Four Cases of Spontaneous Neoplasia in the Naked Mole-Rat (Heterocephalus glaber), A Putative Cancer-Resistant Species

Abstract

The naked mole-rat (Heterocephalus glaber) is widely acclaimed to be cancer-resistant and of considerable research interest based on a paucity of reports of neoplasia in this species. We have, however, encountered four spontaneous cases of neoplasia and one presumptive case of neoplasia through routine necropsy and biopsy of individuals in a zoo collection of nonhybrid naked mole-rats bred from a single pair. One case each of metastasizing hepatocellular carcinoma, nephroblastoma (Wilms' tumor), and multicentric lymphosarcoma, as well as presumptive esophageal adenocarcinoma (Barrett's esophagus-like) was identified postmortem among 37 nonautolyzed necropsy submissions of naked mole-rats over 1-year-old that were submitted for necropsy between 1998 and August 2015. One incidental case of cutaneous hemangioma was also identified antemortem by skin biopsy from one naked mole-rat examined for trauma.

Molecular signatures of longevity: Insights from cross-species comparative studies

“…Naked mole rats are also remarkably resistant to cancer, based on multi-year observations of this species’ large colonies (Buffenstein, 2008) and transfection of naked mole rat fibroblasts with activated Ras and SV40 LT to induce oncogenic transformation (Seluanov et al, 2009). Nevertheless, cancer is possible in this species, as recently shown (Delaney et al, 2016; Taylor et al, 2017). Sequencing of the genomes of the naked mole rat (Kim et al, 2011) and a closely related species, the Damaraland mole rat (Fang et al, 2014b), as well as a number of cellular and biochemical studies begin to shed light on the mechanisms for their cancer resistance and long lifespan (Azpurua et al, 2013; Seluanov et al, 2009; Tian et al, 2013).…”

Molecular Mechanisms Determining Lifespan in Short- and Long-Lived Species

“…Cancer-related mortality can reach up to 90% in mice, which have a maximum lifespan (MLS) of 4 years [22]. In contrast, the similar-sized naked mole rat ( Heterocephalus glaber ), which has an MLS of 32 years, rarely develops cancer [23, 25, 26], furthermore naked mole rat cells are resistant to experimental tumorigenesis [27, 28]. Another long-lived rodent, the blind mole rat ( Spalax sp.…”

Rodentia

“…Naked mole-rats are a popular zoo species and are heralded as animal models for cancer and aging due to their extreme longevity and purported cancer resistance. Rare cases of neoplasia have been reported in naked mole-rats and in the related Damaraland mole-rat, which is also longlived and appears to be relatively resistant to cancer and agerelated diseases (Delaney et al, 2016b;Taylor et al, 2016,). Other subterranean rodents used as animal models for carcinogenesis research include some members of Spalacidae (mole-rats, blind mole-rats, zokors, and bamboo rats).…”