Reverting to single-cell biology: The predictions of the atavism theory of cancer

Cancer or cancer-like phenomena pervade multicellular life, implying deep evolutionary roots. Many of the hallmarks of cancer recapitulate unicellular modalities, suggesting that cancer initiation and progression represent a systematic reversion to simpler ancestral phenotypes in response to a stress or insult. This so-called atavism theory may be tested using phylostratigraphy, which can be used to assign ages to genes. Several research groups have confirmed that cancer cells tend to over-express evolutionary older genes, and rewire the architecture linking unicellular and multicellular gene networks. In addition, some of the elevated mutation rate a well-known hallmark of cancer is actually self-inflicted, driven by genes found to be homologs of the ancient SOS genes activated in stressed bacteria, and employed to evolve biological workarounds. These findings have obvious implications for therapy. (c) 2021 Published by Elsevier Ltd.

Automated summary

Cancer initiation and progression may represent a systematic reversion to simpler ancestral phenotypes in response to stress, a concept known as the atavism theory. Research has shown that cancer cells tend to over-express evolutionary older genes and rewire the architecture linking unicellular and multicellular gene networks. Some cancer hallmarks, such as the elevated mutation rate, may be driven by ancient homologs of SOS genes, activated in stressed bacteria for biological workarounds.