1,721,255 research outputs found
Atypical lipomatous tumor: molecular characterization
No full textPurpose of review Atypical lipomatous tumors/well-differentiated liposarcomas (ALT/WDLs) are one of the more frequent mesenchymal neoplasms and are characterized by specific chromosome aberrations: supernumerary chromosome or giant marker chromosome or both. Extra copies of known oncogenes such as MDM2, CDK4, SAS, HMGA2 and others are present in this abnormal genetic material. Recent findings In the past few years, several papers have further dissected the genetic alterations present in these tumors, allowing the identification of new potential oncogenes. Summary ALT/WDLs represent therefore an interesting model for assessing the potential role of these oncogenes, not only in the pathogenesis, but also as a therapeutic target. ZR 0 ZS 0 Z8 1 ZB
Identification of calretinin and the alternatively spliced form calretinin-22k in primary pleural mesotheliomas and in their metastases
No full textBackground: Antibodies against calretinin represent an established, powerful and reliable immunohistochemical marker in the differential diagnosis between mesothelioma and adenocarcinomas. However, in studies published so far, the exact molecular identity of the immunoreactive protein(s) detected in mesothelioma sections has not yet been determined. Materials and Methods: Tissue biopsies from ten mesothelioma samples,, primary and metastatic, were analyzed by Western blot analysis and reverse transcriptase-polymerase chain reaction (RT-PCR), in addition to immunohistochemical staining. Results: Besides the selective positive immunoreaction in all 10 samples, calretinin was identified by Western blot analysis and by identification of its mRNA by RT-PCR. In addition, we identified the alternatively spliced form calretinin-22k and the corresponding mRNA, previously detected only in neoplastic cells in colon carcinomas and derived cell lines. Conclusion: Our findings demonstrate that the immunoreactivity observed in the mesotheliomas and their metastases investigated in this report is due to the concomitant presence of calretinin and the alternatively spliced form calretinin-22k
New transcription factors in diagnostic hematopathology
No full textThe transcription factors (TFs) that controls the intricate machinery of multistep differentiation and activation programs of the lymphoid system, represent a complex array of proteins, whose identification and function has only in part been completed. TFs are usually expressed during specific differentiation or activation cellular programs, making them interesting tools in diagnostic immunohistochemistry. In fact, the specificity of some of these TFs for lineage or activation/differentiation passages or their abnormal expression in specific disease entity, represents a feature that has been exploited in diagnostic/prognostic immunohistochemistry. Bcl-6 was the prototype of this class of markers. Currently.. the expanding knowledge of the TFs involved in the differentiation programs and in the activation processes of T-lymphocyte and B-lymphocyte in normal and neoplastic conditions and the availability of antibodies able to efficiently recognize these TFs in histologic material, represent a powerful tool in diagnostic hematopathology. In this review we will consider the basic biologic aspects and the applications in hematopathology of some of the lymphocyte-related TFs, including Pax5/BSAB, MUM1/IRF4, BOB1, Oct-2, T-bet, and FOXP3. This field is rapidly evolving, as witnessed by the ongoing growing number of novel TFs with possible diagnostic applications appearing in the literature.The transcription factors (TFs) that controls the intricate machinery of multistep differentiation and activation programs of the lymphoid system, represent a complex array of proteins, whose identification and function has only in part been completed. TFs are usually expressed during specific differentiation or activation cellular programs, making them interesting tools in diagnostic immunohistochemistry. In fact, the specificity of some of these TFs for lineage or activation/differentiation passages or their abnormal expression in specific disease entity, represents a feature that has been exploited in diagnostic/prognostic immunohistochemistry. Bcl-6 was the prototype of this class of markers. Currently.. the expanding knowledge of the TFs involved in the differentiation programs and in the activation processes of T-lymphocyte and B-lymphocyte in normal and neoplastic conditions and the availability of antibodies able to efficiently recognize these TFs in histologic material, represent a powerful tool in diagnostic hematopathology. In this review we will consider the basic biologic aspects and the applications in hematopathology of some of the lymphocyte-related TFs, including Pax5/BSAB, MUM1/IRF4, BOB1, Oct-2, T-bet, and FOXP3. This field is rapidly evolving, as witnessed by the ongoing growing number of novel TFs with possible diagnostic applications appearing in the literature. Z8 0 ZR 0 ZS 0 ZB 1
Immunocytochemical localization of progesterone receptors in endocrine cells of the human pancreas.
No full textChlamydial infection: the link with ocular adnexal lymphomas
No full textChlamydiae are obligate intracellular bacteria that grow in eukaryotic cells and cause a wide spectrum of diseases. They can establish persistent infections, are mitogenic in vitro, promote polyclonal cell proliferation in vivo and induce resistance to apoptosis in infected cells-properties that might contribute to tumorigenesis. In fact, Chlamydophila psittaci (Cp) has been linked to the development and maintenance of ocular adnexal marginal zone B-cell lymphoma (OAMZL). In this indolent malignancy, Cp is transported by monocytes and macrophages and causes both local and systemic infection. Cp elementary bodies are viable and infectious in the conjunctiva and peripheral blood of patients with OAMZL. Bacterial eradication with antibiotic therapy is often followed by lymphoma regression. Despite recent advances in the understanding of this bacterium-lymphoma association, several questions remain unanswered. For instance, prevalence variations among different geographical areas and related diagnostic and therapeutic implications remain a major investigational issue. We will focus on clinical and therapeutic implications of chlamydial infections in patients with lymphomas and summarize the current knowledge on the association between Cp infection and OAMZL. Available data on the epidemiology, biology and pathogenesis of this association are analyzed and new investigative and clinical approaches are discussed
Chronic lymphocytic leukemia: the pathologist's view of lymph node microenvironment
No full textChronic lymphocytic leukemia (CLL), an indolent B-cell malignancy frequently diagnosed in the elderly, is characterized by the relentless accumulation of CD5(+) monoclonal B cells that proliferate in the appropriate tissue microenvironments. Despite many advances achieved by molecular and functional studies, our knowledge of the reciprocal relationship between the CLL cell and its microenvironment at the tissue level is still largely incomplete. In this review we present the relevant current information on the tissue microenvironmental features of CLL, focusing on the events that appear to occur in the lymph node. Special attention is devoted to analyzing the properties of both neoplastic and nonneoplastic bystander cells within proliferation centers, the mysterious structures that likely represent the actual proliferative compartment. (C) 2011 Elsevier Inc. All rights reserved.Chronic lymphocytic leukemia (CLL), an indolent B-cell malignancy frequently diagnosed in the elderly, is characterized by the relentless accumulation of CD5(+) monoclonal B cells that proliferate in the appropriate tissue microenvironments. Despite many advances achieved by molecular and functional studies, our knowledge of the reciprocal relationship between the CLL cell and its microenvironment at the tissue level is still largely incomplete. In this review we present the relevant current information on the tissue microenvironmental features of CLL, focusing on the events that appear to occur in the lymph node. Special attention is devoted to analyzing the properties of both neoplastic and nonneoplastic bystander cells within proliferation centers, the mysterious structures that likely represent the actual proliferative compartment. (C) 2011 Elsevier Inc. All rights reserved. Z8 0 ZR 0 ZS 0 ZB 10"Chronic lymphocytic leukemia (CLL), an indolent B-cell malignancy frequently diagnosed in the elderly, is characterized by the relentless accumulation of CD5+ monoclonal B cells that proliferate in the appropriate tissue microenvironments. Despite many advances achieved by molecular and functional studies, our knowledge of the reciprocal relationship between the CLL cell and its microenvironment at the tissue level is still largely incomplete. In this review we present the relevant current information on the tissue microenvironmental features of CLL, focusing on the events that appear to occur in the lymph node. Special attention is devoted to analyzing the properties of both neoplastic and nonneoplastic bystander cells within proliferation centers, the mysterious structures that likely represent the actual proliferative compartment.
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