MTA3 depletion is associated with differentiation of DLBCL cells. (A) MTA3 Immunoblots were performed in LY1 and SUDHL4 DLBCL cell lines—actin is shown as loading control. (B) Immunoblots for MTA3, PRDM1, and actin performed in Ly1 cells (left) and SUDHL4 cells (right) transfected with MTA3 siRNA or ctrl siRNA. (C) MTA3 siRNA knockdown was performed in Ly1 (left panel) and SUDHL4 cells (right panel), followed in 24 hours by QPCR for the MTA3, PRDM1, SDC1, TP53, and ATR transcripts. The y-axis represents the fold change in mRNA abundance relative to the levels in wild-type and control siRNA–transfected cells. Error bars are SD. (D) Dual immunofluorescence of a human tonsillar GC with MTA3 (red) and PRDM1 (green) antibodies. The inset is the same GC at low-power magnification. (E) Ly1 cells were transfected with MTA3 or control siRNA and examined by immunohistochemistry for expression of MTA3, PRDM1, and κ light chains with corresponding antibodies.