Vinorelbine: cell cycle kinetics and differential sensitivity of human lymphocyte subpopulations1The authors are members of the Research Career of CONICET (National Research Council).1 (original) (raw)

Comparison of the aneugenic effect of vinorelbine and vincristine in cultured human lymphocytes

Mutagenesis, 1999

Vinca alkaloids are used clinically against a variety of hematological and solid tumors. These compounds interact with tubulin subunits to prevent microtubule assembly, inducing abnormal chromosome segregation in dividing cells and causing aneuploidy. The vinca alkaloid vincristine sulfate (VCR) and the semisynthetic analog vinorelbine (VRB) were studied by analysis of micronuclei (MN) in cultured human lymphocytes using the cytokinesis block method. Futhermore, fluorescence in situ hybridization with a human alphoid satellite pancentromeric DNA probe was used to detect centromeres in isolated MN of VRB-or VCR-treated lymphocytes. At all the doses tested, both chemicals induced a significant increase in MN frequencies in binucleated (BN) cells (P < 0.001). The maximal effect was reached at a dose of 0.50 µg/ml. At this dose, VRB produced an~5-fold increase with respect to the control frequency of MN, while with VCR, this frequency increased 10-fold. Both drugs produced a slowing of the cell cycle, causing a decrease in the percentage of BN cells. This effect was lower with VRB. The percentages of centromerepositive MN were 89.79 and 87.60% in VRB-and VCRtreated cultures, respectively (control 27.03%). The high percentage of positive-signals in treated cultures (P < 0.001) indicates that the MN contained whole chromosomes. Our results confirm the aneugenic mode of action of these chemicals, VRB having less genetic effect.

Assessment of genotoxicity of vincristine, vinblastine and vinorelbine in human cultured lymphocytes: a comparative study

Balkan Journal of Medical Genetics, 2016

Vincristine (VCR), vinblastine (VBL) and vinorelbine (VRL) are anticancer agents from the Vinca alkaloid family that have the potential to induce genotoxic effect. The aim of the present study was to compare the genotoxic effect of VCR, VBL and VRL. Levels of 8-hydroxy-2-deoxy guanosine (8-OHdG) and sister chromatid exchanges (SCEs) were measured in cultured human blood lymphocytes treated with VCR, VBL and VRL at concentrations of 0.01 and 0.1 μg/mL. Results showed that VCR, VBL and VRL significantly increased the 8-OHdG levels (p <0.05), whereas it did not cause a significant increase in the frequencies of SCEs in human blood lymphocytes as compared to controls. On the other hand, all three agents significantly increased cells mitotic index (p <0.05). At both tested concentrations, the magnitude of the increase in 8-OHdG was VBL>VCR>VRL. In conclusion, VCR, VBL and VRL induce DNA damage as indicated by the increase in the 8-OHdG biomarker but with different magnitude.

In vitro inhibition of murine hematopoietic progenitors and stromal cells by vinorelbine

Cell biology and toxicology, 2000

Hematopoietic progenitor colony assays were used to establish the effects of the vinca alkaloid vinorelbine (VRB) on murine bone marrow. The in vitro growth of colony-forming units-granulocyte/macrophage (CFU-GM), burst forming units-erythroid (BFU-E) and colony-forming units-mix (CFU-mix) was dose-dependently inhibited by VRB. The highest dose assayed (0.02 microg/ml) suppressed all of the different progenitor cells by 100%. A comparison of the dose-response curves showed that CFU-GM, BFU-E, and CFU-mix exhibited similar-patterns of sensitivity to the cytotoxic action of VRB. Long-term bone marrow cultures have provided a valuable in vitro model for studying the role of the microenvironment of bone marrow. Cellularity of stromal layers was reduced with increasing doses of VRB. The appearance of these layers was altered minimally with the lowest dose used; a gradual loss of cellularity was seen in cultures exposed to 0.05 and 0.075 microg/ml; and a marked loss at the dose of 0.1 mic...

Comparative uptake, retention and action of vincristine, vinblastine and vindesine on murine leukaemic lymphoblasts sensitive and resistant to vincristine

British Journal of Pharmacology, 1988

The uptake and retention of vincristine (VCR), vinblastine (VBL) and vindesine (VDS) were evaluated comparatively with respect to their cytotoxic action on a murine lymphoblastic leukaemia (L5178Y). 2 The same parameters were measured on a derived subline of cells resistant to VCR (L5178Y/r) in order to determine whether the different degree of resistance to each alkaloid correlates with the amount of drug associated with the cells. 3 VCR was the most active on L5178Y cells (IC50 = 5.8 x 1O-9M) while the activity of VBL and that of VDS were similar (IC50 4.4 x 10-8 M and 3.5 x 10-8M, respectively). Nevertheless, a considerably larger amount of VBL was taken up by the cells compared to VDS, although there were no significant differences in their cytotoxic action. 4 The VCR resistant cell line also expressed resistance to VDS, whose ICo was increased by a factor of 11.4, but not to VBL. However, the uptake and retention of the three alkaloids were similarly reduced in L5178Y/r cells regardless of the degree of resistance expressed. 5 Although a decreased drug uptake and/or retention by the cells provides an explanation for the resistance to vinca alkaloids, they do not seem to be the only factors accounting for the resistance shown by the cell line which we have isolated. 6 The results seem to indicate that part of the VBL taken up by the cells is not used to induce the cytotoxic effect, but is diverted to some cellular compartment(s) or rate controlling process(es) which are different from the target that mediates its cytotoxic action.

Induction of micronuclei in cultured human lymphocytes treated with vinblastine before and after mitogen stimulation

Mutation Research Letters, 1994

The analysis of micronuclei (MN) in cultured human lymphocytes can, in principle, detect exposure to clastogens and aneuploidogens alike. As aneuploidogens such as spindle poisons usually act on dividing cells, it is not clear how an in vivo exposure of resting peripheral lymphocytes to an aneuploidogen could be transmitted and expressed as MN in cultured lymphocytes. This question is fundamental in judging if cultured lymphocytes can be used to detect in vivo exposure to aneuploidogens. In the present study, in vivo exposure of resting lymphocytes to an aneuploidogen was simulated in vitro by a 24-h pulse treatment of human lymphocytes with vinblastine sulfate (VBL) before mitogen stimulation, followed by two washes and culture in the presence of phytohemagglutinin (PHA) for 72 h. This treatment protocol did result in an increased MN frequency, but only at the highest concentration of VBL available for analysis (100 ng/ml). A more effective response, with a significant effect already at 40 ng/ml, was obtained when the 24-h pulse treatment was started at 24 h of PHA-stimulated 72-h cultures. Still much lower concentrations of VBL (1 or 2.5 ng/ml) were effective, when the treatment, started 24 h after culture initiation, was continued for 48 or 72 h (respectively) until cell harvest. These results demonstrate that MN induction by VBL depends, as expected, on the duration and timing of exposure, reflecting the availability of dividing cells during the treatment. The positive MN response obtained in the pulse-treated unstimulated lymphocytes may reflect an effect initiated in the resting stage and retained until mitosis or residual VBL left in the cells or in the cell suspension, despite the washes.

Effects of vincristine on cell survival, cell cycle progression, mitotic accumulation in asynchronously growing Sarcoma 180 cells

Cancer Research

The effects of vincristine (VCR) on cell survival, cell cycle progression, DMA synthesis, and metaphase accumulation were studied in relation to drug concentration and drug exposure duration in Sarcoma 180 cells in vitro. VCR was found to affect cells in interphase, producing a transient G2 block at all drug concentrations and drug exposure durations studied. VCR did not affect DMA synthesis directly. Increases in the metaphase index were delayed and always peaked at approximately 8 hr after drug removal, regardless of the duration of drug exposure. Increases in the metaphase index of sufficient magnitude to be commensurate with VCR lethality were observed only with pro longed drug exposure. VCR produced both nuclear fragmenta tion and polyploidy. The proportion of cells undergoing polyploidy increased progressively with increasing drug exposure duration. Interference with cytokinesis during prolonged VCR exposure may represent a lethal effect of VCR that is separate from its short-term effects. This could serve as the basis for the clinical study of the antitumor effects of prolonged VCR infusions. 0.5

Murine leukemia P388 vinorelbine-resistant cell lines are sensitive to vinflunine

Investigational New Drugs, 2008

The work presented here was initiated to explore the mechanisms underlying vinorelbine resistance in two previously established murine leukemia P388 cell lines (N.63 and N2.5). IC50 measurements demonstrated that the vinorelbine-resistant cell line N.63 was sensitive to both vinblastine and vinflunine. In addition, vinorelbine-resistant cell line N2.5 retained sensitivity to vinflunine. We used flow cytometry with propidium iodide to measure G2/M arrest in response to drug treatment. Annexin V labeling was used as a marker of apoptosis and JC-1 dye labeling as a marker of mitochondrial membrane depolarization to explore differential responses that might help explain the absence of cross resistance to vinflunine. At equipotent (10X IC50) doses, after 8 h of drug treatment, vinflunine induced G2/M arrest in a significantly larger fraction of vinorelbine- resistant cells compared to vinorelbine. At the same drug doses, at 16 h after initiation of drug treatment, vinflunine induced a statistically significant greater apoptotic response and mitochondrial depolarization. The mitochondrial depolarization at 16 h was confirmed by Western blotting that showed release of cytochrome c. Comparison of apoptotic and mitochondrial depolarization responses in vinorelbine-resistant cells upon exposure to vinorelbine, vinblastine and vinflunine demonstrated the following pattern of drug activity: vinflunine > vinblastine > vinorelbine, confirming the importance of a antimitotic-induced mitochondria-mediated pathways in these P388 cell lines. We conclude that vinflunine may be preferred for treatment of specific cancers compared to other vinca alkaloids due to its enhanced effects on apoptotic pathways that follow G2/M arrest.

The effects of low-dose vincristine on megakaryocyte colony-forming cells and megakaryocyte ploidy

British Journal of Haematology, 1984

The administration of low-dose vincristine (VCR) (0.1 mg/kg) to mice resulted in thrombocytosis without prior thrombocytopenia. No significant changes in marrow megakaryocyte numbers were found. However, after a minor early decrease, mean megakaryocyte ploidy increased, with a peak at 3 d. The number of megakaryocyte colony-forming cells (MEG-CFC) in bone marrow did not change significantly. In contrast with the effects on marrow, the concentration of megakaryocytes and the content of MEG-CFC in the spleen were significantly reduced for 1-2 d after VCR. This reduction was followed by a compensatory rise in the splenic content of MEG-CFC (peak 3-fold increase at 3 d). and 1-2 d later, an increase in splenic megakaryocytes which was concurrent with the increased platelet count. Culture of marrow and spleen cells in the presence of VCR resulted in inhibition of megakaryocyte colony formation at concentrations > 5 ng/ml and parallel reduction of the number of megakaryocytes per colony and the mean ploidy of colony megakaryocytes.

Effects of vincristine on cell survival, cell cycle progression, and mitotic accumulation in asynchronously growing sarcoma 180 cells

Cancer research, 1983

The effects of vincristine (VCR) on cell survival, cell cycle progression, DMA synthesis, and metaphase accumulation were studied in relation to drug concentration and drug exposure duration in Sarcoma 180 cells in vitro. VCR was found to affect cells in interphase, producing a transient G2 block at all drug concentrations and drug exposure durations studied. VCR did not affect DMA synthesis directly. Increases in the metaphase index were delayed and always peaked at approximately 8 hr after drug removal, regardless of the duration of drug exposure. Increases in the metaphase index of sufficient magnitude to be commensurate with VCR lethality were observed only with pro longed drug exposure. VCR produced both nuclear fragmenta tion and polyploidy. The proportion of cells undergoing polyploidy increased progressively with increasing drug exposure duration. Interference with cytokinesis during prolonged VCR exposure may represent a lethal effect of VCR that is separate from its short-term effects. This could serve as the basis for the clinical study of the antitumor effects of prolonged VCR infusions.

Effect of Vincristine on Bone Marrow Cells of Patients With Multiple Myeloma

Virchows Archiv B Cell …, 1980

The cytokinetic changes induced by Vincristine (VCR) on bone marrow erythroblasts, myeloid cells and neoplastic plasma cells have been studied in four patients with plasma cell malignancies using combined DNA cytofluorometry and in vitro tritiated thymidine cytoautoradiography. The changes observed 9 h after the administration of the drug were in accordance with its S-phase specificity. The magnitude of the stathmokinetic effect was in fact roughly proportional to the proliferative activity of the different cell lines, i.e., marked on the erythroblasts, less evident on the myeloid cells and still lower on the plasma cells. In this last cell population VCR has also blocked or partially impaired the DNA synthesis. Nine days after VCR, the plasma cells were recruited into the proliferative cycle while the regeneration of the hemopoietic cells was already exhausted. Repeated administrations of VCR spaced at about 9 day intervals are more and more effective on the plasma cell population, since the S phase specificity of the drug against the recruited plasma cells is potentiated. On the contrary, the regeneration of the hemopoietic cells is protected by this time interval.