SSTR2 and neuroendocrine neoplasm: Successful up-regulation of SSTR2 was demonstrated in various neuroendocrine tumor cell lines and tumor models through attenuation of DNA methylation by treatment with DNA-N-methyltransferase (DNMT) inhibitors and via increase in histone acetylation levels by treatment with histone deacetylase (HDAC) inhibitors 16-27.