Viral proteins expression. Expression of E1A (a) was assayed in T47D and MDA-MB-23) cells. Cells were infected with Ad5AMUCH_RSV-NIS at multiplicity of infection (MOI) 20, and extracts were prepared at 24 hours after infection and compared with extracts from noninfected cells. (b) Hexon expression was assayed in MDA-MB-231 and T47D 48 hours after infection and compared with uninfected cells. HEK 293 cells infected with Ad5AMUCH_RSV-NIS were used as control.