Moreover, circTLCD4-RWDD3-mediated UBC9 overexpression promoted SUMO2 modification on K108 residue of hnRNPA2B1, which interacted noncovalently with the SIM on ALIX to load circTLCD4-RWDD3 into EVs derived from NSCLC cells. Here, SUMO2 is linked to non-small cell lung carcinoma.