From cancer to rejuvenation: incomplete regeneration as the missing link (Part I: the same origin, different outcomes)

From Autonomy to Integration, From Integration to Dynamically Balanced Integrated Co-existence: Non-aging as the Third Stage of Development

Reversible senescence at the cellular level emerged together with tissue specialization in Metazoans. However, this reversibility (ability to permanently rejuvenate) through recapitulation of early stages of development, was originally a part of ontogenesis, since the pressure of integrativeness was not dominant. The complication of specialization in phylogenesis narrowed this “freedom of maneuver”, gradually “truncating” remorphogenesis to local epimorphosis and further up to the complete disappearance of remorphogenesis from the ontogenesis repertoire. This evolutionary trend transformed cellular senescence into organismal aging and any recapitulation of autonomy into carcinogenesis. The crown of specialization, Homo sapiens, completed this post-unicellular stage of development, while in the genome all the potential for the next stage of development, which can be called the stage of balanced coexistence of autonomous and integrative dominants within a single whole. Here, completing the substantiation of the new section of developmental biology, we propose to call it Developmental Biogerontology.

The Ratio of the Genome Two Functional Parts Activity as the Prime Cause of Aging

The metazoan genome composes of sets of housekeeping genes (HG) for fundamental cellular autonomous processes and integrative genes (IntG) that provide integrative functions and form the body as an integrated whole. The main paradigm for multicellularity development which has been improved in evolution, is the submission of the cellular autonomy to the interests of the integrated whole. Permanent increase of the “functional tax” of IntG-genome (IntG-shift) and epigenetic restriction of autonomy in phylogenesis/ontogenesis is the essence and root cause of aging, inherent in the very nature of highly integrated multicellularity. The regulation of the balance shift toward HG can be managed to eliminate aging and avoid carcinogenesis, which is only due to the irreversibility of this shift. Here we propose the criterion for measuring the functional and biological age of cells and the body as a whole for assessing the effectiveness of any type of palliative geroprotective or radical anti-aging intervention.

From cancer to rejuvenation: incomplete regeneration as the missing link (part II: rejuvenation circle)

In the first part of our study, we substantiated that the embryonic reontogenesis and malignant growth (disintegrating growth) pathways are the same, but occur at different stages of ontogenesis, this mechanism is carried out in opposite directions. Cancer has been shown to be epigenetic-blocked redifferentiation and unfinished somatic embryogenesis. We formulated that only this approach of aging elimination has real prospects for a future that is fraught with cancer, as we will be able to convert this risk into a rejuvenation process through the continuous cycling of cell dedifferentiation-differentiation processes (permanent remorphogenesis). Here, we continue to develop the idea of looped ontogenesis and formulate the concept of the rejuvenation circle.