Both the cell lines do express CD46 receptor but the infection ability and the relatively higher expression of viral genes at transcript and protein level including BNiP3 could be due to various cellular factors involved in the progression of viral infection providing favorable environment and better sensitivity to MDA-MB-231 cells toward rMV-BNiP3 as compared to MCF-7 cells. The gene discussed is BNIP3; the disease is viral infectious disease.