Smad7 positively regulates keratinocyte proliferation in psoriasis.
Br J Dermatol
; 177(6): 1633-1643, 2017 12.
Article
em En
| MEDLINE
| ID: mdl-28580633
ABSTRACT
BACKGROUND:
Transforming growth factor (TGF)-ß1 exerts inhibitory effects on keratinocyte proliferation.OBJECTIVES:
To examine whether Smad7, a known inhibitor of TGF-ß1 signalling, is involved in psoriasis-associated keratinocyte hyperproliferation.METHODS:
Smad7 was evaluated in skin sections of patients with psoriasis and healthy controls and in mice with Aldara-induced skin pathology by real-time polymerase chain reaction and immunohistochemistry. To assess whether Smad7 positively regulates in vivo keratinocyte growth, mice treated with Aldara received daily cutaneous administration of Smad7 antisense oligonucleotide (AS). Keratin (K)6 and K16, cell-cycle-associated factors, cell-cycle and cell proliferation were evaluated in HaCaT cells either treated with Smad7 AS or transfected with Smad7 plasmid and in mice given Smad7 AS.RESULTS:
Smad7 was highly expressed in keratinocytes of patients with psoriasis and of mice treated with Aldara. In HaCaT cells, Smad7 knockdown inhibited cell growth, reduced K6 and K16 expression and promoted accumulation of cells in the S-phase of the cell cycle. Smad7-deficient keratinocytes exhibited reduced levels of CDC25A protein, a phosphatase that facilitates progression of cells through the S-phase, and hyperphosphorylation of eukaryotic initiation factor 2 (eIF2)α, a negative regulator of CDC25 protein translation. Consistently, Smad7 overexpression in HaCaT cells was followed by induction of K6 and K16 and increased cell proliferation. Topical application of Smad7 AS to Aldara-treated mice reduced epidermal thickness.CONCLUSIONS:
Our data show that Smad7 is overexpressed in human and murine psoriasis and suggest a key role of this molecule in the control of keratinocyte proliferation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Psoríase
/
Queratinócitos
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Proliferação de Células
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Proteína Smad7
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Fator de Crescimento Transformador beta1
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Br J Dermatol
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Itália