Some Cancers More Likely Among Taller Women

What You Need to Know:  A new study has found an increased risk for certain types of cancers in taller women.

Background: While obesity has long been named as a risk factor for cancer, a new study published in Cancer Epidemiology, Biomarkers & Prevention that adjusts for various factors including age and weight, has found an increased risk for certain types of cancers in taller women.

The Evidence: The study, which included 20,298 postmenopausal women, found that for every 10-centimeter (3.94 inches) increase in height, there was a 13% increase in the risk of developing certain cancers, including, breast, colon, endometrium, kidney, ovary, rectum, thyroid, multiple myeloma and melanoma. The most surprising finding for researchers was that weight seems to be a lower risk factor than previously assumed.

“We did examine variation in risk and there was no variation of levels of risk by weight,” says senior author Thomas Rohan, PhD, MD, chairman and professor of the department of epidemiology and population health at Albert Einstein College of Medicine.

Since you can’t really do anything about your height, what does this mean to tall women? Nothing specifically, says Dr. Rohan. He says the purpose of the study was not to make clinical recommendations and there was no thought of cancer screening or diagnosis implied in the study. Rather, the researchers were merely to try to add to the existing research into the biology of cancer development.

“We have been aware of some reports in the literature about the link between cancer and height, and we thought we could make a contribution to that research,” says Dr. Rohan.

In other words, don’t try to stunt your daughter’s growth so that her cancer risk is reduced when she is in her 70s.

Lead researcher Geoffrey Kabat, PhD, MS, a senior epidemiologist at Albert Einstein College of Medicine, noted that cancer is a result of processes having to do with growth, so hormones or other growth factors that influence height may also influence long-term cancer risk. The study also notes that height should not be thought of as a risk factor, but rather as a marker for exposures that may influence cancer risk. In other words, there are so many things that effect growth, that it’s almost beyond anyone’s ability to control.

The take-home message is not to panic, but to just appreciate one more small step in the ongoing quest to try to figure out exactly what makes cancer tick. I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad: Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: http://www.prevention.com/health/health-concerns/scary-link-between-height-and-cancer-risk

 

 

High Cholesterol May Fuel Growth, Spread of Breast Cancer (In Mouse Models)

Spacefill model of the Cholesterol molecule
Spacefill model of the Cholesterol molecule (Photo credit: Wikipedia)

A byproduct of cholesterol functions like the hormone estrogen to fuel the growth and spread of the most common types of breast cancers, researchers at the Duke Cancer Institute report. The researchers also found that anti-cholesterol drugs such as statins appear to diminish the effect of this estrogen-like molecule.

Published in the Nov. 29, 2013, edition of the journal Science, the findings are early, using mouse models and tumor cells. But the research for the first time explains the link between high cholesterol and breast cancer, especially in post-menopausal women, and suggests that dietary changes or therapies to reduce cholesterol may also offer a simple, accessible way to reduce breast cancer risk.

“A lot of studies have shown a connection between obesity and breast cancer, and specifically that elevated cholesterol is associated with breast cancer risk, but no mechanism has been identified,” said senior author Donald McDonnell, Ph.D., chair of the Department of Pharmacology and Cancer Biology at Duke. “What we have now found is a molecule — not cholesterol itself, but an abundant metabolite of cholesterol — called 27HC that mimics the hormone estrogen and can independently drive the growth of breast cancer.”

The hormone estrogen feeds an estimated 75 percent of all breast cancers. In a key earlier finding from McDonnell’s lab, researchers determined that 27-hydroxycholesterol — or 27HC — behaved similarly to estrogen in animals.

For their current work, the researchers set out to determine whether this estrogen activity was sufficient on its own to promote breast cancer growth and metastasis, and whether controlling it would have a converse effect.

Using mouse models that are highly predictive of what occurs in humans, McDonnell and colleagues demonstrated the direct involvement of 27HC in breast tumor growth, as well as the aggressiveness of the cancer to spread to other organs. They also noted that the activity of this cholesterol metabolite was inhibited when the animals were treated with antiestrogens or when supplementation of 27HC was stopped.

The studies were substantiated using human breast cancer tissue. An additional finding in the human tissue showed a direct correlation between the aggressiveness of the tumor and an abundance of the enzyme that makes the 27HC molecule. They also noted that 27HC could be made in other places in the body and transported to the tumor.

“The worse the tumors, the more they have of the enzyme,” said lead author Erik Nelson, Ph.D., a post-doctoral associate at Duke. Nelson said gene expression studies revealed a potential association between 27HC exposure and the development of resistance to the antiestrogen tamoxifen. Their data also highlights how increased 27HC may reduce the effectiveness of aromatase inhibitors, which are among the most commonly used breast cancer therapeutics.

“This is a very significant finding,” McDonnell said. “Human breast tumors, because they express this enzyme to make 27HC, are making an estrogen-like molecule that can promote the growth of the tumor. In essence, the tumors have developed a mechanism to use a different source of fuel.”

McDonnell said the findings suggest there may be a simple way to reduce the risk of breast cancer by keeping cholesterol in check, either with statins or a healthy diet. Additionally, for women who have breast cancer and high cholesterol, taking statins may delay or prevent resistance to endocrine therapies such as tamoxifen or aromatase inhibitors.

The next steps for research include clinical studies to verify those potential outcomes, as well as studies to determine if 27HC plays a role in other cancers, McDonnell said.

I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad:  Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: Duke University Medical Center (2013, November 28). High cholesterol fuels growth, spread of breast cancer. ScienceDaily. Retrieved November 28, 2013, from http://www.sciencedaily.com­/releases/2013/11/131128141357.htm