Human interferon ß(IFN-/Î) stimulated the synthesis of prostaglandin E (PGE) and prostaglandin F2o in IFN-sensitive RSa and GM258 cell lines, but not in IFN-resistant HEC-1 cells. IFN-/S at a concentration of 1000 units/ml elicited 2to 3-fold increases in PGE production in these cell lines. In the presence of exogenous arachidonic acid (1 jug/ml), IFN-pretreated cells produced 5-fold more PGE...

The metabolism of aflatoxin B, has been investigated in male rhesus monkeys given i.p. injections of a mixture of ring-labeled aflatoxin B!-'4C and nonradioactive toxin, at a total dose of 0.4 mg/kg. Thirty-five % of the administered radioactivity was excreted in urine within 96 hr. The excretion rate reached a maximum 1 hr after dosing and then fell rapidly, but urine excreted after 96 hr stil...

p53 induction and cell cycle arrest occur following DNA damage, possibly to allow repair prior to replication. p21WAFI/CIP11a cyclin-cyclindependent kinase inhibitor and proliferating cell nuclear antigen-inter acting protein, is induced by p53 and mediates the cell cycle arrest. To investigate a role for p21 in DNA repair in vivo, we studied the expression of in vitro damaged reporter DNA tran...

The possible roles in experimental colon carcinogenesis of two protooncogenes (c-myc and c-H-ras), two endogenous retrovirus-related DNA sequences (rat leukemia virus (RaLV) and the 30S sequence), and two cell cycle related genes (ß-actinand ornithine decarboxylase) were studied by analyzing the levels of their corresponding RNAs during the course of azoxymethane induced and high fat promoted ...

To examine whether the fidelity of DNA synthesis is reduced in tumor cells, M13 mp2-based fidelity assays were carried out using 15 samples of whole-cell extracts from primary mouse thymic lymphomas induced by alkylating agents. We found that DNA synthesis activities of thymic lymphomas, detected as incorporation of [3H]TTP into acid-insoluble materials, were 2to 10-fold higher compared to thos...

Transplantable renal adenocarcinoma can be readily induced in Wistar strain male rats by initiation with A/-ethyl-W-hydroxyethylnitrosamine followed by promotion with ß-cyclodextrin. The transplantability rates of the tumors by s.c. inoculation in new born rats were 33 and 50%, respectively, for tumors of the first and second passages, and 100% for both third and fourth passages. The transplan...

Galectin-3 (Gal-3) ¡sa ß-galactoside-binding protein with Mr ~30,000. Cell surface Gal-3 is postulated to be involved in homotypic aggregation of tumor cells in the circulation during metastasis through attachment to a complementary serum glycoprotein(s), which serves as a cross-linking bridge between adjacent cells. To test this hypothesis a recombinant strain of baculovirus encoding Gal-3 w...

Pseudoisocytidine (*ICyd) is a C-nucleoside with enhanced stability and resistance to enzymatic deamination when com pared to 5-azacytidine and 1-ß-D-arabinofuranosylcytosine. Elimination kinetics in plasma using [14C]^ICyd showed a ßphase fi/2 for 14C of 2 hr and a yS-phase f,/2 of unchanged ¥ICyd of 1.5 hr. Net recovery of radioactivity in urine over 24 hr varied between 40 and 80% of the ...

The in vivo invasion of cartilage of the xiphisternum by a transplantable malignant rat tumor has been investigated with histochemical methods. Staining of cartilage with toluidine blue was considerably reduced or absent at the edge of the invading tumor. Frequently, matrix staining around chondrocytes close to the tumor was much more intense than that of more remote matrix. This pericellular s...

The relationship between calcium ions and the differentiation of human promyelocytic leukemia HL-60 cells was investigated. Proliferation of HL-60 cells incubated in calcium-free medium was inhibited without cell differentiation. On the other hand, incubation with 100 /¿Mverapamil markedly inhibited cell proliferation and caused slight cell differentiation into monocytes. Both calcium-free med...