NMF Identifies two clusters of DLBCL patients with distinct miRNA and outcome profiles. We performed non-negative matrix factorization (NMF) clustering on 83 R-CHOP treated DLBCL patient samples, using the miRNA expression obtained from miRNA-seq data. (a) NMF yielded two clusters of patients (see Additional file 9: Figure S4) that had distinct differences in their outcomes. Patients in cluster 1 are indicated by dark gray bars, while patients in cluster 2 are indicated by light gray bars. Below the consensus matrix is a heatmap showing the expression of miR-148a and miR-21 in each patient. (b) Kaplan-Meier curves showing overall survival and progression-free survival of patients in both clusters. Patients in cluster 1 exhibit inferior outcome compared to those in cluster 2. (c) To identify which miRNAs were characteristic of each cluster, we identified the differentially expressed miRNA between the two clusters. The MA plot shows that miR-21 abundance is increased in cluster 2 patients, while miR-148a abundance is decreased in cluster 1 patients (Wilcoxon test q-value <0.05). (d) Expression patterns of miR-148a and miR-21 are discontinuous. miRNA expression in DLBCL patient samples is indicated with black squares, while expression in centroblast samples is indicated with orange diamonds.