Immunofluorescence staining of different thickness (2, 4, and 6 mm) of tumor tissue slices showed that tumors treated with PMNSG plus laser irradiation possessed significantly improvement of hypoxia reflected by HIF-1α expression and significant cell apoptosis reflected by caspase-3 expression even at 6 mm depth of tumor tissues (Fig. 6i–l and Supplementary Fig. 43). This evidence concerns the gene CASP3 and neoplasm.