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

Abstract

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. 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). 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.