In cancer cells, the coordination of growth, division and destruction in the cell group is suspended. Regulatory signals are not recognized or not performed because most of the genetic code is required for this defect.
About 5,000 of the 25,000 human genes are responsible for the safe conservation of the genetic code from one cell generation to the next. These so-called oncogenes and tumor suppressor monitor the correct sequence of base pairs in the DNA after each reduplication decide on the need for repair processes to be observed by the cell cycle until the repairs are carried out and where appropriate, initiate a programmed cell death (apoptosis), if the repair does not work.
After today's most plausible theory of cancer development (carcinogenesis), the primary disease event, a change in one of these "guardian genes" is either a copy of rare inborn error or by a mutation. This gene can be monitored by the sub-step is no longer accompany him correctly, that it come in the next generation of cells to more defects can. If a second Wächtergen affected, the effect is potentiated continuously. Although apoptosis genes (eg p53) affected, in such a situation would trigger the programmed cell death, these cells are immortal.
By further changes in the DNA form the cell additional features that make the treatment of the cancer to survive including the ability to lack of oxygen to build up its own blood supply (angiogenesis) or to emigrate from the association and in foreign tissue such as bone, lung or brain to settle (metastasis). Only with this ability to win its deadly potency of cancer: 90% of all cancer patients where the deadly disease starts to die, not by the primary tumor but from its metastases or to sequelae of metastatic disease. The immune system tries
principle, to combat the uncontrolled growing cells. Since these same but in many ways normal body cells that defensive measures are usually not sufficient to control the tumor.
cancer cells are often aneuploid, which means they then have a change in chromosome number. [1] It is the subject of research whether the aneuploidy of cancer cells cause or consequence of disease. This also raises the theory that the development of cancer is not, or not only on the mutation individual genes but is due to the change of the complete set of chromosomes.
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