Relationships of PSMD4 expression levels, chromosome 1q21 copy number, and GEP80 risk scores. (A) Box plot of baseline PSMD4 expression level in normal donors (NLs) and in patients with multiple myeloma with 1q21 (CKS1B) DNA copy numbers of 2, 3, and ≥4 from interphase FISH experiment. The plot shows that PSMD4 expression levels were highly correlated with 1q21 (CKS1B) copy number (P < .0001). (B) Box plot of the GEP80(BL) score in normal donors (NLs) and in patients with multiple myeloma with 1q21 copy numbers of 2, 3, and ≥ 4, showing increased risk score with higher copy number. (C) Box plot of GEP80(BL) score in risk groups defined by GEP70 and GEP80(BL) models: low 70-gene risk/low 80-gene risk (LL), low 70-gene risk/high 80-gene risk (LH), high 70-gene risk/low 80-gene risk (HL), and high 70-gene risk/high 80-gene risk (HH). (D) Box plot of GEP80(PB) score in risk groups defined by GEP70 and GEP80(PB) models: low 70-gene risk/low 80-gene risk (LL), low 70-gene risk/high 80-gene risk (LH), high 70-gene risk/low 80-gene risk (HL), and high 70-gene risk/high 80-gene risk (HH). (E) PFS (left) and OS (right) in TT3 (UARK2003-33) according to the PSMD4 expression levels (low, medium, and high) corresponding to 1q21 (CKS1B) copy number (2, 3, and 4). Note the graded effect of increasing PSMD4 levels on shortening PFS and OS in the case of TT3. (F) PFS (left) and OS (right) in TT2 (UARK98-026) according to the PSMD4 expression levels (low, medium, and high) corresponding to 1q21 (CKS1B) copy number (2, 3, and 4). Only patients with low-tertile PSMD4 expression levels fare better.