To confirm whether the inhibitory effect of NDRG2 overexpression on PD-L1 expression was related to the regulation of STAT3 or NF-κB activation in mouse breast cancer cells, we examined the phosphorylation levels of STAT3 and NF-κB in 4T1-mock and -NDRG2 cells. This evidence concerns the gene NFKB1 and breast carcinoma.