By Maggie Fox, Health and Science Editor
WASHINGTON (Reuters) - Human egg cells can be tweaked to give rise to valued stem cells that match the tissue types of many different groups of people, U.S. and Russian researchers reported on Wednesday.
They said the stem cells they have created from unfertilized human eggs look and act like embryonic stem cells.
And they have been carefully tissue-matched in the same way as bone marrow donations to prevent the risk of rejection if they are transplanted into people.
The team at California-based International Stem Cell Corp. hopes to create a bank of tissue-matched stem cells that could be used as transplants that a patient's immune system would accept.
"The process is efficient, it is relatively safe and it is ethically sound," Jeffrey Janus, president and director of research at the company, said in a telephone interview.
The cells are created by a process known as parthenogenesis, a word that comes from Latin and Greek roots meaning virgin beginning.
It involves chemically tricking an egg into developing without being fertilized by sperm.
Several teams have now created parthenogenetic human stem cells from eggs. Other teams have created similar cells using human skin cells or human embryos.
Continune at Reuters
Japanese researchers have used fat-derived stem cells to reconstruct breasts marred by cancer surgery.
The findings, presented at the San Antonio Breast Cancer Symposium, have not yet been peer-reviewed and should be considered preliminary. However, if the procedure proves safe and effective, it could help breast cancer victims and perhaps replace unreliable implants for women seeking cosmetic enhancement.
Kyushu Central Hospital doctor Keizo Sugimachi used liposuction to take fat from the thighs, lower back and hips of 19 breast cancer survivors from whom doctors had removed tumors and parts of their breasts. Some of the fat was processed with a system developed by Cytori Therapeutics, a San Diego-based regenerative medicine company who sponsored Sugimachi's study.
Cytori's processing system pulled stem cells capable of becoming new breast tissue from the fat; these were combined with the rest of the fat, then injected into the womens' breasts. The treated tissues soon swelled from an average thickness of 6 millimeters to 16 millimeters, shrinking by a couple millimeters over the next six months but remaining thicker than before the procedure.
Current breast enhancement procedures rely purely on fat grafts, which are prone to instability, scarring and collapse, or on implants filled with saline or silicone, which can break or cause disfigurement. Apart from a temporary hardening of the injection site, no side effects were reported in Sugimachi's study. Fifteen of the 19 women were reportedly satisfied with the results.
Cytori will conduct two clinical trials of the procedure in Europe in 2008. As mentioned before, it's too early to get excited, but it's worth mentioning that the latest results expand on earlier promise covered by Wired's now-defunct Bodyhack blog.
The study's location in Japan, birthplace of some of the strangest bodily conceptions (NSFW) yet produced by modern imaginations, also makes me wonder what a world of stem cell-based cosmetic procedures might look like. It's a somewhat disturbing thought, but to each his -- or her -- own.
Articel From:http://blog.wired.com/wiredscience/2007/12/better-breasts.html
Images From:Naturalbuy.com
By MARILYNN MARCHIONE
SAN ANTONIO (AP) — For the first time, doctors have used stem cells from liposuctioned fat to fix breast defects in women who have had cancerous lumps removed.
The approach is still experimental, but holds promise for millions of women left with cratered areas and breasts that look very different from each other after cancer surgery. It also might be a way to augment healthy breasts without using artificial implants.
So far, it has only been tested on about two dozen women in a study in Japan. But doctors in the United States say it has great potential.
"This is a pretty exciting topic right now in plastic surgery," said Dr. Karol Gutowski of the University of Wisconsin-Madison. "There are people all over the country working on this."
The Japanese study was reported Saturday at the San Antonio Breast Cancer Symposium. The company that developed the treatment, San Diego-based Cytori Therapeutics, plans larger studies in Europe and Japan next year.
More than 100,000 women have lumps removed each year in the United States. These operations, lumpectomies, often are done instead of mastectomies, which take the whole breast. But they often leave deformities because as much as a third of a woman's breast may be removed.
"It's almost a euphemism" to call it a lumpectomy, said Dr. Sydney Coleman, a plastic surgeon at New York University who has consulted for Cytori and is interested in the stem cell approach.
The defect "initially may not be as noticeable" but it often gets worse, especially if the woman also has radiation treatment, said Dr. Sameer Patel, a reconstructive surgeon at Fox Chase Cancer Center in Philadelphia.
"There's a growing push to try to involve the plastic surgeon particularly for this reason — to try to avoid a defect," but once one develops, options to repair it are limited, Patel said.
The implants sold today are for reconstructing breasts after mastectomies. They aren't designed to fix odd-shaped deformities from lumpectomies or radiation.
"Each one is so different, there's no little thing you can just pop in there," Gutowski explained.
Doctors can try making the other breast smaller so they match, transplanting a back muscle to boost the flawed breast, or rearranging tissue to more evenly distribute what's left. But these involve surgery and leave scars.
Mini implants of fat tissue have been tried, but they often get resorbed by the body or die and turn hard and lumpy. The recent discovery that fat cells are rich in stem cells — master cells that can replenish themselves and form other tissues in the body — renewed interest in their use.
In the Japanese study, doctors liposuctioned fat from 21 breast cancer patients' tummies, hips or thighs. Half was reserved as the main implant material; the rest was processed to extract stem cells and combined with the reserved fat. This was injected in three places around a breast defect.
Doctors think the stem cells will keep the tissue from dying and form lasting mini implants.
Eight months after treatment, "about 80 percent of the patients are satisfied" with the results, said the lead researcher, Dr. Keizo Sugimachi of Kyushu University in Fukuoka, Japan.
There was a statistically significant improvement in breast tissue thickness at one and six months after treatment.
Doctors with no role in the research say longer study is needed to see if these results last.
The treatment is expected to cost $3,000 to $5,000, said Cytori's president, Dr. Mark Hedrick. The company sees potential for cosmetic breast augmentation of healthy breasts, but for now "our plan is to focus on an unmet medical need" in cancer patients, he said.
The American Society of Plastic Surgeons says doctors must be cautious about using fat cells for cosmetic purposes until more is known. Gutowski heads a task force the society formed to study the science. Coleman is a member.
"It's got great potential not only for breast but other cosmetic and reconstructive purposes," like filling in facial defects from cancer or trauma, Gutowski said. "Imagine the aging face."
Better cosmetic treatments may encourage more women to choose lumpectomies. Some have opted for mastectomies because they are concerned about being left with a defect, especially younger women.
Laurie Rapp, a 48-year-old restaurant manager in Philadelphia, was only 32 when she had a lumpectomy, and now has mismatched breasts.
"One is so much smaller than the other one," she said. "There's quite a bit of puckering, and as I'm getting older I feel it's getting worse."
She probably would not try the stem cell treatment now, but if it had been available when she had her surgery, "I definitely would have, especially because I wasn't even married then," she said.
Thank for AP
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