Navigation Links
Potential for added medical benefits uncovered for widely used breast cancer drug
Date:11/7/2013

Exemestane, a synthetic steroid drug widely prescribed to fight breast cancers that thrive on estrogens, not only inhibits the production of the hormone, but also appears to protect cells throughout the body against damage induced by UV radiation, inflammation and other assaults, according to results of research by Johns Hopkins scientists.

A summary of the research, performed on a variety of different animal and human cells, was published online in the Proceedings of the National Academy of Sciences on Nov. 4, and suggests that exemestane's effectiveness against breast cancer could be due to more than its ability to halt estrogen production, the scientists say. The study's results further imply that the drug, a so-called aromatase (estrogen synthesis) inhibitor, could potentially be prescribed more widely, including to men, as a way to counteract the wear and tear on cells that often leads to chronic diseases.

"Cells already have their own elaborate protective mechanisms, and in many cases they are 'idling.' The right drugs and foods can turn them on to full capacity," says Paul Talalay, M.D., the John Jacob Abel Distinguished Service Professor of Pharmacology and Molecular Sciences at the Johns Hopkins University School of Medicine. "In our cell studies, we found that exemestane does exactly that," he adds.

Talalay explains that cells are constantly under assault from a wide range of potentially lethal agents. UV radiation from the sun can cause errors in DNA sequences; reactive oxygen species a class of unstable, oxygen-containing chemicals that are a natural byproduct of cellular functioning can build up and cause damage to DNA and proteins; and ongoing inflammation can damage many essential cell functions.

To withstand the pressures against them, cells have evolved various mechanisms for protecting themselves. One involves turning on genes that produce a "SWAT team" of proteins, he notes, collectively called the phase 2 response. In normal cells, this response is not fully active. In previous work, the Talalay group found that sulforaphane, a chemical found in broccoli and other vegetables, can ramp up the phase 2 response and help protect cells from the constant wear and tear that they experience.

"Looking at the chemical structure of exemestane, I realized that it was similar to sulforaphane, and I wondered if it too could boost cells' phase 2 protective responses," says Talalay.

To demonstrate that exemestane revs up the phase 2 response, Hua Liu, a research associate in Talalay's laboratory, tested exemestane's effects on various types of cells, including liver tumor and skin cells from a mouse, human cells from the eye's retina, and rat heart cells. As expected, the addition of exemestane elevated the activity of typical protective phase 2 response enzymes in all of the cells tested, a result similar to the effects of adding sulforaphane.

Exemestane was also effective in reducing the amount of reactive oxygen species in human retinal cells, where they are thought to contribute to age-related macular degeneration. It was also able to protect rat heart cells from similar damage.

To test the drug's ability to protect skin cells from UV-induced damage, Liu treated mouse skin cells with exemestane a day before subjecting them to UV radiation and, again, exemestane was able to protect the cells significantly, Liu and Talalay say.

Assessing exemestane's ability to protect cells from inflammation produced a surprise, Talalay notes. In all the other tests, Liu and Talalay had tried not only exemestane but also a mixture of exemestane and sulforaphane. They generally found that the two had an additive effect, suggesting that they both worked in a similar way and were more or less interchangeable. However, when mouse immune cells were exposed to both exemestane and sulforaphane, the two together were much more potent and at lower doses than either chemical alone.

"Our research showed unexpectedly that exemestane has multiple actions, which suggests that a wider use of exemestane should be considered if clinical tests confirm our cellular studies," says Talalay. "Of course, even if clinical tests confirm what we saw in cells, exemestane may not be appropriate for everyone. It's already advocated as a preventive measure for high-risk breast cancer populations, but it may also be valuable in preventing other noncancerous chronic diseases."

Talalay notes that the drug is already approved by the U.S. Food and Drug Administration and taken by tens of thousands of women, with minimal side effects.


'/>"/>

Contact: Catherine Kolf
ckolf@jhmi.edu
443-287-2251
Johns Hopkins Medicine
Source:Eurekalert

Related medicine news :

1. Carey Danis & Lowe Lawyers Review Potential Impact of Transvaginal Mesh Settlement
2. Diet Doc Hormone Diets & Weight Loss Plans Announces New Diet Plans, Providing Fast Weight Loss Now Found to Potentially Help Prevent Pancreatic Cancer
3. Mount Sinai Researchers Identify Mechanisms and Potential Biomarkers of Tumor Cell Dormancy
4. UNC child neurologist finds potential route to better treatments for Fragile X, autism
5. Potential Medtronic Infusion Pump Malfunction Claims: Resource4thePeople Attorneys Now Providing Consulations
6. Potential new drug for some patients with treatment-resistant lung cancer
7. Targeted investigational therapy potential to overcome crizotinib resistance in lung cancers
8. Potential new drug effective in breast cancer and melanoma resistant to targeted therapies
9. New Research Shows Wild Blueberries Have Potential to Improve Heart Health
10. Macrophage-derived mediators may have potential as biomarkers for urinary stone risk
11. Repurposed antidepressants have potential to treat small-cell lung cancer
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/29/2016)... ... April 29, 2016 , ... Melanoma is the deadliest type of skin cancer. Although ... the majority of skin cancer deaths. More than 10,000 people are expected to die of ... is 62, it is the one of the most commonly diagnosed cancers in young women. ...
(Date:4/29/2016)... ... , ... For those who skip meals occasionally (which is pretty much everyone), ... many new lifestyle diet tips offered by nutritionists Pam Bonney and Priya Lawrence of ... show. Bonny and Lawrence noted that because proper nutrition, including water, provides energy during ...
(Date:4/29/2016)... ... April 29, 2016 , ... CURE Media ... on patients with cancer, today announced that Lynne Malestic, RN, of Eisenhower Lucy ... CURE® Extraordinary Healer® for Oncology Nursing , which honors nurses who have dedicated ...
(Date:4/29/2016)... ... April 29, 2016 , ... International Dehydrated Foods, Inc. (IDF™) will attend and ... at the Doubletree by Hilton Hotel in Oak Brook, Illinois. The two-day event is ... for protein ingredients. , At the seminar, IDF™ will offer samples of its Savory ...
(Date:4/29/2016)... ... April 29, 2016 , ... Intellitec Solutions ... May 16th to 18th at the Broward County Convention Center. The event is ... collaborate on best practices in public facility management. Intellitec Solutions will highlight their ...
Breaking Medicine News(10 mins):
(Date:4/28/2016)... YORK , April 28, 2016  The blood ... 275 million dollars, according to Kalorama Information and The ... typing, immunoassays and nucleic acid testing.  The healthcare research ... made progress in developing blood collection stations and in ... made in Kalorama Information,s report, Blood Testing ...
(Date:4/28/2016)... , Net Sales of $1.90 billion represent an increase ... period, and an increase of 1.2% on an adjusted pro ... first quarter were $0.52 reported, a decrease of 47.5% from ... 29.9% over the prior year period , The Company ... Zimmer Biomet Holdings, Inc. (NYSE and SIX: ZBH) ...
(Date:4/28/2016)... JERUSALEM , April 28, 2016 ... ), a clinical-stage pharmaceutical company focused on the development of ... participate in the upcoming PIONEERS 2016 conference, presented by ... 5, 2016 in New York . ... overview at the conference. Presentation Details:   ...
Breaking Medicine Technology: