ABSTRACT
Six hundred triphenylethylenes were assayed for antiproliferative activity against MCF-7, LY2, and MDA-MB-231 breast cancer cells using sulforhodamine B dye to measure proliferation. Here we report on just 63 of the compounds, mostly clomiphene analogs, with substitutions on the alpha' or beta ring, at the vinyl position or in the side chain, of which 23 were active, as defined by antiproliferation IC50 values < or =1 microM. Activity profiles showed that 23 and 11 analogs were active toward MCF-7 and LY2, respectively, but none were active against MDA-MB-231. The IC50 values of tamoxifen were 2.0 microM against MCF-7 and 7.5 microM against LY2 and MDA-MB-231. Estradiol reversed antiproliferative activities of several E isomers but not their Z isomer counterparts. Clomiphene side chain analogs 46 [(E)-1-butanamine, 4-[4-(2-chloro-1,2-diphenylethenyl) phenoxy]-N,N-diethyl-dihydrogen citrate (MDL 103,323)] and 57 [(E)-N-[p-(2-chloro-1,2-diphenylvinyl) phenyl]-N,N-diethylethylenediamine dihydrogen citrate (MDL 101,986)] were 4- to 5-fold more effective than tamoxifen. Methylene additions up to (-CH2-)12 in the clomiphene side chain showed that analog 46 [(-CH2-)4 side chain] had maximal antiproliferative activity, binding affinity, and inhibition of transcription of an estrogen response element luciferase construct in transfected MCF-7 cells. Intraperitoneal administration of 46 or 57 inhibited progression of MCF-7 breast tumor xenografts in nude mice with ED50 values of <0.02 mg/mouse/day. Both analogs may hold promise for treating ER positive breast cancer and are of interest for further development.
Subject(s)
Antineoplastic Agents/pharmacology , Clomiphene/analogs & derivatives , Mammary Neoplasms, Experimental/drug therapy , Animals , Cell Division/drug effects , Clomiphene/pharmacology , Estradiol/pharmacology , Humans , Mice , Mice, Nude , Structure-Activity Relationship , Transplantation, Heterologous , Tumor Cells, CulturedABSTRACT
The synthesis and evaluation of farnesyl-derived inhibitors of ras farnesyl transferase are presented. Evaluation of inhibitors of farnesyl transferase and comparison with the previously described inhibitor was accomplished using purified enzyme and Amersham's Farnesyl:Transferase enzyme assay kit. These results show an order of magnitude increase in inhibitory activity for beta-ketophosphonic acid over beta-hydroxyphosphonic acid. Incorporation of fluorines in alpha-position, led to an increase in inhibitory activity over the nonfluorinated analogues.
Subject(s)
Alkyl and Aryl Transferases , Transferases/antagonists & inhibitors , Animals , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Humans , In Vitro Techniques , Oncogene Protein p21(ras)/metabolism , Organophosphonates/chemical synthesis , Organophosphonates/chemistry , Organophosphonates/pharmacology , Protein Prenylation , Structure-Activity Relationship , SwineABSTRACT
A simple and convenient microplate assay for glycosidases involved in the glycoprotein-processing reactions is described. The assay is based on specific binding of high-mannose-type oligosaccharide substrates to concanavalin A-Sepharose, while monosaccharides liberated by enzymatic hydrolysis do not bind to concanavalin A-Sepharose. By the use of radiolabeled substrates [( 3H]glucose for glucosidases and [3H]mannose for mannosidases), the radioactivity in the liberated monosaccharides can be determined as a measure of the enzymatic activity. This principle was employed earlier for developing assays for glycosidases previously reported (B. Saunier et al. (1982) J. Biol. Chem. 257, 14155-14161; T. Szumilo and A. D. Elbein (1985) Anal. Biochem. 151, 32-40). These authors have reported the separation of substrate from the product by concanavalin A-Sepharose column chromatography. This procedure is handicapped by the fact that it cannot be used for a large number of samples and is time consuming. We have simplified this procedure and adapted it to the use of a microplate (96-well plate). This would help in processing a large number of samples in a short time. In this report we show that the assay is comparable to the column assay previously reported. It is linear with time and enzyme concentration and shows expected kinetics with castanospermine, a known inhibitor of alpha-glucosidase I.
Subject(s)
Glycoside Hydrolases/analysis , Animals , Glucose/metabolism , Glycoproteins/metabolism , Microchemistry/methods , Sepharose , Swine , Tritium , alpha-Glucosidases/analysisSubject(s)
Antineoplastic Agents , Spermidine/analogs & derivatives , Adenosylmethionine Decarboxylase/metabolism , Animals , DNA, Neoplasm/biosynthesis , HeLa Cells , Leukemia L1210/drug therapy , Lymphoma/drug therapy , Male , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , Mitosis/drug effects , Neoplasm Proteins/biosynthesis , Ornithine Decarboxylase/metabolism , Spermidine/pharmacologyABSTRACT
Three groups of lysine-excreting, thialysine-resistant mutants of Saccharomyces cerevisiae were derived from the wild-type strain (X2180) by mutagenic treatment and selected on the basis of a cross-feeding assay. Mutants MNNG2-9, MNNG2-27, MNNG2-39 and MNNG2-62 (group 1) exhibited a 2:2 segregation for thialysine resistance following mating with a wild-type strain and a lower than wild-type lysyl-tRNA synthetase activity; the thialysine-resistant phenotype was dominant in specific hybrids. Mutant MNNG2-2 (group II) was similar to group I mutants except that the thialysine-resistant phenotype was recessive in the hybrid. Mutant MNNG3-142 (group III) exhibited an irregular ratio of segregation of thialysine resistance and a significantly lower lysyl-tRNA synthetase activity; the thialysine-resistant phenotype was recessive in the hybrid. The growth of both group I and group III mutants was temperature-sensitive. The thialysine-resistant mutants exhibited pleiotropic properties including the increased production and excretion of lysine, thermosensitive growth and an impairment of lysyl-tRNA synthetase activity.
