Related Experiment Video
Updated: Jan 19, 2026

Evaluating the Effect of SASP Factors on the Proliferation of Cancer Cells Using a Comparative Analysis of Three Distinct Methodologies
Published on: September 19, 2025
Cell division rates decrease with age, providing a potential explanation for the age-dependent deceleration in cancer
Cristian Tomasetti1,2,3, Justin Poling4, Nicholas J Roberts2,5
1Division of Biostatistics and Bioinformatics, Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21205; bertvog@gmail.com ctomasetti@jhu.edu.
Abstract:
A new evaluation of previously published data suggested to us that the accumulation of mutations might slow, rather than increase, as individuals age. To explain this unexpected finding, we hypothesized that normal stem cell division rates might decrease as we age. To test this hypothesis, we evaluated cell division rates in the epithelium of human colonic, duodenal, esophageal, and posterior ethmoid sinonasal tissues. In all 4 tissues, there was a significant decrease in cell division rates with age. In contrast, cell division rates did not decrease in the colon of aged mice, and only small decreases were observed in their small intestine or esophagus. These results have important implications for understanding the relationship between normal stem cells, aging, and cancer. Moreover, they provide a plausible explanation for the enigmatic age-dependent deceleration in cancer incidence in very old humans but not in mice.
Related Concept Videos
Replicative Cell Senescence
Molecular Factors Affecting Cell Division
Several proteins function as internal regulators to ensure each cell cycle stage is completed faithfully before proceeding to the next. Regulator molecules may act directly or influence the activity or production of other...
Adaptive Mechanisms in Cancer Cells
Some of the advantages that cancer cells have on normal cells include - enhanced ability to divide without terminally differentiating, induce new blood vessel formation,...
The Effect of Aging on Tissues
Aging
Cellular Clock Theory
The cellular clock theory posits that the human lifespan is closely tied to the finite capacity of cells to divide, a phenomenon governed by telomeres, which are protective caps at the ends of...
What is the Cell Cycle?

