CD274 and non-small cell lung carcinoma: KPNB1 knockdown significantly reduced nuclear PD-L1 protein levels in PC9R and A549R cells (Figure 5d), whereas KPNB1 overexpression increased nuclear PD-L1 levels (Figure 5e), indicating that KPNB1 facilitates PD-L1 nuclear entry in radiation-resistant NSCLC cells.