On the role of p53 in the cellular response to aneuploidy

• DOI: 10.1016/j.celrep.2021.108892
• Publication Date: 2021-03-23T17:50:42Z
• Authors: Akshay Narkar; Blake A. Johnson; Pandurang Bharne; Jin Zhu; Veena Padmanaban; Debojyoti Biswas; Andrew Fraser; Pablo A. Iglesias; Andrew J. Ewald; Rong Li
• Keywords: p53; 570; QH301-705.5; Colon; Mitosis; Cell Cycle Proteins; Protein Serine-Threonine Kinases; Article; Cell Line; Mice; 03 medical and health sciences; Cell Adhesion; Animals; Humans; aneuploidy; Biology (General); organoids; mitosis; Mammals; 0303 health sciences; G1 arrest; Cell Cycle Checkpoints; Protein-Tyrosine Kinases; Aneuploidy; Mice, Inbred C57BL; Organoids; Tumor Suppressor Protein p53

Most solid tumors are aneuploid, and p53 has been implicated as the guardian of the euploid genome. Previous experiments using human cell lines showed that aneuploidy induction leads to p53 accumulation and p21-mediated G1 cell cycle arrest. We find that adherent 2-dimensional (2D) cultures of human immortalized or cancer cell lines activate p53 upon aneuploidy induction, whereas suspension cultures of a human lymphoid cell line undergo a p53-independent cell cycle arrest. Surprisingly, 3D human and mouse organotypic cultures from neural, intestinal, or mammary epithelial tissues do not activate p53 or arrest in G1 following aneuploidy induction. p53-deficient colon organoids have increased aneuploidy and frequent lagging chromosomes and multipolar spindles during mitosis. These data suggest that p53 may not act as a universal surveillance factor restricting the proliferation of aneuploid cells but instead helps directly or indirectly ensure faithful chromosome transmission likely by preventing polyploidization and influencing spindle mechanics.