Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Lymphomas”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 685 records · Page 38Linked to original sources

Significance of cyclin D1 overexpression for the diagnosis of mantle cell lymphoma: a clinicopathologic comparison of cyclin D1-positive MCL and cyclin D1-negative MCL-like B-cell lymphoma.

Mantle cell lymphoma (MCL) is a distinct clinicopathologic entity of non-Hodgkin's lymphoma, characterized by a monotonous proliferation of small to medium-sized lymphocytes with co-expression of CD5 and CD20, an aggressive and incurable clinical course, and frequent t(11;14)(q13;q32) translocation. We examined 151 cases of lymphoma with MCL morphology from a viewpoint of cyclin D1 overexpression, which is now easily detectable by immunohistochemistry. 128 cases (85%) showed positive nuclear staining for cyclin D1, while the remaining 23 (15%) were negative. Except for cyclin D1 immunohistochemistry, current diagnostic methods, including morphological and phenotypical examinations, could not make this distinction. Although both the cyclin D1-positive and -negative groups were characterized by male predominance, advanced stages of the disease, frequent extranodal involvement, and low CD23 reactivity, the cyclin D1-positive group showed a higher age distribution (P =.04), larger cell size (P =.02), higher mitotic index (P =.01), more frequent gastrointestinal involvement (P =.05), higher international prognostic index score (P =.05), and lower p27(KIP1) expression (P <.0001). Of particular interest is that cyclin D1-positive MCL showed significantly worse survival than cyclin D1-negative lymphoma (5-year survival: 30% versus 86%, P =.0002), which was confirmed by multivariate analysis to be independent of other risk factors. These data suggest that cyclin D1-positive and -negative groups may represent different entities and that the former closely fits the characteristics of classical, typical MCL. We therefore propose that cyclin D1-positivity should be included as one of the standard criteria for MCL, and that innovative therapies for this incurable disease should be explored on the basis of the new criteria.

Adult↗

Seropositive rheumatoid arthritis with dermatomyositis sine myositis, angioimmunoblastic lymphadenopathy with dysproteinemia-type T cell lymphoma, and B cell lymphoma of the oropharynx.

Angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) is a rare lymphoproliferative disorder that often progresses to high grade T cell lymphoma. We describe a 63-year-old woman with longstanding seropositive rheumatoid arthritis who developed fever, cutaneous findings of dermatomyositis, a diffuse pruritic maculopapular rash, enlarged lymph nodes, polyclonal elevated serum gammaglobulins, and an IgG lambda paraprotein. Lymph node biopsies yielded tissue with characteristic changes of AILD and T cell lymphoma. Interleukin 6 (IL-6) was present during the early, active phase of disease, and circulating IL-6 and IL-2 were detected one month before tumor recurrence. Two years after AILD and T cell lymphoma were diagnosed, she developed a B cell lymphoma that involved the oropharynx.

Arthritis, Rheumatoid↗

In vivo T-cell immune response against anaplastic lymphoma kinase in patients with anaplastic large cell lymphomas.

BACKGROUND AND OBJECTIVES: Anaplastic lymphoma kinase (ALK) oncogenic fusion proteins, expressed in about 60% of anaplastic large cell lymphomas (ALCL), are tumor-specific molecular targets for such a malignancy. One of the promising ALK-targeted therapeutic options is cancer vaccination. In this study, we investigate whether ALK is a tumor-associated antigen suitable for immune interventions. DESIGN AND METHODS: The frequency and the functional phenotype of the anti-ALK CD8 precursor repertoire in freshly isolated peripheral blood mononuclear cells (PBMC) from healthy donors and ALK-positive patients were determined by major histocompatibility complex (MHC)/tetrameric analyses. The anti-ALK secondary immune responses were evaluated as PBMC-specific interferon (INF-gamma) release by ELISPOT. In addition, the ability of the anti-ALK immune response to specifically lyse ALK-positive lymphoma cells was investigated by in vitro stimulation with ALK-derived peptide p280-89. RESULTS: Tetrameric MHC/peptide complexes revealed high frequencies of CD8/ALK-tetramer-positive cells both in patients and in healthy individuals. However, the functional phenotype of the CD8/ALK-tetramer-positive lymphocytes showed the presence of effector and memory T lymphocytes only in patients. The anti-ALK cytotoxic T lymphocytes (CTL) of patients, but not healthy donors, displayed thresholds of activation comparable to those of CTL precursors of a recall antigen (influenza virus). A polyclonal ALK-specific tumor-reactive T-cell line was isolated from patients' peripheral blood lymphocytes. INTERPRETATION AND CONCLUSIONS: The presence of an anti-ALK effector/memory lymphocyte population in the peripheral blood of ALK-positive patients indicates an in vivo antigenic challenge. Thus, ALK is a lymphoma-associated antigen suitable for immune interventions. The high number of anti-ALK memory CD8 T cells present in patients' PBMC may represent a valid source of activated CTL suitable for cancer cell lysis.

Anaplastic Lymphoma Kinase↗

[Early transformation from follicular lymphoma to Burkitt lymphoma].

We report a rare case of follicular lymphoma which rapidly showed transformation to the Burkitt type of lymphoma after a treatment consisting of chemotherapy and irradiation. A 51-year-old male visited our hospital in August 2000 because of bilateral neck lymphadenopathy. He was diagnosed as having follicular lymphoma (grade 2) (clinical stage IIIA) with complex karyotypic abnormalities involving t(14 ; 18)(q32 ; q21) and CD20 expression. Initially he was followed as an outpatient without chemotherapy. Six months later, he was admitted because of hydronephrosis due to an intrapelvic tumor. He underwent chemotherapy with 4 courses of CHOP regimen following irradiation therapy and a partial response was obtained. Four months after initiation of the treatment, his disease recurred with numb chin syndrome. Bone marrow aspiration revealed bone marrow involvement by lymphoma cells which had a Burkitt-like appearance. A cytogenetic study using bone marrow blood showed complex abnormalities involving t(8 ; 22)(q24 ; q11) in addition to t(14 ; 18). In spite of salvage chemotherapy, the patient died in September 2001.

Burkitt Lymphoma↗

Burkitt-type lymphoma and reticulum-cell sarcoma. An unusual mixed form of two intracranial primary malignant lymphomas.

An unusual mixed type of two primary malignant lymphomas in a 50-year-old woman is reported. The patient had been in good health until 4 months before her death, when she developed epileptic seizures and neurological symptoms attributed to a lesion of the brainstem. Pathologic examination revealed a circumscribed tumor mass in the right parietal lobe, which was shown microscopically to contain two different forms of malignant lymphoma. The histologic features of the peripheral part of the tumor were typical of a Burkitt-type lymphoma, while the central part showed the features of a reticulum-cell sarcoma. The cells of the latter type diffusely infiltrated both temporal lobes, the cerebellum, and the brainstem. It is concluded that in the absence of systemic involvement, the Burkitt-type lymphoma also could be derived from the primitive reticulum cells of perivascular sheaths.

Brain Neoplasms↗

Progression of nodular poorly differentiated lymphocytic lymphoma to Burkitt's-like lymphoma.

Histologic conversion of nodular lymphomas to more aggressive patterns has been well described and occurs in 15% to 40% of cases. Most conversions have involved changes from nodular to diffuse patterns and often from small to larger cell types. Conversions to undifferentiated lymphomas, but not specifically to the Burkitt's type, have infrequently been described. This report describes three cases of nodular poorly differentiated lymphocytic lymphoma that converted to a Burkitt's-like lymphoma. Conversion was associated with short survivals, increasing lactate dehydrogenase (LDH) levels, and changes in DNA stemline, RNA content, and S-phase values, as determined by flow cytometry. Karyotypes in two cases revealed a t(14;18). Surface immunoglobulin could be demonstrated on transformed Burkitt's-like cells from lymph node in one case, but in none of the cases on cells from bone marrow.

Adult↗

Epstein-Barr virus-latent gene expression and tumor cell phenotype in acquired immunodeficiency syndrome-related non-Hodgkin's lymphoma. Correlation of lymphoma phenotype with three distinct patterns of viral latency.

We investigated 49 acquired immunodeficiency syndrome-related lymphomas (ARLs) for Epstein-Barr virus (EBV) by Southern blotting and in situ hybridization and, in positive cases, used cryostat immunohistology to compare EBV-latent gene expression (EBV encoded small RNA-1 [EBER-1], EBV nuclear antigen-2 [EBNA-2], latent membrane protein-1 [LMP-1] and host cell immunophenotype (CD11a, CD18, CD54, CD58, CD21, CD23, CD30, CD39, CDw70, immunoglobulin) patterns with those reported in other EBV infections. EBV+ immunoblast-rich/large cell ARLs (n = 22) showed three patterns of latency: broad (EBER+EBNA-2+/LMP-1+; n = 9), reminiscent of a lymphoblastoid cell line phenotype; restricted (EBER+/EBNA-2-/LMP-1-; n = 6), similar to endemic Burkitt's lymphoma; and intermediate (EBER+/EBNA-2-/LMP-1+; n = 7), a pattern rarely described in vitro but seen in certain EBV-related malignancies. EBNA-2 expression was associated with extranodal lymphomas. EBV+ Burkitt-type ARLs (n = 11) usually showed the restricted latency pattern (n = 8), but some expressed the intermediate form (n = 3). Adhesion (CD54, CD58) and activation (CD30, CD39, CDw70) molecule expression varied with morphology (immunoblast-rich/large cell versus Burkitt-type), but was not independently correlated with EBV-positivity. CD30 and LMP-1 expression were associated. ARLs show heterogeneity regarding both the presence of EBV and latency pattern. Comparison of these phenotypically distinct lymphoma groups with known forms of EBV infection provides clues to their possible pathogenesis.

Adult↗

Centrocytic lymphoma: a morphometric study with comparison to other small cleaved follicular center cell lymphomas and genotypic correlates.

Centrocytic lymphoma (ML,CC) is distinguished from other cleaved follicular center cell (FCC) lymphomas in the Kiel classification by the lack of noncleaved FCC and not by morphological differences between the centrocytes (cleaved cells). Immunophenotypic and genotypic studies, however, have shown that the centrocytes in ML,CC are distinct from those of other small cleaved FCC lymphomas (ML,FCC,SC). To morphologically compare the cells of ML,CC with nine previously studied ML,FCC,SC and to relate the findings in ML,CC to the varied descriptions of lymphomas of intermediate differentiation, a morphometric analysis of 22 ML,CC was performed. Nuclei in ML,CC were, on average, significantly larger, rounder, and had less frequent nucleoli than those in ML,FCC,SC; however, the proportion of small round lymphocytes did not differ. Among the ML,CC, the only apparent immunophenotypic/genotypic correlate that was identified was greater nuclear ellipticity for the biopsies lacking chromosome 11q13 bcl-1 or PRAD1 rearrangement. Repeat biopsies in four patients with ML,CC showed an increase in nuclear size. These data demonstrate that a lack of transformed cells is not the only morphological difference between ML,CC and ML,FCC,SC. The morphological distinction, however, is not based on the proportion of small round lymphocytes present. In addition, the morphometric parameters illustrate the nuclear variability among ML,CC and demonstrate how the disease may evolve over time.

Cell Nucleus↗

HOXC4, HOXC5, and HOXC6 expression in non-Hodgkin's lymphoma: preferential expression of the HOXC5 gene in primary cutaneous anaplastic T-cell and oro-gastrointestinal tract mucosa-associated B-cell lymphomas.

Most of the 39 members of the homeobox (HOX) gene family are believed to control blood cell development. HOXC4 and HOXC6 gene expression levels increase with differentiation of lymphoid cells. In contrast, HOXC5 is not expressed in the lymphoid lineage, but was found in lymphoid cell lines, representing the neoplastic equivalents of various differentiation stages of T and B lymphocytes. In the present study, we investigated the HOXC4, HOXC5, and HOXC6 gene expression pattern in 89 non-Hodgkin's lymphomas (NHLs) of different histologic subtypes and originating from different sites. Using RNA in situ hybridization and semiquantitative reverse transcription-polymerase chain reaction, we found expression of HOXC4 in 83 of 88 and HOXC6 in 77 of 88 NHLs and leukemias investigated. In contrast, HOXC5 expression was found in only 26 of 87 NHLs and appeared to be preferentially expressed by two specific subsets of lymphomas, ie, primary cutaneous anaplastic T-cell lymphomas (9 of 9) and extranodal marginal zone B-cell lymphomas (maltomas; 7 of 9). These results indicate that, in contrast to HOXC4 and HOXC6, HOXC5 shows a type- and site-restricted expression pattern in both T- and B-cell NHLs.

Gastric Mucosa↗

Pyothorax-associated lymphoma: relationship with Epstein-Barr virus, human herpes virus-8 and body cavity-based high grade lymphomas.

Pyothorax-associated lymphoma (PAL) is a newly-described entity developing several decades after artificial pneumothorax treatment for pulmonary or pleural tuberculosis. It is known to be associated with Epstein-Barr virus (EBV) with constant expression of the two latent membrane proteins: latent membrane protein (LMP)-1 and EBV-associated nuclear antigen (EBNA)-2. We are reporting three new cases of PAL. All of the tumours were of B-cell lineage and classified as large-cell diffuse lymphomas according to the International Working Formulation for the Classification of Lymphomas. The EBV genome was detected in two of the cases with LMP-1 and EBNA-2 expression. No EBV could be detected in the third case suggesting that different mechanisms may be involved in the pathogenesis of the disease. Body cavity-based high grade lymphomas (BCBL) represent a new disease, developing mainly in human immunodeficiency virus (HIV) infected patients: the tumoural cells often contain both human herpes virus (HHV)-8 (or Kaposi's sarcoma herpes virus) and EBV genomes, suggesting that these viruses might co-operate in the pathogenesis of the disease. The pleural location and the association of EBV have led to speculation that PAL could also be related to HHV-8 infection. However, no HHV-8 genome could be detected in any of the 14 tested cases already reported in the literature nor in the two cases we studied (one EBV-positive and one EBV-negative), suggesting that PAL and BCBL are two different entities.

Aged↗

Lymph node classification systems in cutaneous T-cell lymphoma. Evidence for the utility of the Working Formulation of Non-Hodgkin's Lymphomas for Clinical Usage.

BACKGROUND: This study was undertaken to compare three classification schemes used to evaluate lymph nodes (LN) obtained from patients with cutaneous T-cell lymphoma (CTCL): a modified Rappaport classification, the National Cancer Institute-Veterans Administration (NCI-VA) classification based on the relative numbers of cerebriform cells in the paracortical areas, and the Dutch classification based on the presence of cerebriform cells with large nuclei in mycosis fungoides (MF) and diffuse infiltration by cerebriform cells in Sézary syndrome. METHODS: A study set of 195 LN obtained from patients with CTCL (MF, Sézary syndrome, and nonepidermotropic T-cell lymphomas) and 14 LN from patients with benign dermatoses was reviewed independently by three groups of pathologists familiar with each classification system. RESULTS: Each classification system provided useful prognostic information. However, contrary to prior reports, no significant difference in survival was apparent in patients with uneffaced LN when classified according to the NCI-VA (LN0-2 versus LN3) or Dutch (Gr0-1 versus Gr2) ratings. In addition, all classification systems demonstrated a poor survival time associated with effaced LN. By combining results from the modified Rappaport and Dutch classifications, three prognostic groups could be identified based on cell morphology: a low-grade category with a small cell histologic subtype (median survival time, 40 months); a high-grade immunoblastic subtype (median survival time, 9 months) composed of cells with an oval nucleus containing a large, usually solitary central nucleolus; and an intermediate-grade category composed of all cases without the distinctive small cell and immunoblastic morphologies (median survival time, 26 months). CONCLUSIONS: The authors propose that clearly involved LN in CTCL can be categorized on the basis of cell morphology into prognostic groups analogous to what has been proposed for the Working Formulation for Non-Hodgkin's Lymphomas for Clinical Usage.

Cell Transformation, Neoplastic↗

Differential response to H. pylori eradication therapy of co-existing diffuse large B-cell lymphoma and MALT lymphoma of stomach-significance of tumour cell clonality and BCL10 expression.

We recently reported that low-grade mucosa-associated lymphoid tissue lymphoma (MALToma) and diffuse large B-cell lymphoma (DLBCL) with MALToma (DLBCL[MALT]) of stomach are equally responsive to H. pylori eradication therapy (HPET) and that H. pylori-independent status is closely associated with nuclear translocation of BCL10. However, co-existing MALToma and DLBCL components of gastric DLBCL(MALT) may respond differentially to HPET and the underlying mechanism remains unclear. Tumour tissue samples from 18 patients with microdissectable co-existing MALToma and DLBCL cells were studied. The clonality of lymphoma cells was examined by polymerase chain reaction-based amplification of the CDR3 region of the IgH gene and confirmed by DNA sequence analysis. BCL10 expression was determined by immunohistochemistry. Differential response of co-existing MALToma and DLBCL to HPET was defined as complete eradication of one component while the other component remained. Five (27.8%) of the 18 patients showed different IgH gene rearrangements in the two components and three (60%) of these five patients had differential response of MALToma and DLBCL to HPET. By contrast, 13 patients showed identical IgH gene rearrangements and only one (8%) of them had differential response of the two components to HPET (p = 0.044). Further, all four patients with differential response of MALToma and DLBCL to HPET showed nuclear expression of BCL10 in the H. pylori-independent component and cytoplasmic expression of BCL10 in the H. pylori-dependent component while the expression patterns of BCL10 were identical in both of these components in the 14 patients who had similar tumour response to HPET. We conclude that different clonality is a common reason for the differential response of co-existing MALToma and DLBCL of gastric DLBCL(MALT) to HPET and that immunohistochemical examination of BCL10 expression may help to identify the co-existence of these components.

Adaptor Proteins, Signal Transducing↗

Transcript profiling in peripheral T-cell lymphoma, not otherwise specified, and diffuse large B-cell lymphoma identifies distinct tumor profile signatures.

To glean biological differences and similarities of peripheral T-cell lymphoma-not otherwise specified [PTCL-NOS] to diffuse large B-cell lymphoma (DLBCL), a transcriptosome analysis was done on five PTCL-NOS and four DLBCL patients and validated by quantitative real-time reverse transcription-PCR on 10 selected genes. Normal peripheral blood T cells, peripheral blood B cells, and lymph node were used as controls. The resultant gene expression profile delineated distinct "tumor profile signatures" for PTCL-NOS and DLBCL. Several highly overexpressed genes in both PTCL-NOS and DLBCL involve the immune network, stroma, angiogenesis, and cell survival cascades that make important contributions to lymphomagenesis. Inflammatory chemokines and their receptors likely play a central role in these complex interrelated pathways: CCL2 and CXCR4 in PTCL-NOS and CCL5 and CCR1 in DLBCL. Highly overexpressed oncogenes unique to PTCL-NOS are SPI1, STK6, alpha-PDGFR, and SH2D1A, whereas in DLBCL they are PIM1, PIM2, LYN, BCL2A1, and RAB13. Oncogenes common to both lymphomas are MAFB, MET, NF-kappaB2, LCK, and LYN. Several tumor suppressors are also down-regulated (TPTE, MGC154, PTCH, ST5, and SUI1). This study illustrates the relevance of tumor-stroma immune trafficking and identified potential novel prognostic markers and targets for therapeutic intervention.

Base Sequence↗

Non-Hodgkin's lymphoma after primary Hodgkin's disease in the German Hodgkin's Lymphoma Study Group: incidence, treatment, and prognosis.

PURPOSE: The cumulative incidence for non-Hodgkin lymphoma's (NHL) after primary Hodgkin's disease (HD) ranges between 1% and 6%. To investigate the course of disease for secondary NHL, we retrospectively analyzed patients treated within clinical trials of the German Hodgkin's Lymphoma Study Group (GHSG) since 1981. PATIENTS AND METHODS: From 1981 to 1998, the GHSG conducted three generations of clinical trials for the treatment of primary HD involving a total of 5,406 patients. Reference histology by an expert panel was obtained for 4,104 of the patients. Data on incidence, treatment, and outcome of secondary NHL were updated in March 1999. RESULTS: At first diagnosis of HD, the pathologists rejected 114 (2.1%) of 5,520 cases initially diagnosed as HD and rediagnosed them as primary NHL. Fifty-two (0.9%) of the remaining 5,406 patients developed a secondary NHL. One patient was excluded from further analyses because of insufficient documentation. Six patients had no further therapy because of patient refusal (n = 1) or rapidly progressive disease (n = 5). For the remaining 45 patients, overall response rate was 43% (36% complete response and 7% partial response). The actuarial 2-year freedom from treatment failure (FFTF) and overall survival (OS) for all patients was 24% and 30%, respectively, and for patients with diffuse large-cell lymphoma, it was 28% and 35%, respectively. Time of occurrence of secondary NHL after first diagnosis of HD and variables employed in the age-adjusted International Prognostic Factor Index (IPFI) significantly influenced treatment outcome. CONCLUSION: In the GHSG, the incidence of secondary NHL with 0.9% is relatively low compared with previously reported series. The prognosis of secondary NHL seems dismal and is significantly influenced by time of occurrence and the age-adjusted IPFI. In a subset of patients with secondary NHL, long-term disease-free survival could be achieved.

Actuarial Analysis↗

Principles of the revised European-American Lymphoma Classification (from the International Lymphoma Study Group).

The International Lymphoma Study Group has proposed a consensus classification for lymphoid neoplasms. Lymphoid neoplasms are defined as distinct biological entities, based on a combination of morphologic, immunophenotypic, genetic, and clinical features. Each distinct disease may have a range of histologic grade and clinical aggressiveness. Although many distinct diseases can now be recognized, three of them (follicular lymphoma, diffuse large B-cell lymphoma, and Hodgkin's disease) account for the majority of the cases seen in Europe and the USA. Recognition of distinct disease entities is essential in order to develop and test effective therapies.

Europe↗

Expression of cytotoxic molecules in intestinal T-cell lymphomas. The German Study Group on Intestinal Non-Hodgkin Lymphoma.

Intestinal T-cell lymphoma (ITCL) represents a subgroup of peripheral T-cell lymphomas which is thought to arise from alpha beta intraepithelial T-lymphocytes. Since these lymphocytes may contain cytotoxic molecules, the question of whether this also holds true for ITCL arises. Twenty ITCL cases were examined for the presence of granzyme B, perforin, and T-cell-restricted intracellular antigen (TIA-1)/granule membrane protein of 17 kD (GMP-17). Two molecules with restricted expression in cytotoxic cells, granzyme B and perforin, were detected by immunocytochemistry and by in situ hybridization with an isotopically labelled RNA probe, respectively. Immunocytochemistry was also performed with the antibody 2G9, which recognizes two molecules, one expressed by cytotoxic cells (TIA-1) and the other found in granulocytes and cytotoxic cells (GMP-17). Granzyme B, TIA-1/GMP-17, and perforin were found in the neoplastic cells of 16/19 cases, 19/20 cases, and 16/17 cases, respectively, of ITCL, but not in the tumour cells of the control group, which consisted of intestinal B-cell lymphomas (five cases) and CD8-negative peripheral nodal T-cell lymphomas (six cases). At least one of these molecules was expressed in the tumour cells of all ITCL cases. 2G9 proved to be the most sensitive immunohistological marker, since reactivity with this antibody was not only observed in the highest number of cases, but also found in high numbers of neoplastic cells in positive cases. In conclusion, ITCL appears to show cytotoxic differentiation in all cases. In conjunction with immunophenotypic and genotypic data, our results support a uniform derivation of this tumour from intraepithelial alpha beta cytotoxic T-lymphocytes.

Adult↗

Expression of Epstein-Barr virus latent infection genes and oncogenes in lymphoma cell lines derived from pyothorax-associated lymphoma.

Malignant lymphomas frequently develop in the pleural cavity of patients with long-standing pyothorax. The term pyothorax-associated lymphoma (PAL) has been proposed for this type of tumor. Most PALs are diffuse lymphomas of the B-cell type and contain Epstein-Barr virus (EBV) DNA. We have established 2 lymphoma cell lines from biopsy specimens of PAL cases, OPL-1 and OPL-2, and examined their growth characteristics and the expression of EBV latent infection genes and oncogenes. OPL-2 exhibited a more rapid growth and higher saturation density than OPL-1, and only OPL-2 exhibited colony-forming activity in soft agar. OPL-1 and -2 were positive for B-cell differentiation markers and showed clonal surface immunoglobulins. Both line contained a single predominant form of episomal EBV DNA, indicating clonal cellular proliferation of an EBV-infected progenitor cell. OPL-1 and -2 contained type B and A EBV genome, respectively. Expression of EBV nuclear antigen (EBNA)2 mRNA and protein was detected by Northern and Western blot analysis in OPL-1, but not in OPL-2. On the other hand, the expression of latent membrane protein (LMP)1 mRNA in both OPL-1 and -2 was extremely weak and detectable only by reverse transcription-polymerase chain reaction. Protein expression of LMP1 was not observed by Western blot analysis or immunocytochemistry. Both lines expressed c-myc mRNA. Only OPL-1 expressed mRNA of c-fgr, an oncogene whose expression is upregulated by EBNA2. Both OPLs expressed bcl-2 mRNA without detectable expression of LMP1 protein.

Aged↗

Histiocytic lymphoma with sclerosis arising from a nodular lymphoma with a special stromal reaction.

Histiocytic lymphoma with sclerosis was found together with a small nodular lymphoma in a cervical lymph node biopsy from a 48-year-old man. Since the cellular origin of this entity is unclear and its ultrastructure has not been described before, we processed formalin-fixed samples for electron microscopy, which revealed three cell types: small lymphocytes with cleaved nuclei, large lymphocytes with vesticular noncleaved nuclei, and mesenchymal stromal cells occasionally bearing desmosomes or hemidesmosomes. In addition, there was an increase of the intercellular connective tissue, which consisted of a mixture of normal and fibrous long spacing collagen fibers. The results indicate that histiocytic lymphoma with sclerosis can evolve from a nodular lymphoma, and that diagnostic information can be obtained by electron microscopy of tissue samples previously fixed in formalin.

Connective Tissue↗