TBK1 and hepatocellular carcinoma: For instance, circSOBP in glioma enhances NK cell killing function through the IKKε/TBK1/IRF3 signaling pathway by promoting interferon expression.[62] Furthermore, circUHRF1 in HCC exosomes has been shown to suppress NK cell IFN‐γ secretion, thereby weakening their antitumor activity.[63] In our study, we found that circSMPD4 does not affect the expression of NK‐cell‐related activating and inhibitory ligands on tumor cell surface, but rather indirectly inhibits NK cell cytotoxicity by increasing lactate production and export.