Recombinant human arginase induced caspase-dependent apoptosis and autophagy in non-Hodgkin's lymphoma cells.

Arginase, an arginine-degrading enzyme, has gained increased attention recently as a new experimental therapeutics for a variety of malignant solid cancers. In this study, we found that recombinant human arginase (rhArg) could induce remarkable growth inhibition, cell cycle arrest, and caspase-dependent apoptosis in Raji and Daudi non-Hodgkin's lymphoma (NHL) cells through arginine deprivation. Interestingly, rhArg-treatment resulted in the appearance of autophagosomes and upregulation of microtubule-associated protein light chain 3 II, indicating that rhArg induced autophagy in lymphoma cells. Further study suggested that mammalian target of rapamycin/S6k signaling pathway may be involved in rhArg-induced autophagy in NHL cells. Moreover, blocking autophagy using pharmacological inhibitors (3-methyladenine and chloroquine) or genetic approaches (small interfering RNA targeting autophagy-related gene 5 and Beclin-1) enhanced the cell killing effect of rhArg. These results demonstrated that rhArg has a potent anti-lymphoma activity, which could be improved by in combination with autophagic inhibitors, suggesting that rhArg, either alone or in combination with autophagic inhibitors, could be a potential novel therapeutics for the treatment of NHL.

Open or closed nuclear membrane? A question to help distinguish malignant lymphoma from carcinoma and sarcoma.

OBJECTIVE: To describe a cytomorphologic criterion that may help improve diagnostic safety in morphologic differentiation of non-Hodgkin's lymphoma (NHL) from carcinoma or sarcoma and investigate the significance of this cytomorphologic phenomenon. STUDY DESIGN: Eighty-two smears of NHL, carcinoma and sarcoma smears were examined. Forty-five smears were from patients with carcinoma and 35 from patients with NHL. The remaining 2 smears were from patients with sarcoma. RESULTS: In 40 of 46 smears of carcinoma or sarcoma the nuclear membrane was assessed as "open" by the observer. In 6 smears the membrane was assessed as "closed. " In 30 of 35 smears with histologically confirmed NHL, the membrane was estimated as being closed. In the remaining 5 smears it was assessed as open. The sensitivity of evaluating the parameter as open or closed membrane was 87% and the specificity was 86%. The negative predictive value was 89%, and the positive predictive value was 83%. CONCLUSION: We suggest that the presence of an open or closed nuclear membrane may be helpful in differentiation of malignant lymphoma from carcinoma or sarcoma and may help improve diagnostic safety in daily practice.

[Granular apparatus ov nucleolonema nucleoli of the immature lymphoid cells in lymphoproliferative diseases]. / Granuliarnyi apparat nuleolonemnykh iadryshek nezrelykh limfoidnykh kletok pri limfoproliferativnykh zabolevaniiakh.

A study of argentophil granules within and outside of the nucleolonem nucleoli along the area of immature lymphoid cells (5655) revealed, in Non-Hodgkin's lymphoma and benign hyperplasia, differential-and-diagnostic, dimensional, quantitative and topographic parameters, which expand the possibilities of the cytological method in verifying reliably the biological nature of lymphoproliferative diseases.

Human pulmonary chimerism after hematopoietic stem cell transplantation.

Many of the body's tissues once thought to be only locally regenerative may, in fact, be actively replaced by circulating stem cells after hematopoietic stem cell transplantation. Localization of donor-derived cells ("chimerism") has recently been shown to occur in the lungs of mice after either hematopoietic stem cell transplantation or infusion of cultured marrow. To determine whether tissues of the human lung might be similarly derived from extrapulmonary sources, we examined lung specimens from a retrospective cohort of female allogeneic hematopoietic stem cell transplant recipients who received stem cells from male donors. Tissue samples from three such patients who had undergone diagnostic lung biopsy or autopsy were examined. Slides were stained by immunohistochemistry for cytokeratin (epithelium) and platelet endothelial cell adhesion molecule, CD31 (PECAM) (endothelium) and were imaged and then examined by fluorescent in situ hybridization analysis to identify male cells. The resulting overlapping in situ hybridization and immunohistochemistry images were examined for the presence and, if present, cell type of donor cells in the lung. We found significant rates of epithelial (2.5-8.0%) and endothelial (37.5-42.3%) chimerism. These results suggest that significant chimerism of the human lung may follow hematopoietic stem cell transplantation and that adult human stem cells could potentially play a therapeutic role in treatment of the damaged lung.

[Morphometric study of lymphoid cells from non-Hodgkin lymphoma and reactive lymphadenitis]. / Morfometricheskie issledovaniia limfoidnykh kletok nekhodzhkinskikh limfom i reaktivnykh limfadenitov.

A study of morphometric parameters of lymphoid cells reveals reliably higher parameters of area, perimeter as well as coefficients of shape and nucleus diameter of malignant cells in non-Hodgkin lymphoma versus the analogical indices observed in benign lymphoproliferative processes, which is an objective differential-diagnostic feature contributing to an accurate identification of lymphoproliferative lesions.

[Main morphofunctional types of blast cell nucleoli in non-Hodgkin lymphoma and benign hyperplasia]. / Osnovnye morfofunktsional'nye tipy iadryshek blastnykh kletok pri nekhodzhkinskikh limfomakh i dobrokachestvennykh giperplaziiakh.

Expression of main morphofunctional types of blast cell nucleoli in lymphomas and benign hyperplasia was compared in the cytological material of 38 patients for revealing additional differential cytological signs of malignant transformation of lymphoid cells. Cytogenetic criteria of malignant transformation of the blast population of lymphoid cells were determined.

Utilización de la citomorfología junto con la citometría de flujo en material obtenido por PAAF en lesiones linfoproliferativas. Comparación de coste frente a la biopsia / Use of cytomorphology in combination with flow cytometry in material obtained through FNA in lymphoproliferative lesions. Costs compared with biopsy

Introducción: El uso de la punción-aspiración con aguja fina (PAAF) junto con la citometría de flujo (CMF) constituye una alternativa diagnóstica frente a la biopsia. Objetivos: Se compara la eficacia diagnóstica de la citología más CMF en enfermedades linfoproliferativas y se calcula el coste de la PAAF frente a la biopsia. Resultados: La sensibilidad de la CCF es del 96 por ciento en procesos reactivos y la especificidad del 97 por ciento. En el diagnóstico de los linfomas no Hodgkin, teniendo en cuenta el tipo, la sensibilidad es del 89 por ciento, la especificidad del 100 por ciento y la eficacia del 95 por ciento. La citología unida a la CMF resulta cuatro veces más barata que la biopsia. Conclusiones: Las técnicas de CMF e inmunocitoquímica para aplicar a las PAAF son aconsejables en determinados casos por su rapidez, economía, menor morbilidad y menores molestias para el paciente. Otra perspectiva a considerar es la aplicación de técnicas de biología molecular (AU)

Correlation between apoptotic figure counting and the TUNEL technique.

OBJECTIVE: To compare histologic detection of apoptotic (AP) figures and terminal transferase UTP nick end labeling (TUNEL) detection in colorectal carcinomas and lymphomas. STUDY DESIGN: We evaluated the percentage of AP cells by AP figure counting and by the TUNEL technique in formalin-paraffin material from 39 tumors--29 colorectal carcinomas and 10 non-Hodgkin's lymphomas. The Lucia G image analysis system (Laboratory Imaging, Prague, Czech Republic) was used for cellularity evaluation and AP counting. RESULTS: On average, 0.81 +/- 0.5% AP cells were detected by figure counting; 0.91 +/- 0.35% were identified by TUNEL. A statistically high correlation between these techniques was found using Pearson's correlation coefficient (r = .56, P < .001). TUNEL, although probably more sensitive, was difficult to standardize. CONCLUSION: AP figure counting seems to be the method of choice for routine work, particularly because of its cost effectiveness and reproducibility.

Mantle cell lymphoma in leukemic phase: characterization of its broad cytologic spectrum with emphasis on the importance of distinction from other chronic lymphoproliferative disorders.

BACKGROUND: Mantle cell lymphoma is a mature, virgin B-cell neoplasm characterized immunologically by a panB+, CD5+, CD23-, cyclin D1+ phenotype and genetically by t(11;14)(q13;q32) with overexpression of the cyclin D1 (bcl-1) gene. It usually presents as advanced stage disease, involving lymph nodes, spleen, bone marrow, and extranodal sites, particularly the gastrointestinal tract. However, frank leukemic presentation with high white cell counts is uncommon and can be difficult to distinguish from other chronic lymphoproliferative disorders. The aim of this study was to characterize the morphologic spectrum of leukemic mantle cell lymphoma. METHODS: During the period July 1994 through October 1998, 14 patients with mantle cell lymphoma in leukemic phase were diagnosed at the Department of Pathology, Queen Elizabeth Hospital, Hong Kong. The diagnosis of mantle cell lymphoma was based on histologic and immunocytochemical findings and was confirmed by cyclin D1 immunoreactivity in all cases. The clinical records and laboratory results were reviewed. Peripheral blood smears, bone marrow, and other tissue biopsies were examined, with particular attention to the cytologic features of the leukemic mantle cells. RESULTS: Mantle cell lymphoma in leukemic phase showed a very aggressive clinical course. Eight patients died at a mean of 13 months, and only 1 patient was disease free. Morphologically, the leukemic mantle cells exhibited a broad morphologic spectrum, with several cytologic patterns identified: 1) mixed small and medium-sized cells, 2) predominantly medium-sized cells, 3) predominantly large cells, and 4) giant cells. Despite variations in the size and nuclear shape, the leukemic mantle cells could usually be recognized by the nuclear irregularity and clefting, moderately dense but evenly distributed chromatin, small nucleoli, and scant cytoplasm. CONCLUSIONS: Recognition of the characteristic cytologic features of leukemic mantle cells can help to distinguish them from other chronic lymphoproliferative disorders. In contrast to the latter, the clinical course is aggressive and response to conventional chemotherapy is poor.

The abundant presence of Söderström bodies in cytology smears of fine-needle aspirates contributes to distinguishing high-grade non-Hodgkin's lymphoma from carcinoma and sarcoma.

Söderström bodies, also termed lymphoglandular bodies (LGB) and detectable in fine-needle aspiration cytology smears, have long been accepted as indicative of lymphoid tissues. To investigate the validity of this association, we examined 588 cytologic smears from high-grade non-Hodgkin's lymphoma (NHL), carcinoma, and sarcoma. Slides with lymphocytes in the vicinity of carcinoma and sarcoma cells had been excluded. Two independent observers scored smears to number, size, color, form, and smear background of the LGB. In 68 of 359 (19%) nonlymphoid malignancies rare (defined as < 1 LGB per high-power field) or occasional LGB (defined as 1-20 LGB per high-power field) were detectable. Half of these tumors consisted of melanomas, small cell lung carcinomas, and teratomas; the other half encompassed undifferentiated sarcomas. However, none of the smears obtained from carcinoma or sarcoma tissue had abundant LGB (defined as > 20 LGB per high-power field). When number of LGB was estimated to be abundant, the sensitivity for diagnosing a lymphoma was 54%; however, specificity was 100%. The difference in showing LGB between high-grade NHL and carcinoma/sarcoma was highly significant (p = 0.0001). The presence of abundant LGB in cytologic smears strongly suggests the diagnosis of lymphoma, while the absence of LGB nearly excludes this diagnosis. No trends were observed with the other criteria which were tested. LGB in aspiration cytology smears from malignant tumors thus represent a useful tool to distinguish high-grade NHL from carcinoma and sarcoma.

Lymphosarcoma with plasmacytoid differentiation in a scarlet macaw (Ara macao).

A lymphosarcoma in a scarlet macaw (Ara macao) affecting periocular structures is described. Microscopically and ultrastructurally, many of the lymphoid cells had plasmacytoid features. Polymerase chain reaction amplification failed to detect exogenous avian retrovirus RAV-1 in the neoplastic mass.

[Primary non-Hodgkin's lymphoma of the mandible: a description of a clinical case and review of literature]. / Linfoma non Hodgkin primitivo della mandibola: descrizione di un caso clinico e revisione della letteratura.

The authors present a rare case of primary non-Hodgkin lymphoma (NHL) of the mandible in an 81-year old woman. The location of this NHL caused problems in making a differential diagnosis between periodontal and tumoral disease as they have similar symptoms (i.e. dental pain, swelling, ulceration and radiologically detected rarefaction). The present work emphasizes how important correct diagnosis and staging of the primary NHL are to good therapy. The patient was treated with a combination of chemotherapy and radiotherapy and is alive and disease-free 12 months after treatment.

Rosette-forming non-Hodgkin's lymphomas.

Homer Wright rosettes, typically found in neuroblastomas and consisting of neoplastic cells surrounding an eosinophilic fibrillary centre without a lumen, have been considered as an important finding in the differential diagnosis of small round cell tumours. Rosettes in a neoplasm involving lymph nodes or bone marrow traditionally excluded a diagnosis of malignant lymphoma. In this report, we describe three cases of malignant lymphoma (two small lymphocytic and one diffuse large cell) with pronounced rosette formation. One of the two cases of small lymphocytic lymphoma was observed in the bone marrow, the other small lymphocytic lymphoma and the large cell lymphoma were in lymph nodes. The rosettes consisted of neoplastic lymphoid cells, often with participation of reactive macrophages, and ultrastructurally they had a central mass of interdigitating fibrillary cytoplasmic projections. Two cases were of B-cell lineage and one was of T-cell lineage. To the best of our knowledge, this is the first report of T-cell lymphoma with rosettes. Based on these findings, it is suggested that non-Hodgkin's lymphoma be included in the differential diagnosis of rosette-forming round cell neoplasms.

Use of CD23 (BU38) on paraffin sections in the diagnosis of small lymphocytic lymphoma and mantle cell lymphoma.

The CD23 antigen is a low-affinity immunoglubulin E receptor that is expressed during B-cell activation. Recently, it has been shown to be of diagnostic utility in distinguishing between small lymphocytic lymphoma (SLL) and mantle cell lymphoma (MCL), two entities that can have similar morphologic and immunophenotypic features. Such studies, however, generally required viable cells in cell suspension or cryostat sections for detection of CD23. We evaluated staining for the CD23 antigen in paraffin sections, using BU38, an antibody that detects a fixation-resistant epitope of the antigen. We analyzed 44 SLLs, 3 lymphoplasmacytoid lymphomas, and 39 MCLs. Staining was performed on formalin- or B5-fixed paraffin-embedded tissue sections using L26 (CD20), CD3, Leu22 (CD43), and BU38 (CD23) antibodies. All of the cases were of B-cell phenotype (CD20+), and 42/44 SLLs, 3/3 lymphoplasmacytoid lymphomas, and 33/39 MCLs coexpressed the CD43 antigen. CD23 was positive in 41 (93%) of 44 SLLs. The majority of neoplastic cells (75% or more) stained positively, with a membranous pattern of staining. The staining was moderate in intensity and easily interpreted. Only 1/39 MCLs and 1/3 lymphoplasmacytoid lymphomas were CD23 positive. CD23-positive follicular dendritic cells were, however, present in all of the MCLs, either in residual follicles or in large, disordered meshworks. These results demonstrate that the BU38 antibody can detect CD23 on the cells of SLLs in paraffin sections and that this antibody can have diagnostic utility in routine diagnosis.

The ultrastructure of mantle cell lymphoma and other B-cell disorders with translocation t(11;14)(q13;q32).

We conducted an ultrastructural study in 22 cases of B-lymphoproliferative disorders in leukaemic phase bearing the t(11;14) translocation. The features of peripheral blood leukaemic cells in nine cases of mantle cell lymphoma (MCL) were compared to those diagnosed as B-prolymphocytic leukaemia (B-PLL) (five cases), splenic lymphoma with villous lymphocytes (SLVL) (four cases), lymphoplasmocytic lymphoma (LPL) (one case), chronic lymphocytic leukaemia with > 10% prolymphocytes (CLL/ PL) (one case) and unclassified B-non Hodgkin's lymphoma (B-NHL) (two cases). The ultrastructural characteristics were also compared to those present in B-NHL without t(11;14), including cases of follicular centre lymphoma (FCL). This study shows that MCL has distinct ultrastructural features including a cleaved or indented nucleus with an even heterochromatin distribution, an absent or inconspicuous nucleolus, low N/C ratio, abundant mitochondria, a well developed Golgi zone, profiles of endoplasmic reticulum and centrioles. This pattern clearly differs from that found in FCL cells. The nuclear pattern of MCL cells also differed from the cells in the other disorders with t(11;14), but shared an organelle-rich cytoplasm, and features which were not apparent in cases without t(11;14). The cytoplasmic changes observed in cells bearing t(11;14) suggest increased cellular activity which may relate to the chromosome translocation and the resulting over-expression of bcl-1.

Histology, immunohistochemistry, and electron microscopy of small round cell tumors of bone.

Small round cell tumors (SRCTs) of the bone make up a family of primary bone sarcomas with morphologically, biologically, and clinically specific features. Among them, Ewing's sarcoma (ES) is the most common entity, but several varieties such as atypical ES, large cell ES, and ES with neuroectodermal differentiation (peripheral primitive neuroectodermal tumor of the bone or neuroepithelioma of the bone) have been identified recently. Histology and electron microscopy together with the variable expression of several epitopes (as shown by immunohistochemistry, mainly HBA/71 [Mic2 antigen]) provide the basis for characterizing the group within the context of neuroectodermal-derived neoplasms. A number of other ES-like tumors with small round cells, mimicking those previously described, have been characterized; Askin's tumor of the thoracopulmonary region will be considered as an ES similar to those already described, but within a particularly anatomic location. On the other hand, the presence of an endothelial appearance within a poorly differentiated neoplasm may be present in some ES-like SRCTs (atypical ES with endothelial features). The differential diagnosis with other sarcomas defined by small round to spindle cell contours might prove difficult. Particular attention must be paid to small cell osteosarcoma and mesenchymal chondrosarcoma. Likewise, "primitive sarcoma of bone" is considered in this study because it is a very rare neoplasm differing from the formerly discussed types; its pluripotentiality provides this tumor a blastemic character and a multiphenotypic expression. Malignant non-Hodgkin's lymphoma is an unusual presentation when primary to the bone, previous to any other anatomic location. Several subtypes have been considered within a histology that encompasses that seen in lymph nodes.

Laryngeal lymphoma derived from mucosa-associated lymphoid tissue.

Extranodal lymphomas account for as many as 40% of non-Hodgkin's lymphomas, and most arise in the gastrointestinal tract, but other mucosal organs may be involved, especially the upper aerodigestive tract. Low-grade B-cell lymphomas arising in the gastrointestinal tract and other mucosae have been found to recapitulate the structure and cytologic features of mucosa-associated lymphoid tissue (MALT). Histologically low-grade MALT lymphomas are characterized by centrocyte-like B-cells with a phenotype similar to that of so-called marginal zone B-cells. Tumors evolving from MALT are generally rare among lymphomas of the upper aerodigestive tract, but a few cases of laryngeal lymphomas derived from MALT have been reported. Primary MALT lymphoma of the larynx should always be considered in tumors with histopathologic features of low-grade B-cell lymphoma, or so-called pseudolymphoma.

Plasma cells with iron inclusions in two non-alcoholic Chinese women.

Plasma cells with iron granules are rare, especially among non-alcoholic individuals. We report two teetotaller Chinese women with nasopharyngeal carcinoma and non-Hodgkin's lymphoma, whose bone marrow studies revealed plasma cells with inclusions morphologically compatible with iron granules. The iron nature of the granules was confirmed by elemental analysis. The clinical significance and the exact mechanism of formation of these iron inclusions in plasma cells remain unknown.