Cancer, a disease of multicellularity / Cancerul, o boala a multicelularitatii

Cancer re-creates within our own bodies the evolutionary process that enables animals to adapt to their environment. At the level of organisms, natural selection operates when genetic mutations cause some organisms to have more reproductive success than others; the mutations get “selected” in the sense that they persist and become more common in future generations. In cancer, cells play the role of organisms. Cancer- causing changes to DNA cause some cells to reproduce more effectively than ordinary ones. And even within a single tumor, more adapted cells may outcompete less successful ones. “It’s like Darwinian evolution, except that it happens within an organ.

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Cancerul recreeaza in interiorul organismului procesul evolutiv care le permite animalelor sa se adapteze mediului de viata. La nivel individual, selectia naturala opereaza cand mutatiile genetice determina anumite organisme sa aiba un succes reproductiv mai mare decat altele. Mutatiile sunt selectate in sensul ca ele persista si devin mai raspandite in generatiile viitoare. In cancer, celulele joaca rolul indivizilor, al organismelor. Cancerul, cauzand modificari ale ADN-ului, determina anumite celule sa se divida mai eficient decat cele normale. Chiar si in interiorul aceleieasi tumori, celulele mai adaptate pot elimina celulele mai putin adaptate. Este o evolutie darwiniana, cu exceptia faptului ca se desfasoara in interiorul unui organ.