Epigenetic potentiation of somatostatin-2 by guadecitabine in neuroendocrine neoplasias as a novel method to allow delivery of peptide receptor radiotherapy

Crown Copyright © 2022. Published by Elsevier Ltd. All rights reserved..

BACKGROUND: Somatostatin receptor-2 (SSTR2) is expressed on cell surface of neuroendocrine neoplasias; its presence is exploited for the delivery of peptide receptor radionuclide therapy (PRRT). Patients with no or low expression of SSTR2 are not candidates for PRRT. SSTR2 promotor undergoes epigenetic modification, known to regulate gene expression. We investigated whether the demethylation agent, guadecitabine, could enhance the expression of SSTR2 in NET models, using radioligand uptake/PET imaging as a biomarker of epigenetic modification.

METHODS: The effects of guadecitabine on the transcriptional, translational, and functional regulation of SSTR2 both in vitro and in vivo using low (QGP-1) and high (BON-1) methylated neuroendocrine neoplasia models was characterised. Promotor region methylation profiling of clinical samples (n = 61) was undertaken. Safety of combination guadecitabine and PRRT was assessed in vivo.

RESULTS: Pyrosequencing of cell lines illustrated differential methylation indices - BON: 1 94%, QGP: 1 21%. Following guadecitabine treatment, a dose-dependent increase in SSTR2 in BON-1 at a transcriptional, translational, and functional levels using the SSTR2-directed radioligand, 18F-FET-βAG-TOCA ([18F]-FETO) (150% increase [18F]-FETO uptake, p < 0.05) was observed. In vivo, guadecitabine treatment resulted in a 70% increase in [18F]-FETO uptake in BON-1 tumour models compared models with low baseline percentage methylation (p < 0.05). No additive toxicity was observed with the combination treatment of PRRT and guadecitabine in vivo. Methylation index in clinical samples was 10.5% compared to 5.2% in controls (p = 0.03) and correlated with SSTR2 expression (Wilcoxon rank sign -3.75,p < 0.01).

CONCLUSION: Guadecitabine increases SSTR2 expression both in vitro and in vivo. The combination of demethylation agents with PRRT warrants further investigation.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:176

Enthalten in:

European journal of cancer (Oxford, England : 1990) - 176(2022) vom: 01. Nov., Seite 110-120

Sprache:

Englisch

Beteiligte Personen:

Evans, Joanne S [VerfasserIn]
Beaumont, Jamie [VerfasserIn]
Braga, Marta [VerfasserIn]
Masrour, Nahal [VerfasserIn]
Mauri, Francesco [VerfasserIn]
Beckley, Alice [VerfasserIn]
Butt, Shamus [VerfasserIn]
Karali, Christina S [VerfasserIn]
Cawthorne, Chris [VerfasserIn]
Archibald, Stephen [VerfasserIn]
Aboagye, Eric O [VerfasserIn]
Sharma, Rohini [VerfasserIn]

Links:

Volltext

Themen:

2KT4YN1DP7
51110-01-1
Azacitidine
Epigenetic modification
Guadecitabine
Journal Article
M801H13NRU
Neuroendocrine tumours
Octreotide
Peptide receptor radionuclide therapy
RWM8CCW8GP
Receptors, Somatostatin
Research Support, Non-U.S. Gov't
SSTR2
Somatostatin

Anmerkungen:

Date Completed 21.11.2022

Date Revised 08.02.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.ejca.2022.09.009

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM347238467