Plasma sialyltransferase in patients with breast cancer

Gamma-glutamyltranspeptidase levels as an aid in the management of human cancer

Plasma gamma-glutamyltranspeptidase (GGTP) levels were measured in 435 cancer patients, 120 healthy controls, 15 patients with systemic lupus erythematosis, and 10 patients with rheumatoid arthritis. The mean GGTP activity of all cancer patients studied, with the exception of malignant lymphoma, was significantly elevated compared to control values. Several patient groups were retrospectively analyzed to determine whether GGTP levels correlated with clinical status. Patients who were disease-free had GGTP levels in the normal range, whereas patients with metastases had elevated levels. Serially increasing GGTP levels were associated with disease progression and death. Persons who remained free of disease had serial GGTP levels within the normal range. Furthermore, decreasing levels were associated with response to therapy. These results indicate that GGTP levels may have prognostic value in various human malignancies.

Serum protein-bound carbohydrates and small cell carcinoma of the lung. Correlations with extent of disease, tumor burden, survival, and clinical response categories

The levels for serum protein bound neutral carbohydrates (fucose, mannose, and galactose) were determined at specific intervals for 40 patients with small cell carcinoma of the lung and compared to the corresponding carcinoembryonic antigen (CEA) levels. In pretreatment samples, the frequency of elevation was 92.5% for fucose and 77.5% each for mannose and for galactose. CEA determined in these same samples was elevated (greater than 5 ng/ml) in 45.0%. One or more of the three carbohydrate levels were elevated in pretreatment serum of 95.0% of the patients. The individual frequency of elevation for each carbohydrate was significantly related to initial stage of disease (P less than 0.01). Median survival was significantly longer for patients based on a discriminant of less than 3 carbohydrates elevated in pretreatment samples (25 months) to all 3 elevated (11 months) with P = 0.0302. A single value, termed the biomarker index, was calculated to represent the summation of the individual carbohydrate levels per individual serum sample. The biomarker index was found to be directly correlated with extent of primary disease, number of metastic sites, tumor burden, and clinical response categories assessed at serial time points. For patients with both low Biomarker Index values and normal CEA levels in pretreatment samples, an initial rise in both determinations occurred frequently corresponding to partial or complete tumor response. The occurrence of such discordant results must be considered as a likely possibility for those patients with low or normal pretreatment biological marker levels and subsequent response to primary chemotherapy.

A feasibility study in the development of biological markers for ovarian cancer

As a primary feasibility study for the selection of biomarkers for more extended clinical evaluation, 17 potential biomarker candidates were measured in the body fluids of patients with ovarian carcinoma. For comparative purposes, patients were staged and separated into three groups: those considered completely free of disease, those with residual but minimal tumor, and those with advanced disease. Individual markers included plasma carcinoembryonic antigen, serum human chorionic gonadotrophin, urinary beta-aminoisobutyric acid, serum UDP-galactosyltransferase, and urinary hydroxyproline. Structurally related groups of biomarkers included six modified nucleosides and three polyamines analyzed in urine, and three serum protein-bound neutral carbohydrates. The respective chromatographic methods developed for these latter biochemical materials enabled all the individual compounds in each group to be quantitated simultaneously in one analytical run. The general frequency and degree of elevation for the total number of biomarkers was directly proportional to increasing tumor burden with specific exceptions, human chorionic gonadotropin and beta-aminoisobutyric acid. Galactosyltransferase was the most frequently elevated in the limited disease categories. Several of the biomarkers were elevated in the majority of patients with advanced disease and appeared potentially superior to carcinoembryonic antigen or human chorionic gonadotrophin.

The synthesis of a proteinase inhibitor, alpha-1-antichymotrypsin, by human breast epithelial cells

The synthesis and release of glycoproteins were studied in organ cultures of human breast surgical specimens and in established breast epithelial cell lines, MCF-7 and MDA-MB-231. Biosynthesis was monitored by the incorporation of 14C-glucosamine. Labeled macromolecules in the culture supernatants were analyzed by biochemical and immunological techniques. One to 8% of the labeled glycoproteins from benign breast and infiltrating ductal carcinoma specimens was precipitated by antibodies produced against human serum alpha-1-antichymotrypsin. Twelve percent of the total glycoproteins from the culture supernatants of the MCF-7 cell line was identified as alpha-1-antichymotrypsin. Both the normal serum and the human breast epithelia-derived proteinase inhibitor can be resolved into similar subclasses by two-dimensional gel electrophoresis. MDA-MD-231 and MCF-7 cells which were extensively washed with EDTA, serum-free medium, and phosphate-buffered saline retain this proteinase inhibitor on their cell surfaces. Three to 4% of the total cell-surface iodinated components was immunoprecipitated by these specific antibodies. Since alpha-1-antichymotrypsin is a potent inhibitor of neutral proteinases such as cathepsin G, the demonstration of its synthesis by benign and malignant breast epithelial cells is of considerable interest. This glycoprotein may represent the epithelia's own protective shield of cell surface components and the cell's attempt to moderate the effects of invading leukocytes. In addition, it may play a regulatory role in the maintenance of three-dimensional glandular structures.