FIG. 8.

Mitotic index analysis demonstrates a G₂ arrest associated with T-cadherin-overexpression. (A) The V2 vector clone and the T3 T-cadherin-overexpressing clone cells were serum starved and then stimulated with DMEM containing 10% serum. Mitotic index analysis was performed as described in the Materials and Methods section at 0, 4, 8, 12, 24, and 48 h after serum stimulation. The means and SDs (error bars) were determined for each time point. T3 demonstrates a lower mitotic index at every time point compared with V2. The mitotic index data and the cell cycle analysis results are graphically represented in panel B.(B) For clone V2, the percentage of cells in G₂/M phase was comparable to the observed mitotic index at 12, 24 and 48 h after serum stimulation. In contrast, the percentage of T3 cells in G₂/M phase was significantly higher than the mitotic index at 12, 24, and 48 h after serum stimulation. The single asterisk denotes a statistically significant increase in percentage of G₂/M phase cells (P < 0.01). Error bars, SDs. (C) Propidium iodide staining demonstrates that T-cadherin-overexpressing cells have rounder and larger nuclei compared to vector-transfected C6 cells (arrowheads denote cells undergoing mitosis).