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Updated: May 21, 2026
07:29
Characterization of In Vitro Differentiation of Human Primary Keratinocytes by RNA-Seq Analysis
Published on: May 16, 2020
Functional interplay between p63 and p53 controls RUNX1 function in the transition from proliferation to
I Masse1, L Barbollat-Boutrand, M Molina
1Centre de Génétique et de Physiologie Moléculaires et Cellulaires, CNRS UMR5534-Université Lyon I, 43 Bd du 11 Novembre 1918, F-69622 Villeurbanne, France. ingrid.masse@univ-lyon1.fr
Cell Death & Disease
|June 8, 2012
Summary
The transcription factor RUNX1 is crucial for skin cell homeostasis, with its expression tightly controlled by ΔNp63 and p53. This regulation impacts keratinocyte proliferation and differentiation, and RUNX1 is altered in skin cancers.
Area of Science:
- Cell Biology
- Dermatology
- Molecular Biology
Background:
- The interfollicular epidermis requires balanced proliferation and differentiation for continuous renewal.
- The transcription factor ΔNp63 plays a critical role in regulating these epidermal processes.
- Previous studies indicated ΔNp63 regulates RUNX1 in mouse keratinocytes.
Purpose of the Study:
- To investigate the role of RUNX1 in human interfollicular epidermis.
- To elucidate the regulatory mechanisms of RUNX1 expression by ΔNp63 and p53 in human keratinocytes.
- To explore the functional impact of RUNX1 on keratinocyte proliferation and differentiation.
Main Methods:
- Analysis of RUNX1 expression in normal human epidermis and skin cancer.
- Chromatin immunoprecipitation assays to assess ΔNp63 and p53 binding to RUNX1 regulatory DNA.
- Quantitative PCR and Western blotting to measure gene and protein expression.
- Functional assays to evaluate the effects of RUNX1 on keratinocyte proliferation and differentiation.
Main Results:
- RUNX1 is expressed in normal human epidermis and its expression is regulated during keratinocyte differentiation.
- ΔNp63 directly binds to RUNX1 regulatory sequences, modulating its expression in a differentiation-dependent manner.
- RUNX1 inhibits keratinocyte proliferation and promotes KRT1 expression, a marker of differentiation.
- RUNX1 expression is altered in basal cell carcinoma and squamous cell carcinoma, mirroring ΔNp63 and p53 expression patterns.
- ΔNp63-mediated regulation of RUNX1 is dependent on p53, involving differential binding to regulatory elements.
Conclusions:
- The interplay between ΔNp63 and p53 is essential for precise control of RUNX1 transcription.
- RUNX1 acts as a key regulator of keratinocyte proliferation and differentiation.
- Dysregulation of the ΔNp63-p53-RUNX1 axis contributes to skin cancer development, highlighting its importance in epidermal homeostasis.
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