Detection of 1,2,4-benzenetriol induced aneuploidy and microtubule disruption by fluorescence in situ hybridization and immunocytochemistry

Fluorescence in situ hybridization (FISH) is becoming increasingly used to detect chromosomal changes in cancer cytogenetics. Here, we report its use in human HL60 cells to detect aneuploidy induced by the benzene metabolite, 1,2,4-benzenetriol (BT). Human centromeric probes specific for chromosomes 9 and 7 were used. Untreated HL60 cells were 0.72 +/- 0.29% hyperdiploid for chromosome 9. Treatment with 5 microM BT increased this level 3-fold to 2.20 +/- 0.87% and 50 microM increased it 4-fold to 2.96 +/- 0.74%. Similar results were obtained with the chromosome 7 probe. The induction of aneuploidy by BT is therefore not chromosome-specific nor is it artifactual. Immunocytochemical staining with anti-tubulin antibodies also showed that BT disrupted microtubule organization at these concentrations. Thus, mitotic spindle disruption probably plays an important role in BT-induced aneuploidy. Trisomy and not tetrasomy accounted for the majority of the hyperdiploidy induced by BT in the two C-group chromosomes 7 and 9. Since trisomy of C-group chromosomes is commonly observed in leukemia, BT-induced aneuploidy may be involved in benzene-induced leukemia.