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T F E Barth

Publications and source records attributed to T F E Barth.

6 recordsLinked to original sources

Transcriptional profiling suggests that secondary and primary large B-cell lymphomas of the gastrointestinal (GI) tract are blastic variants of GI marginal zone lymphoma.

The pathogenetic relationship of marginal zone B-cell lymphoma (MALT lymphoma) of the gastrointestinal (GI) tract and eventually co-existing aggressive B-cell lymphoma and primary aggressive B-cell lymphoma remains to be elucidated. The RNA of laser-microdissected cells was isolated and amplified from small and/or large cell compartments of eight MALT lymphomas (small cell lymphoma, SCL), 14 GI diffuse large B-cell lymphomas (large cell lymphoma, LCL), and ten GI B-cell lymphomas with composite small and large cell compartments (ComL) and expression analyses were performed using cDNA arrays. Hierarchical cluster analysis clearly separated SCL and LCL and the small and large cell compartments of ComL. Likewise, cluster analysis with all samples of SCL, LCL, and ComL yielded two main 'small cell' and 'large cell' branches. Furthermore, 60 genes were differentially expressed between SCL and LCL, and 82 genes between the small and large cell components of ComL; 26 genes were discriminators in both settings. Use of the profiles of ComL as training sets for class prediction resulted in 95% accuracy for the classification of SCL and LCL. Collectively, the data strongly suggest that both secondary and primary aggressive B-cell lymphomas of the GI tract are blastic marginal zone lymphomas.

Gastrointestinal Neoplasms↗

[Mediastinal large B-cell lymphoma].

Mediastinal B-cell lymphoma is a locally highly aggressive tumour which was first described in the early 1980s. The incidence is about 2-3% of all non-Hodgkin's lymphomas. The conceptional evolution of this lymphoma entity was hampered by its low incidence and the broad spectrum of morphological variants present. However, since mediastinal B-cell lymphoma has distinct morphological, immunological, genetic, and clinical features, it has been listed in the revised European-American Classification of Lymphoid Neoplasms (REAL-Classification) since 1994 as a variant of diffuse large B-cell lymphoma. In the World Health Organization classification of malignant lymphomas, mediastinal B-cell lymphoma is now listed with an own disease code (ICD-9679/3).

Humans↗

Mutations of the tumor suppressor gene SOCS-1 in classical Hodgkin lymphoma are frequent and associated with nuclear phospho-STAT5 accumulation.

The suppressors of cytokine signaling (SOCS) are critically involved in the regulation of cellular proliferation, survival, and apoptosis via cytokine-induced JAK/STAT signaling. SOCS-1 silencing by aberrant DNA methylation contributes to oncogenesis in various B-cell neoplasias and carcinomas. Recently, we showed an alternative loss of SOCS-1 function due to deleterious SOCS-1 mutations in a major subset of primary mediastinal B-cell lymphoma (PMBL) and in the PMBL line MedB-1, and a biallelic SOCS-1 deletion in PMBL line Karpas1106P. For both cell lines our previous data demonstrated retarded JAK2 degradation and sustained phospho-JAK2 action leading to enhanced DNA binding of phospho-STAT5. Here, we analysed SOCS-1 in laser-microdissected Hodgkin and Reed-Sternberg (HRS) cells of classical Hodgkin lymphoma (cHL). We detected SOCS-1 mutations in HRS cells of eight of 19 cHL samples and in three of five Hodgkin lymphoma (HL)-derived cell lines by sequencing analysis. Moreover, we found a significant association between mutated SOCS-1 of isolated HRS cells and nuclear phospho-STAT5 accumulation in HRS cells of cHL tumor tissue (P < 0.01). Collectively, these findings support the concept that PMBL and cHL share many overlapping features, and that defective tumor suppressor gene SOCS-1 triggers an oncogenic pathway operative in both lymphomas.

Amino Acid Sequence↗

Wotherspoon criteria combined with B cell clonality analysis by advanced polymerase chain reaction technology discriminates covert gastric marginal zone lymphoma from chronic gastritis.

BACKGROUND AND AIMS: Gastric mucosa associated lymphoid tissue lymphoma is a well defined B cell lymphoma yet often impossible to distinguish from severe chronic gastritis on morphological grounds alone. Therefore, it was suggested to use the clonality of the immunoglobulin (Ig) heavy chain (H) genes, as detected by polymerase chain reaction (PCR), as a decisive criterion. However, there is controversy as to whether B cell clonality also exists in chronic gastritis, hence rendering this approach futile at present. METHODS: An expert panel re-examined the histology and immunohistochemistry of a total of 97 cases of gastric biopsies, including clearcut marginal zone lymphoma, chronic gastritis, and ambiguous cases, applying the Wotherspoon criteria on the basis of haematoxylin-eosin and CD20 immunostainings. In addition, a new and advanced PCR system for detection of clonal IgH gene rearrangements was independently applied in two institutions in each case. RESULTS: The overall IgH clonality assessments of both institutions were in total agreement. Overt lymphoma (Wotherspoon score 5) was clonal in 24/26 cases. Chronic gastritis (Wotherspoon scores 1 and 2) was not clonal in 52/53 cases; the clonal case being Wotherspoon score 2. Of 18 cases with ambiguous histology (Wotherspoon scores 3 and 4) four were clonal. CONCLUSIONS: Using advanced PCR technology, clonal gastritis is extremely rare, if it exists at all. Thus B cell clonality in Wotherspoon 3 and 4 cases is regarded as suitable for definitively diagnosing gastric marginal zone lymphoma.

Algorithms↗

Segmental chromosomal aberrations and centrosome amplifications: pathogenetic mechanisms in Hodgkin and Reed-Sternberg cells of classical Hodgkin's lymphoma?

Tumor cell metaphases of classical Hodgkin's lymphoma (cHL) characteristically display highly rearranged karyotypes with chromosome numbers in the hyperploid range and marked intraclonal variability. The causes of this cytogenetic pattern remain largely unknown. An unusual type of chromosomal abnormality coined as segmental chromosomal aberration (SCA) has been recurrently observed in HL cell lines and was suggested to be associated with ribosomal DNA (rDNA) rearrangements. Moreover, centrosome abnormalities provoking deficient chromosome segregation have been reported in many solid tumors and also in cHL cell lines. Whether SCA, rDNA rearrangements or centrosome abnormalities also occur in primary cHL is not yet known. Thus, we performed extensive molecular cytogenetic and immunohistological studies in two cHL cases. Both cases presented SCA associated with genomic gains of the REL and JAK2 loci, respectively. The SCA involving JAK2 was associated with rDNA rearrangements. The absolute centrosome size of HRS cells in both cases was significantly larger than in non-HRS cells, but the relative centrosome size of HRS cells corrected for nuclear size was in the same range as that of the non-neoplastic cells. These findings demonstrate that the various mechanisms associated with chromosomal instability warrant a more detailed characterization in cHL.

Adult↗