Serum miR-21 predicts the prognosis of patients with primary gastrointestinal diffuse large B-cell lymphoma

Abstract

Background: Primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL) lacks specific clinical manifestations and its malignancy renders prognostication and choice of treatment strategy difficult. The aim of this study was to evaluate microRNA (miR)-21 as potential non-invasive biomarkers for prognosis in PGI-DLBCL patients. Methods: Serum miR-21 expression in de novo PGI-DLBCL patients, consecutively enrolled for this study, was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Relative expression was calculated using the comparative Ct method. Statistical significance was determined using the Mann-Whitney rank sum and Fisher’s exact test. Survival analysis was conducted using the Kaplan-Meier method. Results: Compared with healthy controls, serum miR-21 levels were significantly elevated in the PGI-DLBCL patients (n=156). The high expression level of serum miR-21 at diagnosis was associated with worse progression-free survival (PFS) (30 (9–42) vs 42 (12–52) months in high and low miR-21 groups) and overall survival (OS) (35 (15–52) vs 48 (17–61) months in high and low miR-21 groups) and was an independent risk factor for PFS and OS (hazard ratios 4.345 and 3.311, respectively). Furthermore, Bcl-2, Bcl-6 and Ki-67 were independently and positively associated with miR-21 expression. Conclusions: Our results suggest that miR-21 is a potential prognostic marker to predict clinical outcomes in PGI-DLBCL patients and a high miR-21 level is associated with poor outcomes.