Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.1.1.17 (ornithine decarboxylase)
 6,351 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

When an 18-kDa cell surface sialoglycopeptide (SGP), isolated from intact bovine cerebral cortex cells, was incubated with exponentially growing Swiss 3T3 cells, cell proliferation was efficiently arrested. The inhibition was totally reversible since after removal of the SGP the arrested cells resumed their progress in the cell cycle in a synchronized manner for at least two divisions. Readdition of the GSP 4 h after reversal of the inhibition did not, however, affect the commitment of the cells to advance through metaphase, although progress through the cell cycle was once again inhibited after the cells reentered the G1 phase. The efficient nature of the SGP-mediated cell cycle arrest in G1 provided us with a basis to examine potential changes in the expression of several competence genes, and genes associated with mid and late G1, that have been implicated in cell cycle progression. Upon serum stimulation of quiescent Swiss 3T3 cells, the induction of c-myc and c-fos expression was not influenced by the SGP at concentrations highly inhibitory to cell cycling. Expression of JE was induced by serum, and the presence of the SGP had little effect on the expression of this growth-related gene. KC expression was not appreciably stimulated by serum although, surprisingly, the addition of the SGP resulted in a significant increase in expression. In addition, we learned that the SGP did not alter expression of ornithine decarboxylase, c-ras, or thymidine kinase, which are induced later than the genes associated with the initial stages of competence.
 ...
PMID:Modulation of growth-related gene expression and cell cycle synchronization by a sialoglycopeptide inhibitor. 190 95

The anti-tumor promoting activity of a polyphenolic fraction from grape seeds (GSP) was examined in CD-1 mouse skin epidermis. Specifically, the ability of this fraction to inhibit 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced tumor promotion and two markers of promotion in mouse skin, ornithine decarboxylase (ODC) and myeloperoxidase (MPO) activities, was evaluated. Pretreatment of mouse skin with 5, 10, 20 and 30 mg of GSP resulted in a dose-dependent reduction in TPA-induced epidermal ODC activity of 27, 37, 48 and 70%, respectively, compared to controls. In addition, pretreatment of mouse skin with 1, 5, 10 and 20 mg of GSP resulted in a significant 43, 39, 54 and 73% inhibition of MPO activity, respectively, compared to controls. In 7,12-dimethylbenz[a]anthracene (DMBA)-initiated CD-1 mice, biweekly treatment of mouse skin with 5, 10, and 20 mg of GSP 20 min prior to TPA application resulted in a 30, 40, and 60% inhibition of final skin tumor incidence, respectively, compared to controls. In addition, the final number of tumors per mouse in the 5, 10 and 20 mg GSP-treated animals was decreased 63, 51, and 94%, respectively, compared to controls. These studies indicate that GSP possesses anti-tumor promoting activity when applied to CD-1 mouse skin prior to treatment with TPA. The mechanism of this tumor inhibition is due, in part, to a GSP-associated inhibition of TPA-induced epidermal ODC and MPO activities. Thus, GSP warrants further evaluation as a skin cancer chemopreventative agent.
 ...
PMID:Inhibition of TPA-induced tumor promotion in CD-1 mouse epidermis by a polyphenolic fraction from grape seeds. 1009 23