Knockdown of NHP2 reduces telomerase activity of PLC/PRF5 cells with or without HBx upregulation via interfering with TERT expression. (A) The telomerase activity of PLC/PRF5 cells with or without HBx upregulation in the absence or presence of NHP2 knockdown. (B) Representative western blot bands together with quantitative analysis for HBx and TERT expression in different groups of PLC/PRF5 cells. (C, D) The interaction between TERT and NHP2 was determined by co-immunoprecipitation assay. Ov: overexpression, NC: negative control, HBX: Hepatitis B virus X. *P<0.05, **P<0.01 and ***P<0.001.