REGARDING RHABDOMYOSARCOMA(Apparently a cancer of myoblasts)According to Wikipedia (http://en.wikipedia.org/wiki/Rhabdomyosarcoma), rhabdomyosarcoma is cancer of skeletal muscle precursor cells (myoblasts, rather than cancer of myotubes = mature multinucleate skeletal muscle cells.) This article is worth reading, and matches what I have previously read in medical textbooks. However, my confidence is undermined by statements like the following "Most occur in areas naturally lacking in skeletal muscle, such as the head, neck, and genitourinary tract.", because lots of skeletal muscle occurs in the head and neck. This article doesn't mention that normal skeletal muscle cells are highly multinucleate, or that muscle cell precursors normally have only one nucleus per cell. It also doesn't attempt to find out whether rhabdomyosarcoma cells have one nucleus per cell, or many nuclei per cell. That could be very important in relation to medical treatment of this kind of cancer. In particular, if rhabdomyosarcoma cells have one nucleus per cell, then maybe they could be prevented from further cell division by fusing cells together, or by preventing cytokinesis (so that cells become binucleate. The drug cytochalasin might turn out to be a cure, and I am surprised that more attention isn't being given to these (fairly obvious) questions and possibilities. Don't assume that "They" have tried everything, or even that "They" have much understanding of basic biological phenomena. Incidentally. there is a kind of cancer called "Neuroblastoma" which is a cancer of nerve cell precursors. When these cells are induced to become nerve cells and extend axons, then they can't synthesize DNA any more, which can cure the cancer, by converting it into what amounts to a giant ganglion. http://sarcomahelp.org/rhabdomyosarcoma.html contains more information, a large bibliography of 87 journal articles, and the following important statements "The defining characteristic of RMS is the demonstration of evidence of skeletal muscle lineage - either by its appearance under the microscope or by the pattern of chemical staining ("immunostaining") "Nearly 90% of cases of alveolar RMS will have a characteristic translocation involving one of the "PAX" genes (most commonly the PAX 3 gene, located on chromosome 2, less commonly the PAX 7 gene, located on chromosome 1) and the "forkhead" (FKHR) gene (located on chromosome 13). Unfortunately, neither of the histological sections (figures #6 and #7) look the slightest bit like muscle tissue (to me at least). If these slides had been observed through a polarized light microscope, then striated muscle it would have been dramatically clear. Nowhere in this long paper is it mentioned that skeletal muscle cells are multinucleate, that myoblasts have only one nucleus, or that further division normally is prevented when as many as two myoblast nuclei are in the cytoplasm. It is fair to say that this field needs researchers with more knowledge in basic biological facts about muscle development. Maybe you could invent a cure based on fusion between groups of rhabdomyosarcoma cells. Also, notice the following quote from this article: "Because of the dependency of RMS on IGF-II, promising new drugs have been developed that either block the interaction of the type I IGF receptor with IGF-II, or that block the downstream biological effects that occur after IGF-II binds to its receptor." In other words: repress the causes, rather than selectively killing those cells with the key abnormality. I think this is the wrong approach, but that MDs are strongly attracted to suppression of symptoms. So are pharmaceutical companies, which might be because patients would need to keep taking the drug forever. In the next paragraph the article proposes making monoclonal antibodies specific for the translocated gene, although I assume the author must mean antibodies specific for the abnormal "fusion protein" that the translocated genes code for. These researchers are doing their best, but you can see how much they need more basic biology.
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