Figure 5.

Increased frequency of multipolar (tripolar/tetrapolar) mitosis after hybridization. A: Tripolar (left panel) and tetrapolar (right panel) metaphases in MSC-MA11 hybrid cells revealed by DAPI staining of DNA (blue). B: Immunofluorescence for α-tubulin (red), revealing the multipolar configuration of the mitotic spindle in an MSC-MA11-EGFP breast carcinoma hybrid cell. Condensed chromosomes stained with DAPI (blue). C: Graph depicting the percentage of multipolar mitosis in the hybrids of breast carcinoma cells with MSC and the parental tumor cells, showing twofold to threefold greater multipolar mitosis in the heterotypic hybrids. Data represent the mean ± SD from three experiments, each one consisting of 100 metaphases plus anaphases analyzed per cell type. In parental MSCs, no multipolar mitosis was detected. Scale bar = 20 μm.