ERBB2 and non-small cell lung carcinoma: Because HER2 is frequently overexpressed in EGFR-positive NSCLC and to some extent accounts for resistance to EGFR-targeted therapy [31], we attempted to utilize scFv-9R to deliver HER2 siRNA (HER2si) and examine their effect on EGFR-positive, HER2-overexpressed NSCLC.