RESUMO
It has been suggested that epithelial cyclooxygenase-2 (COX-2) promotes oral carcinogenesis and carcinoma malignancy through increased prostaglandin E(2) (PGE(2)) production. Although oral squamous cell carcinomas (OSCC) often express COX-2, they may also produce PGE(2) in a COX-1-dependent manner. We used 6 isolated cell lines to investigate which COX isoforms OSCC may use for PGE(2) production. COX-1 and -2 expression patterns divided the 6 OSCC cell lines into 3 distinct groups: both COX isoforms low, only COX-1 high, or both COX isoforms high. Multicolor immunohistofluorescence staining confirmed the COX-expression profiles in organotypic 3D cultures and the COX-2 dominance in OSCC tumors. Epidermal growth factor (EGF) stimulation induced COX-2 (but not COX-1) expression and increased PGE(2) production, which was attenuated by COX-2 (but not COX-1) specific inhibition or siRNA-mediated COX-2 gene knockdown. Thus, PGE(2) production in OSCC cell lines was COX-2-dependent.
Assuntos
Carcinoma de Células Escamosas/metabolismo , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/biossíntese , Neoplasias Bucais/metabolismo , Idoso , Linhagem Celular Tumoral , Ciclo-Oxigenase 1/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Dinoprostona/genética , Fator de Crescimento Epidérmico/farmacologia , Feminino , Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Oxirredutases Intramoleculares/biossíntese , Isoenzimas/biossíntese , Masculino , Pessoa de Meia-Idade , Prostaglandina-E Sintases , RNA Interferente Pequeno/farmacologiaRESUMO
We report the screening of thirty-one YACs with a number of markers using polymerase chain reaction (PCR) to construct a physical map of part of human chromosome 17q21.3-q22. A contig of YACs covering about 4 Mb was constructed around the TCF11 gene at 68 cM from the most telomeric marker on the p arm, localizing TCF11 telomeric to genetic marker D17S1827. Both human and mouse P1-derived artificial chromosomes (PACs) containing TCF11 were isolated and characterized. The human heterochromatin protein 1 gene, HP1Hsbeta, and its homologue in mouse, MoMOD1, were identified centromeric to TCF11.
