Breast cancer metastasis suppressor 1 (BRMS1) was identified by differential display comparing metastasis-suppressed chromosome 11 hybrids with metastatic, parental MDA-MB-435 human breast carcinoma cells [4], and BRMS1 has subsequently been shown to suppress metastasis, but not tumorigenicity, of human melanoma and ovarian cancer cells in nude mice [5], [6]. This evidence concerns the gene BRMS1 and breast carcinoma.