[Expression of NAMPT in Patients with Multiple Myeloma and Its Correlation with Clinical Manifestation]

To analyze the expression level of nicotinamide phosphoribosyltransferase (NAMPT ) in bone marrow of multiple myeloma (MM) patients and its correlation with clinicopathological features, clinical efficacy and prognosis.

RT-qPCR and Western blot were used to detect the expression of NAMPT mRNA and protein in bone marrow mononuclear cells from 85 newly diagnosed MM patients (including 17 relapsed MM patients) and 15 healthy donors, and explore the correlation of the expression of NAMPT gene with clinicopathological features and efficacy. Kaplan-Meier method was used to analyze the effects of NAMPT on progression-free survival (PFS) and overall survival (OS), and univariate and multivariate survival analysis were performed.

The median expression level of NAMPT mRNA in bone marrow of newly diagnosed and relapsed MM patients was significantly higher than that of healthy donors (P <0.001). The expression of NAMPT mRNA in relapsed MM patients was significantly higher than that in newly diagnosed MM patients (P <0.001), which was consistent with the expression of NAMPT protein. ISS staging, lactate dehydrogenase and C-reactive protein levels, p53 deletion and the proportion of myeloma cells were increased in high NAMPT expression group compared with low NAMPT expression group (P <0.001). Compared with complete remission group, NAMPT mRNA expression was significantly up-regulated in partial remission group, progression group and relapsed group (P <0.001). The median OS and PFS of patients in high NAMPT expression group was 27.3 and 14.9 months, respectively, which was significantly shorter than 39.1 and 27 months in low NAMPT expression group (P =0.048, P <0.001). Both univariate and multivariate analysis showed that NAMPT expression was correlated with PFS and OS.

The expression level of NAMPT in newly diagnosed and relapsed MM patients is significantly higher than that in normal controls, and its up-regulation is related to the adverse clinical characteristics, efficacy and prognosis of MM patients. NAMPT is an independent prognostic risk factor of MM.