Fig. 2

Addiction of MM cells to DNA ligase III. a Left panel: immunoblot of LIG3 performed on plasmacells from MM cell lines and patients (Pts) compared to peripheral blood mononuclear cells (PBMCs) collected from healthy donors. GAPDH was used as a loading control. Right panel: immunofluorescence analysis showing subcellular distribution of LIG3 in AMO1 and patient (Pt#2) MM cells. b Left panel: indicated MM cell lines were transfected with either scramble control or LIG3-siRNA clone #2. CTG assay was performed 96 h from transfection. Results are expressed as percentage of siR-NC-transfected cells. Right panel: LIG3 knockdown was confirmed by western blot analysis 48 h after transfection. c Left panel: AMO1 cells were transduced with IPTG inducible CTRL-shRNA or LIG3-shRNA lentiviral particles as described above. CTG assay was peformed 6 days from IPTG induction (Top). LIG3 knockdown was confirmed by Western blotting 4 days from IPTG induction (Bottom). Rigth panel: inducible IPTG CTRL-shRNA or LIG3-shRNA AMO1 cells were injected s.c. into SCID/NOD mice. Averaged tumor volume of each group ± SD and LIG3 protein knockdown from a representative AMO1 xenograft per group, are shown. *p < 0.05; **p < 0.01