We previously generated stable MDA-MB-231 breast cancer cells with doxycycline (dox)-inducible expression of thoroughly characterized camelid nanobodies targeting CTTN SH3 or NTA domain (CTTN SH3 Nb2 or CTTN NTA Nb212,26, respectively) or FSCN1 (FSCN1 Nb512,29). This evidence concerns the gene FSCN1 and breast cancer.