Calorie restriction reduces mammary mitogenesis and tumorigenesis. To test whether epidermal growth factor (EOF) levels are influenced by calorie intake, 72 four-week-old C3H/HeOu mice were separated into two groups and either fed ad libitum (group AL) or calorie-restricted at a mean 19% (group CR). Three mice from each group were evaluated when 6, 8,10, and 12 weeks old for submandibular gland...

Previously, we have shown that galaptin, an endogenous ß-galactosidebinding lectin, is present in extracellular matrix where it may participate in the adhesion of AI21 human ovarian carcinoma cells to extracellular matrix via interaction with specific cell surface carbohydrate receptors. We now report that A121 cells adhere to polystyrene plates coated with polymerized human splenic galaptin. ...

Chemical and histochemical studies of three lysosomal enzymes-acid phosphatase, ß-glucuronidase, and cathepsinshowed that these enzymes increase during the regression of estrone-induced mammary tumors. One week after removal of the estrone pellet, the tumors had regressed by 50%, at which time acid phosphatase had increased by 67%, cathepsin by 111%, and 0-glucuronidase by 138%. At Week 2, alt...

Pyrimidine nucleoside monophosphate kinase (EC 2.7.4.14) catalyzes the phosphorylation of various pyrimidine nucleoside monophosphates to their corresponding diphosphates. In addition to its role in the synthesis of nucleic acid precursors, this enzyme is essential for the conversion of the antileukemic agent 1-/3-o-arabinofuranosylcytosine to its active metabolite 1-/3-o-arabinofuranosyl 5 -tr...

The S-nitrobenzyl derivatives of 6-thio-9-/3-D-ribofuranosylpurine and 2-amino-6-thio-9-ß-D-ribofuranosylpurine (i.e.), and 6-[(4-nitrobenzyl)thio] -9-ß-D-ribofuranosylpurine (NBMPR) and 2-amino-6-[(4-nitrobenzyl)thiol] -9-0-D-ribofuranosylpurine, respectively), which have been previously recognized as potent inhibitors of nucleoside transport, protected cultured L5178Y cells against the anti...

Mutations in long lived stem cells are critical events in carcinogenesis. The Dlb-1 assay detects intestinal stem cell mutation at the Dlb-I locus in Dlb-1"'' heterozygous mice by visualizing mutated clones of epithelial cells in \iiii which do not bind the lectin Dolichos bifloras agglutinin. We have used this assay to show that the food-derived heterocyclic amine 2-aminol-methyl-6-phenylimida...

Parathyroid hormone-related peptide (PTHrP) was originally isolated from tumors associated with the development of hypercalcémie in vivo. Analyses of PTHrP gene expression have demonstrated that PTHrP is also produced in a wide variety of normal fetal and adult nonneoplastic tissues. The results of recent experiments have demonstrated that PTHrP is a growth factor-regulated gene, and different...

Human tumors and tumor cell lines were analyzed for the presence of mRNA coding for transforming growth factors a and ß(TGF-a and -ft) and the epidermal growth factor receptor. TGF-a mRNA was not detect able in hematopoietic tumor cell lines but was found in a variety of solid tumor cells, particularly carcinomas. Many of the tumors that contained TGF-a mRNA also expressed high levels of epide...

In vitro modification of M13 phage single-stranded DMA with 4-hydroxyaminoquinoline 1-oxide (4HAQO) resulted in four kinds of adducts: three guanine adducts, QGh QGn, and QGm;and one adenine adduci, QA, at ratios of 16.4 47.3, 13.7, and 22.6, respectively. The carcinogen-modified DMA, initiated with a se quence-defined oligodeoxynucleotide primer, was replicated in vitro with Escherichia coli D...