Proteins associated with tumor regression including granzyme A (GZMA) and Th1 markers such as the C-X-C motif chemokine ligand family (CXCL9, CXCL10, CXCL11) and interferon gamma (IFNG) mirrored the checkpoint inhibitor decreases seen in tissue during single agent pembrolizumab therapy. Here, CXCL9 is linked to neoplasm.