RESUMO
Minimal change disease (MCD) in association with low-grade extra-nodal marginal zone B-cell lymphoma (MZL) of mucosa-associated lymphoid tissue (MALT) (MALT lymphoma) is a rare clinicopathologic entity. We report a 68-year-old male who presented with nephrotic range proteinuria as the first manifestation of underlying MZL, confirmed with standard set of investigations. Being a steroid non-responder, he was treated with rituximab demonstrating a marked response with resolution of proteinuria. However, he relapsed after 3 months. Upon relapse, a combination of rituximab and bendamustine (R-Benda) was initiated achieving sustained resolution of proteinuria. No additional treatment was administered and the proteinuria has remained in remission for over a year.
Assuntos
Linfoma de Zona Marginal Tipo Células B/diagnóstico , Nefrose Lipoide/diagnóstico , Adenocarcinoma/diagnóstico , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cloridrato de Bendamustina/administração & dosagem , Cloridrato de Bendamustina/uso terapêutico , Neoplasias do Colo/diagnóstico , Diagnóstico Diferencial , Humanos , Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Masculino , Recidiva Local de Neoplasia/patologia , Segunda Neoplasia Primária/diagnóstico , Proteinúria/diagnóstico , Rituximab/administração & dosagem , Rituximab/uso terapêuticoRESUMO
Analysis of in vivo chromatin remodeling at the PHO5 promoter of yeast led to the conclusion that remodeling removes nucleosomes from the promoter by disassembly rather than sliding away from the promoter. The catalytic activities required for nucleosome disassembly remain unknown. Transcriptional activation of the yeast PHO8 gene was found to depend on the chromatin-remodeling complex SWI/SNF, whereas activation of PHO5 was not. Here, we show that PHO8 gene circles formed in vivo lose nucleosomes upon PHO8 induction, indicative of nucleosome removal by disassembly. Our quantitative analysis of expression noise and chromatin-remodeling data indicates that the dynamics of continual nucleosome removal and reformation at the activated promoters of PHO5 and PHO8 are closely similar. In contrast to PHO5, however, activator-stimulated transcription of PHO8 appears to be limited mostly to the acceleration of promoter nucleosome disassembly with little or no acceleration of promoter transitions following nucleosome disassembly, accounting for the markedly lower expression level of PHO8.