Navigation Links
Cold winters freezing out breast cancer treatment
Date:4/18/2013

LONDON, ON For women diagnosed with a form of breast cancer known as estrogen receptor positive (ER+) breast cancer, tamoxifen is an essential drug used in the treatment and prevention of recurring breast cancer. Currently, tamoxifen is used in a one-size-fits-all approach where the same dose is prescribed for every patient. New research at Lawson Health Research Institute has found that in addition to patient-specific genetic factors, lack of exposure to vitamin D during the long winter months affects the body's ability to metabolize the drug.

The findings, which have been reported in the journal Breast Cancer Research and Treatment, are the first to identify this seasonal effect. Dr. Richard Kim, who is a physician at London Health Sciences Centre (LHSC) and holds the Wolfe Medical Research Chair in Pharmacogenomics at Western University, reports that during the winter months nearly 30 percent of patients are at risk for less than optimal level of the active form of tamoxifen, called endoxifen, and therefore may not benefit as much from the therapy.

In the liver, tamoxifen is converted to the active form of the drug called endoxifen by a protein called CYP2D6. "We know that endoxifen is nearly 100 times more potent against the estrogen receptor relative to tamoxifen," says Dr. Kim. "Our research has shown that patients with normal CYP2D6 activity can easily convert tamoxifen to endoxifen, whereas patients with no CYP2D6 activity have a significantly limited ability to convert tamoxifen to endoxifen."

In addition to the seasonal effect, Dr. Kim found that the simultaneous use of a common antidepressant can also substantially lower the body's ability to metabolize endoxifen levels. "Patients who are either partly or completely deficient in CYP2D6 and who are prescribed the SSRI class of antidepressants are at major risk for subtherapeutic endoxifen levels," says Dr. Kim.

With nearly 10 percent of the population completely lacking CYP2D6 enzymatic activity, these findings have important clinical applications. "Our most recent findings are important additions to the pool of data we already have on tamoxifen therapy," says Dr. Kim. "These new clinical and genetic markers can aid physicians to better identify patients who will benefit from tamoxifen, as well as those patients at risk for suboptimal benefit."


'/>"/>

Contact: Robert DeLaet
robert.delaet@lawsonresearch.com
519-685-8500 x75616
Lawson Health Research Institute
Source:Eurekalert

Related biology news :

1. Duck-billed dinosaurs endured long, dark polar winters
2. Extreme winters impact fish negatively
3. Freezing nerves knocks pain out cold
4. Protein jailbreak helps breast cancer cells live
5. Breast cancer risk gene discovery fast tracked by new technology
6. A new breast cancer susceptibility gene
7. Mechanism found connecting metastatic breast cancer and arthritis
8. Detecting breast cancers fingerprint in a droplet of blood
9. Researchers identified a protein useful in predicting the risk of pulmonary metastases in breast cancer patients
10. High levels of TRAIL protein in breast milk might contribute to anticancer activity
11. Fourth IMPAKT Breast Cancer Conference
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/15/2016)... , March 15, 2016 ... report published by Transparency Market Research "Digital Door Lock Systems ... Forecast 2015 - 2023," the global digital door lock systems ... Mn in 2014 and is forecast to grow at a ... of micro, small and medium enterprises (MSMEs) across the world ...
(Date:3/11/2016)... , March 11, 2016 http://www.apimages.com ) ... Cross reference: Picture is available at AP Images ( http://www.apimages.com ) ... DERMALOG will be used to produce the new refugee identity cards. ... biometric innovations, at CeBIT in Hanover next ... from DERMALOG will be used to produce the new refugee identity ...
(Date:3/9/2016)... , March 9, 2016 This BCC Research ... states of the RNA Sequencing (RNA Seq) market for ... as instruments, tools and reagents, data analysis, and services. ... segments of the RNA-Sequencing market such as RNA-Sequencing tools ... the main factors affecting each segment and forecast their ...
Breaking Biology News(10 mins):
(Date:4/27/2016)... ... , ... The Pittcon Organizing Committee is pleased to announce that Charles “Chuck” ... of Committee since 1987. Since then, he has served in a number of key ... for both the program and exposition committees. In his professional career, Dr. Gardner is ...
(Date:4/27/2016)... ... April 27, 2016 , ... The Board of ... appointment of John Tilton as Chief Commercial Officer.  Mr. Tilton joined Biohaven from ... founding commercial leaders responsible for the commercialization of multiple orphan drug indications. ...
(Date:4/27/2016)... (PRWEB) , ... April 27, 2016 , ... Global ... the GSCG Advisory Board. Ross is the founder of GSCG affiliate Kimera Labs in ... Miami, where he studied hematopoietic stem cell transplantation for hematologic disorders and the suppression ...
(Date:4/26/2016)... ANGELES, Calif. (PRWEB) , ... April 27, 2016 ... ... Angeles office of Lewis Roca Rothgerber Christie LLP as an associate in the ... prosecuting U.S. and international electrical, mechanical and electromechanical patent applications. He has an ...
Breaking Biology Technology: