A growth model of neuroendocrine tumor surrogates and the efficacy of a novel somatostatin-receptor-guided antibody-drug conjugate: Perspectives on clinical response?

Surgery. 2020 Jan;167(1):197-203. doi: 10.1016/j.surg.2019.04.073. Epub 2019 Sep 19.

Abstract

Background: As patient-derived xenografts and other preclinical models of neuroendocrine tumors for testing personalized therapeutics are lacking, we have developed a perfused, 3D bioreactor model to culture tumor surrogates from patient-derived neuroendocrine tumors. This work evaluates the duration of surrogate culture and surrogate response to a novel antibody-drug conjugate.

Methods: Twenty-seven patient-derived neuroendocrine tumors were cultured. Histologic sections of a pancreatic neuroendocrine tumor xenograft (BON-1) tumor were assessed for SSTR2 expression before tumor implantation into 2 bioreactors. One surrogate was treated with an antibody-drug conjugate composed of an anti-mitotic Monomethyl auristatin-E linked to a somatostatin receptor 2 antibody. Viability and therapeutic response were assessed by pre-imaging incubation with IR-783 and the RealTime-Glo AnnexinV Apoptosis and Necrosis Assay (Promega Corporation, Madison, WI) over 6 days. A primary human pancreatic neuroendocrine tumor was evaluated similarly.

Results: Mean surrogate growth duration was 34.8 days. Treated BON-1 surrogates exhibited less proliferation (1.2 vs 1.9-fold) and greater apoptosis (1.5 vs 1.1-fold) than controls, whereas treated patient-derived neuroendocrine tumor bioreactors exhibited greater degrees of apoptosis (13- vs 9-fold) and necrosis (2.5- vs 1.6-fold).

Conclusion: Patient-derived neuroendocrine tumor surrogates can be cultured reliably within the bioreactor. This model can be used to evaluate the efficacy of antibody-guided chemotherapy ex vivo and may be useful for predicting clinical responses.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Animals
  • Antineoplastic Agents, Immunological / pharmacology
  • Antineoplastic Agents, Immunological / therapeutic use
  • Apoptosis / drug effects
  • Bioreactors*
  • Cell Proliferation / drug effects
  • Drug Screening Assays, Antitumor / instrumentation*
  • Drug Screening Assays, Antitumor / methods
  • Humans
  • Immunoconjugates / pharmacology*
  • Immunoconjugates / therapeutic use
  • Male
  • Mice
  • Molecular Targeted Therapy / methods
  • Neuroendocrine Tumors / drug therapy*
  • Neuroendocrine Tumors / pathology
  • Oligopeptides / pharmacology
  • Oligopeptides / therapeutic use
  • Pancreatic Neoplasms / drug therapy*
  • Pancreatic Neoplasms / pathology
  • Primary Cell Culture / instrumentation*
  • Primary Cell Culture / methods
  • Receptors, Somatostatin / antagonists & inhibitors
  • Reproducibility of Results
  • Tumor Cells, Cultured

Substances

  • Antineoplastic Agents, Immunological
  • Immunoconjugates
  • Oligopeptides
  • Receptors, Somatostatin
  • SSTR2 protein, human
  • monomethyl auristatin E