Fig. 3

Analysis of apoptosis and percent distribution of KLE cells in the cell cycle as determined by flow cytometry. (Upper panel) Insulin-like growth factor-1 (IGF-1; 50 ng/ml) increased the percent distribution of KLE cells at the S phase from 35% ± 1.5 of controls to 43.5% ± 2 of IGF-1-treated KLE cells, mainly at the expenses of percent distribution of KLE cells at G1/G0 phase (from 55.5% ± 3 of controls to 47% ± 1.5 of IGF-1-treated KLE cells). These data corroborated the mitogenic action of IGF-1 on KLE cells, described in the Fig. 1. Practically, there existed no apoptotic cells in control and IGF-1-treated KLE cells. (Lower panel) Adriamycin (100 nM) induced the apoptosis of KLE cells, as noted by the increased percent distribution of KLE cells at <G1 phase in the cell cycle, from 1.5% ± 1 of controls to 29.5 ± 1.5% of adriamycin-treated KLE cells. In addition, adriamycin remarkably increased the percent distribution of KLE cells in the G2/M phase at the expenses of G1/G2 and S phases (G2/M phase increased from 9.5% ± 2.2 of controls to 74.5% ± 3.0 of adriamycin-treated KLE cells; whereas, G1/G0 phase decreased from 55.5% ± 3.0 of controls to 10% ± 2.0 in adriamycin-treated KLE cells and S phase decreased from 35% ± 1.5 in controls to 15.5% ± 2.2 of adriamycin-treated KLE cells (p < 0.001). Therefore, adriamycin arrested KLE cells at G2/M phase and induced apoptosis of KLE cells. IGF-1 (50 ng/ml) decreased percent distribution at G2/M phase by 50% and percent distribution at <G1 phase by 38% of adriamycintreated KLE cells (p < 0.001).