Recently, Meng et al. reported that in the human breast cancer cell line, p-moesin prevents PD-L1 from the ubiquitination that leads to the proteasomal degradation by competing with E3 ubiquitin ligase, thereby inhibiting degradation of PD-L1, which in turn stabilizes PD-L1 in the surface plasma membrane [64]. The gene discussed is MSN; the disease is breast carcinoma.