Posts Tagged ‘national’

Soy supplementation adversely effects expression of breast cancer-related genes

The impact of soy consumption on breast cancer prevention and treatment is not clear although many women believe soy supplementation is beneficial based primarily on results from epidemiological studies. Moshe Shike, M.D., from the Department of Medicine at Memorial Sloan-Kettering Cancer Center and Weill Cornell Medical College in New York, NY, and colleagues conducted a randomized placebo-controlled study of the effects of soy supplementation on gene expression and markers of breast cancer risk among women diagnosed with invasive breast cancer. The study, run between 2003 and 2007 at Memorial Sloan-Kettering, enrolled a total of 140 patients who were randomized to either soy supplementation (soy protein) or placebo (milk protein), which lasted from the initial surgical consultation to the day before surgery (range=7-30 days). Tumor tissues from the diagnostic biopsy (pre-treatment) and at the time of resection (post-treatment) were then analyzed. They observed changes in several genes that promote cell cycle progression and cell proliferation among women in the soy group.

The authors conclude, “These data raise concern that soy may exert a stimulating effect on breast cancer in a subset of women.”

In an accompanying editorial, V. Craig Jordan, O.B.E., D.Sc., Ph.D., FMedSci, from the Department of Oncology at the Georgetown University Lombardi Comprehensive Cancer Center, Washington, DC, discusses how timing of soy supplementation is critical and reviews the evidence in the literature on phytoestrogens, which are contained in soy, and their known action in breast cancer. He writes, the study by Shike et al. “…illustrates the dangers of phytoestrogen consumption too soon, around menopause, but the biology of estrogen in estrogen-deprived conditions suggests that phytoestrogen could have benefit a decade after menopause.” He cautions that appropriate doses of soy and timing of consumption are critical considerations.

source : http://www.sciencedaily.com/releases/2014/09/140904183725.htm

Disparities persist in early-stage breast cancer treatment

The study, to be presented at the 2014 Breast Cancer Symposium, finds that those barriers that still exist are socio-economic, rather than medically-influenced. Meeghan Lautner, M.D., formerly a fellow at MD Anderson, now at The University of Texas San Antonio, will present the findings.

BCT for early stage breast cancer includes breast conserving surgery, followed by six weeks of radiation. It has been the accepted standard of care for early stage breast cancer since 1990 when randomized, prospective clinical trials confirmed its efficacy — leading to the National Institute of Health issuing a consensus statement. Yet, a number of patients still opt for a mastectomy. In hopes of ultimately democratizing care, it was important to look at surgical choices made by women and their association with disparities, explains Isabelle Bedrosian, M.D., associate professor, Surgical Oncology at MD Anderson.

“What’s particularly novel and most meaningful about our study is that we looked at how the landscape has changed over time,” says Bedrosian, the study’s senior author. “We hope this will help us understand where we are and are not making progress, as well as identify the barriers we need to overcome to create equity in the delivery of care for our patients.”

For the retrospective, population-based study, the MD Anderson team used the National Cancer Database, a nation-wide outcomes registry of the American College of Surgeons, the American Cancer Society and the Commission on Cancer that captures approximately 70 percent of newly-diagnosed cases of cancer in the country. They identified 727,927 women with early-stage breast cancer, all of whom were diagnosed between 1998 and 2011 and had undergone either BCT or a mastectomy.

Overall, the researchers found that BCT rates increased from 54 percent in 1998 to 59 percent in 2006, and stabilized since then. Adjusting for demographic and clinical characteristics, BCT use was more common in women: age 52-61 compared to younger or older patients; with a higher education level and median income; with private insurance, compared to those uninsured; and who were treated at an academic medical center versus a community medical center.

Geographically, BCT rates were higher in the Northeast than in the South, and in those women who lived within 17 miles of a treatment facility compared to those who lived further away.

An important question to then ask, says Bedrosian, was to compare barriers for women receiving BCT in 1998 to 2011 — and understand how have those barriers changed. The researchers found that, overall, usage of BCT has dramatically increased across all demographic and clinical characteristics, however, significant disparities related to insurance, income and distance to a treatment facility still exist.

Bedrosian is gratified to see that in the areas where physicians and the medical field can make a direct impact — such as geographic distribution and practice type — disparities have equalized over time. However, she notes that factors outside the influence of the medical field, such as insurance type, income and education, still remain. Of great interest is the insurance disparity, says Bedrosian.

“Now with healthcare exchanges providing new insurance coverage options, will we rectify the disparity and overall increase BCT use? We will have wait to see,” she says.

Bedrosian hopes that health policy makers will take note of the findings and barriers related to women receiving BCT and make appropriate changes to democratize care.

source : http://www.sciencedaily.com/releases/2014/09/140904103338.htm

Research reveals mechanism behind cell protein remodeling

According to the National Cancer Institute, more than a third of all human cancers are driven by mutations in the Ras family of genes. When Ras is activated, it promotes tumor growth but also activates autophagy which helps to sustain that growth. These cancers remodel proteins using the cellular self-cannibalization process known as autophagy to capture and degrade intracellular proteins and protein-containing organelles. Since Ras-driven cancers often rely on autophagy for growth and survival, this raised the question: Is proteome remodeling by autophagy important, and if so, by what mechanism?

This question was answered in research published in the current online edition of Molecular Cell, by senior author Eileen White, PhD, associate director for basic science at the Cancer Institute of New Jersey, and colleagues. They compared the global proteome (all of the expressed proteins) of Ras-driven cancer cells where autophagy was present to those where autophagy was deficient.

In this latest study researchers found that autophagy affects a majority of the proteins in Ras-driven cancers, yet the process is highly selective as to which proteins are targeted. For instance, investigators found that autophagy eliminates proteins involved in non-essential pathways or those deemed toxic under stressful conditions. Meanwhile, autophagy-resistant proteins involved in pathways needed for stress survival and autophagy maintenance were spared. The authors say these sets of proteins can serve as biomarkers for monitoring autophagy in the clinical setting. The study also revealed that defects in the autophagy process caused accumulation of certain proteins that prompted activation of an immune response in cancer cells and led to cell death.

“This remodeling process of the cell proteome by autophagy is an important immune-suppressive survival mechanism for Ras-driven cancers, and inhibiting autophagy can provide a means to target these aggressive cancers,” notes White, who is also a distinguished professor of molecular biology and biochemistry at Rutgers School of Arts and Sciences.

source : http://www.sciencedaily.com/releases/2014/08/140828135240.htm