NAP1L1 and pancreatic neuroendocrine neoplasm: NAP1L1, the human counterpart of the yeast NAP-1 protein, and a kind of histone-binding factor involved in cumulative nucleosome formation, has been testified to be a potential tumor promoter and participates in the pathogenesis of a variety of tumors, including colorectal cancer, renal carcinoma and pancreatic neuroendocrine neoplasms [21–23].