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Two recent studies link low vitamin D levels with more aggressive cancers: aggressive prostate cancer in men and more aggressive breast cancers (in mice and women). Researchers generally advise people to take 1000 to 2000 international units per day of vitamin D3 to maintain normal blood levels of of more than 30 nanograms/milliliter. The best source of vitamin D is sunlight, which is why vitamin D is frequently called the sunshine vitamin.

From Science Daily:  Low vitamin D predicts aggressive prostate cancer

A new study provides a major link between low levels of vitamin D and aggressive prostate cancer. Northwestern Medicine research showed deficient vitamin D blood levels in men can predict aggressive prostate cancer identified at the time of surgery.

"Vitamin D deficiency may predict aggressive prostate cancer as a biomarker," said lead investigator Dr. Adam Murphy, an assistant professor of urology at Northwestern University Feinberg School of Medicine and a Northwestern Medicine urologist. "Men with dark skin, low vitamin D intake or low sun exposure should be tested for vitamin D deficiency when they are diagnosed with an elevated PSA or prostate cancer. Then a deficiency should be corrected with supplements."

Aggressive prostate cancer is defined by whether the cancer has migrated outside of the prostate and by a high Gleason score. A low Gleason score means the cancer tissue is similar to normal prostate tissue and less likely to spread; a high one means the cancer tissue is very different from normal and more likely to spread. The study was part of a larger ongoing study of 1,760 men in the Chicago area examining vitamin D and prostate cancer. The current study included 190 men, average age of 64, who underwent a radical prostatectomy to remove their prostate from 2009 to 2014.

Of that group, 87 men had aggressive prostate cancer. Those with aggressive cancer had a median level of 22.7 nanograms per milliliter of vitamin D, significantly below the normal level of more than 30 nanograms/milliliter. The average D level in Chicago during the winter is about 25 nanograms/milliliter, Murphy noted....The Institute of Medicine recommends 600 international units of D per day, but Murphy recommends Chicago residents get 1,000 to 2,000 international units per day.

From Medical Xpress:  Vitamin D deficiency contributes to spread of breast cancer in mice, study finds

Breast tumors in laboratory mice deficient in vitamin D grow faster and are more likely to metastasize than tumors in mice with adequate levels of vitamin D, according to a preliminary study by researchers at the Stanford University School of Medicine.The research highlights a direct link between circulating vitamin D levels and the expression of a gene called ID1, known to be associated with tumor growth and breast cancer metastasis.

The finding builds upon several previous studies suggesting that low levels of vitamin D not only increase a person's risk of developing breast cancer, but are also correlated with more-aggressive tumors and worse prognoses. Although the research was conducted primarily in mice and on mouse cells, the researchers found in a study of 34 breast cancer patients that levels of circulating vitamin D were inversely correlated with the expression levels of ID1 protein in their tumors, and they confirmed that a vitamin D metabolite directly controls the expression of the ID1 gene in a human breast cancer cell line.

Once ingested or made by the body, vitamin D is converted through a series of steps into its active form, calcitriol. Calcitriol binds to a protein in cells called the vitamin D receptor, which then enters the cell's nucleus to control the expression of a variety of genes, including those involved in calcium absorption and bone health.

In the new study, Williams and Aggarwal investigated whether vitamin D levels affected the metastatic ability of mouse breast cancer cells implanted into the mammary fat pad of laboratory mice. One group of 10 mice was first fed a diet lacking in the vitamin for 10 weeks; the other 10 received a normal dose in their food. Mice fed a diet deficient in vitamin D developed palpable tumors an average of seven days sooner than their peers, and after six weeks of growth those tumors were significantly larger in size than those in animals with adequate vitamin D levels.

Reading this recent study, I was struck by how the results are evidence for eating sulforaphane containing foods, such as kale, cauliflower, brussels sprouts, broccoli, and cabbage for health and preventing cancer (due to anti-tumor activity). It is debatable whether it is support for taking supplements (here a sulforaphane supplement called BSE), even though the researchers were testing the supplement. Seven days of taking a supplement without "serious adverse events" (but they did have minor ones such as "mild abdominal discomfort") is too short a length of time for any support for a product. The real test would be seeing what health effects, both positive and negative, are after a year or two of taking the supplement.

Numerous other studies have found that eating foods are linked to good health, while taking supplements are linked to various health problems. Some scientists speculate that it's because the doses in supplements are too high - that they're much higher than what is found in foods. Also, supplements may be missing important nutrients that are found in foods. Bottom line: eat real foods for health and and cancer prevention, including several servings a week of cruciferous vegetables (cauliflower, cabbage, garden cress,bok choy, broccoli, brussels sprouts and similar green leaf vegetables). From Futurity:

Can A Broccoli Sprout Pill Fight Cancer?

A compound in broccoli sprouts may not only help prevent cancer but also treat itSulforaphane is found in vegetables such as kale, cauliflower, and cabbage—and in particularly high concentrations in young broccoli sprouts. Sulforaphane also is available as a dietary supplement called BSE.

Researchers at the Texas A&M Health Science Center Institute of Biosciences and Technology, along with collaborators in Oregon, had previously found that sulforaphane could inhibit colon and prostate cancer cells in the laboratory. They’ve now shown that it seems to help humans as well. A paper published in the journal Clinical Epigenetics hints at the biological pathways involved and suggests BSE is generally safe.

“We have not seen any serious adverse events in healthy volunteers who consumed BSE pills for seven days,” says Praveen Rajendran, an assistant professor at Texas A&M University, although some people did experience mild abdominal discomfort.

In a separate clinical study, 28 human volunteers over the age of 50, who were undergoing routine colonoscopies, were surveyed for their cruciferous vegetable-eating habits. When their colon biopsies were examined, those who ate more servings were found to have higher levels of expression of the tumor suppressor gene p16 than those who ate few or no cruciferous vegetables.

This effect on p16 held even for people who didn’t eat these vegetables every single day, which may seem strange, as a single serving of sulforaphane is generally cleared from the body in less than 24 hours. “This hints at the possibility that epigenetic mechanisms are initially triggered by sulforaphane and its metabolites, and downstream mechanisms could be sustained, at least in the short-term, even after compounds are eliminated from the body.” In other words, eating vegetables containing sulforaphane may change your genes and help your body fight tumor growth.

However, it’s not all good news. In animal models, sulforaphane was shown to generally inhibit the development of colon cancer, but it’s a bit of a two-edged sword. Sulforaphane induces a protein called Nrf2, which has beneficial antioxidant and detoxifying effects—and is obviously good for fighting cancer. Later in the development of cancer, though, Nrf2 can also have a role in tumor growth and can even enhance the buildup of plaque in the arteries.

Data from 2 huge studies was analyzed and found that vigorous exercise and other healthy habits seems to cut the chance of developing aggressive and lethal prostate cancer up to 68 percent in men over 60. The beneficial lifestyle habits are: weekly vigorous exercise or activity to the point of sweating, at least 7 servings of tomatoes a week, at least one serving of fatty fish per week, reduced intake of processed meat, and being a long-term non-smoker.

Interestingly, vigorous activity or exercise to sweating - ideally up to 3 hours a week - showed the biggest association with a 34 % reduced risk of aggressive prostate cancer.

From Science Daily: Working up a sweat may protect men from lethal prostate cancer

A study that tracked tens of thousands of midlife and older men for more than 20 years has found that vigorous exercise and other healthy lifestyle habits may cut their chances of developing a lethal type of prostate cancer by up to 68 percent.

While most prostate cancers are "clinically indolent," meaning they do not metastasize and are nonlife-threatening, a minority of patients are diagnosed with aggressive disease that invades the bone and other organs, and is ultimately fatal. Lead author Stacey Kenfield, ScD, of UCSF, and a team of researchers at UCSF and Harvard, focused on this variant of prostate cancer to determine if exercise, diet and smoke-free status might have life-saving benefits.

In the study, published in the Journal of the National Cancer Institute, the researchers analyzed data from two U.S. studies: the Health Professionals Follow-Up Study that tracked more than 42,000 males ages 40 to 75, from 1986 to 2010; and a second, the Physicians' Health Study that followed more than 20,000 males ages 40 to 84, from 1982 to 2010.

To gage the effects of lifestyle habits, the researchers developed a score based on the results of the health professionals survey, then applied it to the physicians' study. They assigned one point for each affirmative response to questions about regular intense exercise that induced sweating, body mass index (BMI) under 30, tobacco-free status for a minimum of 10 years, high intake of fatty fish, high intake of tomatoes and low intake of processed meat.

The researchers identified 576 cases of lethal prostate cancer in the health professionals' group and 337 cases in the physicians' group. Participants with 5 to 6 points in the health professionals' group had a 68 percent decreased risk of lethal prostate cancer and a 38 percent decreased risk was observed in the physicians' group for the same comparison.

"We estimated that 47 percent of lethal prostate cancer cases would be prevented in the United States if men over 60 had five or more of these healthy habits," said Kenfield, assistant professor in the Department of Urology at UCSF Medical Center, and formerly of the Department of Medicine at Harvard Medical School in Boston, where the study was initiated.

"It's interesting that vigorous activity had the highest potential impact on prevention of lethal prostate cancer. We calculated the population-attributable risk for American men over 60 and estimated that 34 percent of lethal prostate cancer would be reduced if all men exercised to the point of sweating for at least three hours a week," Kenfield said.

The researchers also calculated that lethal prostate cancer among American men over 60 would be cut by 15 percent if they consumed at least seven servings of tomatoes per week and that 17 percent would be spared this diagnosis if they consumed at least one serving of fatty fish per week. Reducing intake of processed meats would cut the risk by 12 percent, they reported. In contrast, the population-attributed risk for smoking was 3 percent, largely because the majority of older American men are long-term nonsmokers.

A report by 3 prominent specialists (including Gilbert Welch - who has been discussed in earlier posts) about trends in metastatic breast and prostate cancer came out today in the New England Journal of Medicine. The biggest finding was that mammograms have not cut the rate of metastatic breast cancer. Mammography screening is based on the hope that cancer that is detected in an early, localized phase can then be treated more easily and that it would reduce the numbers of metastastic cancers (that spread to lymph nodes and to more distant organs) that eventually kill. However, this has not happened.The incidence of metastatic breast cancer has been stable since 1975, and the average age of diagnosis among women older than 40 is still 63.7 years . The authors theorize that "breast cancer is a systemic disease by the time it's detectable". From Medical Xpress:

Study: Mammograms haven't cut rate of advanced breast cancer

A new report raises fresh questions about the value of mammograms. The rate of cancers that have already spread far beyond the breast when they are discovered has stayed stable for decades, suggesting that screening and early detection are not preventing the most dangerous forms of the disease. The report, in Thursday's New England Journal of Medicine, is by three prominent cancer specialists and is based on federal statistics going back to the 1970s.

"We're undergoing what I think for the public is a very confusing debate" about screening, but it's really "a course correction" prompted by more awareness of its risks and benefits to various groups of women, said Dr. H. Gilbert Welch, a health policy expert at Dartmouth Medical School. "All they heard for years was, 'there are only benefits.'" He is the lead author of the report, co-written with Dr. David Gorski of Wayne State University School of Medicine in Detroit and Dr. Peter Albertsen of the University of Connecticut Health Center in Farmington.

"Screening offers hope that cancer can be detected in an early, localized phase when it's more amenable to treatment," they write, but that assumes that cancer starts in one place, grows and then spreads. If that was always true, screening would reduce the rate of advanced cancers. And that has not happened. The rate of breast cancers detected at an advanced stage has been stable since 1975, despite wide use of mammography since the 1980s. The average age of women diagnosed with cancer also has remained around 63, another sign cancers are not being found sooner.

The trends suggest that some breast cancers are already "systemic" or widely spread from the start, and that finding them sooner has limited impact. "Screening mammography has been unable to identify those bad cancers, destined to become metastatic, at an earlier stage. That doesn't say mammography doesn't help less aggressive cancers," but those are less likely to prove deadly, Welch said.

Dr. Barnett Kramer, a screening expert at the National Cancer Institute, said the report shows the limitations of mammography. "I wouldn't want to say it has had no effect but it certainly has not lived up to the anticipated effect," he said. For every tumor detected early because of mammography, "you would hope to see ... an equal reduction in metastatic disease, and that has not occurred."

The situation is very different with prostate cancer. The rate of advanced cases of that disease has been cut in half since screening with PSA blood tests came into wide use around 1988, and the average age at which men are diagnosed has fallen—from 72 to 70, the authors write. However, this does not prove PSA testing is good. Shifting the stage at which a disease is diagnosed is "only the first step for successful screening," which also has to save lives to be worthwhile, Welch said. "Just because you find something earlier doesn't mean you can change its course."

Again, Kramer agreed. Prostate screening, "when put to a definitive test, did not show a clear reduction in prostate cancer mortality" in large, rigorously done trials, he said. The government task force recommends against PSA testing, and says its risks outweigh its benefits for most men.

"Screening is a close call," Welch said. "My guess is few people are helped" by prostate or breast cancer screening while many are harmed by false alarms that trigger unnecessary tests and treatments, he said.

The original report, which also includes a discussion on prostate cancer and the PSA test, in the New England Journal of Medicine:  Trends in Metastatic Breast and Prostate Cancer — Lessons in Cancer Dynamics

The issue of overdiagnosis and overtreatment has recently been in the news, especially when discussing breast cancer, prostate cancer, and thyroid cancer. Meaning too much unnecessary treatment with harms, when the best approach would have been to do nothing, as studies have suggested or actually shown. Now here is an article in Medscape suggesting that rather than be quick to operate or treat, the best approach for nearly 70% of prostate cancers may be just "watching".

The U.S. Preventive Task Force, which analyzes the value of screening tests, in May 2012 recommended AGAINST routine prostate-specific antigen (PSA)-based screening for prostate cancer for all age groups. According to them, studies do not show that benefits of routine screening of asymptomatic prostate cancer and the resulting treatment outweigh the harms of treatment (e.g., surgical complications including death from surgery, erectile dysfunction, urinary incontinence, bowel dysfunction, and bladder dysfunction), or that prostate cancer treatment even reduces mortality (deaths).

They point out that: "There is convincing evidence that PSA-based screening programs result in the detection of many cases of asymptomatic prostate cancer. There is also convincing evidence that a substantial percentage of men who have asymptomatic cancer detected by PSA screening have a tumor that either will not progress or will progress so slowly that it would have remained asymptomatic for the man's lifetime. The terms "overdiagnosis" or "pseudo-disease" are used to describe both situations." (NOTE: others have argued against this recommendation)

When reading the full Medscape article, it was pointed out that in the study being discussed, one person who was offered active surveillance but declined and was treated with an immediate radical prostatectomy, still died of metastatic prostate cancer. This was an example of a case where when the disease is truly aggressive, it may have spread "like a bird" throughout the body (in Dr. H. Gilbert Welch's terms in his books Overdiagnosed and Less Medicine, More Health) from the very beginning, and may be unstoppable no matter what is done.

I have also noticed reading other prostate cancer studies that a certain percentage of prostate cancers regress from the point of diagnosis (the PSA test and biopsy). In other words, researchers are finding that cancer can have different paths: regresses, stays the same, grows slowly (and can be treated when symptoms appear), or grows very quickly and is so aggressive and unstoppable that it goes through the body "like a bird". And we don't know which will be the aggressive ones when we first find them, thus the controversies over what to do: screen or not?, and treat or not?  ...continue reading "Nearly 70% of Prostate Cancers Can Just Be Watched?"

Prostate cancer diagnosis is scary enough, but knowing that dietary changes can increase favorable odds is good. Once again a Mediterranean style diet  or "healthy diet"(whole grains, fruits, vegetables, seeds, nuts, legumes, olive oil, and fish) is beneficial, while a Western diet (highly processed foods, red meat, processed meat, and dairy) is linked to higher rates of death. This study was from the Harvard School of Public Health and followed male physicians for an average of 14 years after prostate cancer diagnosis. From Science Daily:

Western diet may increase risk of death after prostate cancer diagnosis

After a prostate cancer diagnosis, eating a diet higher in red and processed meat, high-fat dairy foods, and refined grains--known as a Western diet--may lead to a significantly higher risk of both prostate cancer-related mortality and overall mortality compared with eating a diet rich in vegetables, fruits, fish, whole grains, legumes, and healthy oils, according to a new study from Harvard T.H. Chan School of Public Health.

The study, which appears online June 1, 2015 in the journal Cancer Prevention Research, offers insight on how diet may help improve survivorship for the nearly three million men living with prostate cancer in the U.S."There is currently very little evidence to counsel men living with prostate cancer on how they can modify their lifestyle to improve survival. Our results suggest that a heart-healthy diet may benefit these men by specifically reducing their chances of dying of prostate cancer," said Jorge Chavarro, assistant professor of nutrition and epidemiology at the Harvard Chan School and senior author of the study.

Researchers examined health and diet data from 926 men participating in the Physicians' Health Study I and II who were diagnosed with prostate cancer. They followed the men for an average of 14 years after their diagnosis, grouping them into quartiles according to whether they followed a Western dietary pattern or a "prudent" (higher consumption of vegetables, fruits, fish, legumes, and whole grains) dietary pattern.

They found that men who ate mostly a Western diet (those in the highest quartile of the Western dietary pattern) had two-and-a-half times higher risk of prostate cancer-related death--and a 67% increased risk of death from any cause--than those in the lowest quartile. Men who ate mostly a "prudent" diet had a 36% lower risk of death from all causes.

Great reasons to eat walnuts. Yes, this study was done in mice, but it (as supported by other research) should also apply to humans.From Medical Xpress:

'Tis the season to indulge in walnuts

Researchers at UC Davis and other institutions have found that diets rich in whole walnuts or walnut oil slowed prostate cancer growth in mice. In addition, both walnuts and walnut oil reduced cholesterol and increased insulin sensitivity. The walnut diet also reduced levels of the hormone IGF-1, which had been previously implicated in both prostate and breast cancer. The study was published online in the Journal of Medicinal Food. 

Davis and colleagues have been investigating the impact of walnuts on health for some time. A previous study found that walnuts reduced prostate tumor size in mice; however, there were questions about which parts of the nuts generated these benefits. 

In the current study, researchers used a mixture of fats with virtually the same fatty acid content as walnuts as their control diet. The mice were fed whole walnuts, walnut oil or the walnut-like fat for 18 weeks. The results replicated those from the previous study. While the walnuts and walnut oil reduced cholesterol and slowed prostate cancer growth, in contrast, the walnut-like fat did not have these effects, confirming that other nut components caused the improvements - not the omega-3s.

While the study does not pinpoint which combination of compounds in walnuts slows cancer growth, it did rule out fiber, zinc, magnesium and selenium. In addition, the research demonstrated that walnuts modulate several mechanisms associated with cancer growth.

"The energy effects from decreasing IGF-1 seem to muck up the works so the cancer can't grow as fast as it normally would," Davis said. "Also, reducing cholesterol means cancer cells may not get enough of it to allow these cells to grow quickly." In addition, the research showed increases in both adiponectin and the tumor suppressor PSP94, as well as reduced levels of COX-2, all markers for reduced prostate cancer risk.

Although results in mice don't always translate to humans, Davis said his results suggest the benefits of incorporating walnuts into a healthy diet. Other research, such as the PREDIMED human study, which assessed the Mediterranean diet, also found that eating walnuts reduced cancer mortality.

Still, Davis recommends caution in diet modification. "In our study the mice were eating the equivalent of 2.6 ounces of walnuts," he said. "You need to realize that 2.6 ounces of walnuts is about 482 calories. That's not insignificant, but it's better than eating a serving of supersized fries, which has 610 calories. In addition to the cancer benefit, we think you also get cardiovascular benefits that other walnut research has demonstrated.

Eating more tomatoes is doable, tastes delicious, and reduces prostate cancer risk! From Science Daily:

Fighting prostate cancer with tomato-rich diet

Men who eat over 10 portions a week of tomatoes have an 18 percent lower risk of developing prostate cancer, new research suggests. With 35,000 new cases every year in the UK, and around 10,000 deaths, prostate cancer is the second most common cancer in men worldwide. Rates are higher in developed countries, which some experts believe is linked to a Westernised diet and lifestyle.

To assess if following dietary and lifestyle recommendations reduces risk of prostate cancer, researchers at the Universities of Bristol, Cambridge and Oxford looked at the diets and lifestyle of 1,806 men aged between 50 and 69 with prostate cancer and compared with 12,005 cancer-free men.

The NIHR-funded study, published in the medical journal Cancer Epidemiology, Biomarkers and Prevention, is the first study of its kind to develop a prostate cancer 'dietary index' which consists of dietary components -- selenium, calcium and foods rich in lycopene -- that have been linked to prostate cancer. Men who had optimal intake of these three dietary components had a lower risk of prostate cancer.

Tomatoes and its products -- such as tomato juice and baked beans -- were shown to be most beneficial, with an 18 per cent reduction in risk found in men eating over 10 portions a week. This is thought to be due to lycopene, an antioxidant which fights off toxins that can cause DNA and cell damage. 

The researchers also looked at the recommendations on physical activity, diet and body weight for cancer prevention published by the World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR). Only the recommendation on plant foods -- high intake of fruits, vegetables and dietary fibre -- was found to be associated with a reduced risk of prostate cancer. 

The worrisome results are adding up for BPA and BPS. From Environmental Health News:

Miscarriage risk rises with BPA exposure, study finds

Women exposed to high levels of bisphenol A early in their pregnancy had an 83 percent greater risk of miscarriage than women with the lowest levels, according to new research. The scientists said their new study adds to evidence that low levels of the ubiquitous chemical, used to make polycarbonate plastic and found in some food cans and paper receipts, may affect human reproduction. The study involved 115 pregnant women who had visited a Stanford University fertility clinic within about four weeks of fertilization. The more BPA detected in the women’s blood, the higher their risk of miscarriage, according to the researchers.

“Couples suffering from infertility or recurrent miscarriages would be best advised to reduce BPA exposure because it has the potential to adversely affect fetal development,” wrote the scientists, led by Dr. Ruth Lathi, a Stanford University associate professor of obstetrics and gynecology. 

In 2005, a smaller study in Japan found that 45 women who had three or more first-trimester miscarriages had three times more BPA in their blood than 32 women with no history of pregnancy problems. 

From Science Daily:

BPA increases risk of cancer in human prostate tissue, study shows

Fetal exposure to a commonly used plasticizer found in products such as water bottles, soup can liners and paper receipts, can increase the risk for prostate cancer later in life, according to a study. Exposure of the fetus to BPA in utero is of particular concern, because the chemical, which mimics the hormone estrogen, has been linked to several kinds of cancer, including prostate cancer, in rodent models. The new findings show that human prostate tissue is also susceptible.

"Our research provides the first direct evidence that exposure to BPA during development, at the levels we see in our day-to-day lives, increases the risk for prostate cancer in human prostate tissue," Prins said

This study was done in rats, but thought to also apply to humans. From Science Daily:

Common BPA substitute, BPS, disrupts heart rhythms in females

Bisphenol S (BPS), a common substitute for bisphenol A (BPA) in consumer products, may have similar toxic effects on the heart as previously reported for BPA, a new study finds.

There is implied safety in BPA-free products. The thing is, the BPA analogs -- and BPS is one of them -- have not been tested for safety in humans." "Our findings call into question the safety of BPA-free products containing BPS," he said. "BPS and other BPA analogs need to be evaluated before further use by humans."

BPA is in many consumer products, but research is finding more and more problems with it. The findings of these two studies may motivate people to try to lower their exposure to plastics and BPA. From Newsweek:

BPA Levels Higher in Men With Prostate Cancer: Study

Bisphenol-A is everywhere. If you are reading this in the United States, there is a greater-than-90 percent chance you have BPA in your system, according to the Centers for Disease Control. The chemical is nearly ubiquitous: it is all over your receipts and soup cans, and it gives plastic bottles useful properties like flexibility and durability. It also mimics human estrogen in the body, and studies have linked it to breast cancer, diabetes, obesity, and hormone abnormalities in children, though what doses are dangerous is a matter of debate.

Now, for the first time, scientists are adding prostate cancer to the list of possible health problems from exposure.

Prostate cancer is the second most prevalent form of cancer among men, afflicting one in six, mostly later in life. A new study published Monday in the journal Plos One found that men with prostate cancer have BPA in their urine at levels 2- to 4-fold higher than cancer-free men. Aging is the best-known risk for prostate cancer, which makes the study’s findings particularly salient: BPA concentrations were especially high in prostate cancer patients under the age of 40, when aging is less of a contributing factor to the development of prostate cancer.

From Science Daily:

BPA linked to breast cancer tumor growth

UT Arlington biochemists say their newly published study brings researchers a step closer to understanding how the commonly used synthetic compound bisphenol-A, or BPA, may promote breast cancer growth.

Subhrangsu Mandal, associate professor of chemistry/biochemistry, and Arunoday Bhan, a PhD student in Mandal's lab, looked at a molecule called RNA HOTAIR. HOTAIR is an abbreviation for long, non-coding RNA, a part of DNA in humans and other vertebrates. HOTAIR does not produce a protein on its own but, when it is being expressed or functioning, it can suppress genes that would normally slow tumor growth or cause cancer cell death.

High levels of HOTAIR expression have been linked to breast tumors, pancreatic and colorectal cancers, sarcoma and others.

UT Arlington researchers found that when breast cancer and mammary gland cells were exposed to BPA in lab tests, the BPA worked together with naturally present molecules, including estrogen, to create abnormal amounts of HOTAIR expression. 

"We were surprised to find that BPA not only increased HOTAIR in tumor cells but also in normal breast tissue," said Bhan. He said further research is needed, but the results beg the question -- are BPA and HOTAIR involved in tumor genesis in addition to tumor growth?

BPA has been widely used in plastics, such as food storage containers, the lining of canned goods and, until recently, baby bottles. It belongs to a class of endocrine disrupting chemicals, or EDCs, which have been shown to mimic natural hormones. These endocrine disruptors interfere with hormone regulation and proper function of human cells, glands and tissue.