guanosine/sarcoma

Adenosine phosphorylase (EC 2.4.2.-) activity present in Sarcoma 180 cells grown in culture and in rat liver, is shown to be distinct from inosine-guanosine phosphorylase by several criteria: (a) treatment of Sarcoma 180 cell extract with p-chloromercuribenzoate inhibited the two activities to a

The antitumor activity of 5-fluorouracil (FUra) against ascites Sarcoma 180 was significantly enhanced by coadministration of guanosine, and slightly by adenosine, but not by cytidine or uridine. In advanced ascites Sarcoma 180, guanosine also enhanced the action of FUra, but adenosine, uridine, and

The chemotherapeutic action of 5-fluorouracil monotherapy on HRS-Sarcoma in mice was compared with those of 5-fluorouracil nucleoside combinations (thymidine, cytidine or guanosine). The curative action of 5-fluorouracil was potentiated without increasing its toxicity, when cytidine or guanosine

A novel isozyme of lactate dehydrogenase is detected in various cells transformed by the Kirsten murine sarcoma virus (KiMSV). This isozyme, designated LDHk, is strongly inhibited by physiological concentrations of oxygen, in an apparently cooperative fashion. LDHk is inhibited by guanosine

The effects of the chiral isomers of erythro- and threo-9-(2-hydroxy-3-nonyl)adenines (EHNA and THNA) on purine metabolism in Sarcoma 180 cells have been determined. At concentrations of 10-80 microM [10- to 1000-fold greater than their Ki values with adenosine deaminase (ADA)], all isomers

DNA synthesis was studied in mouse ascites sarcoma cells using a permeable cell system. The sarcoma was induced by the Schmidt-Ruppin strain of Rous sarcoma virus. The cells were made permeable to nucleoside triphosphates by treatment with a hypotonic buffer containing 10 mM Tris Cl, 4 mM MgCl2, 1

Adenylate, guanylate cyclase and protein kinases in a fibrous sarcoma originating from rat prostate have been studied. A decrease in levels of adenosine 3', 5'-monophosphate (cyclic AMP) and adenylate cyclase activities and an increase in levels of guanosine 3',5'-monophosphate (cyclic GMP) and

The growth-inhibitory effect of 6-methylmercaptopurine riboside (MMPR) against leukemia L1210 cells in culture was dramatically potentiated by the addition of guanine nucleosides to the medium. In the presence of either deoxyguanosine or guanosine, the concentration of MMPR that caused 50%

The gene for the Harvey murine sarcoma virus (Ha-MuSV) p21ras protein was fused to the amino-terminal portion of the bacteriophage lambda cII gene on the expression vector pJL6. The fusion was such that transcription was controlled by the well-regulated phage lambda pL promoter, and translation

6-Methylmercaptopurine ribonucleoside (6-MMPR), an inhibitor of purine nucleotide biosynthesis de novo, was used as a model compound to evaluate the relationship between the levels of intracellular guanosine triphosphate (GTP) and the formation of cellular glycoproteins and their

Adenylate cyclase activity in particulate fractions from a transplantable rat osteogenic sarcoma was stimulated in a dose-dependent manner by prostaglandins E1 and E2 (PGE1 and PGE2) and parathyroid hormone (PTH). Prostaglandin F2alpha was active at a high concentration (3 x 10(-4) mol/l).

The chemotherapeutic effect of the 5-fluorouracil (5-FU)-guanosine 5'-monophosphate (GMP) combination in various mouse tumor systems was compared with that of 5-FU monotherapy. Antitumor activity of 5-FU against L-1210 leukemia was potentiated without increasing its toxicity to the host when GMP at

Regulation of adenylate cyclase coincident with transformation of chicken embryo fibroblasts by Rous sarcoma virus is manifest as a 10-50% decrease in basal, Mg2+-, and forskolin-stimulated activities; activities elicited by fluoride and guanosine 5'-O-(3-thiotriphosphate) are unaltered. The level