The ecology of cancer prevalence across species: Cancer prevalence is highest in desert species and high trophic levels

Abstract

The ecology in which species live and evolve likely affects their health and vulnerability to diseases including cancer. Using 14,267 necropsy records across 244 vertebrate species, we tested if animals in low productivity habitats, with large habitat range, high body temperature and weight-inferred estimates of metabolic rates, and in high trophic levels (from lowest to highest: herbivores, invertivores, primary carnivores, and secondary carnivores) are linked with having increased prevalence of neoplasia. This study found that: (1) habitat productivity negatively correlated with the prevalence of malignancy and neoplasia across tissues, and malignancy and neoplasia in gastrointestinal tissues; (2) inferred metabolic rates negatively correlated with the prevalence of neoplasia; and (3) trophic levels positively correlated with malignancy and neoplasia prevalence in both mammals and non-mammals. However, only the correlations with trophic levels remained significant after Bonferroni corrections for multiple testing. There are several mechanisms that might explain these findings, including the biomagnification of carcinogens in higher trophic levels, as well as tradeoffs between cancer suppression versus reproduction and survival in low productivity environments.

Life history and cancer in birds: clutch size predicts cancer

“…The data represent over 25 years of pathology records from 25 different institutions using 5,499 individual necropsies, including descriptions of age at death of 1287 individuals from 51 species, and malignancies and benign tumors across 108 bird species across 24 different avian orders managed under human care 34 . We measured malignancy prevalence and neoplasia prevalence (benign and malignant tumor) for each species by dividing the total number of necropsies reporting malignancies (or neoplasms) by the total number of 6 necropsies available for that species (supplementary data); a measurement also used in previous studies 9,35 .…”

“…Evolutionary biology has also been an important component of cancer research over the last 50 years 3, 7 . The ecological conditions under which organisms evolved have shaped their responses to various diseases, including cancer 8, 9 . Understanding why organisms differ in their ability to suppress cancer, as well as how they respond to neoplastic expansion, is a central question in comparative cancer research.…”

Cell-in-cell phenomena across the tree of life

“…First, among mammals, Carnivora only have the endotheliochorial placental type (where some of the mother's uterine epithelial cells have entered trophectoderm cells of the blastocyst via entosis 56 ) 176 . Second, among mammals, Carnivora have the highest cancer prevalence/risk [177][178][179] . Since the origin of this gene, ~1.5 billion years ago, another gene phg1A, a homolog of TM9SF4, has been found in facultatively multicellular extant amoeba Dictyostelium discoideum playing a role in phagocytosis 9,83,180 .…”

The relationship between diet, plasma glucose, and cancer prevalence across vertebrates

“…Other variables such as low habitat productivity (i.e., grams of glucose produced in the habitat of species per square meter per year), and low inferred metabolic rates are also correlated with cancer or neoplasia prevalence across vertebrates, but the correlations were not significant after False Discovery Rate corrections for performing multiple tests 13 . There is extensive evidence that diet affects cancer risk in humans [14][15][16] .…”

“…Recently, researchers have begun investigating the role of diet in species' susceptibility to cancer. Within mammals [17][18][19] and across vertebrates 13 , higher trophic levels have higher cancer and neoplasia prevalence.…”