PDCD1 and non-small cell lung carcinoma: To investigate the potential impact of genetic background on the efficiency of CIK cells, Li et al. cultured three genetically distinct NSCLC cell lines with distinct rearrangements (EML4-ALK, KRAS mutation, and ROS1 rearrangement) in combination with PD-1 and an anaplastic lymphoma kinase (ALK) inhibitor [13].