When comparing transduction through the tumor marker-specific adapters, we observed that transduction through EpCAM was lower for the ΔRGD virus in all tumor cell lines as well as in both fibroblast cell lines (P < 0.0001 for the effect of the ΔRGD modification on EpCAM-retargeted virus across all tested cell lines, vs. P = 0.0002 for the decreased activity of the ΔRGD modification on non-retargeted virus). The gene discussed is EPCAM; the disease is neoplasm.