RSU1 and breast cancer: In the present study, we evaluated the expression of both RSU-1 isoforms at the protein level and, as shown in Fig. 7, RSU-1L was dramatically upregulated in metastatic samples (Fig. 7a, compare lanes 4, 6 and 8 to 3, 5 and 7, as well as Fig. 7b), while RSU-1-X1 had the exact opposite expression pattern, being upregulated in in situ (Fig. 7a, compare lane 2 to 1, as well as Fig. 7c) and downregulated in metastatic BC samples (Fig. 7a, compare lanes 4, 6 and 8 to 3, 5 and 7 for RSU-1-X1, as well as Fig. 7c).