TRAIL sensitivity and NF-κB profile of HMCLs used in this study
| HMCLs . | ED50 of TRAIL, ng/mL . | NF-κB pathway . | NF-κB index . | NF-κB mutation . |
|---|---|---|---|---|
| OPM-2 | 4.7 ± 0.9 | Weak canonical | 9.03 | — |
| RPMI 8226 | 4.8 ± 0.4 | Both canonical and noncanonical | 10.44 | TRAF3 |
| U266 | 55.2 ± 6.8 | Both canonical and noncanonical | 10.41 | TRAF3 |
| RPMI 8226/R5 | 50.2 ± 7.1 | Both canonical and noncanonical | ND | ND |
| JJN3 | >1000 | Both canonical and noncanonical | 10.80 | NIK |
| HMCLs . | ED50 of TRAIL, ng/mL . | NF-κB pathway . | NF-κB index . | NF-κB mutation . |
|---|---|---|---|---|
| OPM-2 | 4.7 ± 0.9 | Weak canonical | 9.03 | — |
| RPMI 8226 | 4.8 ± 0.4 | Both canonical and noncanonical | 10.44 | TRAF3 |
| U266 | 55.2 ± 6.8 | Both canonical and noncanonical | 10.41 | TRAF3 |
| RPMI 8226/R5 | 50.2 ± 7.1 | Both canonical and noncanonical | ND | ND |
| JJN3 | >1000 | Both canonical and noncanonical | 10.80 | NIK |
HMCLs were cultured in presence of escalating doses of TRAIL (0.6-2000 ng/mL). After 24 hours, cell death was measured by annexin-V staining, and the median effective dose (ED50, dose producing 50% of cytotoxicity) was estimated using the Median Effect Equation of Chou. Values represent mean ± SD of 4 independent experiments.
The contribution of the canonical and noncanonical NF-κB pathways in HMCLs was estimated from steady-state levels of NF-κB subunits and/or effect of IKK β inhibition on nuclear localization and DNA binding activity of the NF-κB p65 and p52 subunits.19,20 The NF-κB index was calculated using the average expression of 10 NF-κB target genes19 (Genes comprising the NF-κB index in myeloma). NF-κB mutations were previously reported.19,20 —, no mutation identified; ND, nondetected; NIK, NF-κB inducing kinase.