Expression Of DC-SIGNR In Non-Hodgkin Lymphoma And Its Clinical Significance

ObjectiveDC-SIGNR, a type II integral membrane protein and a member of the C-typelectins, has been reported to bind various strains of HIV-1, HIV-2, and simianimmunodeficiency virus. Serum DC-SIGNR is not currently available for the detectionof Non-Hodgkin lymphoma (NHL). This study aims to disscuss the relationshipbetween serum DC-SIGNR levels of NHL and clinical data such as gender, age, AnnArbor stage, the levels of Lactate dehydrogenase (LDH) and β2-microglobulin,B-symptoms and histologic subtypes, as well as the expression of DC-SIGNR inlymphatic endothelial cells.MethodsA total of70NHL patients were enrolled in ELISA, and the non-NHL controlgroup was composed of100healthy blood donor volunteers. We assessed theassociations between serum levels of DC-SIGNR in patients and clinical data. Inaddition, we also performed immunohistochemistry analysis in32NHL lymph nodes ortissues and14reactive hyperplasia lymph nodes and normal lymph nodes of tumorpatients as controls.Results(1) The DC-SIGNR levels were significantly lower in NHL patients than in healthycontrols. Serum concentrations of DC-SIGNR ranged from1.066ng/l to9.232ng/l inNHL patients, and from2.138ng/l to13.92ng/l in healthy controls. The median levelsof DC-SIGNR in NHL patients and healthy controls were4.513ng/l and5.815ng/l，respectively. There was a statistical significance between two groups and the P valuewas0.0003.(2) Serum concentrations of DC-SIGNR correlated significantly with age and LDHand β2-microglobulin levels. The median levels of DC-SIGNR in patients of≤60years old and＞60years old were4.874ng/l and4.173ng/l. Serum levels of DC-SIGNR werehigher in patients of≤60years old than in patients＞60years old. Although thedifference was not statistically significant and the P value was0.0504, serum levels ofDC-SIGNR are significantly correlated with age with a Spearman correlation coefficientof-0.31and a P value of0.0077. In addition, Serum β2-microglobulin levels in54of the70patients showed a moderately negative correlation with DC-SIGNR levels with aSpearman correlation coefficient of-0.27and a P value of0.0491. But serum levels ofDC-SIGNR with normal levels of β2-microglobulin showed no significant differencecompared with high levels and P value was0.1355. Next, the data showed a significantnegative correlation between serum DC-SIGNR and LDH levels in65of70patientswith a correlation coefficient of-0.35and a P value of0.0046. Also, serum levels ofDC-SIGNR with normal levels of LDH showed significant difference compared withhigh levels and P value was0.0092.(3) Serum concentrations of DC-SIGNR showed no significant association withgender (males and females), Ann Arbor stage (stageⅠ/Ⅱ, stage Ⅲ and stage Ⅳ),histologic subtypes (B-cell and T-cell), or B-symptoms (with B-symptoms and withoutB-symptoms) and all P values higher than0.05.(4) As in patients with a lower level of serum, DC-SIGNR expression in lymphaticendothelial cells also showed negative immunostaining levels in NHL patients.DC-SIGNR was strongly expressed in reactive hyperplasia lymph nodes and thepositive cells were stained yellow or brown. In DLBCL, DC-SIGNR showed lowerexpression than reactive hyperplasia lymph nodes and the positive cells were stainedpale yellow. Weak DC-SIGNR expression was revealed in SLL and there was almost nopositive cells expressed.ConclusionFor ELISA, low serum levels of DC-SIGNR were detected in patients. Serumconcentrations of DC-SIGNR correlated significantly with age, LDH andβ2-microglobulin levels. However, we found no statistically significant correlationbetween serum DC-SIGNR levels and clinical data such as gender, Ann Arbor stage,B-symptoms and histologic subtypes. Moreover, NHL patients also showed negativeimmunostaining levels than controls.