Fig. 4.

Efficient HER2-ECD overexpression in human cancer cell lines by a recombinant replication-deficient adenovirus vector. a Western blot analysis of HER2-wt (185 kDa), HER2-ECD (100 kDa), and representative HER2-related signaling proteins in various types of human cancer cells. Trastuzumab-resistant breast cancer cells (SKBR3 and BT474), low HER2-expressing breast cancer cells (MCF7 and MDA-MB-231), and low HER2-expressing gastric cancer cells (MKN1 and MKN28) were infected with replication-deficient adenoviral vector expressing exogenous HER2-ECD (Ad-HER2-ECD) or replication-deficient control adenovirus (dl312) at an MOI of 20 for 36 h. b Flow cytometric analysis of HER2 expression and the amount of bound trastuzumab in cells 36 h after Ad-HER2-ECD infection at an MOI of 20