Table 2.
Enrichment of cancer stem cell subpopulation in CSPG4+ cells in pleural effusions from patients with breast cancer*
| Patient sample | CD44hi/CD24lo/− population in CD45−Lin− cells (%) | Percent of CD44hi/CD24lo/− cells in CSPG4− cells (fold enrichment) |
|||||
| CSPG4-specific mAb 225.28 | CSPG4-specific mAb 763.74 | CSPG4-specific mAb TP41.2 | CSPG4-specific mAb TP61.5 | Average value of the four CSPG4-specific mAbs† | Highest value of the four CSPG4-specific mAbs | ||
| PC-P4 | 2.91 | 8.6 (2.96) | 5.7 (1.96) | 10.2 (3.51) | 24.7 (8.49) | 12.3 (4.23) | 24.7 (8.49) |
| PC-P5 | 16.3 | 26.8 (1.64) | 68.9 (4.23) | 23.7 (1.45) | 18.3 (1.12) | 34.4 (2.11) | 68.9 (4.23) |
| PC-P6 | 7.21 | 4.7 (0.65) | 0.0 (0.00) | 3.57 (0.50) | 50.0 (6.93) | 14.6 (2.02) | 50.0 (6.93) |
| PC-P7 | 19.2 | 35.5 (1.85) | 95.4 (4.97) | 61.3 (3.19) | 75.4 (3.93) | 66.9 (3.48) | 95.4 (4.97) |
| PC-P8 | 18.0 | 2.9 (0.16) | 60.7 (3.37) | 20.9 (1.16) | 31.3 (1.74) | 29.0 (1.61) | 60.7 (3.37) |
| PC-P9 | 3.38 | 22.6 (6.69) | 40.2 (11.90) | 38.5 (11.40) | 35.7 (10.60) | 34.3 (10.10) | 40.2 (11.90) |
| PC-P10 | 31.6 | 91.5 (2.90) | 96.8 (3.06) | 93.7 (2.97) | 94.8 (3.00) | 94.2 (2.98) | 96.8 (3.06) |
| PC-P11 | 13.0 | 67.4 (5.18) | 93.3 (7.18) | 70.3 (5.41) | 75.5 (5.81) | 76.6 (5.89) | 93.3 (7.18) |
| PC-P12 | 4.94 | 13.5 (2.73) | 96.2 (19.50) | 90.3 (18.3) | 67.3 (13.60) | 66.8 (13.5) | 96.2 (19.50) |
| PC-P13 | 11.6 | 71.0 (6.12) | 81.4 (7.02) | 68.7 (5.92) | 76.7 (6.61) | 74.5 (6.42) | 81.4 (7.02) |
| PC-P14 | 12.2 | 8.4 (0.69) | 91.5 (7.50) | 49.1 (4.02) | 32.0 (2.62) | 45.3 (3.71) | 91.5 (7.50) |
| PC-P15 | 58.7 | 69.3 (1.18) | 90.3 (1.54) | ND | ND | 79.8 (1.36) | 90.3 (1.54) |
| Average‡ | 16.59 | 35.2 (2.73) | 68.4 (6.02) | 48.2 (5.25) | 52.9 (5.86) | 52.4 (4.78) | 74.1 (7.14) |
Tumor cells were isolated from the pleural effusions of 12 patients with metastatic breast cancer and incubated sequentially with the chondroitin sulfate proteoglycan 4 (CSPG4)–specific monoclonal antibodies (mAbs) (225.28, 763.74, TP41.2, or TP61.5), phycoerythrin-labeled anti-mouse IgG antibodies, and fluorescein isothiocyanate–labeled anti-CD24, allophycocyanin-labeled anti-CD44, peridinin chlorophyll protein–labeled anti-CD45 antibodies, and 7-aminoactinomycin D (7-AAD). Stained cells were subjected to flow cytometry analysis. The percentages of CD44hi/CD24lo/− cells in the CD45−/7-AAD− population and in the CD45−/7-AAD−/CSPG4+ population were determined. Enrichment of CD44hi/CD24lo/− population by gating at CSPG4+ cells was calculated by dividing the percentage of CD44hi/CD24lo/− cells in the CD45−/7-AAD−/CSPG4+ population by that in the CD45−/7-AAD− population; fold enrichment is shown in parenthesis. ND = Not done.
The average % (fold enrichment) of CD44hi/CD24lo/− in CSPG4+ cells, detected by four different CSPG4-specific mAbs, in each patient sample.
The average % (fold enrichment) of CD44hi/CD24lo/− in CSPG4+ cells, detected by four different CSPG4-specific mAbs, in all 12 patient samples.