BCL2 and nasopharyngeal carcinoma: As shown in Figure 5, knockdown of SIRT1 aggravated the cell proliferation inhibition and apoptosis in NPC cell lines (Figures 5A–F), as well as the Bax/Bcl-2 ratio (Figures 5G,H) and caspase 3 cleavage (Figures 5I,J).