Abstract Library

#4124 Evaluating a possible association between promoter methylation level of genes encoding catecholamine metabolizing enzymes and metanephrine secretion in pheochromocytoma and paraganglioma

Introduction: Paragangliomas (PPGLs) are rare neuroendocrine tumors that may secrete catecholamines and their metabolites (metanephrines [MN], normetanephrine [NMN]). Secretion patterns differ by adrenal/extra-adrenal origin and genetic alteration. Catecholamines synthesis is carried by phenylalanine hydroxylase (PAH), tyrosine hydroxylase (TH), aromaticL-aminoacid decarboxylase (AADC), dopamine β-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT). However, their regulation in PPGL is not entirely understood.

Conference:

Presenting Author: Tirosh A

Authors: Kaplinsky A, Halperin R, Shlomai G, Tirosh A,

Keywords: ppgl, methylation, catecholamine, pseudohypokia, metanephrine, kinase signaling, pheochromocytoma, paraganglioima,

#4119 Interim analysis of LANTana: Phase Ib study investigating up-regulation of somatostatin receptor-2 (SSTR2) with the de-methylating agent ASTX727 to allow [177Lu]Lu-DOTA-TATE in metastatic neuroendocrine tumors (NETs)

Introduction: To be suitable for [177Lu]Lu-DOTA-TATE, SSTR2 must be present on tumor surface as per positive uptake on [68Ga]Ga-DOTA-TATE-PET/CT. SSTR2 promoter methylation reduces SSTR2 expression; this can be reversed using a demethylating agent.

Conference:

Presenting Author:

Authors: Rzeniewicz K, Ward C, Khan S, Naik M, Qurashi M,

Keywords: neuroendocrine tumor, peptide receptor radionucleotide therapy, methylation, [68Ga]Ga-DOTA-peptide-PET, [177Lu]Lu-DOTA-TATE,

#3804 Wide molecular analysis of PanNET revealed that only MGMT promoter methylation seemed to correlate with Temozolomide response

Introduction: Temozolomide (TMZ) is an alkylating agent and is widely used in the treatment of PanNET. So far, only the MGMT status, defined by its immunohistochemical (IHC) expression or its promoter methylation, has been proposed as predictor of response to TMZ, but its value remains controversial.

Conference:

Presenting Author: Marinoni I

Authors: Cives M, Kirchner P, Palmirotta R, Lauricella E, de Mestier L,

Keywords: PanNET, Temozolomide, MGMT,

#3796 The effect of pseudohypoxia on the immune microenvironment of pancreatic neuroendocrine neoplasms (PanNEN)

Introduction: Pancreatic neuroendocrine tumors may develop sporadically or as part of an inherited disease, such as von Hippel-Lindau (VHL). VHL disease is caused by a germline pathogenic variant in the VHL gene encoding VHL protein (pVHL). Hypoxia inducible factor (HIF) is responsible for cellular oxygen supply. Its degradation is mediated in normoxic states via ubiquitination and inhibited by pVHL. Hence, pVHL deficiency leads to pseudohypoxia due to HIF overexpression. Several studies suggested immunomodulatory role for HIF in kidney cancer.

Conference:

Presenting Author:

Authors: Solomon Chmelnik A, Telerman A, Tirosh A,

Keywords: Pancreatic neuroendocrine tumor, VHL, DNA methylation, Immune cells, PD-L1,

#976 Upregulation of Somatostatin Receptor Type 2 Expression in Neuroendocrine Tumors by Epigenetic Modulation

Introduction: The somatostatin receptor type 2 (sst2) is a target for treatment of neuroendocrine tumors (NETs). However, epigenetic mechanisms might account for the high variability in sst2 expression and treatment response between patients.

Conference: 11th Annual ENETSConcerence (2014)

Presenting Author:

Authors: Veenstra M, Van Koetsveld P, Farrell W, Dogan F, Waaijers A,

Keywords: GEP-NET, sst2, epigenetics,