CTSB and cancer: As shown by immunohistochemical analysis, 78 of 168 (46.5 %) paraffin-embedded HCC tissues showed weak or negative staining of CTSB protein, while 50 of 168 (29.8 %) HCC tissues showed mainly moderate CTSB staining (in the membrane and cytoplasm of cancer cell), and 40 of 168 (23.7 %) showed strong staining in tumor cells.