Abstract: Objective To observe the effect of pseudolaric acid B(PAB) on the proliferation and apoptosis of human diffuse large B-cell lymphoma cell line SU-DHL-4 possibly and to explore the potential mechanism through regulating miR-4282. Methods SU-DHL-4 cells were divided into control group, PAB-L group, PAB-M group, PAB-H group; According to liposome method, miR-NC and miR-4282 were transfected into the cells and were marked as miR-NC group, miR-4282 group; The anti-miR-NC, anti-miR-4282 were transfected into the cells,cultured with 20 μmol/L PAB, denoted as (PAB+anti-miR-NC)group and(PAB+anti-miR-4282)group. Cell pro- liferation was detected by CCK8 assay, and cell apoptosis was detected by flow cytometry. The expression of Ki-67,cleaved caspase-3, cleaved caspase-9 protein was detected by Western blot and miR-4282 expression was detected by RT-qPCR. Results Compared with the control group, Ki-67 protein expression in PAB-L group, PAB-M group, and PAB-H group was decreased while miR-4282 expression, and the apoptosis rate, cell inhibition rate, protein expression of cleaved caspase-3, cleaved caspase-9 were increased (P＜0.05). Compared with the miR-NC group, Ki-67 protein expression in miR-4282 group decreased, while miR-4282 expression, the apoptosis rate, cell inhibition rate, protein expression of cleaved caspase-3, cleaved caspase-9 were all increased (P＜0.05). Inhibition of miR-4282 expression reduced the effect of PAB on the proliferation and apoptosis of SU-DHL-4 cells. Conclusions PAB may inhibit the proliferation of human diffuse large B-cell lymphoma cell SU-DHL-4 and promote apoptosis through increased expression of miR-4282.

Key words: pseudolaric acid B, miR-4282, diffuse large B-cell lymphoma, proliferation, apoptosis