Japanese scientist urges withdrawal of own 'breakthrough' stem cell research

TOKYO/LONDON -- A Japanese scientist has called for his own headline-grabbing study on stem cells to be withdrawn from publication, saying its findings had now been thrown into too much doubt.

The research -- hailed when it came out in January as a breakthrough that could herald a new era of medical biology -- was covered widely in Japan and across the world after it was published in the highly reputable science journal Nature.

But since then, there have been reports that other scientists have been unable to replicate the Japanese team's results and that there may have been problems with its data and images.

"It is no longer clear what is right," Teruhiko Wakayama, a professor at Japan's University of Yamanashi who was part of the researcher team, told public broadcaster NHK.

The study, described as game changing by independent experts asked to comment on it when it was published, appeared to show a simple way to reprogram mature animal cells back into an embryonic-like state that would allow them to generate many types of tissue.

The results appeared to offer a promise that human cells might in future be simply and cheaply reprogrammed back into embryonic cell-like cells -- in this case cells dubbed Stimulus-Triggered Acquisition of Pluripotency, or STAP, cells -- suggesting a simple way to replace damaged cells or grow new organs for sick and injured people.

"When conducting the experiment, I believed it was absolutely right," Wakayama said.

"But now that many mistakes have emerged, I think it is best to withdraw the research paper once and, using correct data and correct pictures, to prove once again the paper is right. If it turns out to be wrong, we would need to make it clear why a thing like this happened."

A Nature spokesperson said "issues relating to this paper" had been brought to the journal's attention and it was conducting an investigation, but made no further comment.

‘Open mind’

Robin Lovell-Badge, a stem cell expert at Britain's National Institute for Medical Research, cautioned against premature assumptions on whether the research was flawed.

"I have an open mind on this," he told Reuters. "I'm waiting to hear from several serious stem cell labs around the world on whether they have been able to reproduce the methods."

Wakayama's co-researcher Haruko Obokata, became an instant celebrity in Japan after she spoke during a Nature media briefing to science reporters all over the world about her eye-catching findings.

The Japanese researchers, joined by others from Brigham and Women's Hospital and Harvard Medical School in the United States, took skin and blood cells, let them multiply, then subjected them to stress "almost to the point of death", they explained, by exposing them to various events including trauma, low oxygen levels and acidic environments.

One of these "stressful" situations was simply to bathe the cells in a weak acid solution for around 30 minutes. Within days, the scientists said they had found that the cells had not only survived but had also recovered by naturally reverting into a state similar to that of an embryonic stem cell.

Yet no other research team has yet been able to replicate the findings, and the RIKEN Center for Developmental Biology in Japan, where Obokata works, said last week it had "launched an independent inquiry into the content of the paper.

That inquiry would be conducted by a panel of experts from within and outside RIKEN, it said, and would be published as soon as it was concluded.

A RIKEN spokesman declined to comment on Wakayama's call for the paper to be withdrawn.

source: interaksyon.com

Human trials begin for anti-skin cancer vaccine

WASHINGTON - An experimental vaccine implant to treat skin cancer has begun early trials in humans, as part of a growing effort to train the immune system to fight tumors, researchers said Friday.

The approach, which was shown to work in lab mice in 2009, involves placing a fingernail-sized sponge under the skin where it reprograms a patient's immune cells to find cancerous melanoma cells and kill them.

"It is rare to get a new technology tested in the laboratory and moved into human clinical trials so quickly," said Glenn Dranoff, professor of medicine at Harvard Medical School and part of the research team at the Wyss Institute for Biologically Inspired Engineering at Harvard University.

The phase I trial aims to test the safety of the implant in a small number of human patients. After that, the device may move to phase II trials on effectiveness and larger phase III trials before reaching the market.

The implants are made of biodegradable polymer material that are highly permeable and contain antigens that are specific to the kind of tumor being targeted.

The device releases a protein that attracts immune cells and sends them out armed to hunt down and kill tumor cells.

Researchers say it works differently than conventional cancer vaccines -- which involve removing immune cells from the patient, reprogramming them to attack malignancies and reinjecting them -- because it works from inside the body.

One drug already on the market using the immune system against melanoma, called Yervoy, is made by Bristol Myers Squibb and was approved by US regulators in 2011.

Pharmaceutical giants Merck and Roche also have drugs that use the immune system to fight cancer in clinical trials.

British pharma giant GlaxoSmithKline suffered a blow this week when its phase III trial of vaccine candidate MAGE-A3 did not extend survival in melanoma patients who received the vaccine after their tumors were surgically removed.

source: interaksyon.com

Studies find an aspirin a day can keep cancer at bay

LONDON (Reuters) - Three new studies published on Wednesday added to growing scientific evidence suggesting that taking a daily dose of aspirin can help prevent, and possibly treat, cancer.

Previous studies have found that daily aspirin reduces the long-term risk of death due to cancer, but until now the shorter-term effects have been less certain - as has the medicine's potential in patients already diagnosed with cancer.

The new studies, led by Peter Rothwell of Britain's Oxford University, found that aspirin also has a short-term benefit in preventing cancer, and that it reduces the likelihood that cancers will spread to other organs by about 40 to 50 percent.

"These findings add to the case for use of aspirin to prevent cancer, particularly if people are at increased risk," Rothwell said.

"Perhaps more importantly, they also raise the distinct possibility that aspirin will be effective as an additional treatment for cancer - to prevent distant spread of the disease."

This was particularly important because it is the process of spread of cancer, or "metastasis", which most often kills people with the disease, he added.

Aspirin, originally developed by Bayer, is a cheap over-the-counter drug generally used to combat pain or reduce fever.

The drug reduces the risk of clots forming in blood vessels and can therefore protect against heart attacks and strokes, so it is often prescribed for people who already suffer with heart disease and have already had one or several attacks.

Aspirin also increases the risk of bleeding in the stomach to around one patient in every thousand per year, a factor which has fuelled an intense debate about whether doctors should advise patients to take it as regularly as every day.

Last year, a study by British researchers questioned the wisdom of daily aspirin for reducing the risk of early death from a heart attack or stroke because they said the increased risk of internal bleeding outweighed the potential benefit.

Other studies, including some by Rothwell in 2007, 2010 and 2011, found that an aspirin a day, even at a low dose of around 75 milligrams, reduces the long-term risk of developing some cancers, particularly bowel and oesophageal cancer, but the effects don't show until eight to 10 years after the start of treatment.

Rothwell, whose new studies were published in The Lancet and The Lancet Oncology journals on Wednesday, said this delay was because aspirin was preventing the very early development of cancers and there was a long time lag between this stage and a patient having clinical signs or symptoms of cancer.

Rothwell and others said deeper research was now needed into aspirin as a potential treatment for cancer in patients whose disease has not yet spread.

"No drug has been shown before to prevent distant metastasis and so these findings should focus future research on this crucial aspect of treatment," he said.

Peter Johnson, chief clinician at the charity Cancer Research UK, said his group was already investigating the anti-cancer properties of aspirin. "These findings show we're on the right track," he said.

In a written commentary on the research in The Lancet, Andrew Chan and Nancy Cook of Harvard Medical School in the United States said it was "impressive" and moved health experts "another step closer to broadening recommendations for aspirin use".

source: mb.com.ph