Green Tea: Mixed Reviews For Cancer Prevention

Lifestyle choices are pieces of the cancer prevention puzzle, but exactly which steps to take remain unclear, even to scientists. Still, more and more individuals are incorporating small changes into their daily routine — such as drinking green tea — in hopes of keeping cancer risk at bay.

Is it working? A large new Cochrane review of studies that examined the affect of green tea on cancer prevention has yielded conflicting results.

Researchers looked at 51 medium- to high-quality studies that included more than 1.6 million participants. The studies focused on the relationship between green tea consumption and a variety of cancers, including breast, lung, digestive tract, urological prostate, gynecological and oral cancers.

The comprehensive review analyzed studies conducted from 1985 through 2008. Many of the reviewed studies took place in Asia, where tea drinking is widespread and part of the daily routine for many.

The review appears in a recent issue of The Cochrane Library, which is a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.

“Despite the large number of included studies the jury still seems to be out on the question of whether green tea can in fact prevent the development of various cancer types,” said lead review author Katja Boehm, Ph.D. Since people drink varying amounts of green tea, and different types of cancers vary in how they grow, it is impossible to state definitively that green tea is “good” for cancer prevention.

“One thing is certain…green tea consumption can never account for cancer prevention alone,” said Boehm, a member of the Unconventional and Complementary Methods in Oncology Study Group in Nuremburg, Germany.

Three types of tea — black, green and oolong — come from the plant Camellia sinensis, and all contain polyphenols. Catechins, a subgroup of the polyphenols, are powerful antioxidants. Some say the polyphenols in green tea are unique, preventing cell growth and thus having the potential to prevent cancer.

The review found that green tea had limited benefits for liver cancer, but found conflicting evidence for other gastrointestinal cancers, such as cancer of the esophagus, colon or pancreas. One study found a decreased risk of prostate cancer for men who consumed higher quantities of green tea or its extracts.

The review did not find any benefit for preventing death from gastric cancer, and found that green tea might even increase the risk of urinary bladder cancer. Despite conflicting findings, there was “limited moderate to strong evidence” of a benefit for lung, pancreatic and colorectal cancer. None of the studies that simply observed a group of people over time found a benefit for breast cancer prevention. However, both of the case control studies — which compare people without a condition to people with it — found a positive association between green tea consumption and a decreased risk of breast cancer.

Nagi Kumar, Ph.D., director of Nutrition Research at Moffitt Cancer Center in Tampa, Fla., is optimistic about the potential for green tea in cancer prevention. “The substances found in green tea are certainly promising,” Kumar said. “The field now has progressed to where we [can]…test the effectiveness and safety of green tea polyphenols using a drug form similar to the constituents in tea to see if we can prevent cancer progression. Time will tell.”

Kumar said the Cochrane review was “more an inventory of studies completed rather than a systematic scientific review,” adding that “the discussion lacks a scientific approach in the interpretation of the discordant findings.”

Kumar also noted that several groups are conducting randomized clinical trials, including one comprising six institutions: the Moffitt Cancer Center and the James A Haley VA Medical Center, University of Chicago, Jefferson in Philadelphia, University of Florida and Louisiana State University.

Both scientists agreed that more research is a good idea. Boehm said she highly recommends the conduction of a large, well-designed, study with adequate green tea consumption levels.

“The review provides where we have been in this field of research and where we are going and how much more we have on hand,” Kumar said. “Although not as thorough as I would like it, it is a good quality review.”

Therefore, while the questions about green tea consumption and cancer prevention remain unanswered, one thing remains clear: It is fine to consume green tea if you enjoy it and it might prove beneficial in the over time.

“If not exceeding the daily recommended allowance those who enjoy a cup of green tea should continue its consumption,” Boehm said. “Drinking green tea appears to be safe at regular, habitual and moderate use at its recommended dosage of up to 1200 ml/day.” That comes to a little over five cups a day.

No More Federal Marijuana Raids Under President Obama

Raids by the federal government on legally sanctioned medical marijuana facilities will become a thing of the past. President Obama is averse to using federal funds for this purpose, particularly when state law provides for medicinal marijuana use. Moving forward, decisions on medical marijuana raids will be left up to state government. Most states individually have their own laws regarding medical marijuana distribution and supply, but to the federal government it is illegal and under President Bush the federal government had used their laws and power to override the individual state laws regarding medical marijuana.

During a press conference on Wednesday, the new U.S. Attorney General Eric Holder was questioned about drug raids implemented in California on marijuana dispensaries since President Obama took office. Holder said these raids will not be a part of President Barack Obama's policies. According to White House spokesperson Nick Schapiro, in his response to an advocacy groups’ protests to the raids, Obama had not yet appointed his drug policy team when these raids took place. He said, "The president believes that federal resources should not be used to circumvent state laws" and plans to execute this as a policy.

During previous presidencies, policies were passed in an attempt to circumvent medical marijuana use and distribution. During the Clinton administration, there was a Supreme Court case which shut down nonprofit organizations supplying marijuana to its members. Bush’s administration also blocked attempts to grow marijuana for research studies to determine its medical properties.

President Obama’s view seems a little different from his most recent predecessors. He explained during one of his candidacy appearances how his mother had succumbed to cancer and explained that he did not see a difference between doctor-prescribed pain relievers such as morphine and marijuana. While on the campaign trail he also explained that he felt it was “entirely appropriate" for states to legalize medical use of marijuana, "with the same controls as other drugs prescribed by doctors." Bill Piper, national affairs director of the Drug Policy Alliance, a marijuana advocacy group said, "I think it definitely signals that Obama is moving in a new direction, that it means what he said on the campaign trail that marijuana should be treated as a health issue rather than a criminal justice issue."

Some states, such as California have already legalized the use of medical marijuana distribution and use. However, in the past, the DEA had the legal authority to make arrests, even shutting down operations, overriding individual state laws allowing the growth and distribution of medical marijuana. Based on President Obama and the new Attorney General’s recent statements, this will no longer be the policy. The states will be left to implement their laws and policies in regards to medical marijuana. Marijuana advocates are excited and hopeful that this new way of thinking by our top leaders may help to allow for more research and eventually lead to medical marijuana being available at neighborhood pharmacies.

Migraine Sufferers Appear to Have Reduced Risk of Breast Cancer

Almost everyone gets headaches at one time or another, but for millions of Americans who have migraines, they are more than just an occasional annoyance; they are often disruptive and debilitating. The pain is a severe throbbing on one or both sides of the head that can last for hours, or even days, and is often accompanied by nausea, dizziness, and sensitivity to light, sound or smells. But scientists say there is a bright spot for women who suffer these disabling headaches, and it’s not an aura.

A new study, led by Dr. Christopher I. Li of Fred Hutchinson Cancer Research Center in Seattle, comparing data on more than 9,000 women revealed that women with a history of migraines have a 26 percent reduced risk of breast cancer. This held true regardless of the woman’s menopausal status, age when she was first diagnosed with migraines, whether she used prescription medications for her headaches, or what triggers she might have been avoiding. These findings confirm a previous study reported last November, also by Li and his team, which found a 33 percent lower breast cancer risk among women with migraines. “This research suggests that women with migraine may have a lower risk of breast cancer,” said Li, adding that it could lead to a new way of understanding how breast cancer works. “If we can better understand what the biological mechanisms are, that could open new avenues for research into breast cancer prevention.”

While the researchers aren’t sure exactly why women who get migraines appear to have a reduced breast cancer risk, they suspect that hormones, estrogen in particular, are a likely explanation. “It’s pretty clear that migraine, like breast cancer, is a hormonally related disease,” Li said. “Many triggers for migraine are also things that reduce estrogen levels.” On the other hand, increased levels of estrogen are known to boost the risk for breast cancer, therefore it’s “biologically plausible” that migraine sufferers would be less prone to breast cancer.

The researchers say increased use of non-steroidal anti-inflammatory drugs (NSAIDS), such aspirin, ibuprofen and naproxen, by migraine sufferers could also explain some, but probably not all, of the reduction in breast cancer risk. A recent analysis of several studies showed a link between NSAID use and a 12 percent lower breast cancer risk. “Further work is needed to resolve what accounts for this relationship,” the researchers concluded.

Li added that women with migraines should “still have the same breast cancer screenings and follow-up,” and recommendation echoed by Dr. Michael Kraut, director of oncology at Providence Hospital in Southfield, Michigan. “The reduction in breast cancer risk in this study was about one-quarter, but it doesn’t eliminate the risk, so women still need to be on the lookout.”

Kraut also agrees that the link between migraines and breast cancer risk is likely a hormonal one. “The theory they propose here is that women who have migraines may have drops in estrogen levels that trigger migraines. And women who have sustained, increased levels of estrogen have a higher risk of breast cancer,” he said “This looks like one more piece of evidence that prolonged high levels of estrogen are dangerous.”

Li and team are now onto the next step—they are contacting women from the previous studies in hopes of learning more about the effects of different kinds of migraines. “We’re trying to understand what are the types of migraine that are most related to reduction in breast cancer risk,” Li says.

The study appears in the July issue of Cancer Epidemiology, Biomarkers and Prevention, a journal of the American Association for Cancer Research.

H1N1 Flu Vaccinations Could Begin in October

Since the H1N1 flu emerged in March in Mexico and Southern California, the virus has infected an estimated 1 million Americans, killing 170, and is still spreading, despite the summer’s heat and humidity, which influenza usually cannot tolerate. This persistence makes the virus’ resurgence in the fall all but certain and leaves little time to prepare. “We have a little bit more than a month ... to get our acts together,” Dr. Anne Schuchat of the U.S. Centers for Disease Control and Prevention said during a summit at the National Institutes of Health in Bethesda, Maryland on Thursday, where officials announced their game plan to deal with the threat, including the vaccination schedule and the target populations. About 500 state and local health officials were in attendance, as was President Barack Obama, who took time from his G-8 summit in Italy to join by teleconference.

Health and Human Services Secretary Kathleen Sebelius said if all goes well, H1N1 vaccinations could begin by mid-October, and while officials have not yet decided exactly which age groups will be recommended to get the vaccine, school-age children, young adults with risky conditions such as asthma, pregnant women, and health workers are likely to be among the first in line. But the timetable is largely dependent on the outcome of studies with experimental vaccine batches that are set to begin the first week of August. Sebelius said that as soon as the vaccines were approved and available, the federal government would purchase them from the manufacturers and share them free among the states, which must then “try and get this in the arms of the targeted population as soon as possible.”

Sebelius acknowledged that this fall is likely to be a confusing season, with doctors’ offices, clinics, grocery stores and drug stores dispensing doses of regular seasonal flu vaccine as well as the H1N1 vaccine, which will probably have to be given in two separate inoculations. Schools and day care centers may also be utilized to mount a mass vaccination program against the H1N1 virus. “Since the population that seems to be most affected is younger folks, school-aged kids, kids in day care centers, we may well partner with the schools, looking at those as possible sites for a vaccination program,” said Sebelius.

Sebelius urged the summit attendees to go home and get schools, mayors and other community leaders to spread that message. “The last thing we want is millions of parents to be surprised” when the get-your-child-vaccinated-at-school note comes home. She also warned against complacency. “What we can’t do is wait until October and then suddenly decide that we have a very serious situation on our hands,” she said.

Sebelius said the federal government will provide $350 million by the end of July to help states develop specific plans for combating the pandemic and to help hospitals brace for a surge of demand. “We want to make sure we are not promoting panic but we are promoting vigilance and preparation,” Obama told the gathering. “We may end up averting a crisis. That’s our hope.”

Many other issues have yet to be hammered out, such as guidelines for closing schools where infected students are found, and how to keep students learning if schools are closed for extended periods. And an even bigger problem: When schools close and working parents must stay home, or when workers get sick and don’t get paid for time off. Usually, they go to work despite their illness, spreading infection to co-workers. “How are we going to assist people who don’t have benefits?” asked Paul Jarris of the Association of State and Territorial Health Officials.

Homeland Security Secretary Janet Napolitano said she is currently working with the Labor Department to address that question, and she urged employers to make other provisions, such as telecommuting, should H1N1invade their workplaces this fall.

“Trojan Horse” Used to Terminate Cancer Cells

Scientists have long been looking for a better way to fight the battle of cancer, rather than the traditional radiation and chemotherapy treatments, both of which damage healthy cells instead of just the cancerous ones. Now, they might have found the answer with a new treatment they call the “Trojan horse” therapy.

A team of researchers in Australia have developed the new “Trojan horse” therapy to help combat cancer by using a bacterially-derived nano cell to help penetrate and disarm the cell that is cancerous before a second nano cell kills it with the chemotherapy drugs. The “Trojan horse” therapy has the potential to target the cancer cells directly with chemotherapy, rather than the current treatment where drugs are injected into the cancer patient and end up attacking both the healthy and the cancer cells.

The scientists in Sydney, Dr. Jennifer MacDiarmid and Dr. Himanshu Barhmbhatt who formed EnGenelC Pty Ltd in 2001, stated that they have achieved a 100 percent rate of survival in mice with human cancer cells by using the “Trojan horse” therapy over the past two years. They plan to start the clinical trials on humans within the coming months. However, the human trials of the cell delivery system will begin next week at The Austin located at the University of Melbourne and the Peter MacCullum Cancer Center at the Royal Melbourne Hospital.

The therapy, which was published in the latest Nature Biotechnology journal, sees the mini-cells that are called EDVs (EnGenelc Delivery Vehicle) attach and then enter the cancer cell. The first wave of these mini-cells release ribonucleic acid molecules, which are called siRNA, that are used to switch off the production of proteins that make the cancer cell resistant to the chemotherapy treatment. Then, a second wave of the EDV cells are accepted by the cancer cells and release the chemotherapy drugs, in turn, killing the cancer cell.

MacDiarmid stated, “The beauty is that our EDVs operate like ‘Trojan horses’. They arrive at the gates of the affected cells and are always allowed in. We are playing the rogue cells at their own game. They switch-on the gene to produce the protein to resist drugs, an we are switching-off the gene which, in turn, enables the drugs to enter.”

RNA interference, also known as RNAi, is designed to help silence the genes that are responsible for producing disease-causing proteins and is considered one of the hottest areas of biotechnology research. The subject of RNA was the basis of the 2006 Nobel Prize in medicine. Dozen of biotechnology companies are already looking for way that they can manipulate RNA to help block the genes that produce disease-causing proteins that are involved in blindness, cancer or AIDS.

Brahmbhatt said that after the treatment with the conventional drug therapy, a high number of the cancer cells are terminated, however, a small percentage of the cells can produce the proteins that make cancer cells resistant to the chemotherapeutic medications. “Consequently, follow-up drug treatments can fail. The tumors thus become untreatable and continue to flourish, ultimately killing the patient. We want to be part of moving toward a time when cancers can be managed as a chronic disease rather than being regarded as a death sentence,” he stated.

The Nature report said that the mini-cells were well tolerated by the animals that were actively treated with no adverse side effects or deaths, despite the repeated dosing. MacDiarmid said, “Significantly, our methodology does not damage the normal cells and is applicable to a wide spectrum of solid cancer types. The hope is that the benign nature of this EDV technology should enable cancer sufferers to get on with their lives and operate normally using outpatient therapy.”

Study Links ADHD Drugs To Sudden Death In Children

A new study by researchers in the US suggests there may be a link between the use of stimulant drugs for attention-deficit hyperactivity disorder (ADHD) and sudden cardiac death in healthy children, but the US Food and Drug Administration (FDA), who funded the study with the National Institute of Mental Health, said because of its limitations, parents and carers should not stop giving children such medication on the basis of this study but should discuss any concerns with their prescribing doctor.

The study was the work of lead author Dr Madelyn S Gould of Columbia University, New York, New York, and colleagues, and is published in the 15 June issue of the American Journal of Psychiatry.

In the case-control study, using state-based mortality data from 1985 to 1996, Gould and colleagues compared the use of stimulant drugs in 564 healthy children aged 7 to 19 from across the US who died suddenly and most likely due to sudden cardiac disturbance with a matched group of 564 young people who died as passengers in motor vehicle traffic accidents.

The primary measure of exposure was the presence of stimulant medication as noted in the medical examiner records, toxicology reports and death certificates. The stimulants involved were amphetamine, dextroamphetamine, methamphetamine, and methylphenidate.

The results showed that out of the 564 healthy children who died suddenly, 10 (1.8 per cent) were taking stimulants, specifically methylphenidate (better known in the US under its brand name of Ritalin). This compared with only 2 children (0.4 per cent) in motor vehicle accident comparison group, only one of whom was taking Ritalin (methylphenidate).

Logistical regression, a tool commonly used by epidemiologists, showed a statistically significant link between stimulant use and sudden unexplained death in a primary analysis. This result was supported qualitatively in a further "comprehensive series of sensitivity analyses", wrote the authors, who concluded that:

"This case-control study provides support for an association between the use of stimulants and sudden unexplained death among children and adolescents."

"Although sudden unexplained death is a rare event, this finding should be considered in the context of other data about the risk and benefit of stimulants in medical treatment," they added.

In a Safety Communication released on 15 June, the FDA said that:

"The FDA can not conclude that the data in the study affect the overall risk-benefit profile of stimulant medications used to treat ADHD in children."

What they are saying is they are not going to change their advice about the risks versus the benefits of the medication because of the study's limitations, which they say include:

* The significant time lag between when the deaths occurred and when the data was collected.

* The different circumstances around each death that may have affected how well family members and/or carers may have remembered details of any medication the deceased child had been using.

* Sudden unexplained death in a child would be more likely to initiate a post-mortem inquiry than a death due to blunt force trauma in a motor vehicle accident.

* The low frequency of stimulant medication use by the children in both the study and the control groups.

When scientists highlight a study's limitations they are in effect saying that another study looking at the same things might reach a different result if it didn't have those limitations.

With subjects as serious as this, and with parents and carers rightly concerned about what to do about any ADHD medication their children have been prescribed, it is important that research in the service of public health produces results that are robust and reliable, so a small study like this one really needs to be confirmed by more research, preferably with a larger study, especially if there are concerns about its limitations.

In fact, the FDA is already co-sponsoring another larger study that is looking at the link between increased risk of heart attack, stroke and other cardiovascular problems and use of stimulant medication by children, the results of which are expected to come out later this year.

Dr Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research told the press:

"The FDA continues to review drug safety information for stimulant medications used to treat ADHD so that we can give health care professionals and families the most up-to-date drug safety information available."

The federal agency urged doctors to follow the current prescribing information that accompanies the product label, which recommends that young and adult patients being considered for ADHD treatment:

"Work with their health care professional to develop a treatment plan that includes a careful health history for cardiovascular disease in the child and his or her family."

Such preparation should include a physical exam that pays particular attention to the cardiovascular system, and should consider screening tests such as electrocardiogram and echocardiogram, depending on the patient's history and whether it suggests possible risk factors for heart disease.

"Sudden Death and Use of Stimulant Medications in Youths."
Gould, Madelyn S., Walsh, B. Timothy, Munfakh, Jimmie Lou, Kleinman, Marjorie, Duan, Naihua, Olfson, Mark, Greenhill, Laurence, Cooper, Thomas.
Am J Psychiatry, Published online 15 June 2009.
doi: 10.1176/appi.ajp.2009.09040472

Chemotherapy Drug May Improve Appearance Of Sun Damaged Skin, Study

Researchers in the US found that the chemotherapy drug fluorouracil appeared to reduce the appearance of sun-damaged and aging skin as well as the number of potentially pre-cancerous skin patches.

The study was the work of Dr Dana L Sachs, associate professor in the Department of Dermatology at the University of Michigan, Ann Arbor, and colleagues, and is published in the 6 June issue of Archives of Dermatology, one of the Journal of the American Medical Association/Archives journals.

Fluorouracil, which is used in chemotherapy treatment of cancers of the colon, head and neck, pancreas and other organs, stops the body being able to make thymine, a building block of DNA. Researchers studying cancer patients having treatments with fluorouracil have noticed changes in skin appearance and as a result of this the drug was developed as a skin cream to treat potentially pre-cancerous skin patches.

For this study, Sachs and colleagues asked 21 healthy volunteers with sun-damaged skin and lesions to apply 5 per cent fluorouracil cream to the face twice a day for two weeks and regularly examined their skin for molecular and clinical changes during this time and also for another 22 weeks afterwards.

This included taking biopsies, taking photographs and doing clinical evaluations at the start and then at intervals during the treatment period.

19 of the volunteers completed all parts of the study and 20 filled in questionnaires at week 10.

Three dermatologists who were not part of the research team who examined the volunteers during the study were invited to evaluate the photographs which were taken at the end of week 1, 2, 4, 6, 10 and 24 of the study.

The results showed that:

* The number of lesions at the end of treatment was significantly lower than the number at the start of treatment.

* This went down from an average of 11.6 lesions per volunteer to an average of 1.5.

* The clinical evaluation identified overall improvements in aging-related damage.

* This included reductions in wrinkling, dark skin spots, skin that has become darker (hyperpigmentation) and sallowness (when the skin tone goes yellow).

* Skin biopsies taken just after the end of treatment showed an increase in the compounds that are produced when skin is injured and inflamed and when the non-living tissue that acts like a "scaffold" for living skin cells, the extracellular matrix, breaks down.

* After this stage, levels of a collagen precursor called procollagen, appeared to increase (collagen is the main protein in skin and tends to lessen when skin is photo-damaged, also it fragments and degrades as skin ages).

* The treatment was well tolerated and according to the questionnaire they filled in during week 10, 95 per cent of the volunteers rated their skin as improved while 89 per cent said they would be willing to have the treatment again.

The authors concluded that:

"Topical fluorouracil causes epidermal injury, which stimulates wound healing and dermal remodeling resulting in improved appearance. The mechanism of topical fluorouracil in photoaged skin follows a predictable wound healing pattern of events reminiscent of that seen with laser treatment of photoaging."

They noted that patients who receive fluorouracil treatment for skin lesions are likely also to benefit from a reduction in sun-damage, a side-effect that may motivate them to persevere with the "rigorous" treatment. It is also possible that for some patients the drug could have an important role against photo-aging, they commented.

But some patients may not be prepared to endure two or three weeks with the cream on their face or other part of their skin, and then the rather unsightly after effects for several more weeks, while others may be prepared to do it if the cost proves to be much lower than ablative laser resurfacing. For the typical patient the skin gets dry, it itches and peels for several weeks before it recovers and gets softer.

The study was sponsored by Valeant Pharmaceuticals International who make Efudex, the cream that was used.

"Topical Fluorouracil for Actinic Keratoses and Photoaging: A Clinical and Molecular Analysis."
Dana L. Sachs; Sewon Kang; Craig Hammerberg; Yolanda Helfrich; Darius Karimipour; Jeffrey Orringer; Timothy Johnson; Ted A. Hamilton; Gary Fisher; John J. Voorhees.