CD274 and non-small cell lung carcinoma: To confirm the involvement of PI3K/Akt and MAPK pathways in MUC3A-mediated PD-L1 modulation, specific inhibitors of MEK, GSK1120212 (trametinib), and pan type I PI3Ks, GDC-0941 (pictilisib), were used to treat NSCLC cells (Fig. 3E).