Synergy between APO2/TRAIL and ATO in the induction of apoptosis in freshly isolated myeloma cells
| MM patients (% myeloma cells in BM before sorting) . | % apoptotic cells . | |||||
|---|---|---|---|---|---|---|
| TRAIL, day 1 . | ATO, day 1 . | TRAIL plus ATO, day 1 . | TRAIL, day 2 . | ATO, day 2 . | TRAIL plus ATO, day 2 . | |
| M1 (69) | 30 | 34 | 71 | 37 | 39 | 94 |
| M2 (41) | 17 | 33 | 69 | 38 | 47 | 95 |
| M3 (55) | 18 | 20 | 55 | 29 | 42 | 87 |
| M4 (36) | 30 | 26 | 70 | 42 | 45 | 92 |
| M5 (63) | 29 | 43 | 68 | 38 | 66 | 97 |
| M6 (77) | 20 | 46 | 77 | 44 | 64 | 99 |
| MM patients (% myeloma cells in BM before sorting) . | % apoptotic cells . | |||||
|---|---|---|---|---|---|---|
| TRAIL, day 1 . | ATO, day 1 . | TRAIL plus ATO, day 1 . | TRAIL, day 2 . | ATO, day 2 . | TRAIL plus ATO, day 2 . | |
| M1 (69) | 30 | 34 | 71 | 37 | 39 | 94 |
| M2 (41) | 17 | 33 | 69 | 38 | 47 | 95 |
| M3 (55) | 18 | 20 | 55 | 29 | 42 | 87 |
| M4 (36) | 30 | 26 | 70 | 42 | 45 | 92 |
| M5 (63) | 29 | 43 | 68 | 38 | 66 | 97 |
| M6 (77) | 20 | 46 | 77 | 44 | 64 | 99 |
Fresh myeloma cells were purified by flow sorting of CD38bright/CD45 bone marrow (BM) cells. Myeloma cells with a purity of more than 95% were obtained.33Sorted cells were cultured for 2 days with 4 μM ATO and/or 100 ng/mL APO2/TRAIL.
Apoptosis was determined by the annexin V method in cells treated with APO2/TRAIL alone, ATO alone, or with both drugs.
MI through M6 represent myeloma cells sorted from the BM of 6 MM patients. Background apoptosis in nontreated cells was less than 10%.