Figure 3. The efficacy of anti-β₂M mAbs and BTZ combination treatment in β₂M-knockdown and β₂M-overexpression MM cells.

Non-specific (sh-con) or β₂M shRNA (sh-β₂M)-expressing, and stable control vector (con) or human β₂M cDNA (β₂M)-expressing ARP-1 (A and B) and MM.1S (C and D) cells were cultured in medium with or without addition of BTZ (5 nM) or anti-β₂M mAbs (10 μg/mL), singly or in combination for 24 hours. Apoptosis was reduced in β₂M shRNA-expressing ARP-1 (A) and MM.1S (C) cells receiving combination treatment compared with cells treated with BTZ only. Apoptosis was enhanced in β₂M-overexpressing ARP-1 (B) and MM.1S (D) cells receiving combination treatment, compared with cells treated with BTZ only. Summarized data from three independent experiments are shown. *P < 0.05, **P < 0.01.