|MadSci Network: General Biology|
This is quite a coincidence. The first day I worked in the fly lab, I asked my postdoc this exact question, and he gave the answer you suggested - that insects don't live long enough to get cancer. However, you raise a good point. Do long-lived insects get cancer? It's definitely possible to cause even short-lived insects to get cancer by mutagenizing them. The fruit fly Drosophila melanogaster only lives three weeks, but a paper came out in _Cell_ on the subject of fruit fly cancer just last month.  The researchers discovered a mutant fruit fly that spontaneously develops tumors. So, given that some mutations can cause insects to get cancer, it should be possible for any insect that lives long enough to develop such mutations to get cancer. And given the large numbers of insects in, say, a termite mound, and the number of genes that could produce uncontrolled cell division when mutated, cancer seems not only possible, but probable. We just don't notice a few termites more or less. (An excellent question, by the way. Insects are excellent model systems, and knowledge about spontaneous cancer in insects could prove extremely useful.) Paul Nagami Undergraduate California Institute of Technology Reference:  Lai, Wei, Shimizu et al. (2005) Control of cell proliferation and apoptosis by Mob as tumor suppressor, Mats. Cell 120:675-685
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