Abstract: Objective To investigate the differential expression pattern of hsa-miR-9 between EBV-positive and -negative Burkitt
lymphoma cell lines and its association with BCL-6. Methods The expression of hsa-miR9 and BCL-6 mRNAs in EBV+ Raji and
EBV-Ramous cells in mRNA levels were detected using fluorescence quantitative PCR (QRT-PCR). The two cells lines were
transiently transfected with hsa-mir9-inhibitor and hsa-mir9-minicsvia Oligofectamine 2000, and the changes in BCL6
expressions was detected using QRT-PCR and Western blotting. Annexin V/PI staining was used to analyze the apoptosis and
morphological changes of the transfected cells. Results The expression of Hsa-miR9 and BCL-6 was significantly higher in
EBV+ Raji cells than EBV- Ramous cells (P<0.01). BCL-6 mRNA and protein expression was reduced in EBV+ Raji cells after
transfection with hsa-miR9-inhibitor but up-regulated in EBV-Ramous cells transfected with hsa-miR9-minics. Flow cytometry
revealed a significantly decreased apoptosis rate in EBV+ Raji cells transfected with hsa-miR9-inhibitor but an increased rate in
EBV- Ramous cells transfected with hsa-miR9-minics, and the results were confirmed by microscopic observations. Conclusion
Hsa-miR9 positively regulate the expression of BCL-6 and apoptosis of EBV+ Raji cells and EBV- Ramous cells.