Scientists’ discovery that cancerous cells grow like fetal cells could lead to better, safer medications

Tumour study offers drug hope

Scientists’ discovery that cancerous cells grow like fetal cells could lead to better, safer medications

Mar 13, 2008 04:30 AM


Health Reporter
Harvard University scientists have discovered a fundamental mechanism of tumour growth, a breakthrough that may lead to more effective and less toxic treatments for cancer.

Indeed, two studies, published today in the journal Nature, may lead researchers to a potential “magic bullet” drug, that could attack many different forms of the disease, a top Canadian cancer expert says. 

“This (research will present) one of the cancer (drug) targets that potentially could hit a whole variety of cancers. And there aren’t very many (drugs) like that,” says Philip Branton, head of cancer research with the Canadian Institutes of Health Research.

The twin Harvard studies show that cancer cells switch on the same sugar metabolizing enzymes as those found in fetal cells, explaining for the first time why tumours are able to grow so rapidly.

Like fetal cells, whose main job is to grow and divide to make a baby in just nine months, tumour cells grow and proliferate much more rapidly than normal adult tissues.

And to do so, both cancer and embryonic cells need to utilize energy, derived from sugary fuels, differently than their normal adult counterparts, Harvard biologist Lewis Cantley, the senior study author on both papers, said.

It’s been known for almost eight decades that tumour cells metabolize – or create energy from nutrients – at a much different rate than normal cells. This is the Warburg effect. What was unclear, says Cantley, was how they did this and whether or not the altered metabolic process was essential to tumour growth.

In the studies, scientists at the Harvard Medical School and Boston’s Beth Israel Deaconess Medical Centre showed that an enzyme that breaks down sugars in adult cells was switched to its embryonic version in cancer cells. Known as pyruvate kinase, the enzyme has an adult version, called M1 and a fetal version, M2.

“What our papers show is the embryonic form (M2) is designed to use glucose to make cells grow … the glucose gets incorporated into making DNA, RNA, proteins, lipids. It’s made into the cell building blocks,” Cantley says. “An adult cell is no longer growing so it uses glucose for energy.”

Branton says the study represents a significant breakthrough in cancer research. “It’s a major advance in understanding one of the oldest enigmas of cancer, which is the Warburg effect,” he says.

Critically, the Nature studies show that without the M2 version of the enzyme, tumour growth is slowed or outright halted. To show this the researchers genetically knocked out the ability to create M2 in several forms of human cancer cells, transplanting an M1 production component instead.

“We demonstrated that if you replaced the M2 the tumour cell has with the adult M1 form and implant that into a mouse, if fails to grow,” Cantley says.

He says the importance of M2 enzyme in tumour growth will make it an intriguing new target for better, safer cancer drugs.

Because normal adult tissues use the M1 version, a drug that specifically targeted M2 would, presumably, have minimal effect on anything outside of the tumour itself, Cantley says.

“That’s why we’re very excited about this as major tissues like the heart, the brain, the liver, those tissues don’t use the M2 form at all,” he says.

“If you had a (drug) that hit M2 … that should have no effect on the heart or the brain or the liver, which are the tissues you most worry about with cancer drugs. It should be far less toxic than … current chemotherapy.”

Branton, however, cautions that a drug that would specifically

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Cancer-Causing Benzene Still in Drinks

Nearly one out of ten of 200 beverage samples analyzed in a recent study by the EPA and FDA still had benzene levels above the U.S. EPA drinking water limit of 5 parts per billion (ppb).Many manufacturers have reformulated their products to minimize or eliminate benzene. In these reformulated products, benzene levels were 1.1 ppb or less. About 71 percent of beverage samples contained less than 1 ppb.

Benzene can form in beverages that contain the preservative benzoate salt and ascorbic acid (vitamin C). Beverages were reformulated in the early 1990’s to avoid benzene formation, but it has recurred in recent years because new manufacturers were unaware of the problem and added vitamin C to drinks.

doctors failed to report an incompetent colleague

2007

A survey of 1,600 practicing physicians published in the Annals of Internal Medicine reveals that reveals that nearly half of all doctors failed to report an incompetent colleague who posed a risk to the health or safety of a patient. The same survey also revealed that a majority of doctors would send their patients to get expensive imaging work done at an imaging facility in which they held a financial interest, but only 24 percent of doctors said they would reveal that conflict of interest to patients.

Result: Yet more incompetent, dishonest doctors continue to scam customers and harm patients. The scourge of modern medicine continues as corrupt, ignorant and downright incompetent doctors continue to harm millions of expectant mothers, infants, babies and children with their deadly Big Pharma chemicals and disastrous health advice. The reputation of doctors plummets in the minds of the American public, and most patients now turn to the Internet to find answers that their doctors either don’t know or refuse to tell them. The mass exodus of patients away from conventional medicine is now well underway…

High-Dose Chemo Doesn’t Help Breast Cancer

Getting diagnosed with cancer is difficult enough, but choosing the right treatment from the bewildering array of options can be just as challenging. For breast cancer patients, that decision just got a little less complicated, with a new study showing that a once-popular therapy doesn’t provide any additional survival benefit.

Researchers at M.D. Anderson Cancer Center in Houston announced at the San Antonio Breast Cancer Symposium today that high-dose chemotherapy (followed by a stem-cell transplant to rebuild the immune system) after surgery does not extend the life of breast-cancer patients. The new findings, which come after a thorough analysis of 15 trials involving 6,200 patients, should close the book on a controversial treatment that was popular during the 1980s and 1990s. At the time, doctors believed that more was better when it came to chemotherapy following cancer surgery: While it was painful for patients, oncologists thought ramping up chemo would ultimately benefit patients by destroying any cancer cells that had eluded the surgeon’s knife.

Not everyone agreed with that theory, but advocates for breast-cancer patients, desperate for more and better options, pushed for access to the therapy, resulting in wrangling with some health insurers who refused to cover the treatment, saying it was too experimental. With more sophisticated cancer drugs becoming available in recent years, the demand for high-dose chemotherapy has died down, but, until now, many patients and doctors have still had questions about the usefulness of the treatment.

The multistep therapy requires doctors to extract bone-marrow stem cells from breast-cancer patients prior to surgery. After the tumor-removal operation, patients are exposed to brutal doses of chemotherapy, then re-infused with their stem cells, which restore immune cells destroyed by the chemotherapy. But ultrahigh doses of chemo are extremely toxic, and in fact, some of the 20,000 women who have received the treatment in the U.S. have died from the toxicity.

The M.D. Anderson study, led by Donald Berry, chair of biostatistics, included women with all types of breast cancer, all at the beginning stages of the disease. All had tested positive for cancer in some lymph nodes even after surgery, but none had been diagnosed with cancer that had spread any further. While women receiving the treatment enjoyed a few extra cancer-free months before relapse, they did not survive any longer than women who never underwent the rigorous therapy. “I was surprised by the results,” says Berry. “I was expecting some subsets of women to show some survival benefit. Many studies had been suggesting that there were some patients, such as young patients and women with triple negative cancer” — that is, cancer cells that lack receptors for estrogen, progesterone or HER2, which makes them difficult to treat with drugs — “that would benefit. But our analysis shows that’s not true.”

“This report should absolutely, definitively and for all time close the door on this treatment,” says Dr. Larry Norton of Memorial Sloan-Kettering Cancer Center in New York City.

Despite its negative results, Berry and Norton say the study holds a valuable lesson: that perhaps more important than the size of the dose is which chemo drug the doctor decides to use. Certain cancer cells will either respond to a drug or not — so boosting the dose, particularly of the wrong drug, is not likely to make any difference in these cases. Timing may also be key — spacing apart chemotherapy doses can increase the likelihood of catching tumor cells at their weakest. Taken together, lessons like these are making a difference where it counts most — in giving breast cancer patients the best chance at surviving their disease.

Cannabis compound stops spread of breast cancer: researchers

A compound of the marijuana plant may prevent aggressive breast cancers from spreading throughout the body, new research from the United States suggests.

A team of researchers at the California Pacific Medical Center Research Institute say cannabis compound CBD could provide a non-toxic alternative to chemotherapy for cancer treatments. Previous research has shown the compound can block human brain cancers, and recent lab experiments have shown it may be able to do the same for breast cancer.

“Right now we have a limited range of options in treating aggressive forms of cancer. Those treatments, such as chemotherapy, can be effective but they can also be extremely toxic and difficult for patients,” said researcher Dr. Sean McAllister in a release. “This compound offers the hope of a non-toxic therapy that could achieve the same results without any of the painful side effects.”

CBD works by blocking the activity of gene Id-1, which is associated with metastasis — the spread of cancer cells away from the original tumor site. The compound does not share marijuana’s psychoactive properties.

“We know that Id-1 is a key regulator of the spread of breast cancer,” said senior author Dr. Pierre-Yves Desprez in a release. “We also know that Id-1 has also been found at higher levels in other forms of cancer. So what is exciting about this study is that if CBD can inhibit Id-1 in breast cancer cells, then it may also prove effective at stopping the spread of cancer cells in other forms of the disease, such as colon and brain or prostate cancer.”

Researchers stressed that they were not encouraging cancer patients to smoke pot, adding that it would be highly unlikely for patients to receive an effective concentration of the compound in that way.

The team’s findings were published in the journal Molecular Cancer Therapeutics.

Most Treatments Don’t Fix Back Pain

Nove 8, 2007 

According to Australian researchers, symple therapy and medication is the best form of treatment for a person’s back pain.

In a study featuring 240 participants, all of whom with acute back pain, it was found that anti-inflammatory drugs and spinal manipulation had no increased effect on their recovery time.

Over the duration of the study, participants were divided into groups, which each group receiving a differing form of treatment to take away their back pain. At the conclusion of the study, almost all of the participants were cured of their back pain no matter what form of treatment they received.

“GPs can manage patients confidently without exposing them to increased risks and costs associated with NSAIDs or spinal manipulative therapy,” said Study leader Mark Hancock.

According to Dr Bart Koes from the Department of General Practice at Erasmus University in the Netherlands, “It is very likely that for many patients with acute low back pain currently treated with NSAIDs and/or spinal manipulation this would not have been needed if adequate first-line treatment with paracetamol and advice and reassurance was given.”

Prostate Cancer Therapy May Increase Risk Of Death From Heart Disease

ScienceDaily (Feb. 25, 2007) — Androgen deprivation therapy – one of the most common treatments for prostate cancer – may increase the risk of death from heart disease in patients over age 65, according to a new study by researchers at Dana-Farber Cancer Institute, Brigham and Women’s Hospital and other institutions.

The study results were based on data from CaPSURE, a national registry of men with prostate cancer. Although the findings need to be confirmed in clinical trials, the study authors state that oncologists should weigh the benefits of androgen deprivation therapy, or ADT, against the risk of heart problems in older prostate cancer patients.  Read More ….