Insights into Epithelial Cell Senescence from Transcriptome and Secretome Analysis of Human Oral Keratinocytes [RNA-seq]

ABSTRACT: Senescent cells are one source of the chronic inflammation that contributes to the diseases and debilities of aging. Whereas cellular senescence in fibroblasts is well documented, how this process is orchestrated in epithelial cells, the origin of human carcinomas, is much less understood. We used normal primary human oral keratinocytes (NOKs) to elucidate senescence programs in a prototype mucosal epithelial cell that undergoes senescence spontaneously. We employed widely-accepted assays to characterize senescence phenotypes in these cells and found that p21WAF1/CIP1 is not a reliable marker of senescence for NOKs, as it is for fibroblasts. We performed transcriptome analysis by RNA-seq and proteomic analysis of secreted proteins, both non-vesicular and those associated with extracellular vesicles (EVs). NOKs, while sharing with fibroblasts certain important aspects of inflammation, such as upregulation of the NF-κB, interferon, and p38MAPK pathways, also exhibit novel senescence associated characteristics. In two of the donors, we observed an expected repression of DNA repair genes, correlating with downregulation of E2F1 mRNA and protein, but saw a divergent result for the third donor. We were able to highlight potential senolytic targets. Our secretome analysis led us to propose additions to the senescence associated secretory phenotype, including HSP60, which we found on the surface of EVs. Moreover, EVs from senescent NOKs can create inflammation by stimulating interferon pathway signaling in THP-1 monocytes in culture. Our results highlight important senescence changes in epithelial cells in terms of how these cells contribute to chronic inflammation, aging, and age-related diseases.

ORGANISM(S): Homo sapiens

PROVIDER: GSE155371 | GEO | 2021/03/18

REPOSITORIES: GEO