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.