Among the pull‐downed proteins (Table S2, Supporting Information), circWDR37 was found to interact with double‐stranded RNA‐activated protein kinase R (PKR), a dsRNA sensor related to NF‐κB activation (Figure4a; Figure S4c, Supporting Information).[34] Western blot analysis following an RNA pull‐down assay further confirmed that the biotin‐labeled circWDR37 specifically bound to PKR in NPC cells, when compared with the antisense RNA (Figure 4b). The gene discussed is NFKB1; the disease is nasopharyngeal carcinoma.