Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.5.1.18 (glutathione S-transferase)
 22,582 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

By using RNA slot-blot technique, the frequency and the degree of GST pi and mdr-1 gene coexpression were investigated in 23 AML patients, 9 ALL, 9 CLL and 11 cases of NHL in an attempt to study their clinical and prognostic relevance. GST pi and mdr-1 levels were expressed as arbitrary units (U) with respect to the negative controls (U = 0), MCF7 and HL60 sensitive cell lines, and the positive controls (U = 10), MCF7/DOXO and HL60/DNR resistant cell lines. The concomitant GST pi/mdr-1 gene overexpression showed a negative prognostic value in the set of newly diagnosed AML pts (10 cases), furthermore higher GST pi and mdr-1 mRNA levels were averagely detected in the relapsed/resistant ALL pts (4 cases), and in CLL (7 cases) and NHL (8 cases) heavily pretreated patients who were unresponsive to chemotherapy and with a disease progression. These preliminary data show that two different mechanisms of drug resistance can be coexpressed at the same time in those leukemias and lymphomas with a clinically unfavourable course.
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PMID:Evaluation of the clinical relevance of the anionic glutathione-s-transferase (GST pi) and multidrug resistance (mdr-1) gene coexpression in leukemias and lymphomas. 787 3

Among mechanisms potentially involved in resistance to alkylating agents and anthracyclines, the glutathione system has been extensively studied in vitro. We analyzed by immunohistochemistry the relation between glutathione s-transferase pi (GST-pi) expression in tumor cells and outcome in 69 cases of diffuse large B-cell NHL (DLBCL). GST-pi expression was considered as low when <50% of tumor cells were stained and high when >/=50% tumor cells were stained. Median follow-up was 58 months. GST-pi expression was correlated with the probability of achieving complete remission (CR). Patients with high GST-pi expression had a worse 5-year freedom from progression (FFP). High GST-pi expression was associated with a trend for lower survival. In the group of patients with International Prognostic Index (IPI) 0-1, low GST-pi expression was associated with a CR rate of 88%, a 5-year FFP of 76+/-20% and a 5-year survival of 78+/-16% compared to 36, 14+/-16 and 40+/-32%, respectively, in patients with a high GST-pi expression (P=0.002, P&<10(-5) and P=0.01, respectively). No correlation was found between GST-pi expression and lactico deshydrogenase serum level, age, Ann Arbor stage, performance status, and IPI index. Both GST-pi expression and the IPI index correlated with FFP. After incorporating IPI and GST-pi expression in a multivariate analysis for FFP, GST-p expression remained the only prognostic factor (P=0.003). Our findings suggest that GST-pi expression had strong prognostic significance in DLBCL, which appears to be independent of other prognostic parameters in those disorders.
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PMID:Prognostic value of GST-pi expression in diffuse large B-cell lymphomas. 1275 Jul 12

Rituximab is the first anti-cancer antibody approved by the FDA for the treatment of B-cell non-Hodgkin lymphoma (B-NHL), alone or in combination with chemotherapeutic drugs. Further, rituximab is now being examined in a variety of CD20+ neoplastic diseases as well as B-cell-induced autoimmune diseases. The clinical response to rituximab is significant, resulting not only in tumor regression but also prolongation of survival. However, a subset of patients does not initially respond to rituximab or develops resistance to its further treatment. Therefore, alternative therapies for these patients are strongly desired. Rituximab activity has been thought to be by antibody-dependent cellular cytotoxicity, complement-dependent cytotoxicity and apoptosis, and studies in model systems established the role of rituximab in cell signaling-induced perturbation of anti-apoptotic survival pathways, suggesting that the patients unresponsive to rituximab may be overcome with other CD20 antibodies with different activities. This study investigated eight novel murine antibodies directed against CD20 for their physical and biological properties in comparison with 2B8 and c2B8 (rituximab). These antibodies were derived by various antigenic and immunization procedures and selected for CD20 activity. Analysis of these antibodies revealed that they all bound to various B-cell lines and CD20-transfected CHO cells. Six of the eight antibodies shared similar variable-region amino acid sequences that were also shared by 2B8 while two monoclonal antibodies did not. Of them, 1K1791 has a distinct heavy chain and both 1K1791 and 1K1782 have distinct light chains. Not all of the antibodies inhibited cell growth and only two antibodies reacted with fixed GST-CD20 recombinant fusion protein. Noteworthy, 1K1791 was found to inhibit cell proliferation and also induced caspase-independent apoptosis in the absence of cross-linker. These findings identified new antibodies with properties and epitope specificities different from 2B8. The potential clinical application of such antibodies in the treatment of B-NHL and rituximab-resistant B-NHL is discussed.
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PMID:Characterization of novel murine anti-CD20 monoclonal antibodies and their comparison to 2B8 and c2B8 (rituximab). 1754 2

Metabolic pathway enzymes, such as Cytochrome P450 (CYP), glutathione S-transferase (GST), and N-acetyltransferases (NAT) are involved in activation and detoxification of environmental carcinogens as well as drug metabolism. We hypothesized that the genetic variations in such metabolic pathways may affect NHL prognosis and survival. Follow-up information of 496 female NHL incident cases diagnosed during 1996-2000 in Connecticut were abstracted from the Connecticut Tumor Registry in 2008; survival analyses were conducted by comparing the Kaplan-Meier curves, and hazard ratios (HR) were computed from the Cox Proportional Hazard models adjusting for demographic and tumor characteristics which were suggested by previous studies to be determinants of NHL survival. We identified six SNPs from four metabolism genes (CYP2E1, GSTP1, GSTT1, and NAT1) that were associated with NHL survival. Specifically, polymorphisms in GSTT1 were associated with follicular lymphoma survival; and polymorphisms in CYP2E1, GSTP1, and NAT1 were associated with survival of chronic lymphocytic leukemia/small lymphocytic lymphoma. Our study suggests that genetic polymorphisms in metabolic pathways may help improve the prediction of NHL survival and prognosis.
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PMID:Genetic polymorphisms in the metabolic pathway and non-Hodgkin lymphoma survival. 2002 44