MDK and neoplasm: As shown in Figure 6B, strong membrane staining (IHC 3+) was observed in the NIH/3 T3 cells expressing MDK-HER2 or ZNF207-HER2, similar to the results observed in the original primary tumor samples (Figure 4D), thus further supporting the inability of ZNF207-HER2 to bind to T-DM1.