Posted on 09/07/2006 2:21:33 AM PDT by neverdem
Biologists have uncovered a deep link between life span and cancer in the form of a gene that switches off stem cells as a person ages.
The critical gene, well known for its role in suppressing tumors, seems to mediate a profound balance between life and death. It weighs the generation of new replacement cells, required for continued life, against the risk of death from cancer, which is the inevitable outcome of letting cells divide.
To offset the increasing risk of cancer as a person ages, the gene gradually reduces the ability of stem cells to proliferate.
The new finding, reported by three groups of researchers online yesterday in Nature, was made in a special breed of mice that lack the pivotal gene, but is thought likely to apply to people, as well.
The finding suggests that many degenerative diseases of aging are caused by an active shutting down of the stem cells that renew the body’s various tissues and are not just a passive disintegration of tissues under daily wear and tear. “I don’t think aging is a random process — it’s a program, an anticancer program,” said Dr. Norman E. Sharpless of the University of North Carolina, senior author of one of the three reports.
The other senior authors are Drs. Sean J. Morrison of the University of Michigan and David T. Scadden of the Harvard Medical School.
The full implications are far from clear, but the finding that the cells are switched off with age does not seem too encouraging for researchers who hope to use a patient’s own adult stem cells to treat disease. That result may undercut opponents of research on human embryonic stem cells who argue that adult stem cells are enough to build new tissue.
Dr. Sharpless said his finding showed the...
(Excerpt) Read more at nytimes.com ...
Increasing p16INK4a expression decreases forebrain progenitors and neurogenesis during ageing
p16INK4a induces an age-dependent decline in islet regenerative potential
Maybe we are at an impasse, philosophically speaking, in the quest for physical immortality.
Darn, I hate it when that happens!
US Government to Authorize Nazi-Like Human Experiments
Controversial blood trial continues
FReepmail me if you want on or off my health and science ping list.
SC ping
I doubt if there is such a thing as a single gene. There seem to be a number of feedback mechanisms in the cells, so that if something goes wrong, programmed cell death occurs.
An exciting find has been the sirtuin 1 gene, resveratrol, and the mechanical matrix of proteins that surrounds the DNA and protects it from damage and oxidants.
Also exciting is the findings about Vitamin D being a mediator in cell splitting and how it seems to have a role in regulating DNA copying.
Just had my yearly SCI exam.
Everything looks good, but there's some deterioration around the damaged vertebrae.
It looks like my time has passed, but I have great hope for the future of adult stem cell research, and it's help for the next generation of SCI injured, and pray for a medical treatment that will keep others from suffering my fate.
Well Airborne, you get a hat tip from me. Add to that a salute.
I read your background and it seems that you have done VERY well, regardless of the trials and tribulations that have come your way.
I love science, and right now my focus is on learning more about medical research. So much of it is very exciting and yes, much of it will be for the next generations.
However, regardless of all the science in the world, attitude is what it takes to survive...and you obviously have that.
God Bless, thanks and keep the faith..........
Thank you for your kind words.
God has a plan for me.
I'm not sure what it is, but while I search for His plan for me, I'll keep on striving to do right by Him.
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