HPRT1 and cholangiocarcinoma: HPRT1 activity was higher in the tumor groups of BLCA, BRCA, CESC, cholangiocarcinoma (CHOL), COAD, ESCA, GBM, HNSC, KICH, KIRC, KIRP, LIHC, LUAD, LUSC, PRAD, READ, sarcoma (SARC), STAD, THCA, and UCEC (Figure 1D).