VSIR and cancer: For example, expression of EGFR was decreased in the eight cancer cell lines after transfection of siSp1, siSp3 and siSp4 and expression of all of gene products (EGFR, survivin, bcl-2 and VEGF) were decreased in cells transfected with siSp3 and siSp4 but variable responses were observed for siSp1 (Figures 3A–3D).