Screening of NPC-related circRNAs in GSE143797. (A, B) Hierarchical clustering analysis and volcano plots for significantly differentially expressed circRNAs in tumorous or adjacent normal tissues for NPC patients (N = 5). (C) Relative expression of 5 upregulated circRNAs in NPC tissues (n=8). (D) Schematic of hsa_circ_0081534. (E) hsa_circ_0081534 was assessed by use of divergent primer sets and amplified in cDNA but did not amplify by use of these primer sets in gDNA. (F) Levels of hsa_circ_0081534 were detected in NPC cells treated with RNase R, and for NPC cells not treated with RNase R. *P < 0.05.