Transcriptional signature of epidermal keratinocytes subjected to in vitro scratch wounding reveals selective roles for ERK1/2, p38, and phosphatidylinositol 3-kinase signaling pathways.
Covering denuded dermal surfaces after injury requires migration, proliferation, and differentiation of skin keratinocytes. To clarify the major traits controlling these intermingled biological events, we surveyed the genomic modifications occurring during the course of a scratch wound closure of cultured human keratinocytes. Using a DNA microarray approach, we report the identification of 161 new markers of epidermal repair. Expression data, combined with functional analysis performed with specific inhibitors of ERK, p38(MAPK) and phosphatidylinositol 3-kinase (PI3K), demonstrate that kinase pathways exert very selective functions by precisely controlling the expression of specific genes. Inhibition of the ERK pathway totally blocks the wound closure and inactivates many early transcription factors and EGF-type growth factors. p38(MAPK) inhibition only delays "healing," probably in line with the control of genes involved in the propagation of injury-initiated signaling. In contrast, PI3K inhibition accelerates the scratch closure and potentiates the scratch-dependent stimulation of three genes related to epithelial cell transformation, namely HAS3, HBEGF, and ETS1. Our results define in vitro human keratinocyte wound closure as a repair process resulting from a fine balance between positive signals controlled by ERK and p38(MAPK) and negative ones triggered by PI3K. The perturbation of any of these pathways might lead to dysfunction in the healing process, similar to those observed in pathological wounding phenotypes, such as hypertrophic scars or keloids.
Fitsialos
Giorgos
G
INSERM, U634, 28 Avenue de Valombrose, F-06107 Nice cedex 2, France.
Chassot
Anne-Amandine
AA
Turchi
Laurent
L
Dayem
Manal A
MA
LeBrigand
Kevin
K
Moreilhon
Chimène
C
Meneguzzi
Guerrino
G
Buscà
Roser
R
Mari
Bernard
B
Barbry
Pascal
P
Ponzio
Gilles
G
D015415:Biomarkers / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics; D002465:Cell Movement / Q000187:drug effects / Q000235:genetics; D020405:Dermis / Q000201:enzymology* / Q000293:injuries* / Q000473:pathology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects / Q000235:genetics; D015894:Genome, Human; D006801:Humans; D007627:Keloid / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D015603:Keratinocytes / Q000201:enzymology* / Q000473:pathology; D020935:MAP Kinase Signaling System / Q000235:genetics; D019950:Mitogen-Activated Protein Kinase 1 / Q000235:genetics / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000378:metabolism*; D014945:Wound Healing / Q000187:drug effects / Q000235:genetics
D015415:Biomarkers; D004791:Enzyme Inhibitors; D019869:Phosphatidylinositol 3-Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3