Therefore, this study systematically elucidated that the ER-associated circular RNA circFAM13B enhances the interaction between the RBM3 protein and the precursor uXBP1 mRNA of key signaling molecules in ER, promoting its degradation, resulting in reduced nuclear entry of the transcription factor sXBP1, and subsequently inhibiting the cytokine CST6 transcription, thus suppressing invasion, metastasis, and lymphatic vessel formation in NPC cells (Fig. 8H). This evidence concerns the gene CST6 and nasopharyngeal carcinoma.