ebna1 upregulates p53-inhibiting genes in burkitt's lymphoma cell line

Background: suppression of p53 is an important mechanism in epstein-barr virus associate-tumors and described as ebna1-usp7 which is a key axis in p53 suppression. thus, in this study, we aimed to evaluate the function of ebna1 on the expression of p53-inhibiting genes including hdac-1, mdm2, mdm4, sirt-3, and psmd10 and the influence of usp7 inhibition using gne-6776 on p53 at protein/mrna level.methods:  the electroporation method was used to transfect the bl28 cell line with ebna1. cells with stable ebna1 expression were selected by hygromycin b treatment. the expression of seven genes, including psmd10, hdac-1, usp7, mdm2, p53, sirt-3, and mdm4, was evaluated using a real-time pcr assay. for evaluating the effects of usp7 inhibition, the cells were treated with gne-6776; after 24 hours and 4 days, the cells were collected and again expression of interest genes was evaluated.results: mdm2 (p=0.028), mdm4 (p=0.028), usp7 (p=0.028), and hdac1 (p=0.015) all showed significantly higher expression in ebna1-harboring cells compared to control plasmid transfected cells, while p53 mrna expression was only marginally downregulated in ebna1 harboring cells (p=0.685). four-day after treatment, none of the studied genes was significantly changed. also, in the first 24-hour after treatment, mrna expression of p53 was downregulated (p=0.685), but after 4 days it was upregulated (p=0.7) insignificantly.conclusions: it seems that ebna1 could strongly upregulate p53-inhibiting genes including hdac1, mdm2, mdm4, and usp7. moreover, it appears that the effects of usp7 suppression on p53 at protein/mrna level depend on the cell nature; however, further research is needed.