Borovecki Ana, Korac Petra, Ventura Roland A, Perisa Marija Milkovic, Banham Alison H, Dominis Mara
Department of Clinical Pathology and Cytology, Merkur University Hospital, Zagreb, Croatia.
Pathol Int. 2007 Jan;57(1):47-51. doi: 10.1111/j.1440-1827.2007.02056.x.
In view of the certain anatomic site-dependent frequency of chromosomal translocations involved in extranodal marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) pathogenesis, 17 salivary gland MALT lymphoma cases were analyzed for MALT1 and FOXP1 translocations. B cell CLL/lymphoma 10 (BCL10) and forkhead box PA (FOXP1) protein expression were studied by immunohistochemistry and translocations identified using fluorescence in situ hybridization (FISH)-specific probes FOXP1, t(11;18)(q21;q21)/API2-MALT1 and t(14;18)(q32;q21)/IgH-MALT1. None of the 11 analyzed cases showed FOXP1 rearrangement or amplification. The t(11;18) was present in five of 13 cases and the t(14;18) in three of 13 cases. MALT1 translocations were mostly mutually exclusive except in a single case. FOXP1 protein expression showed differences in the proportion of tumor cells with nuclear expression but not in their intensity, with the exception of one case where very intense nuclear staining was noted. BCL10 nuclear expression was present in four of 17 cases, two of which lacked t(11;18). Our results suggest that MALT1-specific translocations and FOXP1 rearrangements are not commonly involved in pathogenesis. A case with strong FOXP1 protein expression indicates the possibility that the upregulation of FOXP1 expression is significant in a small subset of salivary gland MALT lymphomas. Also a single case in which both MALT1 translocations were present indicates that these are not always mutually exclusive.
鉴于黏膜相关淋巴组织结外边缘区B细胞淋巴瘤（MALT淋巴瘤）发病机制中涉及的某些染色体易位存在解剖部位依赖性频率，对17例涎腺MALT淋巴瘤病例进行了MALT1和FOXP1易位分析。通过免疫组织化学研究B细胞慢性淋巴细胞白血病/淋巴瘤10（BCL10）和叉头框PA（FOXP1）蛋白表达，并使用荧光原位杂交（FISH）特异性探针FOXP1、t(11;18)(q21;q21)/API2-MALT1和t(14;18)(q32;q21)/IgH-MALT1鉴定易位。11例分析病例均未显示FOXP1重排或扩增。13例中有5例存在t(11;18)，13例中有3例存在t(14;18)。MALT1易位大多相互排斥，但有1例除外。FOXP1蛋白表达在核表达的肿瘤细胞比例上存在差异，但强度无差异，只有1例观察到非常强烈的核染色。17例中有4例存在BCL10核表达，其中2例缺乏t(11;18)。我们的结果表明，MALT1特异性易位和FOXP1重排通常不参与发病机制。1例FOXP1蛋白表达强烈的病例表明，FOXP1表达上调在一小部分涎腺MALT淋巴瘤中可能具有重要意义。同样有一例同时存在两种MALT1易位，表明它们并非总是相互排斥。
