title: Antizyme induction by polyamine analogues as a factor of cell growth inhibition.
abstract: The polyamines spermidine and spermine and their diamine precursor putrescine are essential for mammalian cell growth and viability, and strategies are sought for reducing polyamine levels in order to inhibit cancer growth. Several structural analogues of the polyamines have been found to decrease natural polyamine levels and inhibit cell growth, probably by stimulating normal feedback mechanisms. In the present study, a large selection of spermine analogues has been tested for their effectiveness in inducing the production of antizyme, a key protein in feedback inhibition of putrescine synthesis and cellular polyamine uptake. Bisethylnorspermine, bisethylhomospermine, 1,19-bis-(ethylamino)-5,10,15-triazanonadecane, longer oligoamine constructs and many conformationally constrained analogues of these compounds were found to stimulate antizyme synthesis to different levels in rat liver HTC cells, with some producing far more antizyme than the natural polyamine spermine. Uptake of the tested compounds was found to be dependent on, and limited by, the polyamine transport system, for which all these have approximately equal affinity. These analogues differed in their ability to inhibit HTC cell growth during 3 days of exposure, and this ability correlated with their antizyme-inducing potential. This is the first direct evidence that antizyme is induced by several polyamine analogues. Selection of analogues with this potential may be an effective strategy for maximizing polyamine deprivation and growth inhibition.
authors.affiliation: Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA. jmitchell@niu.edu
authors.forename: John L A
authors.initials: JL
authors.lastname: Mitchell
authors.forename: Aviva
authors.initials: A
authors.lastname: Leyser
authors.forename: Michelle S
authors.initials: MS
authors.lastname: Holtorff
authors.forename: Jill S
authors.initials: JS
authors.lastname: Bates
authors.forename: Benjamin
authors.initials: B
authors.lastname: Frydman
authors.forename: Aldonia L
authors.initials: AL
authors.lastname: Valasinas
authors.forename: Venodhar K
authors.initials: VK
authors.lastname: Reddy
authors.forename: Laurence J
authors.initials: LJ
authors.lastname: Marton
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004790:Enzyme Induction / Q000187:drug effects; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D008114:Liver Neoplasms, Experimental; D065108:Ornithine Decarboxylase Inhibitors; D011073:Polyamines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D014176:Protein Biosynthesis; D011506:Proteins; D051381:Rats; D013096:Spermine / Q000494:pharmacology; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured
chemical_list: D065108:Ornithine Decarboxylase Inhibitors; D011073:Polyamines; D011506:Proteins; C031017:ornithine decarboxylase antizyme; D013096:Spermine