Development of anti-somatostatin receptors CAR T cells for treatment of neuroendocrine tumors

J Immunother Cancer. 2022 Jun;10(6):e004854. doi: 10.1136/jitc-2022-004854.

Abstract

Background: Neuroendocrine tumors (NETs) overexpress somatostatin receptors (SSTRs).

Methods: We developed a second-generation, ligand-based, anti-SSTR chimeric antigen receptor (CAR) incorporating the somatostatin analog octreotide in its extracellular moiety.

Results: Anti-SSTR CAR T cells exerted antitumor activity against SSTR+NET cell linesin vitro. The killing activity was highly specific, as demonstrated by the lack of CAR T cell reactivity against NET cells engineered to express mutated variants of SSTR2/5 by CRISPR/Cas9. When adoptively transferred in NSG mice, anti-SSTR CAR T cells induced significant antitumor activity against human NET xenografts. Although anti-SSTR CAR T cells could recognize the murine SSTRs as shown by their killing ability against murine NET cells, no obvious deleterious effects on SSTR-expressing organs such as the brain or the pancreas were observed in mice.

Conclusions: Taken together, our results establish anti-SSTR CAR T cells as a potential candidate for early phase clinical investigations in patients with NETs. More broadly, the demonstration that a known peptide drug can direct CAR T cell targeting may streamline the potential utility of multiple peptide motifs and provide a blueprint for therapeutic applications in a variety of cancers.

Keywords: T-lymphocytes; cell engineering; gastrointestinal neoplasms; immunotherapy; receptors, chimeric antigen.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Humans
  • Ligands
  • Mice
  • Nerve Tissue Proteins / metabolism*
  • Neuroendocrine Tumors* / drug therapy
  • Octreotide
  • Somatostatin / therapeutic use

Substances

  • Ligands
  • Nerve Tissue Proteins
  • cocaine- and amphetamine-regulated transcript protein
  • Somatostatin
  • Octreotide