Clinical significance and detection of micro RNA ‐21 in serum of patients with diffuse large B ‐cell lymphoma in C hinese population

Background Expression patterns of micro RNA s in serum are involved in potentially non‐invasive biomarkers for various diseases. The purpose of this study is to examine the expression of miR‐21 in serum of patients with diffuse large B ‐cell lymphoma ( DLBCL ) and to validate the significance of miR‐21 in early diagnosis, genotyping, treatment options as well as its prognosis estimates of C hinese DLBCL . Methods miR‐21 expression was detected by fluorescent quantity polymerase chain reaction ( qPCR ) in 9 DLBCL cell lines (OCI‐Ly1, OCI‐Ly3, OCI‐Ly4, OCI‐Ly7, OCI‐Ly8, OCI‐Ly10, OCI‐Ly18, OCI‐Ly19, and HBL), as well as in tumor tissue and serum samples from patients with DLBCL (germinal center B ‐cell‐like ( GCB ) DLBCL 32; activated B ‐cell‐like ( ABC ) DLBCL 30) and 50 healthy subjects. Results Expression of miR‐21 was increased in DLBCL cell lines. Compared with the miR‐21 expression of GCB subgroup ( OCI ‐Ly1, OCI ‐Ly4, OCI ‐Ly7, OCI ‐Ly8, OCI ‐Ly18, OCI ‐Ly19), ABC subgroup ( OCI ‐Ly3, OCI ‐Ly10, and HBL ) has higher expression ( t =  11.18, P  < 0.01). Circulating miR‐21 level in sera from patients with DLBCL was associated with matched tumor tissue ( r 2  = 0.931, P  <   0.0001). Consistent with the in vitro , miR‐21 expression levels in serum of patients with DLBCL [21.38(10.26–45.21)] were higher than those in serum of control cases [1.87(1.05–3.97); U  =   168, P  =   0.000]. Moreover, miR‐21 expression levels in serum of patients with subgroup ABC [28.68(14.92~98.44)] were higher than that of patients with subgroup GCB [18.3(7.32~33.46); U  =   336, P  =   0.043]. miR‐21 expression in serum of DLBCL with stage I and II were higher than those in stage III and IV ( U  =   62, P  =   0.013 in GCB type; U  =   53, P  =   0.014 in ABC type). Compared with relapse‐free survival in patients with DLBCL , high expression of miR‐21 was associated with well prognosis ( U  =   259, P  =   0.035). Conclusion miR‐21 expressed in the serum of patients with DLBCL from C hinese was associated with clinical stage, molecular subgroup, and prognosis estimates. miR‐21 may be served as a biomarker in early diagnosis, genotyping, treatment options, and prognosis estimating of C hinese DLBCL .