Analysis of human tumor and control tissue data from the TCGA and GTeX databases [34, 35] showed that the mRNA level of GPR81 (i.e. HCAR1) is increased or tends to be increased in many cancers, including pancreatic, ovarian, bladder, colon, and lung cancer, compared to the corresponding control tissue (Suppl. Here, HCAR1 is linked to neoplasm.