CTSB and neoplasm: CTSB-shRNA treated tumor did not show significantly higher percentage of TUNEL-positive nuclei than tumors treated with PBS, Lipo, or NC group (6 ± 1.3 versus 6 ± 1, 7 ± 1.5, or 7.5 ± 1.6, 6 ± 1.6, P > 0.05).