Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Australian Leukaemia Study Group myeloma study (MM1) aimed to determine the prognostic significance of clinical and immunophenotypic markers in patients with multiple myeloma. All patients were treated with standard dose melphalan and prednisone. Seventy-four patients were entered and the median survival was 27 months. Serum beta 2-microglobulin (beta 2M) and albumin levels were the only significant clinical factors influencing survival (p = 0.007 and p = 0.008, respectively). Patients with raised levels of CD38+ lymphocytes at presentation had a significantly shorter survival than patients with normal levels (p = 0.01, logrank test, median 19 months vs 33 months). CD38 antigen expression was independent of beta 2M but patients with raised levels of CD38 had significantly lower levels of albumin than patients with normal levels (p = 0.001) which may explain their poorer survival. Salmon and Durie stage was not associated with antigen expression. No other B-cell antigens (CD10, CD19, CD20, CD21, CD22, CD23, FMC1 or FMC7) or plasma cell antigens tested (PCA-1) were found to be associated with prognosis. Patients who achieved plateau phase had a better prognosis than those who did not (p = 0.04 in a landmark analysis). Patients who achieved plateau phase following an objective response appeared to have a better prognosis than those who were in plateau phase at presentation (p = 0.09 in a landmark analysis). Light chain isotype suppression (LCIS) was not associated with a significant survival advantage and did not correlate with any known prognostic indicator.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Peripheral blood lymphocyte surface antigen expression and prognosis in myeloma: Australian Leukaemia Study Group Study. 795 Sep 19

Regulation of the expression of major histocompatibility complex (MHC) class I heavy chains not associated with beta 2-microglobulin (beta 2m) on freshly isolated and in vitro cultured human B and T leukemia cells was analyzed. These beta 2m-free class I heavy chains originate from surface beta 2m-associated MHC class I molecules and are expressed as integral membrane glycoproteins on activated, but not resting, cells. We found that the levels of beta 2m-free class I heavy chains can be regulated by proteolytic cleavage and release into the medium of soluble molecules containing the extracellular domains. The release is mediated by a Zn(2+)-dependent, membrane-bound metalloprotease that does not cleave HLA-DR, CD4, and CD71 surface receptors and can be activated by phorbol myristate acetate. Specific cleavage by the metalloprotease occurs at a site close to the papain cleavage site in the alpha 3 domain of class I heavy chains. This site is not accessible to the metalloprotease in beta 2m-associated MHC class I molecules. The dissociation of beta 2m-associated MHC class I molecules and subsequent cleavage of beta 2m-free class I heavy chains may be partially responsible for controlling the levels of MHC class I molecules on the surface of activated cells.
 ...
PMID:Soluble beta 2-microglobulin-free class I heavy chains are released from the surface of activated and leukemia cells by a metalloprotease. 812 26

Murine leukemia virus infection serves as a model for noninflammatory degeneration of the central nervous system (CNS). During the course of infection with either of the molecularly cloned viruses pNE-8 or ts-1, we observed that ts-1 spread twice as rapidly as pNE-8, and ascended higher in the neuraxis. Endothelial cells were infected first, followed by oligodendrocytes and neurons, while astrocytes containing glial fibrillary acidic protein were not infected. Additionally, ts-1 also infected macrophages/microglia. Major histocompatibility complex (MHC) class I beta 2-microglobulin expression was minimal in pNE-8 infected mice, while it was elevated in endothelial cells of early ts-1 lesions, and in macrophages/microglia during later stages. Occasional infected cells expressed beta 2-microglobulin while rare endothelial and parenchymal cells expressed MHC class II in both viral infections. Limited intra-CNS MHC expression may be one of the mechanisms of viral persistence and will present a barrier to developing immunotherapy for CNS retroviral infections. The few mice that escaped lethal infection had higher serum titers of neutralizing antibodies and showed no neuropathologic changes or detectable virus in the CNS. Higher titers of neutralizing antibodies may protect the CNS from infection.
 ...
PMID:Expression of major histocompatibility complex antigens and serum neutralizing antibody in murine retroviral encephalitis. 838 32

Resistance to multiple chemotherapeutic agents is related to the production of P-glycoprotein, a transmembrane drug efflux pump that is encoded by the multidrug resistance gene (MDR1). To detect low-level or heterogenous expression of the MDR1 gene in acute leukemia, we have developed sensitive, specific and semi-quantitative protocols for measuring levels of MDR1 mRNA, based on the polymerase chain reaction. Using this assay, we screened blasts from 20 patients with untreated adult acute leukemia for evidence of MDR1 gene expression. The level of MDR1 mRNA was normalized to beta 2-microglobulin mRNA and was defined by reference to the highly resistant trimetrexate-selected leukemia cells MOLT-3/TMQ200 (1.80). MDR1 mRNA was observed in 14 out of 20 patients. Higher MDR1 mRNAs were observed in three patients with phenotypes of undifferentiated or minimally differentiated nonlymphocytic acute leukemia, as compared with other types of acute leukemia (0.98 vs. 0.25). In contrast, lower MDR1 mRNAs were found in five patients with acute promyelocytic leukemia, as compared with other types of acute leukemia (0.08 vs. 0.45). These findings suggest that MDR1 gene expression is correlated with the leucocyte differentiation stage of leukemia. MDR1 gene expression may, in part, explain the responsiveness to chemotherapy in these distinct subtypes of acute leukemia.
 ...
PMID:MDR1 (multidrug resistance) gene expression in adult acute leukemia: correlations with blast phenotype. 847 61

HLA class I antigens of the human major histocompatibility complex play an important role in immune response. These molecules present foreign antigenic peptides to cytotoxic T lymphocytes and thereby play a role in the immune surveillance of cells infected with virus or other intracellular pathogens or altered by malignant transformation. A marked deficiency or lack of expression of these antigens has been reported in a variety of human neoplasms. In the present study, we examined the expression of class I alpha chain, beta 2-microglobulin, TAP (TAP1 and TAP2) and LMP (LMP2 and LMP7) genes in a number of human tumor cell lines including small-cell lung carcinoma, hepatocellular carcinoma, colon adenocarcinoma and basophilic leukaemia. These cell lines were deficient in expression of both class I alpha chain and beta 2-microglobulin gene products. In addition, these cell lines lacked the products of MHC-encoded proteasome subunit LMP2 as well as the putative peptide transporter TAP1 genes. In contrast, TAP2 and LMP7 genes were expressed in these cell lines. Treatment of cells with gamma-IFN markedly enhanced the expression of class I alpha chain, beta 2-microglobulin, TAP1 and LMP2 genes with a concomitant increase in cell-surface expression of class I molecules. The upregulation of TAP1 and LMP2 expression is associated with increased class I expression, suggesting that endogenous antigens, e.g. tumor antigens, could be presented by class I molecules following treatment of tumor cells with gamma-IFN.
 ...
PMID:Markedly decreased expression of TAP1 and LMP2 genes in HLA class I-deficient human tumor cell lines. 880 12

Plasma cell dyscrasias form a heterogeneous group of diseases characterized by the expansion of the number of monoclonal bone marrow plasma cells that produce monoclonal immunoglobulins. Sensitive electrophoretic methods have shown that the incidence of these diseases is as high as 5% in adult individuals. Thus, the majority of cases should be considered to be a normal phenomenon. A few transform into neoplastic diseases, plasma cells becoming responsible for lytic bone lesions, the hallmark of MM. The distinction of benign and malignant forms is frequently difficult at presentation. We can easily recognize solitary myeloma, overt myeloma and plasma cell leukaemia, which require immediate chemotherapy. Therapy could be safely withheld in all the remaining forms, which require only follow-up. Thus, we suggest that plasma cell dyscrasias should be classified simply into two main groups according to the need of immediate chemotherapy. The appearance of new bone lesions and the increase of the M-component level remain the only two criteria that define malignant transformation. Several clinical and laboratory prognostic parameters indicate the risk of transformation, and hence how close the follow-up of the patient should be. Parameters related to the expansion of the plasma cell clone (percentage of bone marrow plasma cells, M-component level, lytic bone lesions and beta 2-microglobulin) are not always very low and very high in the benign and malignant forms, respectively, and frequently overlap in patients with intermediate plasma cell expansions. On the contrary, all parameters related to the intrinsic malignancy of the plasma cells (plasma cell LI, Karyotypic abnormalities and molecular alterations) have, by definition, to be normal in the benign forms. MRI is a new tool that may, early on, reveal lytic bone lesions undetectable by conventional radiography.
 ...
PMID:Plasma cell dyscrasias: classification, clinical and laboratory characteristics, and differential diagnosis. 884 68

Adult T-cell leukemia/lymphoma (ATL) and human T-cell lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) are associated with differing patterns of immune dysfunction. Biomarkers of immune activation may correlate with perturbations of immune function associated with these diseases. We conducted a pilot cross-sectional study to assess four candidate biomarkers of immune activation. beta 2-microglobulin, neopterin, tryptophan, and kynurenine levels were assayed in stored sera from asymptomatic, human T-cell leukemia virus type I (HTL V-I)-seronegative (HTLV-I-) and HTLV-I-seropositive (HTLV-I+) individuals, and ATL and HAM/TSP patients previously enrolled in seroepidemiological studies in Jamaica. Mean levels of beta 2-microglobulin, neopterin, and kynurenine were significantly elevated among ATL patients compared to the other study groups. Mean tryptophan levels were significantly lower among ATL and HAM/TSP patients than HTLV-I- and HTLV-I+ groups. No significant differences in biomarkers were found between the HTLV-I- and HTLV-I+ groups. Among HAM/TSP patients, a significant association was found between elevated neopterin levels and symptoms of less than 4 years duration. In Cox proportional hazards regression modeling, neopterin and tryptophan were found to be independent predictors of survival among ATL patients. This study demonstrates a differential pattern of biomarkers of immune activation among ATL and HAM/TSP patients compared to HTLV-I- and HTLV-I+ individuals. Neopterin and tryptophan may be useful clinical indicators of disease severity and prognosis among HAM/TSP and ATL patients.
 ...
PMID:Differential patterns of serum biomarkers of immune activation in human T-cell lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis, and adult T-cell leukemia/lymphoma. 887 61

As the clinical manifestations of adult T-cell leukemia (ATL) can be quite diverse, useful indicators for the therapy and prognosis are required for the disease. In this review, the clinical and biological significance of serum tumor markers at diagnosis in ATL patients is described. Serum lactic dehydrogenase (S-LDH), serum thymidine kinase (S-TK) and serum parathyroid hormone-related protein (S-PTHrP) at diagnosis of ATL showed a correlation with among leukocyte count, absolute number of abnormal lymphocytes with polymorphic nuclei, platelet count, serum calcium and the length of survival after the initial diagnosis. Serum beta 2-microglobulin (S-beta 2M) correlated with age, platelet count and survival. A statistical correlation existed between these four serum tumor markers. Other serum tumor markers such as immunosuppressive acidic protein (S-IAP), ferritin (S-Ft) and tissue polypeptide antigen (S-TPA) showed no correlation with clinical and histological data in ATL patients.
 ...
PMID:Clinical and biological significance of serum tumor markers in adult T-cell leukemia. 888 54

After many years of nosologic errance, plasma cell lymphoproliferative disorders are now firmly classified as belonging to the lymphoma family. Their characteristic biological and clinical course starts from the localized form of plasmacytoma, progressing to the more diffuse benign gammopathy, then the premalignant conditions like indolent (IM) or smouldering (SM) myeloma, and ending at the multiple myeloma (MM) stage. During and before this multistep development, genetic and environmental factors appear to be involved and spontaneous regressions may even occur. However, when MM is diagnosed, the outcome is invariably fatal despite conventional radiotherapy and chemotherapy. Prognostic factors like G-reactive protein, the plasma cell labeling index, and beta 2-microglobulin are extremely useful not only for determining the aggressivity of the abnormal clone but also for predicting the transformation from a benign state to a definitive malignant condition. Standard single-agent chemotherapy with melphalan and multidrug combinations can significantly prolong survival, but no cure has yet been achieved. High-dose chemotherapy with stem cell support can decrease tumor burden to an undetectable level and, compared with conventional approaches, has recently proved to increase response rates, the symptom-free interval, and survival. Moreover, interferon alfa is also able to prolong the responding interval, but this has yet to be translated into a survival advantage. These new more aggressive therapies are reminiscent of the early days of leukemia treatment and should now be offered to patients in controlled trials on the basis of comorbidities rather than age or some discriminating economic factors.
 ...
PMID:Multiple myeloma: clinical evaluation of plasma cell lymphoproliferative disorders and initial management. 912 44

Serum soluble interleukin-6 receptor (sIL-6R) concentrations were measured in 50 patients with plasma cell dyscrasias using a commercially available immunoenzymatic assay kit. There were 40 patients with multiple myeloma (MM), 5 patients with monoclonal gammopathy of undetermined significance (MGUS), 3 patients with solitary plasmacytoma (SPC), 1 patient with chronic myelogenous leukaemia and multiple myeloma (CML/MM), and 1 patient with plasma cell leukaemia (PCL). We found that serum sIL-6R concentrations were higher in MM patients (62.53 +/- 38.85 ng/ml) than in 20 normal volunteers studied (36.75 +/- 13.79 ng/ml) (p < 0.01). The cut-off value of 65 ng/ml seen in 2 of our controls was arbitrarily taken as the upper limit of the control range for serum sIL-6R; according to this criterion, 14 patients with MM (35%), 1 patient with SPC, the unique patient with CML + MM, and the unique patient with PCL had elevated concentrations of the receptor. Patients with MGUS had normal sIL-6R values. In MM patients, serum sIL-6R levels correlated with the clinical phase of the disease: they were elevated in patients with early or late active disease and ranged within normal limits in patients with plateau-phase disease (p < 0.001). Thirteen of 27 patients with active MM had elevated serum sIL-6R values, i.e. 48.1%, but only 1 out of 13 patients with disease in the plateau phase, i.e. 7.7% (p < 0.05). Furthermore, in the entire group of MM patients, serum sIL-6R levels correlated with the concentrations of serum beta 2-microglobulin, (p < 0.02), CRP (p < 0.01), ferritin (p < 0.01) and LDH (p < 0.01), while they did not correlate with disease stage, haemoglobin levels, proportion of marrow myeloma cells, the values of serum IL-6, the levels of serum albumin, or the grade of bone lesions. We conclude that elevated serum sIL-6R levels should be related to the growth of myeloma cells and suggest that serum sIL-6R concentrations may be used as an indicator of disease activity.
 ...
PMID:Serum levels of soluble IL-6 receptor in multiple myeloma as indicator of disease activity. 915 60


<< Previous 1 2 3 4 5 6 7 Next >>