RESUMO
B-cell lymphoma/leukemia 10 (BCL10) is an apoptotic regulatory protein related to advanced TNM stage and disease recurrence in oral squamous cell carcinoma (OSCC). However, the regulatory mechanism of BCL10 in OSCC progression is still unknown. Here, we showed that knockdown of endogenous BCL10 could significantly reduce cell migration and invasion abilities, retard cell proliferation by G0/G1 phase accumulation and inhibit tumorigenicity in vivo. In molecular level, we identified S100P as a crucial downstream effector of BCL10-inhibited OSCC progression by high-throughput microarray analysis. S100P messenger RNA and protein expression levels were significantly diminished in silenced-BCL10 clones, and transfected S100P expression plasmids restored migration, invasion, proliferation abilities and tumorigenicity in shBCL10 transfectants. Furthermore, we provided evidence that BCL10 regulated S100P expression through signal transducers and activators of transcription 1 (STAT1) and activating transcription factor 4 (ATF4). Knockdown of BCL10 decreased S100P promoter activity, but showed no effect in truncated STAT1/ATF4 S100P promoter. In addition, we also found that the P50/P65 signaling pathway was involved in BCL10-enhanced OSCC progression. Restored S100P in silenced-BCL10 clones could markedly reverse P65 activation via outside-in signaling. Taken together, we discovered a novel axis of BCL10-regulated OSCC progression via STAT1/ATF4/S100P/P65 signaling, which could predict the prognosis of OSCC and will be beneficial for developing therapeutic strategy against advanced OSCC.
Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Neoplasias Bucais/metabolismo , Proteínas de Neoplasias/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais , Fator 4 Ativador da Transcrição/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteína 10 de Linfoma CCL de Células B , Sítios de Ligação , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Camundongos , Neoplasias Bucais/genética , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Prognóstico , Ligação Proteica , Ativação TranscricionalRESUMO
Development of the eye is morphologically similar among vertebrates, indicating that the underlying mechanism regulating the process may have been highly conserved during evolution. Herein we analyzed the promoter of the human betaB1-crytallin gene in zebrafish by transgenic experiments. To delineate the evolutionarily conserved regulatory elements, we performed serial deletion assays in the promoter region. The results demonstrated that the -90/+61-bp upstream proximal promoter region is sufficient to confer lens-tissue specificity to the human betaB1-crystallin gene in transgenic zebrafish. Through phylogenetic sequence comparisons and an electrophoretic mobility shift assay (EMSA), a highly conserved cis-element of a six-base pair sequence TG(A/C)TGA, the consensus sequence for the Maf protein binding site, within the proximal promoter region was revealed. Further, a site-mutational assay showed that this element is crucial for promoter activity. These data suggest that the fundamental transcriptional regulatory mechanism of the betaB1-crystallin gene has been well conserved between humans and zebrafish, and plausibly among all vertebrates, during evolution.
Assuntos
Regiões Promotoras Genéticas/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Cadeia B de beta-Cristalina/genética , Animais , Animais Geneticamente Modificados , Sequência de Bases , Sítios de Ligação , Sequência Conservada , Humanos , Dados de Sequência Molecular , Filogenia , Proteínas Proto-Oncogênicas c-maf/genética , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica/genética , Peixe-Zebra/embriologiaRESUMO
BACKGROUND: The major alkaloid in the betel nut, arecoline, has been reported to be potent in inducing developmentally toxic effects by generally lowering the embryo weight and retarding development of the embryo. This study examined the adverse effects of arecoline and tried to unravel the mechanism through the tools of molecular biology. METHODS: Arecoline was administered to zebrafish embryos by incubation at concentrations ranging from 0.01-0.04% (wt/vol) and lethality and morphological changes were recorded. The expression of genes was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and whole-mount in situ hybridization. In addition, the protective effects of several antioxidants were tested. RESULTS: The survival rate of treated embryos during a three-day incubation significantly declined as the arecoline concentration increased. Treated embryos showed general growth retardation and lower rate of heartbeat. When examined at the 24-hr stage, the relative amounts of transcripts of p53, p21, and cyclin D1, and the spatial expression patterns of these genes in treated groups, were comparable to those of the untreated early stages of embryos. Finally, the addition of glutathione (GSH) or its precursor, N-acetyl-L-cysteine (NAC), ameliorated the developmental retardation of embryos by arecoline. CONCLUSIONS: Arecoline-treated embryos exhibited general developmental retardation in a dose-dependent manner. Our results from RT-PCR, in situ hybridization, and antioxidant-protection experiments indicate that the mechanism underlying growth retardation by arecoline in embryos is predominantly due to a general cytotoxic effect induced by depletion of intracellular thiols.
