Putative GPR15 co-expressed genes, such as TACR1, TAS2R9, SPDYE4, or GPR182, could be a more specific sign for tumor cells of adenocarcinoma or for healthy epithelial cells from which the tumor originates since all four genes were not expressed in GPR15+CD3+ lymphocytes [4]. This evidence concerns the gene SPDYE4 and neoplasm.