Limited cell-autonomous anticancer mechanisms in long-lived bats.

Area of Science:

• Gerontology
• Cancer Biology
• Comparative Genomics

Background:

• Bats exhibit exceptional longevity and cancer resistance, exceeding that of most mammals.
• Understanding the cellular mechanisms behind bat longevity and tumor suppression is crucial for aging and cancer research.

Purpose of the Study:

• To investigate the cellular requirements for malignant transformation in fibroblasts from diverse, long-lived bat species.
• To identify potential anti-aging and anti-cancer defense mechanisms in bats.

Main Methods:

• Primary fibroblasts were isolated from four bat species: Myotis lucifugus, Eptesicus fuscus, Eonycteris spelaea, and Artibeus jamaicensis.
• Cells were analyzed for replicative senescence, telomerase activity, secretory phenotype, and susceptibility to oncogenic transformation (p53/pRb inactivation, HRAS activation).
• Gene expression (TP53, MDM2) and apoptosis were assessed, with genomic analysis for TP53 duplication in M. lucifugus.

Main Results:

• Bat fibroblasts do not undergo replicative senescence and express active telomerase.
• They exhibit dampened secretory phenotypes.
• Unlike other long-lived mammals, bat fibroblasts are readily transformed by inactivation of p53 or pRb combined with HRAS activation.
• Elevated TP53 and MDM2 transcripts and increased p53-dependent apoptosis were observed.
• Myotis lucifugus showed TP53 genomic duplication.

Conclusions:

• Bat fibroblasts possess unique cellular properties, including resistance to senescence and active telomerase.
• Enhanced p53 activity, potentially involving genomic duplication, may serve as an anti-cancer mechanism in some bat species.
• The lack of unique cell-autonomous tumor suppression suggests bats might rely on robust in vivo immunosurveillance to prevent cancer.