Fig. 7

Proposed mechanism that TGM2 may regulate PD-L1 expression via STAT3/NF-κB signaling pathways in PDAC. a Correlation analysis of TGM2 and immunosuppressive factors with TIMER. b Correlation analysis of TGM2 and CD274 (PD-L1) by TIMER. c, d Western blot results showed that TGM2 knocking down resulted in a decreased expression of PD-L1 and p-STAT3 in PANC-1 and Mia PaCa-2 cells. e TGM2 knocking down in PANC-1 cells led to a decreased expression of p-Akt (Ser473) and p-P65 (Ser536) which was consistent with previous studies. f TGM2 may regulate PD-L1 via NF-κB/STAT3 signaling pathways: a TGM2 activated AKT pathway and then promotes the activation of downstream transcription factor NF-κB which has been reported to be able to directly bind with the promoter of PD-L1 and stimulate its transcription. b TGM2 may promote the phosphorylation of STAT3 despite the underlying pathways remains unclear, and then p-STAT3 binds to the promoter of PD-L1 and stimulate its transcription