In this clinical study, we hypothesized that epigenetic reprogramming through the administration of a low-dose DNA methyltransferase inhibitor, 5-azacytidine (5-aza), can improve tumor antigenicity through epigenetic modulation of immune suppressive cells and the reexpression of epigenetically silenced HLA class I APM components and/or immunogenic tumor antigens (TAs) to improve clinical outcomes upon rechallenge with immune checkpoint blockade (ICB). Here, ANPEP is linked to neoplasm.