Table 3 shows several genes, whether activated or inactivated, that are thought to be the most important in the development of pancreatic cancer [23]. The mu-opioid receptor (MOR) and somatostatin receptor 2 (SSTR2) are unique receptors in PDAC or their malignant environment. Both receptors localize on the cellular membrane, and their activation leads to metastasis [24]. This evidence concerns the gene OPRM1 and familial pancreatic carcinoma.