GPR19 and colorectal carcinoma: Furthermore, immunofluorescence revealed that more adropin+ GPR19+ cells were present in the stroma of CRC biopsies than in normal tissues (Fig. 1M and O, and Supplementary Fig. 1) and more adropin+ GPR19+ cells were present in the stroma of metastatic CRC biopsies compared with in situ tumors (Fig. 1 N and 1P).