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:5/27/2016)... ... May 27, 2016 , ... Aimed at ... inspiring human interest stories, courtesy of leaders in the nursing and health care ... industry, from leading advocates and associations—namely Jones & Bartlett Learning. , Jones & ...
(Date:5/27/2016)... Wis. (PRWEB) , ... May 27, 2016 , ... ... $90,000 in scholarships to students studying complementary medicine. Allison Outerbridge is this year’s ... accepted her award on May 18 at the university’s Student Leadership Awards ceremony. ...
(Date:5/26/2016)... ... , ... Despite last week’s media reports hinting at a June rate hike ... March 2017 for an interest rate increase, according to Rajeev Dhawan of the Economic ... Federal Open Market Committee (FOMC) dot charts are of interest to the press for ...
(Date:5/26/2016)... ... , ... W.S. Badger Co. Inc ., the maker of certified organic ... Works Award for its use of effective workplace strategies to increase business and employee ... by the Families and Work Institute (FWI) and the Society for Human Resource Management ...
(Date:5/26/2016)... ... 26, 2016 , ... Intalere, the healthcare industry leader in ... inaugural Member Conference at the Paris Hotel in Las Vegas, Nev., May 17-20, ... America’s healthcare providers. , The conference was highlighted by the announcement of the ...
Breaking Medicine News(10 mins):
(Date:5/30/2016)... , May 30, 2016 - DCGI grants ... due to Buerger,s disease - Stempeucel® becomes 5th off-the-shelf ... in the world - Buerger,s Disease (also known as ... India and Globally - Prevalence of Buerger,s ... and 2 per 10,000 persons in the European Community & ...
(Date:5/27/2016)... India , May 27, 2016 ... the instances of hypertension is driving ambulatory blood pressure ... lose their elasticity and their ability to respond to ... pressure. This condition can lead to various cardiovascular disorders ... peripheral vascular disease. These diseases are growing in prevalence ...
(Date:5/26/2016)... , May 26, 2016 According to ... Waste Management Market - U.S. Industry Analysis, Size, Share, Growth, ... market in the U.S. was valued at US$ 5.89 Bn ... of 3.4% from 2015 to 2023 to reach US$ 7.99 ... of current and emerging needle free drug delivery devices and ...
Breaking Medicine Technology: