CXCR4 and non-small cell lung carcinoma: Another study characterized CD133+ CXCR4+ metastasis-initiating cells (MICs) in NSCLC for potentially evading the immune surveillance through overexpression of PD-L1 and ectoenzymes CD73/CD38, which further facilitate the extracellular adenosine production, contributing to an immunosuppressive microenvironment [358].