Concerning the epigenetic biomarkers of response to ICB, we have recently reported the association of the methylation state of 301 CpGs that conform to the “EPIMMUNE” signature, and its subrogation to the unmethylated state of a single CpG of FOXP1, a transcription factor involved in the regulation of quiescent CD4+ cells, and the regulation of follicular T helper cells, with overall and progression-free survival to anti-PD-1 treatment in NSCLC patients [28]. The gene discussed is CD4; the disease is non-small cell lung carcinoma.