Assuntos
Neoplasias da Medula Óssea/patologia , Neoplasias da Coroide/patologia , Linfoma de Zona Marginal Tipo Células B/patologia , Neoplasias dos Seios Paranasais/patologia , Seio Esfenoidal/patologia , Anticorpos Monoclonais Murinos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Medula Óssea/tratamento farmacológico , Neoplasias da Medula Óssea/metabolismo , Neoplasias da Coroide/tratamento farmacológico , Neoplasias da Coroide/metabolismo , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Humanos , Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Linfoma de Zona Marginal Tipo Células B/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias dos Seios Paranasais/tratamento farmacológico , Neoplasias dos Seios Paranasais/metabolismo , Tomografia por Emissão de Pósitrons , Prednisolona/uso terapêutico , Descolamento Retiniano/diagnóstico por imagem , Descolamento Retiniano/tratamento farmacológico , Descolamento Retiniano/patologia , Rituximab , Tomografia Computadorizada por Raios X , Ultrassonografia , Vincristina/uso terapêuticoRESUMO
PURPOSE: To evaluate whether RNA interference against apoptosis signal-regulating kinase-1 (ASK-1), a gene involved in stress-induced apoptosis, inhibits photoreceptor death in retinal degeneration 1 (rd1) mice. METHODS: Retinal explants from rd1 mice were subjected to organ cultures on postnatal day 9 (P9). Short interfering RNA (siRNA) for ASK-1 was transfected into cultured retinas at the onset of experiments. Real-time PCR was performed to evaluate the natural expression of ASK-1 mRNA and its inhibition with siRNA. Retinal explants were fixed at P13 and P16, and consecutive cryosections were prepared. Histological and immunohistochemical examinations including TUNEL assays were performed. RESULTS: In preliminary experiments, the incorporation of fluorescent siRNA was found in cells in the outer nuclear and inner nuclear layers on the day following transfection. The expression of ASK-1 mRNA increased with time, which was suppressed more than 70% by siRNA. ASK-1 immunopositive cells were found mostly in the outer nuclear layers, and the number of immunopositive cells was remarkably reduced in retinas treated with siRNA for ASK-1 compared to untreated controls. The thickness of outer nuclear layers of control retinas decreased with time, while the thickness of siRNA transfected retinas was significantly preserved compared to control at P16 (p=0.0021). In TUNEL assays, siRNA for ASK-1 significantly decreased TUNEL-positive cells (49% and 42% of controls at P13 and 16, p=0.039 and 0.0028, respectively). CONCLUSIONS: RNA interference against ASK-1 may provide a benefit by inhibiting photoreceptor apoptosis in rd1 mice.
