henhao
Sign in
Cell BiologybioRxiv
Preprint

Chemotherapy-Induced Oral Mucosal Injury Is Defined by p53 Activation, Cell Cycle Arrest and Diverse Epithelial Progenitor Dynamics

Pedro H F SILVA, Lei LiiD, Madison Muriel, Tara Brennan, Md Hasanuzzaman, Mariadela Demoura, Joleene Stampfer, Michele Sveinsson, Christos K FountzilasiD, Jill E. Schabert, Anurag K. Singh, Jonathan BardiD, Nicolas F. SchlechtiD, Laertis IkonomouiD, Patricia I. DiaziD

PDFDOI
In-depth full-text digest available · Jump to digest ↓

Abstract

Chemotherapy-induced oral mucositis is a common and debilitating complication, yet the mechanisms underlying oral mucosa injury and repair remain poorly defined. Using a mouse model of 5-fluorouracil (5-FU)-induced mucositis, we define gene networks and oral mucosal cellular landscape dynamics in response to chemotoxic stress. We show that 5-FU-induced epithelial atrophy is driven primarily by cell cycle arrest rather than apoptosis, despite concurrent activation of p53-dependent transcriptional programs linked to both cell fates within individual cells. Relative to intestine, the recovering oral mucosa exhibits a more effective cell cycle checkpoint response and uniquely undergoes metabolic reprogramming toward lipid oxidation. Single-cell RNA sequencing revealed putative epithelial progenitor populations with distinct responses to chemotherapy, including chemoresistant cells with a p53- and AP-1 complex gene signature, reminiscent of lung transitional cell states. These findings define diverse progenitor dynamics and p53-driven responses as key determinants of oral mucosal injury and repair following chemotherapy.

02 /Specification & Classification

Click any tag to browse matching papers
Citations
0
OpenAlex Topics

In-depth summary

✦ Multi-agent verified full-text synthesis

Claude Sonnet 4.6 · xhigh effort · 8 Nov 2026 · from the full text of version 2 (11 Sept 2026) · CC BY 4.0

In 5-FU-treated mice, oral and intestinal epithelial atrophy stems from p53-linked cell cycle arrest, not apoptosis, while a chemoresistant AP-1/p53 basal cluster expands in tongue.

Mechanisms of oral mucositis are poorly defined, and it was unknown whether oral and intestinal tissues respond to chemotherapy alike or which oral progenitors drive repair. This work compares p53-driven transcription over time in tongue and small intestine, and resolves tongue epithelial subpopulations by single-cell RNA-seq.

Key results

  1. ShownCell cycle arrest, not apoptosis, drives epithelial loss in both tongue and small intestine, although intestinal proliferation recovered less completely than tongue.

    Tongue KI67-positive cells nearly vanished at day 2, recovered from day 4 and normalized by day 10; intestine stayed below normal at day 10. Cleaved Caspase-3 IHC showed no significant increase in either tissue; tongue TUNEL and western blot also found no apoptosis. · Cell cycle arrest is the dominant response to…

  2. ShownSingle epithelial cells co-activate cell cycle arrest and pro- and anti-apoptotic programs after 5-FU, which may explain why apoptosis is not executed.

    Cells co-expressing Cdkn1a and Bax rose in basal and suprabasal compartments; same pattern for Cdkn1a with 9 additional apoptosis genes. BAX/CDKN1A and BAX/pan-BCL2 protein co-staining at D2 and D4 (n = 3 mice per group). · Single tongue epithelial cells upregulate…; Figure legends

  3. SuggestedA basal epithelial cluster with an AP-1 complex and p53 stress signature resists 5-FU and becomes the dominant epithelial population at day 4; its progenitor role is inferred from signatures only.

    Tongue scRNA-seq gave 22 epithelial subclusters. Highly proliferative basal cells were depleted at days 2 and 4; at day 4 all quiescent clusters were depleted except AP-1 cluster 11. C-JUN and ATF3 positive cells were the majority of epithelium at day 4 (n = 3 mice per group). · Single-cell transcriptomics of tongue confirms…; An AP-1 complex–responsive basal epithelial…; Figure legends

  4. ShownTongue and intestine share p53 activation but differ in target usage and metabolism: tongue, not intestine, upregulates fatty acid transport and oxidation genes.

    Cdkn1a significant only at days 1 and 2 in tongue vs all time points in intestine; Fas and Pmaip1 up in tongue only; Bbc3 and Pidd1 intestine only. CPT1C, FABP3, FABP5 protein rose in tongue at D4 (n = 4 mice per group); bulk n = 6 tongue, n = 3 intestine. · Oral and intestinal tissues show common p53…; 5-FU induced p53-dependent but…; Metabolic reprogramming supports epithelial…; Figure legends

  5. ShownThe 5-FU schedule caused progressive epithelium-restricted injury in tongue and intestine, with full epithelial recovery in tongue but only partial restitution in intestine, and no sign of an inflammatory infiltrate.

    Tongue lesions from day 4 to day 10; at least one third of epithelial thickness and half of basal cells lost by day 4, continuing to day 8, restored by day 10 (n = 6 mice per group). CD45-positive cells decreased in oral mucosa. · Evaluation of temporal dynamics of 5-FU–induced…; Figure legends

Methods, data and reproducibility

Mouse 5-FU mucositis time course profiled in tongue and small intestine by histology, immunostaining and bulk RNA-seq (DESeq2, GOseq); tongue dorsum scRNA-seq (PIPseq, Seurat v5 SCTransform) resolved epithelial subclusters and within-cell gene co-expression.

  • Bulk RNA-seq of tongue, 5-FU vs PBS controls, sampled at days 1, 2, 4, 6, 8, 10 · mouse (C57BL/6) · n = n = 6 mice per group
  • Bulk RNA-seq of small intestine, 5-FU vs PBS controls, same time course · mouse (C57BL/6) · n = n = 3 mice per group
  • scRNA-seq of dorsal tongue mucosa, PBS and 5-FU at D2, D4, D8 (shortened 5-FU scheme); 22 epithelial subclusters · mouse (C57BL/6) · n = cells from 2 mice pooled per sample; duplicate pools except D4
  • Tongue and intestine histology and IHC (toluidine blue, H&E, KI67, cleaved Caspase-3, CD45, TUNEL) · mouse (C57BL/6) · n = n = 6 mice per group (H&E panels, Fig. 1D and 1I)
  • Immunofluorescence validation of BAX, CDKN1A, BCL2, ATF3, C-JUN, KRT8, CPT1C, FABP3, FABP5 in tongue · mouse (C57BL/6) · n = n = 3 mice per group; n = 4 for CPT1C and FABPs
  • Prospective observational clinical cohort at Roswell Park for oral mucositis during chemotherapy, followed up to 45 days · human
Methods & tools
STAR, RSEM, DESeq2, GOseq, REVIGO, ENCODE uniform RNA-seq pipeline v1.2.4, PIPseq / PIPSeeker v01.01.07, Seurat v5 (SCTransform, FindMarkers), ImageJ, NIS-Elements AR 6.10.02, GENCODE M21 (mm10), GRCm39-2022.04 reference
Reagents & environment
ENCODE uniform RNA-seq pipeline v1.2.4 (mm10, GENCODE M21); bcl2fastq 2.20.0.422; PIPSeeker v01.01.07 with GRCm39-2022.04; Seurat v5 in R; NIS-Elements AR 6.10.02.
Reproducibility gaps
No code repository or sequencing data accession is reported in the text; results rely on supplemental tables that are referenced but not provided here.
Limitations (4)
  • The study is not mechanistic; p53 control of cell cycle arrest is inferred from expression and staining, and which cell cycle genes mediate atrophy and recovery remains to be dissected. · stated by the authors
  • Dynamics and regenerative capacity of the identified oral epithelial populations, including the AP-1/p53 cluster, require further mechanistic study. · stated by the authors
  • scRNA-seq used pooled samples from 2 mice per library, and D4 was sequenced in a single batch due to low cell numbers, limiting replicate-level statistics; bulk intestine had n = 3 vs n = 6 for tongue. · noted in this summary
  • Progenitor status of the Wnt-responsive and AP-1 clusters rests on gene signatures and similarity to lung transitional cells, with no lineage tracing or functional regeneration test. · noted in this summary

Who should read:Read this if you study chemotherapy-induced mucositis or epithelial regeneration and want tissue-resolved p53 transcriptional dynamics and single-cell progenitor states in mouse tongue.

Reproducibility ledger

Nobody has reported trying to reproduce this paper yet. Did you replicate an experiment or run the code? Your report saves the next lab a week.

Sign in to file a reproducibility report.

Related papers

Similarity Map
SelectedSame fieldCross-field
THISHuang '22Ludikhuize '21Schreurs '26Thorpe '24Moss '26Cantero-Rec '21
62% semantic matchMolecular Biology
Bin Huang, Mengxuan Gui, Jinyan Zhao+4 more·bioRxiv·May 4, 2022