In the present study we explored the feasibility of using Ad-CD44-N-HIF3α4 to treat TNBC by in vitro and in vivo experiments using MDA-MB-231 a human TNBC cells and compared it’s in vivo anti-tumor activities with other adenovirus vectors, Ad-SOCS3 (30) and Ad-p53 (31). The gene discussed is CD44; the disease is neoplasm.