title: Carcinogenesis--devolution towards an ancient nucleated pre-eukaryotic level.
abstract: Because the mitochondria and the cells housing them are obligatory symbionts, the evolutionary history of cells forms the locus minoris resistentiae which is the prerequisite for the carcinogenetic process. During carcinogenesis, the cells devolve towards an ancient anaerobic nucleated pre-eukaryotic level. True carcinogens cause an accumulation of inclusion bodies in the inner, bacterial, mitochondrial membrane. The mitochondrial damage which is detectable only in the early pretumorous stages, results in the respiratory surface with its enzymes being specifically changed, the mitochondrial and nuclear cycles no longer coinciding, the energy generation being forced to reuse the latent, "prehistoric", mode of respiration and the mitochondrial enzyme systems of soil bacterial origin becoming adapted to use other and more versatile metabolic pathways with a wider variety of end-products than classical glycolysis which produces lactate only. Neither external carcinogens nor oncogens are necessary. An increased, prolonged cell replication activity of physiological type is sufficient to initiate and maintain the process in animals with an inherited neoplastic disposition located in the inner mitochondrial membrane. The neoplastic disposition is inherited maternally: in fertilization the ovum does not receive mitochondria from the spermatocyte. The final results are an overall retardation of cell processes and instability in its structural and functional repertoire, the cytoskeleton (differentiation organelle) of the malignant cell manifesting special patterns. The proposed devolutionary mechanism is feasible as DNA packages are physiological components of soil bacterial membrane and can remain dormant (repressed) for years, or for ever, but under suitable conditions can generate seemingly new species, and particularly because enzyme adaptability is the unique privilege of soil bacteria.
mesh_terms: D000818:Animals; D005075:Biological Evolution; D002273:Carcinogens / Q000494:pharmacology; D002454:Cell Differentiation; D004734:Energy Metabolism; D005057:Eukaryotic Cells / Q000502:physiology; D006801:Humans; D051379:Mice; D008928:Mitochondria / Q000502:physiology*; D008938:Mitosis; D009369:Neoplasms / Q000473:pathology* / Q000503:physiopathology; D011230:Precancerous Conditions / Q000473:pathology; D012867:Skin / Q000187:drug effects; D012878:Skin Neoplasms / Q000209:etiology / Q000473:pathology; D014867:Water
chemical_list: D002273:Carcinogens; D014867:Water