HTI-286, a synthetic analogue of hemiasterlin, depolymerizes microtubules and is proposed to bind at the Vinca peptide site in tubulin. It has excellent in vivo antitumor activity in human xenograft models, including tumors that express P-glycoprotein, and is in phase II clinical evaluation. To identify potential mechanisms of resistance induced by HTI-286, KB-3-1 epidermoid carcinoma cells wer...

BACKGROUND Anti-mitotic compounds (microtubule de-stabilizers) such as vincristine and vinblastine have been shown clinically successful in treating various cancers. However, development of drug-resistance cells limits their efficacies in clinical situations. Therefore, experiments were performed to determine possible drug resistance mechanisms related to the application of anti-mitotic cancer ...

background: there are only four drugs for treating african trypanosomiasis, a devastating disease in sub-saharan africa. with slow discovery of better drugs, vaccination is viewed as the best method of control. we previously showed that antibodies to native trypanosoma brucei brucei tubulin inhibit the growth of trypanosomes in culture. here, we aimed to determine the effect of antibodies to ba...

Previous work from our laboratory suggested that microtubules are released from the neuronal centrosome and then transported into the axon (Ahmad, F.J., and P.W. Baas. 1995. J. Cell Sci. 108: 2761-2769). In these studies, cultured sympathetic neurons were treated with nocodazole to depolymerize most of their microtubule polymer, rinsed free of the drug for a few minutes to permit a burst of mic...

The epothilones (Epos) are a group of natural products isolated from the myxobacterium, Sorangium cellulosum. They have a mechanism of action similar to that of Taxol, i.e., they stabilize microtubules and induce the formation of microtubule bundles in cells. Because they are simpler in structure than Taxol and preserve their activity in P-glycoprotein-expressing cells, they are being studied a...

The epothilones (Epos) are a group of natural products isolated from the myxobacterium, Sorangium cellulosum. They have a mechanism of action similar to that of Taxol, i.e., they stabilize microtubules and induce the formation of microtubule bundles in cells. Because they are simpler in structure than Taxol and preserve their activity in P-glycoprotein-expressing cells, they are being studied a...

Normal interphase PtK2 and A549 cells display long microtubules radiating from the microtubule-organizing center (MTOC) to the plasma membrane. Both MTOC and Golgi apparatus are contained in the same perinuclear area. Treatment of cells with 1 microM colcemid for 2 h results in microtubule depolymerization and fragmentation of the Golgi apparatus into elements scattered throughout the cytoplasm...

The subunit protein of microtubules, tubulin, has been demonstrated to be present in isolated nerve endings by gel electrophoresis, amino acid composition, and peptide mapping. The tubulin constitutes approximately 28% of the soluble protein of the nerve endings . The transport of tubulin to the nerve endings has been demonstrated and its relationship to slow transport is discussed . ponent of ...

TPPP/p25 (tubulin polymerization-promoting protein/p25) is an unstructured protein that induces microtubule polymerization in vitro and is aligned along the microtubule network in transfected mammalian cells. In normal human brain, TPPP/p25 is expressed predominantly in oligodendrocytes, where its expression is proved to be crucial for their differentiation process. Here we demonstrated that th...