However, the fact that Masitinib, which inhibits both PDGFRα and PDGFRβ as well as c-kit (similar to Imatinib), significantly inhibited migration of both human breast cancer cell lines, but had no effect on proliferation or apoptosis argues against the IC50 or other kinase targets limiting Imatinib’s efficacy. This evidence concerns the gene KIT and breast carcinoma.