tailieunhanh - Báo cáo y học: " High cell density and latent membrane protein 1 expression induce cleavage of the mixed lineage leukemia gene at 11q23 in nasopharyngeal carcinoma cell line"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học quốc tế cung cấp cho các bạn kiến thức về ngành y đề tài: High cell density and latent membrane protein 1 expression induce cleavage of the mixed lineage leukemia gene at 11q23 in nasopharyngeal carcinoma cell line | Yee and Sim Journal of Biomedical Science 2010 17 77 http content 17 1 77 The cost of publication in Journal of Biomedical Science Is borne by the National Science Council Taiwan JOURNAL OF BIOMEDICAL SCIENCE RESEARCH Open Access High cell density and latent membrane protein 1 expression induce cleavage of the mixed lineage leukemia gene at 11q23 in nasopharyngeal carcinoma cell line Peter Han-Chung Yee Sai-Peng Sim Abstract Background Nasopharyngeal carcinoma NPC is commonly found in Southern China and South East Asia. Epstein-Barr virus EBV infection is well associated with NPC and has been implicated in its pathogenesis. Moreover various chromosome rearrangements were reported in NPC. However the underlying mechanism of chromosome rearrangement remains unclear. Furthermore the relationship between EBV and chromosome rearrangement with respect to the pathogenesis of NPC has not been established. We hypothesize that during virus- or stress-induced apoptosis chromosomes are initially cleaved at the base of the chromatin loop domain structure. Upon DNA repair cell may survive with rearranged chromosomes. Methods In this study cells were seeded at various densities to induce apoptosis. Genomic DNA extracted was processed for Southern hybridization. In order to investigate the role of EBV especially the latent membrane protein 1 LMP1 LMP1 gene was overexpressed in NPC cells and chromosome breaks were analyzed by inverse polymerase chain IPCR reaction. Results Southern analysis revealed that high cell density resulted in cleavage of the mixed lineage leukemia MLL gene within the breakpoint cluster region bcr . This high cell density-induced cleavage was significantly reduced by caspase inhibitor Z-DEVD-FMK. Similarly IPCR analysis showed that LMP1 expression enhanced cleavage of the MLL bcr. Breakpoint analysis revealed that these breaks occurred within the matrix attachment region scaffold attachment region MAR SAR . Conclusions Since MLL .