Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019829 (Hodgkin's disease)
 30,247 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Enzyme activity measurements are of great relevance to the classification and biochemical characterization of the various types of leukemias, but they have been much less studied in solid lymphoid tumors. The authors report investigations in human lymphomas. The levels of the following enzymes were determined: terminal deoxynucleotidyl transferase (TdT), deoxyribonucleic acid polymerase alpha (DP alpha), adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), thymidine and uridine kinases (TK and UK, respectively), and thymidine phosphorylase (ThPh). Moreover, cytochemical investigations were done in the group of Burkitt's lymphoma (BL) and lymphoblastic lymphoma (LL), and ultrastructural studies were performed in seven of the nine LL of this series. These results were obtained: (1) TdT (90 cases) was highly specific for LL; eight of nine LL were positive, and all other histologic types were negative; the only TdT-, acid esterase (AcE) positive, nonconvoluted LL was probably related to TdT- normal medullary thymocytes, and had an unfavorable clinical course with resistance to a vincristine-and-prednisone-including treatment; (2) ADA (61 cases) could distinguish clearly between the high levels of LL and the low levels found in any other group of lymphomas; among LL, the highest values were found in T-cell-derived neoplasias, and the lowest value in a periodic acid-Schiff (PAS) positive, acid phosphatase negative case that showed the presence of large nucleoli at the ultrastructural analysis, a finding that is unusual for LL and possibly related to a more immature differentiation stage; (3) PNP (39 cases) values alone were not clinically relevant, but together with ADA levels, a subset of T-LL with high ADA:PNP ratio could be selected among LL; (4) DP alpha (61 cases), and TK and UK (37 cases) were found in concentrations reflecting the malignancy of the non-Hodgkin's lymphoma, and were more elevated in the high-grade malignant lymphomas; (5) ThPh (34 cases) was always elevated in Hodgkin's disease, but low in Burkitt's lymphoma and LL; thus, they had a high TK:ThPh ratio that could be useful in predicting clinical response to thymidine treatment. The authors think that taken together, multiple enzyme determinations could be useful in the characterization of human lymphomas.
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PMID:Multienzymatic analyses of human malignant lymphomas. Correlation of enzymatic data with pathologic and ultrastructural findings in Burkitt's and lymphoblastic lymphomas. 642 36

Thymidine kinase (TK) isoenzymes and thymidine phosphorylase (TP) activities have been measured in peripheral mononuclear cells of patients with acute lymphoblastic and monoblastic leukaemia or B-chronic lymphocytic leukaemia, as well as in normal subjects, and also in lymph node cells from patients with non-Hodgkin's lymphoma, with Hodgkin's disease and with benign adenopathies. TK1 isoenzyme activity was highest in acute lymphoblastic leukaemia and in centroblastic lymphoma. Then in progressively decreasing order appeared the Hodgkin's disease values, the centroblastic centrocytic lymphoma values and the benign reactive lymph node cell values. When compared to normal blood mononuclear cells, TP was greatly decreased in acute lymphoblastic leukaemia and slightly but significantly decreased in chronic leukaemia. Monoblastic cells exhibited a unique enzyme pattern; moderately increased TK1 activity and high TP activity. Our results suggest that both enzymes are indicative of the maturation status of leukaemic cells from B lineage. They demonstrate that in lymph node cells, TK1 reflects the proliferative status of both malignant and non-malignant cells and that in monoblastic cells the synthesis of dTMP through de novo synthesis is favoured.
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PMID:Thymidine kinase and thymidine phosphorylase activities in various types of leukaemia and lymphoma. 653

The catabolic enzyme thymidine phosphorylase (TP) plays a crucial role in nucleic acid metabolism by regulating the availability of thymidine. Platelet-derived endothelial cell growth factor (PD-ECGF) is an angiogenic factor that was recently shown to be TP. The angiogenic properties of PD-ECGF/TP are attributable to a reduction of thymidine levels that results in a promotion of endothelial cell proliferation. Early studies showed a higher concentration of TP in macrophages than in parenchymal cells and in neoplastic than in nonneoplastic tissues. We examined the immunohistochemical expression of PD-ECGF/TP in reactive lymphoid tissues (lymph node and tonsil), as well as in a series of 20 cases of Hodgkin's disease and 31 cases of non-Hodgkin's lymphomas. Macrophages, sinus lining cells, and cells with dendritic morphology, of both follicular dendritic and interdigitating reticular cell type, presented a prominent nuclear and cytoplasmic positivity in reactive lymphoid tissue and in malignant lymphomas. Small lymphocytes and the neoplastic population were always negative, whereas endothelial staining was variable and showed no correlation to the type or grade of the lymphomas. In Hodgkin's disease (with the exception of the nodular lymphocyte predominance type) and some cases of high-grade non-Hodgkin's lymphomas, the positive dendritic cells formed a dense meshwork closely surrounding the neoplastic population. Our results suggest that the reported upregulation of PD-ECGF/TP activity in lymphoid malignancies is attributable to the nonneoplastic population, especially to cells of dendritic morphology.
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PMID:Platelet-derived endothelial cell growth factor/thymidine phosphorylase immunohistochemical expression in lymphoid tissue and lymphoid malignancies. 934 21