchers to believe that a system of gene control similar to what occurs in the nucleus is present in mitochondria, functioning to ensure the correct levels of proteins needed for proper energy generation.
In diseases such as cancer, epigenetic control is lost, says Taylor. Genes that should be switched on are switched off and vice versa, leading to uncontrolled growth. Our research indicates that errors in gene expression could be unfolding in mitochondria, possibly contributing to loss of mitochondrial function typical of cancer and a host of other age-related diseases.
Taylors team is currently working to force into mitochondria more of the enzyme responsible for forming the silencing mark, and to identify enzymes responsible for removing it. This should allow the researchers to observe whether these marks impact mitochondrial ability to generate energy. The researchers are also comparing the amount of DNA methylation in diseased cells versus healthy cells to determine whether mitochondrial gene expression plays a role in various diseases.
Many diseases that afflict the elderly seem to have defects in mitochondrial function, says Taylor. We are working to determine whether epigenetic control is a factor contributing to these defects. If so, drugs known to impact gene expression in the nucleus may be useful in reversing damage caused by improper gene expression in mitochondria.
Taylor collaborated on this study with Richard G. Moran, Ph.D., associate director for basic research at VCU Massey Cancer Center and professor in the Department of Pharmacology and Toxicology at VCU School of Medicine. Other collaborators include doctoral students Lisa S. Shock, Prashant V. Thakkar and Erica J. Peterson from the VCU Department of Microbiology and Immunology. The study was partially funded by the National Cancer Institute and by a pilot project award from Massey.
More information: The full manuscript is available online at www.pnas.org/conte… ull.pdf+html
Provided by Virginia Commonwealth University
- Researchers identify new function of protein in cellular respiration Jan 28, 2009 | not rated yet | 0
- Lipid involved with gene regulation uncovered Sep 04, 2009 | not rated yet | 0
- Lipid involved with gene regulation uncovered Sep 08, 2009 | not rated yet | 0
- Mitochondrial DNA mutations can cause degenerative heart and muscle disease Feb 14, 2008 | not rated yet | 0
- Newly found enzymes may play early role in cancer Dec 24, 2008 | not rated yet | 0
- Motion perception revisited: High Phi effect challenges established motion perception assumptions Apr 23, 2013 | 3 / 5 (2) | 2
- Anything you can do I can do better: Neuromolecular foundations of the superiority illusion (Update) Apr 02, 2013 | 4.5 / 5 (11) | 5
- The visual system as economist: Neural resource allocation in visual adaptation Mar 30, 2013 | 5 / 5 (2) | 9
- Separate lives: Neuronal and organismal lifespans decoupled Mar 27, 2013 | 4.9 / 5 (8) | 0
- Sizing things up: The evolutionary neurobiology of scale invariance Feb 28, 2013 | 4.8 / 5 (10) | 14
Pressure-volume curve: Elastic Recoil Pressure don't make sense
May 18, 2013 From pressure-volume curve of the lung and chest wall (attached photo), I don't understand why would the elastic recoil pressure of the lung is...
If you became brain-dead, would you want them to pull the plug?
May 17, 2013 I'd want the rest of me to stay alive. Sure it's a lousy way to live but it beats being all-the-way dead. Maybe if I make it 20 years they'll...
MRI bill question
May 15, 2013 Dear PFers, The hospital gave us a $12k bill for one MRI (head with contrast). The people I talked to at the hospital tell me that they do not...
Ratio of Hydrogen of Oxygen in Dessicated Animal Protein
May 13, 2013 As an experiment, for the past few months I've been consuming at least one portion of Jell-O or unflavored Knox gelatin per day. I'm 64, in very...
Alcohol and acetaminophen
May 13, 2013 Edit: sorry for the typo in the title , can't edit I looked around on google quite a bit and it's very hard to find precise information on the...
Marie Curie's leukemia
May 13, 2013 Does anyone know what might be the cause of Marie Curie's cancer
- More from Physics Forums - Medical Sciences
More news stories
The use of a smartphone application significantly improves patients' preparation for a colonoscopy, according to new research presented today at Digestive Disease Week (DDW). The preparation process, which begins days in ...
Cancer 10 hours ago | not rated yet | 0
Research presented at Digestive Disease Week (DDW) explores new methods for managing digestive health through diet and lifestyle.
Cancer 10 hours ago | not rated yet | 1
A ground-breaking advance in colonoscopy technology signals the future of colorectal care, according to research presented today at Digestive Disease Week(DDW). Additional research focuses on optimizing the minimal withdrawal ...
Cancer May 18, 2013 | 5 / 5 (2) | 0
(HealthDay)—Concurrent use of two immune checkpoint antibodies—ipilimumab and nivolumab—may be effective for the treatment of advanced melanoma, according to a proof-of-principal study presented in ...
Cancer May 17, 2013 | not rated yet | 0
(HealthDay)—The risks of metastasis and death associated with cutaneous squamous cell carcinoma (CSCC) are low, but significant, and risk factors for poor outcome include tumor diameter, invasion beyond ...
Cancer May 17, 2013 | not rated yet | 0 |
The devastating effect of Alzheimer's disease on bilingual people has been thrown into focus in Canada, where the sudden loss of a second language can leave sufferers feeling like strangers in their own country.
1 hour ago | not rated yet | 0
The hunt for an HIV vaccine has gobbled up $8 billion in the past decade, and the failure of the most recent efficacy trial has delivered yet another setback to 26 years of efforts.
2 hours ago | not rated yet | 0
Regular consumption of coffee is associated with a reduced risk of primary sclerosing cholangitis (PSC), an autoimmune liver disease, Mayo Clinic research shows. The findings were being presented at the Digestive Disease ...
10 hours ago | not rated yet | 0 |
Patients with treatment-resistant major depression saw dramatic improvement in their illness after treatment with ketamine, an anesthetic, according to the largest ketamine clinical trial to-date led by researchers from the ...
10 hours ago | 4.7 / 5 (3) | 0 |
There are significant cost and risk factors associated with two procedures commonly used to diagnose or treat gastrointestinal problems, according to research presented at Digestive Disease Week (DDW).
10 hours ago | not rated yet | 0