Pittaluga S, Ayoubi T A, Wlodarska I, Stul M, Cassiman J J, Mecucci C, Van Den Berghe H, Van De Ven W J, De Wolf-Peeters C
Department of Pathology, K.U. Leuven, Belgium.
J Pathol. 1996 Jun;179(2):145-50. doi: 10.1002/(SICI)1096-9896(199606)179:2<145::AID-PATH565>3.0.CO;2-1.
Chromosomal abnormalities involving 3q27 have recently been associated with diffuse large B-cell lymphomas and, less frequently, with follicular lymphomas. Molecular studies have led to the identification of the BCL-6/LAZ-3 gene, located at 3q27 and coding for a putative zinc-finger protein that might act as a transcriptional regulator during cell differentiation and development. Rearrangement of BCL-6 results in truncation of the gene in its 5' portion, leaving the protein intact; a resultant deregulation of its expression has been hypothesized. In order to test this hypothesis, the expression of BCL-6 protein was investigated in human reactive lymphoid tissue and compared with a group of non-Hodgkin's lymphomas (NHLs) with or without 3q27 anomalies and/or BCL-6 gene rearrangement. BCL-6 protein is consistently expressed in reactive lymphoid tissues, where it is restricted to the follicle centre. The protein is also widely expressed in NHL: all follicular lymphomas tested showed a pattern of expression similar to the reactive B follicle, independently of the presence of BCL-6 gene rearrangement and/or 3q27 anomalies. In the diffuse large B-cell lymphomas, there was more variation in BCL-6 expression, but a correlation with 3q27 anomalies and/or BCL-6 rearrangement was not found. Deregulation of the BCL-6 gene did not result in an aberrant tissue expression as detected by immunohistochemistry.
涉及3q27的染色体异常最近被认为与弥漫性大B细胞淋巴瘤有关，较少情况下与滤泡性淋巴瘤有关。分子研究已鉴定出位于3q27的BCL-6/LAZ-3基因，该基因编码一种假定的锌指蛋白，可能在细胞分化和发育过程中作为转录调节因子发挥作用。BCL-6的重排导致该基因在其5'部分被截断，而蛋白质保持完整；由此推测其表达失调。为了验证这一假设，研究了BCL-6蛋白在人类反应性淋巴组织中的表达，并与一组有或没有3q27异常和/或BCL-6基因重排的非霍奇金淋巴瘤（NHL）进行了比较。BCL-6蛋白在反应性淋巴组织中持续表达，且仅限于滤泡中心。该蛋白在NHL中也广泛表达：所有检测的滤泡性淋巴瘤均显示出与反应性B滤泡相似的表达模式，与BCL-6基因重排和/或3q27异常的存在无关。在弥漫性大B细胞淋巴瘤中，BCL-6表达的变化更大，但未发现与3q27异常和/或BCL-6重排存在相关性。通过免疫组织化学检测，BCL-6基因的失调并未导致异常的组织表达。
