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Mutation analysis of the rearranged immunoglobulin heavy chain genes of marginal zone cell lymphomas indicates an origin from different marginal zone B lymphocyte subsets.

Marginal zone cell lymphoma is a recently described entity among the non-Hodgkin's lymphomas. It likely originates from the marginal zone B cells in the spleen and equivalent cells in the lymph node and extranodal tissues. Recent evidence indicates that marginal zone B cells are functionally heterogeneous and may differ with respect to the pattern of somatic hypermutation in their Ig variable genes. To test whether marginal zone lymphomas may originate from different subsets of marginal zone B cells, we performed a sequence and mutation analysis of the rearranged Ig heavy chain (IgH) variable genes (VH) of a series of 14 cases of marginal zone lymphoma, occurring in the spleen (4), the lymph node (4), the stomach (2), the orbit (2), the tongue (1), and the skin (1). Our data show that marginal zone cell lymphomas preferentially rearrange the VH4, VH3, and VH1 family genes, without preference for any particular VH gene. Somatic mutations are present in 13 cases; one case of marginal zone cell lymphoma of the skin showed a germline configuration of the rearranged VH gene. Mutation analysis shows evidence of antigen selection in three cases of marginal zone cell lymphoma, one of the spleen, stomach, and orbit, respectively. No evidence of antigen selection was present in the other cases. These data indicate that marginal zone cell lymphomas may arise from different subsets of marginal zone B cells. In addition, lymphomagenesis may not be triggered by antigen in all cases of marginal zone cell lymphoma.

Aged↗

Oligoclonality of a "composite" gastric diffuse large B-cell lymphoma with areas of marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue type.

We analyzed a case of oligoclonal Helicobacter pylori-associated, primary gastric diffuse large B-cell lymphoma (DLBCL) with areas of extranodal marginal zone B-cell lymphoma (MZBL) of mucosa-associated lymphoid tissue (MALT) type in a 61-year-old male patient. The patient had two separate tumors, in the corpus and in the antrum, each showing two morphologically distinct components (DLBCL and MZBL of MALT type). To determine the clonal relationship between the large- and small-cell components, we microdissected four samples from morphologically distinct tumor components at both tumor sites. PCR analysis revealed rearranged immunoglobulin heavy chain (IgH) genes of different sizes in three of the four microdissected samples. Cloning and sequencing of the PCR products displayed different IgH gene rearrangements in the two small cell components of the antrum and the corpus. A third genuinely differently rearranged IgH gene was found in the large-cell components of both antrum and corpus. Our results suggest that in primary gastric DLBCL with areas of MZBL of MALT type, the small-cell component may comprise more than one tumor clone. Furthermore, the large-cell component may evolve independently from coexisting MZBL.

Amino Acid Sequence↗

Nodal marginal zone B-cell lymphomas may arise from different subsets of marginal zone B lymphocytes.

Nodal marginal zone B-cell lymphoma (MZL) is a rare and not extensively studied entity that accounts for approximately 2% of all non-Hodgkin lymphomas. Complementarity-determining regions 2 and 3 (CDR2, CDR3) of the immunoglobulin heavy-chain variable region (V(H)) genes were amplified by polymerase chain reaction (PCR), cloned, and sequenced in 8 patients with nodal MZL. All showed a potentially functional V(H) rearrangement. The use of V(H) gene families was unbiased and without overrepresentation of any particular V(H) gene or gene family. The presence of somatic V(H) mutations was detected, with a deviation from the closest germ line sequence ranging from 4% to 17% in 6 of 8 patients. In 3 mutations, the replacement-to-silent mutation ratio suggested the presence of an antigen-selected process. Sequencing different subclones of the same cloned PCR products allowed the detection of intraclonal variability in 4 analyzed patients. The observed pattern of V(H) mutations suggested that nodal MZL, formerly deemed a malignancy of memory B cells, may arise from different subsets of marginal zone B cells-the naive B cells that express unmutated V(H) genes-from memory B cells showing somatic mutations without intraclonal variation, and from germinal center B cells defined by their capacity to undergo the somatic hypermutation process. (Blood. 2001;98:781-786)

Adult↗

Constitutive expression of the AP-1 transcription factors c-jun, junD, junB, and c-fos and the marginal zone B-cell transcription factor Notch2 in splenic marginal zone lymphoma.

Splenic marginal zone lymphoma (SMZL) is a lymphoma type of putative marginal zone B-cell origin. No specific genetic alterations have yet been demonstrated in SMZL. Clinically, SMZL is a low-grade B-cell non-Hodgkin lymphoma. However, the presence of p53 mutation, 7q22-7q32 deletion or the absence of somatic hypermutations of immunoglobulin genes has been correlated with a worse prognosis. In this study, we analyzed genome-wide gene expression of 24 cases of SMZL using the microarray technique. The AP-1 transcription factors c-jun, junD, junB, and c-fos as well as Notch2 were found to be specifically up-regulated. These data were confirmed by real-time PCR and immunohistochemical staining of tissue sections. The absence of concordant high expression of the MAP kinases, the signaling cascade leading to AP-1 up-regulation, suggests autoregulation of the AP-1 transcription factors and an important role in SMZL oncogenesis. High expression of Notch2, a transcription factor that induces marginal zone B-cell differentiation, is highly suggestive for a marginal zone B-cell origin of SMZL. In addition, SMZL with the 7q deletion showed high expression of TGF-beta1 and low expression of the DNA helicase XPB, a crucial part of the nucleotide excision repair complex, possibly explaining the more aggressive clinical course of those cases.

Alleles↗

Morphologic and phenotypic changes of the leukemic cells in a case of marginal zone B-cell lymphoma.

A particular case of marginal zone B-cell lymphoma (MZBCL) presenting with leukemic lymphocytes is reported. In the present observation, the leukemic cells not only displayed a remarkable morphological fluctuation but also had an unusual phenotype, changing with time. These phenotypic features, which have been functionaly investigated by in vitro assays, might simply reflect an activation state depending on the microenvironment. Because of its disconcerting similarities with hairy cell leukemia (HCL) and splenic lymphoma with villous lymphocytes (SLVL), this case relaunches the debate about whether close relationships might exist between the splenic marginal zone, SLVL and HCL.

Antigens, CD19↗

Primary cutaneous marginal zone B-cell lymphoma.

Primary cutaneous marginal zone B-cell lymphoma (PCMZL) is included as one of the major types of primary cutaneous B-cell lymphoma in the revised World Health Organization-European Organization for Research and Treatment of Cancer classification. Clinically, PCMZL is an indolent disease and has an excellent prognosis. PCMZL is composed of a polymorphous infiltrate that includes centrocyte-like, monocytoid, and lymphoplasmacytoid lymphocytes and plasma cells. Numerous reactive T cells and lymphoid follicles are commonly associated with the neoplasm. The neoplastic cells express B-cell markers and usually bcl-2 and are negative for CD5, CD10, and bcl-6. Borrelia burgdorferi is a suspected etiologic agent identified in a subset of cases. Although all of these neoplasms presumably are monoclonal, monoclonal IgH rearrangement can only be detected in approximately 75% of cases. Most molecular studies to assess for clonality have used polymerase chain reaction-based methods, and thus this false-negative rate may be attributable to somatic mutation of the IgH variable region genes. Approximately 10% to 20% of PCMZLs have recurrent chromosomal translocations, including the t(14;18)(q32;q21)/IgH-malt1, t(11;18)(q21;q21), and t(3;14)(p14;q32). The t(14;18)(q32;q21) and t(11;18)(q21;q21) have been shown to activate the NF-kappaB pathway.

Adult↗

CD5+ low-grade marginal zone B-cell lymphomas with localized presentation.

Marginal zone B-cell lymphomas (MZBCLs) are low-grade lymphomas that characteristically lack CD5 expression. However, rare cases of MZBCL have been described in which the lymphomatous B cells coexpress CD5 (CD5+ MZBCL). In 7 of 9 reported CD5+ MZBCLs, there was evidence of widespread disease. We report four additional cases of CD5+ MZBCL. Three cases were low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) involving the lungs, the conjunctiva (bilateral), and the uterus. The remaining case represented a monocytoid B-cell lymphoma involving a posterior cervical lymph node. Southern blot hybridization did not show rearrangements of bc11 or bc12 in the three cases analyzed. All four patients had localized disease and normal peripheral blood counts. Staging of bone marrow biopsies from three patients did not show evidence of bone marrow involvement. The remaining patient had bilateral conjunctival lesions that were present for 15 years without progression. These four additional cases of CD5+ MZBCL show that this group of low-grade B-cell lymphomas occasionally may exhibit an atypical phenotype. Furthermore, in this study, the CD5+ MZBCLs were clinically localized at presentation, in contrast to most other reported cases, which have had dissemination to bone marrow or peripheral blood.

Aged↗

Intra-lesional low-dose interferon alpha2a therapy for primary cutaneous marginal zone B-cell lymphoma.

Primary cutaneous marginal zone lymphomas (pcMZL) belong to the primary cutaneous B-cell lymphoma (pCBCL) group. They are characterized by their restriction to the skin and a high likelihood of recurrence after various treatment modalities. First-line therapy consists of surgery and radiotherapy. These therapies may not always be indicated in young patients or in patients with pCBCL located in the face, where surgery or radiotherapy may leave disfiguring scars or radioderma. Eight patients with pcMZL were treated with intra-lesional injections of 3 million units of recombinant IFNalpha2a three times per week. The patients either did not want to undergo or did not qualify for surgical excision or radiotherapy due to inappropriate localization or age. All patients experienced complete tumor regression after a mean of 8.5 weeks (range 3 - 20). Two patients relapsed 4 and 12 months after treatment, respectively, but tumor regression was repeated after additional cycles of intra-lesional IFNalpha2a. All other patients remained free of disease. Thus, intra-lesional IFNalpha2a may represent a valuable alternative to surgery and radiotherapy as first-line treatment of pcMZL.

Adult↗

A case of diffuse large B-cell lymphoma transformed from immunoglobulin A-producing marginal zone B-cell lymphoma.

We present a rare case of diffuse large B-cell lymphoma transformed from immunoglobulin (Ig) A-secreting marginal zone B-cell lymphoma. A 62-year-old woman was admitted to our hospital for examination of a disseminated pulmonary shadow. Gradual swelling of bilateral axilla and right inguinal lymph nodes were noted after admission. Histological examination of the lymph node biopsy specimen revealed the appearance of marginal zone B-cell lymphoma. The surface Ig of lymphoma cells was IgA-kappa, which coincided with the class of monoclonal Ig found in the patient's serum. The lymph node swelling and pulmonary shadow subsided, and the serum IgA level was normalized by 3 courses of systemic chemotherapy. However, after 4 courses of treatment, new tumor lesions at the right chest wall and left arm progressively became apparent. The biopsy specimen of the tumor showed a feature of diffuse large B-cell lymphoma. Despite intensive chemotherapy, the patient died of spreading tumor burden into the central nervous system.

Cell Transformation, Neoplastic↗

Analysis of immunoglobulin V genes suggests cutaneous marginal zone B-cell lymphomas recognise similar antigens.

Extranodal marginal zone B-cell lymphomas (EMZL) are thought to develop from reactive infiltrates that represent immune responses to external or auto-antigens. Except for gastric EMZL, the antigenic triggers of EMZL development are mostly unknown, although a subset of cutaneous EMZL have been associated with Borrelia burgdorferi infections. To further evaluate whether a common antigen may be promoting the development of cutaneous EMZL, the immunoglobulin heavy chain variable (V(H)) genes from eight USA cases were sequenced and analysed. All used V(H)3 family gene segments, with 2/8 using the same V3-30 segment, 2/8 using the closely related V3-30.3 or V3-33 segments, 6/8 containing mutations and 2/7 showing evidence of ongoing mutation. Many of the complimentarity-determining region 3s (CDR3s) also showed similarities in length and displayed conserved amino acid motifs in the non-templated areas between the diversity and joining segments. The use of similar V(H) gene segments and conserved CDR3 amino acid motifs suggests that some of these cutaneous EMZL may bind the same or similar antigen via their surface immunoglobulin receptor. Analysis of the somatic mutations present in many of the V(H) genes was also consistent with antigen directly stimulating the growth of cutaneous EMZL.

Aged↗

[Cutaneous marginal zone B-cell lymphoma treated with rituximab].

Marginal zone B-cell lymphoma (MZL) is probably the most frequent of the primary cutaneous B-cell lymphomas, which are entities with indolent behavior. Clinically, it appears in middle-aged patients as papules, nodules or erythematous plaques, solitary or multiple, on the trunk and proximal part of the limbs. The prognosis is excellent despite frequent cutaneous recurrences. We present the case of a 40-year-old male who, after having several recurrences of MZL over a ten-year period, was treated with rituximab for multiple skin lesions. The patient showed full remission after four weeks of treatment, and developed cytokine-release syndrome after the first infusion of the drug.

Adult↗

Cytogenetic evidence for the origin of neoplastic cells in CD5-positive marginal zone B-cell lymphoma.

We describe an 87-year-old female patient presenting with a breast lump and axillary lymphadenopathy. Histological examination revealed the lump to be a CD5-positive extranodal marginal zone B-cell lymphoma (MZBCL) of mucosa-associated lymphoid tissue. Subsequent staging revealed disseminated disease including the head and neck region. Only 2 cases of CD5-positive MZBCL have undergone any form of cytogenetic analysis, and we report the first standard karyotype of such a case. This revealed partial trisomy 3,7q deletion and an additional marker chromosome. Notably, cells lacked the t(11;14) found at high frequency in mantle cell lymphoma and trisomy 12 found in B small lymphocytic lymphoma (B-SLL). These results, combined with the clinical, histological, and immunophenotypic picture, suggest a marginal zone origin for the neoplastic lymphocytes, rather than a relationship with mantle cell or small lymphocytic lymphoma.

Aged↗

Composite marginal zone B-cell lymphoma and classical Hodgkin's lymphoma: a clinicopathological study of 12 cases.

AIMS: Classical Hodgkin's lymphoma (cHL) rarely coexists as composite lymphoma with B-cell non-Hodgkin's lymphoma (B-NHL). We characterized 12 cases of composite marginal zone B-cell lymphoma (MZBL) and cHL by immunohistochemistry and molecular biology. METHODS AND RESULTS: Eight patients had gastric MZBL of mucosa-associated lymphoid tissue (MALT)-type, in five cases with a diffuse large B-cell lymphoma component. Concurrent cHL was observed either in the stomach wall, regional, or distant lymph nodes. One patient each had composite pulmonary/thyroid MZBL of MALT-type and cHL. In two cases, nodal composite MZBL and cHL was observed. cHL displayed features of mixed cellularity type in 10 cases, while in two cases only scattered Hodgkin- and Reed-Sternberg (H/RS) cells were noted. H/RS cells expressed CD30, multiple myeloma oncogene 1 protein (MUM1P), p53 (100%), CD15 (58%), CD20 (58%) and Epstein-Barr virus-associated LMP1 (50%). No t(11;18)(q21;q21) was detected in composite MZBL of MALT-type and cHL. CONCLUSIONS: MZBL and cHL may occur as composite lymphoma, possibly reflecting clonal lymphoma progression. Derivation from extranodal MZBL of MALT-type should be excluded in cases in which a diagnosis of primary extranodal cHL is considered.

Aged↗

[Extranodal marginal zone B-cell lymphoma of MALT-type].

Extranodal marginal zone B-cell lymphomas of the MALT type constitute, with around 8% of all B-cell lymphomas, the third most frequent lymphoma in the Western hemisphere. Their unifying characteristic principle is their origin in organs that are typically devoid of a regular lymphatic parenchyma ("primary" MALT). In contrast, "secondary" MALT is acquired in these sites by chronic inflammatory processes triggered by chronic infections or autoimmune diseases. The organotypic characteristics of these particular lymphoid tumours are also mirrored by organ-specific precursor lesions and in tumour biology. Usually, MALT-type lymphomas remain confined to their site of origin for a long time, disseminating only late during the course of the disease. Hence, they may be controlled by local treatment (excision, irradiation). Moreover, the distinctive genetic constitution of MALT-type lymphomas, although varying from organ to organ, indicates particular transformation pathways obviously related to the specific precursor lesion and, hence, of organ-specific quality.

Autoimmune Diseases↗

Primary lymphoma of the breast: a case of marginal zone B-cell lymphoma.

A case of primary marginal zone B-cell lymphoma in an elderly female patient is presented. Primary breast lymphomas are rare, comprising less than 1 per cent of all breast malignancies. These tumors have no clinical, pathologic, or radiologic pathognomonic features to distinguish them from breast adenocarcinoma. The diagnosis is usually made with an excisional biopsy, and more extensive surgery should be avoided. Delivery of radiation therapy and chemotherapy is tailored according to the histologic grade, stage of disease, and overall patient condition. This report summarizes the current knowledge reflected in the literature.

Aged↗

Ocular immune privilege: the eye takes a dim but practical view of immunity and inflammation.

The delicate visual axis that makes precise vision possible is highly vulnerable to the destructive potential of immunogenic inflammation. Immune privilege of the eye is the experimental expression of the way in which evolution has coped with the countermanding threats to vision of ocular infections and ocular immunity and inflammation. Ocular immune privilege has five primary features that account for its existence: blood:ocular barriers, absent lymphatic drainage pathways, soluble immunomodulatory factors in aqueous humor, immunomodulatory ligands on the surface of ocular parenchymal cells, and indigenous, tolerance-promoting antigen-presenting cells (APCs). Three manifestations of ocular immune privilege that have received the most extensive study are the intraocular microenvironment, which is selectively anti-inflammatory and immunosuppressive; the prolonged acceptance of solid tissue and tumor allografts in the anterior chamber; and the induction of systemic tolerance to eye-derived antigens. Anterior chamber-associated immune deviation is known to arise when indigenous, ocular APCs capture eye-derived antigens and deliver them to the spleen where multicellular clusters of these cells, natural killer T cells, marginal zone B cells, and gammadelta T cells create an antigen-presentation environment that leads to CD4(+) and CD8(+) alpha/beta T cells, which as regulators, suppress induction and expression of T helper cell type 1 (Th1) and Th2 immune expression systems. The ways the eye influences local and systemic immune responses to ocular antigens and pathogens carry risks to and benefits for mammalian organisms. As loss of sight is a powerful, negative-selecting force, the benefits of ocular immune privilege outweigh the risks.

Antigen-Presenting Cells↗

Analysis of mutations in immunoglobulin heavy chain variable region genes of microdissected marginal zone (MGZ) B cells suggests that the MGZ of human spleen is a reservoir of memory B cells.

The splenic marginal zone (MGZ), which surrounds the mantle zone (MTZ) in human splenic white pulp, contains a phenotypically and morphologically distinct population of B cells. The origin of MGZ B cells is uncertain. Whereas some experiments in rodents have suggested that they are a distinct cell lineage responsible for the immune response to T-independent type 2 antigens, others have suggested that they are memory B cells derived from a germinal center (GC) response. The progeny of a GC reaction is expected to have rearranged immunoglobulin (Ig) genes that are mutated. The distribution of mutations would be expected to reflect the selection of Ig by its affinity for antigen. We have analyzed rearranged Ig heavy chain variable region (VH) 6 and VH 4.21 genes in MGZ and MTZ B cells microdissected from frozen sections of human spleen to determine whether these genes have the properties of an affinity-selected memory B cell population. MTZ B cells contained germline Ig VH genes, confirming previous reports and providing an internal control for mutational analysis. MGZ B cells contained Ig VH genes that were mutated, showing that these cells had been subjected to a mutational mechanism characteristically active in the GC. The rearranged VH 6 genes showed patterns of mutation indicative of an antigen selection process, whereas the distribution of mutations in VH 4.21 genes was not characteristic of gene selection by conventional T-dependent antigen. Our studies provide the first evidence that the human splenic MGZ is a reservoir of memory B cells.

Adult↗

Monocytoid B cells are distinct from splenic marginal zone cells and commonly derive from unmutated naive B cells and less frequently from postgerminal center B cells by polyclonal transformation.

Monocytoid B cells represent a morphologically conspicuous B-cell population that constantly occurs in Toxoplasma gondii-induced Piringer's lymphadenopathy. Although widely believed to be closely related to splenic marginal zone B cells, neither this relationship, nor the B-cell differentiation stage of monocytoid B cells, nor their cellular precursors have been established. We have therefore examined monocytoid B cells for their expression of B-cell differentiation markers and the Ig isotypes at the RNA and protein level as well as for rearranged Ig heavy chain (H) genes and somatic mutations within the variable (V) region. The results obtained were compared with the corresponding features of other B-cell populations. The monocytoid B cells displayed immunophenotypical differences to all other B-cell populations. IgM and IgD expression was absent from most monocytoid B cells at the RNA and protein levels. Unrelated (polyclonal) Ig rearrangements were found in 85 of the 95 cells studied. Seventy-four percent of the rearranged VH genes were devoid of somatic mutations, whereas the remaining 26% carried a low number of somatic mutations. The majority of these showed no significant signs of antigen selection. This finding in conjunction with the predominantly unrelated Ig gene rearrangements indicates that most monocytoid B cells arise not by clonal proliferation but by transformation of polyclonal B cells. The B cells undergoing a monocytoid B-cell transformation are in the majority (74%) naive B cells, and only a minority are (26%) non-antigen-selected postgerminal center B cells. Thus, our data show that monocytoid B cells represent a distinct B-cell subpopulation.

Antigens, Differentiation, B-Lymphocyte↗