Slashdot Mirror
Tumor-suppressing Gene Contributes to Aging
Van Cutter Romney writes "Scientists have discovered a tumor suppressing gene which also leads to aging in stem cells. The gene also known as p16INK4a when removed from 'knockout' mice resulted in older mice having organs as healthy as younger ones. However they didn't live any longer than normal mice. The new study was confirmed by three independent researchers from Harvard, UNC Chapel Hill and University of Michigan."
No, it is different. In the story a year ago, a korean group found that if you suppress telomerase in cancer cells--an enzyme that makes cells 'immortal' by continually adding repeats of bases on to the ends of chromosomes--the cells die. the summary on the slashdot page is not exactly correct--telomerase is not an enzyme specific to cancer cells. In this present work, it is a gene that, in a way, computes a differential equation--weighing the importance of replacing cells using stem cells from its cache against the risk that the replication of cells will result in a cancerous cell. "To offset the increasing risk of cancer as a person ages, the gene gradually reduces the ability of stem cells to proliferate." it is a fundamentally different story and is interesting.
The first thing that needs to fail is the proofreading enzymes, so that a gene or two are damaged without being repaired.
Then the "self destruct" needs to fail to activate in a cell, The self destruct is almost always armed and ready to go, unless it gets knocked out by a "lucky" mutation.
Even if the self destruct fails, the cell sensing needs to fail in order to grow beyond a few cells. Then the telemorase halting needs to fail in order for the cancer to reach something larger than a mole.
The immune system is a last resort, and not a very good one in comparison.
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