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Synthesis of a Fluorescent Analogue of Paclitaxel That Selectively Binds Microtubules and Sensitively Detects Efflux by P-Glycoprotein.

ABSTRACT: The anticancer drug paclitaxel (Taxol) exhibits paradoxical and poorly understood effects against slow-growing tumors. To investigate its biological activity, fluorophores such as Oregon Green have been linked to this drug. However, this modification increases its polarity by approximately 1000-fold and reduces the toxicity of Taxol towards cancer cell lines by over 200-fold. To construct more drug-like fluorescent probes suitable for imaging by confocal microscopy and analysis by flow cytometry, we synthesized derivatives of Taxol linked to the drug-like fluorophore Pacific Blue (PB). We found that PB-Gly-Taxol bound the target protein β-tubulin with both high affinity in vitro and high specificity in living cells, exhibited substantial cytotoxicity towards HeLa cells, and was a highly sensitive substrate of the multidrug resistance transporter P-glycoprotein (P-gp).

SUBMITTER: Lee MM

PROVIDER: S-EPMC5679005 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Synthesis of a Fluorescent Analogue of Paclitaxel That Selectively Binds Microtubules and Sensitively Detects Efflux by P-Glycoprotein.

Lee Molly M MM Gao Zhe Z Peterson Blake R BR

Angewandte Chemie (International ed. in English) 20170509 24

The anticancer drug paclitaxel (Taxol) exhibits paradoxical and poorly understood effects against slow-growing tumors. To investigate its biological activity, fluorophores such as Oregon Green have been linked to this drug. However, this modification increases its polarity by approximately 1000-fold and reduces the toxicity of Taxol towards cancer cell lines by over 200-fold. To construct more drug-like fluorescent probes suitable for imaging by confocal microscopy and analysis by flow cytometry ...[more]

PMID: 28485901

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