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A-204197, a new tubulin-binding agent with antimitotic activity in tumor cell lines resistant to known microtubule inhibitors.
- Source :
-
Cancer research [Cancer Res] 2001 Jul 15; Vol. 61 (14), pp. 5480-5. - Publication Year :
- 2001
-
Abstract
- Drug resistance is a prevalent problem in the treatment of neoplastic disease, and the effectiveness of many clinically useful drugs is limited by the fact that they are substrates for the efflux pump, P-glycoprotein. Because there is a need for new compounds that are effective in treating drug-resistant tumors, we tested A-204197 (4-[4-acetyl-4,5-dihydro-5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazol-2-yl]-N,N-dimethylbenzeneamine), a novel oxadiazoline derivative with antiproliferative properties, on cell lines that were either sensitive or resistant to known microtubule inhibitors. Cell lines that were resistant to paclitaxel, vinblastine, or colchicine were equally sensitive to A-204197 (proliferation IC50s ranging from 36 to 48 nM) despite their expression levels of P-glycoprotein. The effect of A-204197 on cell growth was associated with cell cycle arrest in G2-M, increased phosphorylation of select G2-M checkpoint proteins, and apoptosis. In competition-binding assays, A-204197 competed with [3H]-labeled colchicine for binding to tubulin (K(i) = 0.75 microM); however, it did not compete with [3H]-labeled paclitaxel. A-204197 prevented tubulin polymerization in a dose-dependent manner (IC50 = 4.5 microM) in vitro and depolymerized microtubules in a time-dependent manner in cultured cells. These findings indicate A-204197 is a promising new tubulin-binding compound with antimitotic activity that has potential for treating neoplastic diseases with greater efficacy than currently used antimitotic agents.
- Subjects :
- Antineoplastic Agents metabolism
Apoptosis drug effects
Binding Sites
Cell Cycle drug effects
Cell Cycle Proteins drug effects
Cell Cycle Proteins metabolism
Cell Division drug effects
Colchicine metabolism
Colchicine pharmacology
Drug Interactions
Drug Resistance, Multiple
G2 Phase drug effects
Humans
Microtubules metabolism
Mitosis drug effects
Oxadiazoles metabolism
Paclitaxel pharmacology
Phosphorylation drug effects
Proto-Oncogene Proteins c-bcl-2 drug effects
Proto-Oncogene Proteins c-bcl-2 metabolism
Time Factors
Tubulin metabolism
Tumor Cells, Cultured drug effects
Tumor Cells, Cultured metabolism
Vinblastine pharmacology
Antineoplastic Agents pharmacology
Microtubules drug effects
Oxadiazoles pharmacology
Subjects
Details
- Language :
- English
- ISSN :
- 0008-5472
- Volume :
- 61
- Issue :
- 14
- Database :
- MEDLINE
- Journal :
- Cancer research
- Publication Type :
- Academic Journal
- Accession number :
- 11454695