Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Eight cases of acute myelogenous leukemia with (8; 21) translocation were reported. As recently reported, they showed following features: M2 morphology in FAB classification (all 8 patients), abnormal granulocyte maturation, i.e. large granules and pseudo Pelger-Huet forms (5), Auer rods (8), occasional eosinophilia (2), frequent loss of one sex chromosome (5), the low neutrophil alkaline phosphatase activity (5), and tumor formation (one). Both CD13 and CD33 antigens were expressed on smaller number of leukemic cells than the other AML (M2) cells, whereas CD34 and HLA-DR antigens were expressed on higher number of cells. Interestingly CD19 antigen was detected on a small to large population of tumor cells from four out of six patients. Despite the high remission rate, many of them relapsed within one year. More intensive postinduction and maintenance therapy should be considered for those patients.
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PMID:[Clinical and cytological features of acute myelogenous leukemia with 8; 21 chromosome translocation]. 192 Aug 38

The human progenitor cell antigen (CD34) is selectively expressed on hematopoietic progenitor cells in the bone marrow. In either cryostat sections of snap-frozen skin, or formalin-fixed paraffin-embedded sections of normal skin, anti-CD34 monoclonal antibody immunostained vascular endothelial cells and perivascular/interstitial dendritic cells, particularly in the reticular dermis. A distinctive population of perifollicular spindle-shaped cells in the midportion of the follicle (ie, bulge area), which is the site of the putative hair follicle stem cells, were CD34 positive, as were spindle-shaped cells in and around the eccrine glands accentuating their basement membrane zone. In patch/plaque--and tumor-stage acquired immunodeficiency syndrome-associated Kaposi's sarcoma lesions, CD34 expression was present on both the proliferating endothelial cells as well as the spindle-shaped stromal cells. CD34 positive endothelial cells and spindle-shaped stromal cells may play important participatory and supportive functions in both normal and diseased skin.
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PMID:The human progenitor cell antigen (CD34) is localized on endothelial cells, dermal dendritic cells, and perifollicular cells in formalin-fixed normal skin, and on proliferating endothelial cells and stromal spindle-shaped cells in Kaposi's sarcoma. 200 77

The ability to obtain large numbers of purified hematopoietic progenitors (HPC) will facilitate the understanding of elements that influence the growth and differentiation of bone marrow. Furthermore, HPC isolation will have direct application to autologous marrow transplantation (AMT) for malignancies as well as facilitate the transfer of genes in marrow cells for the correction of genetic disorders. The transplantation of HPC will help delineate the cells or factors responsible for graft rejection and graft-versus-host-disease. Or several techniques that have been utilized for the separation of HPC, only the avidin-biotin immunoadsorption (ABIA) method has been shown capable of separating the number of cells required for large animals and man. The application of this technique to AMT in man requires the identification of an antigen found predominantly on HPC in peripheral blood or marrow but not on malignant cells that could potentially contaminate bone marrow. Studies have demonstrated that the CD34 antigen is expressed by the majority of human marrow HPC measured in long-term marrow culture and is expressed on cells capable of autologous engraftment in lethally irradiated baboons. Although the CD34 antigen is not detectable by FACS analysis on peripheral blood cells, ABIA can enrich for such cells. The CD34 antigen is not detected on cells from patients with breast cancer or neuroblastoma thus allowing clinical studies to proceed. Preliminary results suggest that CD34(+)-enriched cells are depleted of tumor cells and are capable of autologous reconstitution in man.
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PMID:Positive selection of hematopoietic progenitors from marrow and peripheral blood for transplantation. 229 21

CD15 is expressed on a wide variety of tumor cells including myeloid leukemia, breast, colorectal, lung cancer cells. It is probable that the core proteins and lipids differ on the different cell types since there is marked variability in the binding of the mAb within and among the different cell types. Previously, there had only been a single mAb of the IgG class directed to CD15. The present study demonstrates the existence of one more IgG mAb (an IgG3). Unfortunately, a third mAb submitted as an IgG1, MA14, did not appear to be an IgG in our studies and a fourth mAb, MA9, submitted as an IgG1 did not have significant binding activity and also could not be confirmed as anti-CD15. An interesting finding was that all of the mAb could mediate complement-dependent cytotoxicity with rabbit serum. However, the two IgG3 mAb, MA63 (MCS-1) and MA88 (7C3), could not mediate lysis with human complement, while all of the IgM mAb could do so. It is not clear why this difference exists. CD15 is known to be expressed on mature myeloid cells in the hematopoietic lineage. The expression of CD15 on progenitor cells has been mapped by the indirect method of C'-dependent lysis and measurement of colony-forming cells. These studies have estimated that about 50% of normal CFU-GM express CD15. In the present workshop, we examined the expression of CD15 on a quantifiable cell population, the CD34 positive population.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Introduction: workshop summary of the CD15 monoclonal antibody panel from the Fifth International Workshop on Leukocyte Antigens. 748 22

Peptides of melanosomal proteins have recently been shown to be recognized in an HLA-restricted mode by specific cytolytic T lymphocytes in melanoma patients. Dendritic antigen-presenting cells (DC) are considered to be the most effective stimulators of T cell responses, and the use of these cells has therefore been proposed to generate therapeutic responses to tumor antigens in cancer patients. We, therefore, generated DC from peripheral blood of normal donors in the presence of granulocyte/macrophage colony-stimulating factor and interleukin-4. Flow cytometric analysis of the cells during a 2-week culture revealed a loss of CD14 and CD34 expression, a concomittent increase of CD1a, CD11a,b and c, CD44, CD45, CD54, HLA-class I and II, and intermediate levels of CD26, CD80 and CD86. Cultured DC stimulated proliferation of allogeneic T cells and induced a marked, up to 20-fold, stimulation of T cell proliferation after pulsing with tetanus toxoid. To achieve independence of already-identified antigenic peptides presented in HLA class I-restricted fashion, which limits the general applicability of such peptides for vaccination of melanoma patients, we tested whether DC are transfectable with eukaryotic expression plasmids. DC transfected with two reporter genes (CAT, beta-galactosidase) using a liposome-based transfection technique, exhibited only low levels of enzymatically active proteins, but were able to degrade rapidly intracellular proteins and to process peptides efficiently. Chloramphenicol acetyltransferase as well as tyrosinase mRNA were detectable after transfection by reverse-transcriptase-polymerase chain reaction, and enzyme activities became measurable. Furthermore, DC transfected with the tyrosinase gene were able to induce specific T cell activation in vitro, indicating appropriate peptide processing and presentation in DC after transfection. These data suggest new approaches to future tumor vaccination strategies.
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PMID:Dendritic cells generated from peripheral blood transfected with human tyrosinase induce specific T cell activation. 748 49

Recent studies have demonstrated that mature natural killer (NK) cells can be grown from human triple negative (TN; CD3-, CD4-, CD8-) thymocytes, suggesting that a common NK/T cell precursor exists within the thymus that can give rise to both NK cells and T cells under appropriate conditions. In the present study, we have investigated human fetal and postnatal thymus to determine whether NK cells and their precursors exist within this tissue and whether NK cells can be distinguished from T cell progenitors. Based on the surface expression of CD56 (an NK cell-associated antigen) and CD5 (a T cell-associated antigen), three phenotypically distinctive populations of TN thymocytes were identified. CD56+, CD5-; CD56-, CD5-, and CD56-, CD5+. The CD56+, CD5- population of TN thymocytes, although displaying a low cytolytic function against NK sensitive tumor cell targets, were similar in antigenic phenotype to fetal liver NK cells, gave rise to NK cell clones, and were unable to generate T cells in mouse fetal thymic organ cultures (mFTOC). This population of thymocytes represents a relatively mature population of lineage-committed NK cells. The CD56-, CD5- population of TN thymocytes were similar to thymic NK cells in antigenic phenotype and NK cell clonogenic potential. Clones derived from this population of TN thymocytes acquired CD56 surface expression and NK cell cytolytic function. CD56-, CD5- TN thymocytes thus contain a novel population of NK cell-committed precursors. The CD56-, CD5- population of TN thymocytes also contains a small percentage of CD34+ cells, which demonstrate no in vitro clonogenic potential, but possess T cell reconstituting capabilities in mFTOC. The majority of TN thymocytes do not express CD56, but coexpress CD34 and CD5. These CD56-, CD5+, CD34+ cells demonstrate no NK or T cell clonogenic potential, but are extremely efficient in repopulating mFTOC and differentiating into CD3+, CD4+, CD8+ T cells. The results of this investigation have identified NK cells and NK cell precursors in the human thymus and have shown that these cell types are unable to differentiate along the T cell lineage pathway. Thus, while a common NK/T cell progenitor likely exists, once committed to the NK cell lineage these cells no longer have the capacity to develop along the T cell developmental pathway.
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PMID:Human natural killer cell committed thymocytes and their relation to the T cell lineage. 750 51

Despite the wide variety of functions exhibited by mature peripheral blood cells, all are derived from a small pool (1-3%) of primitive precursor cells in the bone marrow (BM) that bear a unique surface glycoprotein, CD34. Isolated CD34+ cells are capable of reconstituting all hematopoietic lineages, both in experimental animals and in humans following intensive therapy. CD34+ cells capable of reconstituting hematopoiesis are also found at low frequency in peripheral blood (PB), a frequency which can be dramatically increased by combinations of chemotherapy and recombinant cytokines. In some cases, PB "stem cells" (PBSC) can be used to augment or even replace conventional BM autografts. The availability of CD34 antibodies has greatly aided the development of techniques for the enrichment of primitive progenitor cells, thus allowing studies of the hematopoietic potential of stem cells in vitro. Additionally, the use of CD34 antibodies for the "positive selection" of hematopoietic stem/progenitor cells from tumor-contaminated marrow may possibly represent an alternative "purging" strategy prior to transplantation. The availability of pure populations of the most primitive hematopoietic progenitor cells will also facilitate study of genetic manipulation as a practical therapeutic modality.
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PMID:CD34 antigen: molecular features and potential clinical applications. 750 57

This report is a case of epithelioid hemangioendothelioma presenting as multiple lytic lesions of the ilium with radiographic findings of diffuse, bilateral lung involvement and biopsy-proven scalp involvement. Histologically, the tumor within bone and skin exhibited cords and nests of plump, epithelioid-appearing cells exhibiting rudimentary vascular differentiation within a myxohyaline stroma. Aggressive histologic features were not present. Immunohistochemical reactivity for Factor VIII-related antigen, Q-bend 10 (CD34), and cytokeratin were demonstrated. Ultrastructural studies revealed abundant intermediate cytoplasmic filaments, pinocytotic vacuoles, and Weibel-Palade bodies. The concurrent bone, skin, and lung involvement, low-grade histologic type, and female sex of the patient aroused speculation about the role of hormones in the development and possible treatment of the tumor, but estrogen and progesterone receptors were not detected. Despite intense combination chemotherapy, the patient died of widely metastatic disease. This report demonstrates the aggressive potential of histologically low-grade epithelioid hemangioendothelioma and the need for a thorough evaluation for metastases.
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PMID:Epithelioid hemangioendothelioma with multiple site involvement. Literature review and observations. 750 96

Selection of CD34+ hematopoietic progenitor cells from autografts may be performed in multiple myeloma (MM) to minimize contamination with tumor cells. This approach is based on the assumption that the malignant cells do not express the CD34 antigen. Therefore, we first compared the CD34+/CD10+ and CD34+/CD19+ subpopulations from bone marrow (BM) and peripheral blood (PB) of fourteen MM patients and five normal controls. No difference between the respective early B cell subsets of both groups could be observed. Using tricolor flow cytometry, the CD19 expression on CD34+/CD10+ cells in BM was found to increase continuously from CD19- to CD19dim. In contrast, circulating CD34+/CD10+ cells did not coexpress the CD19 antigen. This population may contain myeloid progenitor cells or bipotential progenitor cells of the myeloid and lymphoid lineage as suggested by data obtained with fetal liver cells. Further functional studies are required. Enrichment of CD34+ cells with immunomagnetic beads was performed from BM of three MM patients and four normal donors. The CD34+ cells were selected with the HPCA-1 antibody and detached from the beads with chymopapain. Compared with the starting cell preparation, a 3.97 +/- 0.48 log (mean +/- SE) reduction of plasma cells could be achieved after CD34 selection. On morphological examination, 84% +/- 4% of the cells in the CD34+ fraction (MM) were immature blasts. The plating efficiency for hematopoietic colony forming cells was 9.7% +/- 2.8% in the CD34 selected fraction of the MM group, reflecting a 51-fold increase as compared with the starting population.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:CD34 selection for purging in multiple myeloma and analysis of CD34+ B cell precursors. 751 57

Sixty vascular tumors including 23 angiosarcomas, 300 nonvascular tumors, and selected normal tissues were immunohistochemically evaluated with antibodies to CD31, CD34, and von Willebrand factor (vWF), and monoclonal antibody BNH9, to test the sensitivity and specificity of these markers in the identification of endothelial cells and vascular tumors. Formaldehyde-fixed paraffin-embedded tissues and avidin biotin complex immunostaining were used. All markers labeled normal vascular and lymphatic endothelial cells approximately equally with the exception of CD34 which showed inconsistent expression within the lymphatics. In addition, antibody to CD31 reacted with platelets and megakaryocytes, CD34 with fibroblasts and aortic smooth muscle cells, and BNH9 with many epithelial cells including squamous and gastrointestinal epithelia. Antibody to vWF often showed significant stromal background staining which made the staining occasionally uninterpretable. Benign vascular tumors showed rather uniform staining with all antibodies. However, angiosarcomas were heterogeneous; CD31 was positive in 21/27, CD34 in 25/27 cases, BNH9 in 22/25, and vWF in 18/27 cases. Epithelioid hemangioendotheliomas showed consistent labeling for vWF, but were inconsistently labeled with antibodies to the other markers. Kaposi's sarcoma was positive for both CD31 and CD34. In addition, antibody to CD34 labeled the tumor cells in hemangiopericytoma, cerebellar hemangioblastoma, meningioma, most epithelioid sarcomas, dermatofibrosarcomas, and in a few other sarcomas. CD31, in turn, was not found in sarcomas other than angiosarcomas, but labeled weakly occasional carcinomas and mesotheliomas. Many adenocarcinomas and the glandular component of synovial sarcoma were BNH9 positive.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Endothelial cell markers CD31, CD34, and BNH9 antibody to H- and Y-antigens--evaluation of their specificity and sensitivity in the diagnosis of vascular tumors and comparison with von Willebrand factor. 751 18


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