Representative immunohistochemical staining of CXCR4 expression in a human PDAC patient was presented in Fig. 1A; inset, higher magnification demonstrates cytoplasmic CXCR4 being negative in tumor cells, and positive in stromal cells and inflammatory cells (lymphocytes) (Fig. 1A1, 1A2, 1A3, respectively). This evidence concerns the gene CXCR4 and neoplasm.