Cancer and malignant resistance of cells as phenomena of adaptation to damaging factors.
I propose the hypothesis that mechanisms of general biological persistent resistance to damaging factors are closely related to the development of tumour cells. This phenomenon is characteristic of bacterial variants whose resistance to antibiotics and other chemotherapeutic drugs appears through L-transformation. As somatic cells are exposed to carcinogens and develop into tumour cells, they also acquire resistance to the toxic effects of carcinogens through multistage malignant transformation. Many cancerous cells, which have acquired persistent resistance to chemotherapy drugs or irradiation, often reappear locally or in metastases after courses of treatment. Thus, these cells undergo a kind of repeated development of malignancy. After a certain remission period, they begin to multiply more intensively locally, and are more likely to spread by metastasis. All resistant cells have the following characteristics: simplified metabolism, genetic, biochemical and morphological properties; lower requirements from their nutrient medium; rapid growth; parasitic qualities; invasiveness. It is as if they regress into a more primitive mode of existence (atavism) to survive under unfavourable circumstances. Somatic cells, resistant to carcinogens and the cells which undergo progression to more malignant types under the influence of drugs become similar to unicellular organisms or to forms of the latter which are resistant to damaging factors. The more primitive the cells become, the better they survive. Thus, cancer is a special case of the general resistance of cells to damaging factors.
Monceviciute-Eringiene
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Laboratory of Immunology, Lithuanian Oncological Center, Lithuania.
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects / Q000235:genetics; D002273:Carcinogens / Q000633:toxicity; D004352:Drug Resistance, Microbial; D006801:Humans; D007113:Immunity, Innate; D008954:Models, Biological; D009369:Neoplasms / Q000503:physiopathology*
D000900:Anti-Bacterial Agents; D002273:Carcinogens