Relative expression of transient receptor potential cation channel subfamily V member 6 (TRPV6) was significantly upregulated by inecalcitol in all BC cell lines, while expression of catalase (CAT), solute carrier family 37 member 2 (SLC37A2), and insulin like growth factor binding protein 3 (IGFBP3) was induced in most but not all BC cell lines. The gene discussed is TRPV6; the disease is breast cancer.