Table 1

Cell cycle analysis and apoptosis by rituximab, paclitaxel, and combination treatment of Ramos and 2F7 NHL cell lines

TreatmentG0-G1SG2-MApoptosis
Ramos
Control42.0 ± 6.225.7 ± 2.927.1 ± 3.83.8 ± 0.7
DMSO38.3 ± 3.728.1 ± 4.126.1 ± 6.56.0 ± 2.2
Rituximab (20 μg/ml)37.5 ± 5.128.0 ± 4.130.3 ± 5.22.7 ± 0.6
Paclitaxel (1 nm)16.8 ± 0.49.2 ± 1.360 ± 1.513.3 ± 1.8
Paclitaxel (10 nm)26.4 ± 2.820.1 ± 8.539.9 ± 612.4 ± 0.8
Rituximab (20 μg/ml) + paclitaxel (1 nm)24.3 ± 4.119.3 ± 0.922.5 ± 0.735.5 ± 5.1a
Rituximab (20 μg/ml) + paclitaxel (10 nm)19.6 ± 3.216.3 ± 3.921.4 ± 2.945.3 ± 2.5a
2F7
Control48.8 ± 6.320.4 ± 1.123.5 ± 6.06.5 ± 1.7
DMSO49.4 ± 1.420.1 ± 0.522.5 ± 27.2 ± 1.5
Rituximab (20 μg/ml)54.6 ± 1.618.6 ± 0.618.1 ± 1.87.9 ± 0.6
Paclitaxel (1 nm)22.1 ± 2.29.8 ± 2.246 ± 1.921.2 ± 2.4
Paclitaxel (10 nm)18.1 ± 1.614.4 ± 3.248.1 ± 3.818.7 ± 1.9
Rituximab (20 μg/ml) + paclitaxel (1 nm)23.7 ± 3.67.5 ± 2.246.2 ± 3.822.3 ± 2.4b
Rituximab (20 μg/ml) + paclitaxel (10 nm)29.8 ± 7.315.2 ± 4.942.9 ± 110.8 ± 1.3b
  • Note: The cells (Ramos and 2F7) were either left untreated (control) or pretreated with rituximab (20 μg/ml, 48 h). Thereafter, the cells were washed, fresh medium was added, and the cells were incubated with various concentrations of paclitaxel (1 and 10 nm, 16 h). At the end of the incubation period, the cells were stained with PI solution and cell cycle analysis was assessed by flow cytometry. The percent apoptosis was determined as the percentage of hypodiploid cells accumulated at the sub-G0 phase of the cell cycle. The results are represented as mean ± SD (n = 3).

  • a P < 0.001 (very significant).

  • b Not significant compared with paclitaxel treatment alone.