Since the expression of Smurf2 was found to be elevated in human breast cancer cell lines and is involved in the proliferation and migration of breast cancer cells via interaction with CNKSR2, we investigated its role in the advancement of breast cancer by examining the expression along with CNKSR2 in an in vitro breast cancer progression model comprising MCF10A, MCF10AT, MCFDCIS, MCF-7 and MDA-MB-231. The gene discussed is CNKSR2; the disease is breast cancer.