Epigenetic mechanisms, and the observed or predicted consequence of menin loss are shown that were investigated in various studies of human or mouse endocrine tumors, or studies conducted in endocrine/endocrine-related cell lines. Green or Red, indicates the normal effect of the epigenetic event resulting in the activation or repression of gene expression, respectively. Up or Down arrow, indicates increase or decrease, respectively, of the epigenetic event in a cell line or tumor with menin-deficiency. ALT (alternative lengthening of telomeres) is shown in blue (and not in red or green) because it is an event associated with chromatin structure at telomeres.