Ta-Hsu Chou

Evaluation of two plasma fucosyltransferases as marker enzymes in non-Hodgkin's lymphoma.

Levels of two fucosyltransferases were measured in plasmas of patients with non‐Hodgkins lymphoma at different phases of the disease. The level of a GDP‐fucose: galactoside fucosyltransferase (EC 2.4.1.69) was found elevated in nonresponding patients and was correlated with estimated tumor burden. Enzyme levels in the normal range were found in patients in remission, maintained on chemotherapy, or unmaintained. The plasma level of a GDP‐fucose: N‐acetylglucosaminide fucosyltransferase (EC 2.4.1.68) was elevated in all individuals receiving drug therapy regardless of disease status, but returned to normal levels during unmaintained remissions.

Studies on sialyltransferase isoenzymes in plasma of patients with breast cancer

Abstract An elevated level of sialytransferase was often found in plasma of patients with breast cancer, but the extent of this elevation was highly variable, as was the enzyme level in plasma of normal donors. Electrofocusing studies indicated the presence of sialyltransferases, focusing at pH 5.2 and 5.6 , in all plasmas examined. Elevated enzyme activity in plasma of normal donors was associated with appearance of an ‘inflammatory response’ isoenzyme with pI = 7.5 . In plasma of the individuals with untreated primary or recurrent breast cancer, we found a new sialyltransferase isoenzyme with pI = 4.7 . This isoenzyme was not detected in plasma of patients with benign breast disease.

Porphyrin localizing phenomena.

The use of the porphyrin product HPD1 for tumor localization (1,2) and therapy (2–5) has been described. One report on an analysis of HPD appeared in 1980 (6) and other such reports are contained in this book. In order to characterize the events leading to tumor localization by HPD, it will be necessary to delineate active components in the product, the nature of any porphyrin transformations associated with the localization process and loci of binding of localized fluorescent porphyrins within the tumor cell.

Levels of Two Plasma Fucosyltransferases as an Index of Disease Status in Patients with Acute Myelogenous Leukemia

Publisher Summary It has been found that patients with acute myelogenous leukemias have two plasma enzymes as pertinent markers of marrow status. The level of a GDP-fucose:galactoside fucosyltransferase was found correlated with the proportion of marrow blasts, while the level of a GDP-fucose:N-acetylglucosaminide fucosyltransferase was elevated during regeneration of a normal marrow population following drug therapy. GDP-fucose:galactoside fucosyltransferase (Fuc→Gal) activity was measured with GDP-[14C] fucose and an asialo-fetuin (aSF) acceptor. The assay method for these two enzymes has been described and utilizes the preferential inhibition of the (Fuc→Gal) enzyme. During drug-induced remissions, the level of plasma enzyme activity fell to control levels. Although the plasma level of the (Fuc→GlcNAc) fucosyltransferase was not elevated above control in untreated or nonresponding patients, this level rose substantially during drug induced remissions. This chapter also explores the results of another study that was carried out and reported a fall in fucosyltransferase activity in plasma of patients with leukemia. This study was carried out with a low mol. wt. fucose acceptor.