Cited by 56Skin Protection and AgingCell death mechanisms and regulationDNA Repair Mechanisms

Evidence for a novel anti-apoptotic pathway in human keratinocytes involving the aryl hydrocarbon receptor, E2F1, and checkpoint kinase 1

Open access
Frauenstein, K, Sydlik, U, Tigges, J, Majora, M, Wiek, C, Hanenberg, H, Abel, J, Esser, C +3 more·2013·Cell Death & Differentiation

Abstract

Exposure of keratinocytes (KC) to ultraviolet (UV) radiation results in the initiation of apoptosis, a protective mechanism that eliminates cells harboring irreparable DNA damage. Hence, a manipulation of UV-induced apoptosis may significantly influence photocarcinogenesis. We have discovered that the aryl hydrocarbon receptor (AHR), a key regulator of drug metabolism and an UVB-sensitive transcription factor, serves an anti-apoptotic function in UVB-irradiated human KC. Chemical and shRNA-mediated inhibition of AHR signaling sensitized KC to UVB-induced apoptosis by decreasing the expression of E2F1 and its target gene checkpoint kinase 1 (CHK1). The decreased expression of these cell-cycle regulators was due to an enhanced expression of p27(KIP1) and an associated decrease in phosphorylation of both cyclin-dependent kinase 2 and its substrate molecule retinoblastoma protein. The subsequent inhibition of E2F1 autoregulation and downstream CHK1 expression resulted in an enhanced susceptibility of damaged cells to undergo apoptosis. Accordingly, ectopic overexpression of either E2F1 or CHK1 in AHR-knockdown KC attenuated the observed sensitization to UVB-induced apoptosis. Using an AHR-knockout SKH-1 hairless mouse model, we next demonstrated the physiological relevance of the anti-apoptotic function of AHR. In contrast to their AHR-proficient littermates, the constitutive expression of E2F1 and CHK1 was significantly reduced in the skin of AHR-knockout mice. Accordingly, a single exposure of the animals to UVB resulted in an enhanced cleavage of caspase-3 in the skin of AHR-knockout mice. These results identify for the first time the AHR-E2F1-CHK1 axis as a novel anti-apoptotic pathway in KC, which may represent a suitable target for chemoprevention of non-melanoma skin cancer.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1038/cdd.2013.102

Cites

64 of 64 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • β-actin (ACTB) was used as a control housekeeping gene because its gene expression is not affected by AHR ligation.

    “We used β-actin (ACTB) as a control housekeeping gene, because its gene expression is not affected by AHR ligation [18,35].”

    From Antioxidant Artemisia princeps Extract Enhances the Expression of Filaggrin and Loricrin via the AHR/OVOL1 Pathway (2017) · cites this paper as [35]

    The Quantitative real-time PCR subsection of Materials and Methods (page unavailable) says gene expression was normalized to β-actin, supporting its use as a control. Our copy does not state or demonstrate that β-actin expression is unaffected by AHR ligation; the reported lack of response to an AHR agonist concerns E2F1 promoter activity, not β-actin. (LLM, conf=0.83)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. Jacobsen BK, Bjelke E, Kvale G, Heuch I. Coffee drinking, mortality, and cancer incidence: results from a Norwegian prospective study. J Natl Cancer Inst. 1986;76:823–831. [PubMed] [Google Scholar]

Cited by

Sorted by citations

Authors
Frauenstein, K., Sydlik, U., Tigges, J., Majora, M., Wiek, C., Hanenberg, H., Abel, J., Esser, C., Fritsche, E., Krutmann, J., & Haarmann-Stemmann, T.
Affiliations
  • Leibniz Institute of Environmental Medicine (DE)
  • Heinrich Heine University Düsseldorf (DE)
Venue
Cell Death & Differentiation
Published
2013-08-02
Volume
20
Issue
10
Pages
1425-1434
ISSN
  • 1350-9047 (ISSN-L)
  • 1476-5403
OpenAlex
W1979802104
Cited by
56
References
63
Citations by year
2026: 4 · 2025: 2 · 2024: 4 · 2023: 2 · 2022: 5 · 2021: 4 · 2020: 3 · 2019: 3 · 2018: 7 · 2017: 5 · 2016: 5 · 2015: 8 · 2014: 4
FWCI
6.65
Type
journal article
Language
en
Open access
Locations
  • Cell Death and Differentiation (publishedVersion)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • Deutsche Forschungsgemeinschaft (SPP 1230)
  • Bundesministerium für Bildung und Forschung
  • Symrise
Topics
  • Health Sciences › Medicine › Dermatology › Skin Protection and Aging
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Cell death mechanisms and regulation
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › DNA Repair Mechanisms
Keywords
aryl hydrocarbon receptor, E2F1, Chk1, keratinocytes, UVB-induced apoptosis, anti-apoptotic pathways, p27, CDK2, retinoblastoma protein, caspase-3 cleavage, photocarcinogenesis, AhR knockout mice, shRNA knockdown
MeSH terms
Checkpoint Kinase 1, Animals, Humans, Male, Protein Kinases, Transfection, Signal Transduction, Keratinocytes, Apoptosis, Receptors, Aryl Hydrocarbon, Mice, Knockout, E2F1 Transcription Factor, Mice, Basic Helix-Loop-Helix Transcription Factors, Basic Helix-Loop-Helix Proteins

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review