Expression and significance of leptin receptor and phosphorylation of signal transducer and activator of transcription 3 in diffuse large B-cell lymphoma

Abstract

Objective To investigate the expression and clinical significance of leptin receptor (OBR) and phosphorylation of signal transducer and activator of transcription (p-STAT3) in patients with diffuse large B-cell lymphoma (DLBCL).Methods Immunohistochemical analysis was used to detect the expression of OBR and p-STAT3 in 80 patients with DLBCL and 10 patients with reactive lymphoid hyperplasia (RLH).Using a panel of immunohistochemical markers (CD10,bcl-6 and Mum-1),all cases of DLBCL were further divided into two groups,GCB (germinal center B-cell-like) or non-GCB.Results Immunohistochemistry revealed high expression of OBR and p-STAT3 in 45.0 ％ (36/80) and 28.8 ％ (23/80) cases of DLBCL,respectively,and minimal straining in 100.0 ％ (10/10) cases of RLH (P ＜ 0.05).Compared with GCB group (8.7 ％,2/23),non-GCB group had higher p-STAT3 high expression rate (36.8 ％,21/57) (P ＜ 0.05).There was no significant difference in the expression of OBR between these two groups.Compared with clinical stage Ⅰ-Ⅱ [46.2 ％ (18/39) and 25.6 ％ (10/39)],stage Ⅲ-Ⅳ had higher OBR and p-STAT3 high expression rate [61.9 ％ (13/21) and 38.1％ (8/21)] (P ＞ 0.05).The expression of OBR and p-STAT3 were not correlated with age,gender,extranodal infiltrations,LDH level,B-symptoms and IPI(international prognostic index)(P ＞ 0.05).The expression of OBR was positively related with that of p-STAT3 in DLBCL patients (r =0.232,P =0.039).Conclusion OBR could stimulate the JAK-STAT signaling pathway and induces the phosphorylation of STAT3.This may be involved in carcinogenesis and prognosis of DLBCL. Key words: Lymphoma, large B-cell, diffuse; Immunophenotyping; Receptors, leptin; STAT3; Immunohistochemistry