Overall, this integrated and systematic analysis of a large human insulinoma cohort, focused on non-MEN1 insulinomas, reveals a near-universal preponderance of mutations in, and differential expression of, epigenetic modifying genes and their targets, together with structural and CpG methylation alterations of the key imprinted region on chromosome 11 (Fig. 6). This evidence concerns the gene MEN1 and pancreatic insulinoma.