ATG5 and nasopharyngeal carcinoma: Additionally, we used siRNA against ATG5 or Beclin 1 (BECN1) to inhibit autophagy initiation, and also observed that both siRNAs reversed the downregulation of SQSTM1 in the ANXA1 KD NPC cells, but only had slight effect on SQSTM1 levels in the scramble shRNA control NPC cells (Fig. 1d).