Study shows that mutations in 1 gene cause many cancers
An important gene that normally protects the body against cancer can itself cause a variety of cancers depending on the specific mutation that damages it, according to a new study by investigators at the Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC-James).
The study examined mutations in a gene called PTEN. People who inherit a mutated copy of this gene have Cowden syndrome, a condition that carries a high risk of cancer in a number of organs, including the breast, thyroid and ovary. In addition, PTEN is frequently mutated in normal body cells leading to prostate, lung and pancreatic cancers.
Why people with Cowden syndrome develop different cancers, or cancers that are more severe in some than in others, is unknown, though the cause is often attributed to the natural genetic differences that exist between individuals.
This animal study, however, linked specific mutations in the gene to distinct kinds of cancer in organs targeted by the syndrome.
"We showed that the mutations themselves play a critical role in driving the cancers that occur in certain organs in people with Cowden syndrome," says principal investigator Gustavo Leone, associate professor of molecular virology, immunology and medical genetics at the OSUCCC-James. ...
via Study shows that mutations in 1 gene cause many cancers.
Why metastasic cells migrate
One of the most intriguing questions in cancer research is what causes metastatic tumour migration, why some tumour cells manage to migrate to other parts of the body but others cells don't. International investigation conducted by Enrique MartÃn Blanco, CSIC researcher at the Institute of Biology of Barcelona, located in the Barcelona Science Park, reveals that cells make use of a natural mechanism for this. It happens to be a family of proteins that trigger cell migration in normal processes such as growth or healing. Nevertheless, this mechanism had never been identified before in healthy cells. ... Martin-Blanco adds that "now we can study this mechanism in healthy cells, and we hope to discover more about the conditions that can inhibit or accelerate it." They expect not only to understand better this mechanism but also to find alternative strategies to inhibit metastasis. - ea
But why are we always so far from a cure?
I am not personally working my hardest to understand aging. I am not working to find a cure for cancer. I am not working with cellular therapy as a possible cure for heart disease. At times I think I should dedicate the rest of my life to the study of how to prolong life! ( Yes, overpopulation is one of our biggest problems, but it is an entirely different problem. If you make death by old age optional, the people living would be forced to make better decisions with regard to the planet and resource use. )
Medical science is a complete failure at preventing death. The death rate is still 100%. No animal (other than the immortal jelly fish, turritopsis nutricula) has ever escaped eventual death from old age. Luckily, many people are working on the problem.
I just gave SENS a $50 donation using PayPal. Not much, but every little bit helps, and the way I see it, what you donate today may save your life in a few years.
SENS Foundation was founded to develop, promote and ensure widespread access to regenerative medicine solutions to the disabilities and diseases of aging. Our focus is the Strategies for Engineered Negligible Senescence (SENS) identified by our Chief Science Officer, Dr Aubrey de Grey, and combining direct research efforts with education, affiliation and outreach programs. - sens
We have made progress. We understand aging much better now.
“Aging occurs because the complex biological molecules of which we are all composed become dysfunctional over time as the energy necessary to keep them structurally sound diminishes. Thus, our molecules must be repaired or replaced frequently by our own extensive repair systems,” Hayflick said.
“These repair systems, which are also composed of complex molecules,” he explained, “eventually suffer the same molecular dysfunction.
“The time when the balance shifts in favor of the accumulation of dysfunctional molecules is determined by natural selection — and leads to the manifestation of age changes that we recognize are characteristic of an old person or animal. It must occur after both reach reproductive maturity, otherwise the species would vanish.” - seniorjournal
It seems to me that with enough time, energy and equipment, I could figure out how to extract my own stem cells and grow new organs. As biogerontologist Aubrey de Grey points out once we can grow replacement parts we can keep our bodies youthful for many centuries. This was from 1995:
Using a patient's own heart muscle cells as seeds for new tissue, researchers are testing a novel technique to "grow" replacement heart valves Christopher K. Breuer, a physician at Children's Hospital in Boston, says the new method for engineering heart valve tissue could offer an alternative to animal-derived or mechanical devices. "Tissue-engineered heart valves do not have many of the problems associated with today's replacement valves and may some day offer an improvement over today's state-of-the-art therapy," Breuer said last week at a meeting of the American Chemical Society in Anaheim, Calif. In the United States, physicians replace approximately 60,000 heart valves each year, mostly with plastic prostheses, infections, or rejection, Breuer says. Artificial valves last only 10 to 20 years, creating problems not only for children who have heart operations, but also for adults who need new heart valves at age 40 and may have to face a second operation at age 50 or 60. ... To engineer the valve, a physician removes a small piece of tissue from a patient's heart, then cultures the cells in a laboratory, separating them into the three cell types found in valves: smooth muscle, endothelial, and fibroblast. Those cells are then implanted into a biodegradable material, polyglycolic acid polyglycolic acid, which surgeons already use in dissolvable sutures, Breuer says. The material serves as a scaffold, enabling the cells to form living valve tissue. After 6 weeks, the foreign material dissolves completely, leaving in its place a biological valve that resembles natural heart tissue. Breuer says that he and his colleagues are "evaluating the biomechanical properties of these structures and comparing them to native heart valve tissue." The research team estimates that many of the 2,300 patients who receive heart transplants every year could potentially benefit from this research, as could the 40,000 patients who need, but cannot get, replacement hearts, owing to a limited supply of donor organs. So far, the researchers have tested the procedure in lambs, with good results, Breuer reports. However, the valves will require more research and development before any testing can begin in humans. - thefreelibrary
This was from Sep 2, 2007, so we should be able to grow new heart tissue from our own stem cells in a few years... if not now...
Surgeons will soon be able to literally mend a broken heart using live tissue grown from a patient's very own stem cells, top cardiologists said Monday. The whole procedure -- harvesting cells from bone marrow, growing tissue, and surgically implanting the heart muscle or valve -- could take as little as six weeks and could become routine within three-to-five years, they reported. Their findings were published in a special issue of the Philosophical Transactions of The Royal Society B in Britain. One reason heart attacks are so debilitating, even when they are not fatal, is because the human heart -- a massive muscle surrounding four valves controlling the body's blood flow -- does not regenerate. Damaged tissue stays damaged. Most problems occur with age, when the old ticker simply begins to wear out. "But the highest medical need for tissue-engineered heart valves is in the treatment of congenital heart malformation," which affects nearly one percent of all newborns, Simon Hoeurstrup, lead author of one of the studies, told AFP. Artificial heart valves currently available must be periodically replaced as children grow, leading to great suffering and higher death rates than in adults. Bio-engineered heart muscle that could be grafted onto a patient's living tissue without fear of rejection by the immune system has long been a holy grail of cardiovascular medicine. Artificial replacements "do the job and save people's lives," said celebrated heart surgeon Magdi Yacoub, who coordinated the 20-odd studies. "But they cannot match the elegant, sophisticated functions of living tissues." While durable, mechanical hardware increases the risk of bacterial infection in the heart's inner lining, as well as abnormalities in blood flow. Recipients must also take medication to prevent blood clots, boosting the chances of internal bleeding and embolisms. Cardiovascular disease, the number one killer worldwide, claimed some 17.5 million lives in 2005, according to the World Health Organisation. Many of these deaths might have been avoided by timely surgery to implant replacement valves and heart muscle. ... In the tissue engineering approach favored by Yacoub and Hoerstrup, the patient's own stem cells -- taken from bone marrow -- are isolated and expanded in the laboratory using standard cell culture techniques. They are then "seeded" onto a special matrix in the shape of a heart valve that is positioned in a device called a "bioreactor" that tricks the cells into growing in the right shape. Once mature, the living-tissue heart valves can be implanted in the patient. The whole process unfolds in a matter of weeks. - ap
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