Progress towards a unified theory of the mechanisms of carcinogenesis: role of epigenetic mechanisms.
The common element in the induction and progression of tumors by all types of carcinogens may be the random unmasking of embryonic and nonembryonic genes to produce a cell with characteristics that are not well regulated in differentiated tissue and thus exhibit relatively autonomous growth. The neoplastic state is heritable in the same manner as any other differentiated state. Carcinogens act by disrupting the structure of the chromatin DNA-protein-RNA complex and thus changing the differentiation state of the cell. Survival of the neoplactic cells selects for those gene expressions which aid the autonomous neoplastic state. Some mutations may cause alterations that permit unmasking of genes.
D002273:Carcinogens / Q000494:pharmacology; D002454:Cell Differentiation; D002462:Cell Membrane / Q000378:metabolism; D002471:Cell Transformation, Neoplastic; D002843:Chromatin / Q000378:metabolism; D003260:Contact Inhibition; D004273:DNA, Neoplasm / Q000378:metabolism; D004279:DNA, Viral / Q000378:metabolism; D005796:Genes; D006801:Humans; D007364:Intercalating Agents / Q000378:metabolism; D008954:Models, Biological; D009154:Mutation; D009369:Neoplasms / Q000235:genetics*
D002273:Carcinogens; D002843:Chromatin; D004273:DNA, Neoplasm; D004279:DNA, Viral; D007364:Intercalating Agents