just specific cells. Virus and bacteria do us good meaning what? Rapid regeneration research are done by studying stem cells.

If all the cellular safeguards of all cells suddenly disappeared, then you’d have cancer…the hard part is flipping the switch back the other way.

Cancer is rare in cell types that themselves rarely divide, such as muscle cells. There are fewer active signals to alter in such cells.

yes… the general rule is higher the rate of cell turnover, the higher the incidence of cancer… another example is that epithelial cancers (carciomas) that are most common because it’s epithelial cells that have a higher rate of cell turnover… this means that the cells are more likely to have accumulation of genetic mutations (i.e. loss of function of tumour suppressor genes and gain of function of oncogenes), which cause loss of control of the cell cycle… this loss of control can causes uncontrolled cellular growth – cancer…

i watched a program just now about an identical twin with acute lymphoblastic leukaemia… in this condition, identical twins have a higher incidence than the general popultation (not the case for most childhood cancers)… this suggests that the pre-cancer starts during foetal development… anyway, the reason i mention it here is that the scientist interviewed stated that the trigger for leukaemia was that lack of exposure to infectious diseases during early age and so the child’s immune system did not develop properly… evidence for this was the drastic increase in leukaemia in easten germany after the berlin wall was knocked down in 1989…