EGFR and lung carcinoma: As the PD-L1 proteins were reportedly overexpressed on selected lung cancer biopsy or surgical specimen from harboring sensitive EGFR mutations [23–25], it is possible that EGFR inhibitors can promote anti-tumor T cell responses in lung cancer via up-regulation of antigen presenting pathway while down-modulating PD-L1 expression in concurrent fashion as with skin keratinocytes.