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Scientists Calculate the Speed of Death In Cells And It's 30 Micrometers Per Minute (livescience.com)
An anonymous reader quotes a report from Live Science: Scientists found that death travels in unremitting waves through a cell, moving at a rate of 30 micrometers (one-thousandth of an inch) every minute, they report in a new study published Aug. 10 in the journal Science. That means, for instance, that a nerve cell, whose body can reach a size of 100 micrometers, could take as long as 3 minutes and 20 seconds to die. Apoptosis -- or programmed cell death -- is necessary for clearing our bodies of unnecessary or harmful cells, such as those that are infected by viruses. It also helps shape organs and other features in a developing fetus.
To figure this out, Ferrell and his team observed the process in one of the larger cells present in nature: egg cells of Xenopus laevis, or African clawed frogs. They filled test tubes with fluid from the eggs and triggered apoptosis, which they watched unfold by tagging involved proteins with fluorescent light. If they saw fluorescent light, it meant apoptosis was taking place. They found that the fluorescent light traveled through the test tubes at a constant speed. If apoptosis had carried on due to simple diffusion (the spreading of substances from an area of high concentration to one of low concentration), the process would have slowed down toward the end, according to the study. Since it didn't, the researchers concluded that the process they observed must be "trigger waves," which they likened to "the spread of a fire through a field." The caspases that are first activated, activate other molecules of caspases, which activate yet others, until the entire cell is destroyed.
To figure this out, Ferrell and his team observed the process in one of the larger cells present in nature: egg cells of Xenopus laevis, or African clawed frogs. They filled test tubes with fluid from the eggs and triggered apoptosis, which they watched unfold by tagging involved proteins with fluorescent light. If they saw fluorescent light, it meant apoptosis was taking place. They found that the fluorescent light traveled through the test tubes at a constant speed. If apoptosis had carried on due to simple diffusion (the spreading of substances from an area of high concentration to one of low concentration), the process would have slowed down toward the end, according to the study. Since it didn't, the researchers concluded that the process they observed must be "trigger waves," which they likened to "the spread of a fire through a field." The caspases that are first activated, activate other molecules of caspases, which activate yet others, until the entire cell is destroyed.
In cancer these pathways are generally broken. They are also broken in some non-cancerous tumors, but if they aren't growing out of control in addition to refusing to die they don't cause many issues. One of the first things a virus will try to do will be to prevent the cells from killing themselves, which is why viral infection is associated with some cancers. You probably can't fix these cells post hoc, although inducing better T cell response to cancers is promising.