Fig. 5

The proposed working model of niclosamide improves anti-PD-1 efficacy. Schematic diagram of the mechanism: niclosamide disrupts the nucleo-cytoplasmic shuttling of HuR, thereby inhibiting the posttranscription of PD-L1 mRNA and restraining PD-1/PD-L1-mediated tumor immune evasion. In addition, niclosamide abolishes the glycosylation and maturation of PD-L1, thus leading to the decrease of functional PD-L1 form. Therefore, blocking HuR nucleocytoplasmic translocation and PD-L1 glycosylation by niclosamide can reverse the immunotherapy suppression and enhance anti-PD-1 efficacy