Consequently, we overexpressed different fluorescent protein-tagged STIM1 variants, including SIMT1-wild-type (WT)-enhanced green fluorescent protein (EGFP), STIM1-D76A-EGFP (constitutively active), and STIM1-D76A-ΔERM-enhanced yellow fluorescent protein (EYFP) (dominant negative) in U2OS osteosarcoma cell lines to further investigate whether cancer cell migration can be affected by manipulating SOCE levels through STIM1 activity. Here, STIM1 is linked to cancer.