PRNP and cancer: PrPC has been found to be upregulated or ectopically expressed in different types of cancer tissues, such as hepatocellular carcinoma, gastric cancer, melanoma, breast cancer, colorectal cancer, pancreatic ductal adenocarcinoma, prostate cancer, osteosarcoma, and glioblastoma [30,31,32,33,34,35,36,37,38,39].