弥漫大B细胞性淋巴瘤中t(14;18)易位及BCL2表达的意义

  目的  探讨弥漫大B细胞性淋巴瘤(DLBCL)中t(14;18)易位及BCL2表达的意义。  方法  用石蜡包埋组织免疫组织化学法检测142例淋巴结、胃肠道和咽淋巴环等不同器官或部位发生的DLBCL中CD10、BCL6、MUM1和BCL2的抗原表达, 按免疫表型将DLBCL分成GCB-DLBCL和非GCB-DLBCL两个亚型; 聚合酶链反应(PCR)扩增75例淋巴结结内DLBCL新鲜组织中由t(14;18)易位所形成的MBR/JH和lnfr/JH重组基因。  结果  142例DLBCL中, 75例(52.8%)表达BCL2。分型为GCB-DLBCL的51例中, 18例(35.3%)表达BCL2;分型为非GCB-DLBCL的91例中, 57例(62.6%)表达BCL2, 两者阳性率比较有显著性差异(P=0.002)。同时, BCL2的表达阳性率按不同器官或部位发生的DLBCL作比较, 结果也存在显著性差异(P=0.01)。18.7%的淋巴结结内DLBCL中有t(14;18)易位, 阳性病例主要见于GCB-DLBCL之中。  结论  t(14;18)易位是GCB—DLBCL亚型的遗传学特征, BCL2表达在不同亚型和不同器官或部位发生的DLBCL中有显著性差异。 

Significance of t(14;18) Translocation and BCL2 Expression in Diffuse Large B-cell Lymphoma

  Objective  This study aims to explore the significance oft (14; 18) translocation and BCL2 expression in diffuse large B-cell lymphoma (DLBCL).  Methods  Data from 142 cases with DLBCL in various organs and sites were retrieved from the file. The expression of CD 10, Bcl6, MUM 1, and BCL2 antigen was detected in paraffin-embedded tissues using immunohistoehemical techniques. Germinal cell-B (GCB)-DLBCL and non-GCB-DLBCL subtypes were then identified through immunophenotyping. The occurrence of t (14; 18) translocation, manifested as a MBR/JH or mcr/JH gene rearrangement, in 75 lymph node DLBCL cases was analyzed by polymerase chain reaction using fresh samples.  Results  BCL2 expression was present in 52.8% (75/142) of the cases. Among the 51 total cases with a GCB subtype, 18 presented BCL2 expression (35.3%), whereas in 91 of the 103 cases with a non-GCB subtype, BCL2 was expressed in 57 (62.6%). The positive rate for BCL2 in the two groups differed significantly (P = 0.002). BCL2 expression was also significantly different in patients with DLBCL compared with patients with lesions in other organs/sites (P = 0.01). The t (14; 18) translocation was seen in the lymph nodes of 18.7% of the DLBCL cases, with positive cases mainly seen in those with GCB-DLBCL.  Conclusion  The t (14; 18) translocation is the genetic feature of GCB-DLBCL. BCL2 expression shows heterogeneity in DLBCL of different subtypes and in different organs sites.