Tumour suppression and subdual of cancer (tussc) in elephants: An in vitro study to shed light on Peto’s paradox
Abstract
Logic would suggest that cancer incidence is related to body mass and longevity. Gigantic
animals such as elephants with a longer lifespan (more lifetime of cell divisions) and a larger
body size (more cells) will have more time during their lifetime to accumulate a cancer-causing
mutation in comparison to small-bodied, short-lived animals, such as mice. However, several
studies and the mere existence of large-bodied, long-lived mammals such as elephants and
whales, suggest that there is no correlation between body mass, lifespan and cancer incidence
across different mammalian species. This is a phenomenon known as Peto’s paradox. As there
is a selection for large body size in evolution, there is likely also a selection for cancer
suppression mechanisms that allow an organism to grow large and reproduce successfully. One
of the rationales in the African savanna elephant (Loxondonta africana) is the duplication of a
crucial tumour suppressor gene (TP53) encoding the tumour protein 53 (p53).