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Background and objectives: Docetaxel is a chemotherapeutic agent commonly used for treatment of many cancers, including esophageal squamous cell carcinoma. Docetaxel induces G2/M phase cell cycle arrest and ultimately cell death. In this study, we aimed to assess the effects of docetaxel on YM1 cells considering exposure time and dose.
Methods: After calculating the doubling time of YM1 cells, the anti-proliferative effect of different concentrations of docetaxel () [A1]  after 24, 48 and 72 hours was assessed by the standard colorimetric assay. In addition, the effect of docetaxel on cell cycle was evaluated by flow cytometry.
Results: The results showed that docetaxel toxicity was not significant until 24 hours at the tested concentrations (P>0.05). In addition, the effect of docetaxel on the cells was time-dependent at all tested concentrations. Overall, the duration of exposure to docetaxel had more significant role in docetaxel toxicity in YM1 cells compared to concentration.
Conclusion: Our findings suggest that the cytotoxicity of docetaxel on YM1 cells is time-dependent.