[Expression and Clinical Significance of MiR-215 and KDM1B in Patients with Diffuse Large B Cell Lymphoma].

AbstractObjective:To investigate the expression of miR-215 and KDM1B in DLBCL patients, and to analysis its clinical significance. METHODS Fifty patients with DLBCL treated in our hospital were selected as DLBCL group, and 30 cases of reactive proliferative lymphadenitis（RPL） were selected as controls. RQ-PCR was used to detect the expression level of miR-215, and immunohistochemistry was used to detect the expression of KDM1B protein. The expression of miR-215 and KDM1B in patients with different clinical characteristics and the survival rate of patients with different expression of miR-215 and KDM1B was compared. miR-215 mimics was transfected into SU-DHL-4 cells. Cell proliferation was detected by CCK-8. Cell apoptosis was measured by flow cytometry. The expression of KDM1B protein was detected by Western blot. RESULTS The expression of miR-215 in DLBCL patients was significantly lower than that in control group, and the positive expression of KDM1B protein was higher, the difference was statistically significant(P<0.01). Spearman rank correlation analysis showed that the expression of miR-215 negatively correlated with KDM1B (r=-0.751，P<0.05). There was significant correlation of miR-215, KDM1B expression with symptoms of B，Serum level of LDH, International Prognostic Index(IPI), Ann Arbor stage,Tumor size, respectively in patients(P<0.05). Kaplan-Meier showed that 5-year overall survival rate of patients with high miR-215 expression was significantly longer than that with low miR-215 expression (P=0.013). The 5-year survival rate of the patients with high positive KDM1B expression was significantly lower than that with low positive expression(P=0.024). KDM1B protein was suppressed by the transfection of miR-215 mimics for 72 h, the cell proliferation rate in miR-215 mimics group was significantly lower than that in control group and NC mimics group (P<0.05), but cell apoptotic rate of miR-215 mimics were significantly higher(P<0.05). The expression of KDM1B protein was significantly lower than that in control and NC group(P<0.05). CONCLUSION There are low expression of miR-215 and high expression of KDM1B protein in patients with DLBCL， suggesting that they may be the diagnostic and prognostic indicators of DLBCL. miR-215 can directly target KDM1B to inhibit cell growth and induce apoptosis.