engleski

Cytogenetic effects of vincristine on human lymphocytes in vitro

Vincristine belongs to vinca alkaloids, antineoplastic agents, and has been used in various chemotherapeutic regimens. The genotoxic potential of vincristine is assessed on human peripheral blood lymphocytes following administration of the drug at doses within the therapeutic range (0.05 ƒÝg/ml) by use of cytokinesis-blocked micronucleus assay combined with Giemsa and DAPI staining techniques. In vitro treatment of human lymphocytes with vincristine was performed on cells in G0 phase and lasted for 24 h. Afterwards, lymphocytes were cultured in vitro for 72 h. By use of Giemsa staining in vincristine-treated sample 1000 cells were analysed and 68 micronuclei, 77 multimicronucleated cells as well as 136 C-mitoses were recorded. In control sample, neither C-mitoses nor multimicronuclear cells were observed. On 1000 analysed cells only 5 micronuclei were recorded. By use of DAPI staining in vincristine-treated sample 1000 cells were analysed and 77 micronuclei, 81 multimicronucleated cells as well as 153 C-mitoses were recorded. In control sample, on 1000 analysed cells only 7 micronuclei were recorded. On the basis of DAPI flourescence signals, micronuclei were divided in signal-positive and signal-negative. In vincristine-treated sample 66.2% micronuclei were signal-positive and 33.8% signal-negative, while in control there were 42.9% signal-positive and 57.1% signal-negative micronuclei. Observed differences were tested by means of Łq2 test, and it was found out that they are statistically significant. Results obtained in this study by use of micronucleus assay combined with Giemsa and DAPI staining techniques confirmed that vincristine exhibit predominantly aneugenic effects on human lymphocytes.

vincristine; micronucleus; DAPI; genotoxicity

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