It was observed that the tumor tissue of saline and soluplus group highly expressed HIF-1α (Figures 3A,B), and r-As4S4 administration mildly down-regulated HIF-1α expression with weak brown color staining in tumor tissue (Figure 3C), while much less HIF-1α was detected in the e-As4S4 group (Figure 3D). This evidence concerns the gene HIF1A and neoplasm.