Nitric Oxide Synthase Inhibition Prevents Cell Proliferation in Glioblastoma

J Mol Neurosci. 2023 Dec;73(11-12):875-883. doi: 10.1007/s12031-023-02166-3. Epub 2023 Oct 16.

Abstract

Glioblastoma multiforme (GBM) is a prevalent and aggressive primary brain tumor, presenting substantial treatment challenges and high relapse rates. GBM is characterized by alterations in molecular signaling and enzyme expression within malignant cells. This tumor exhibits elevated nitric oxide (NO.) levels. NO. is a crucial signaling molecule involved in the regulation of neuronal functions, synaptic transmission, and cell proliferation. It is primarily synthesized from L-arginine by nitric oxide synthase (NOS) enzymes. The increased levels of NO. in GBM stem from dysregulated activity and expression of clinically relevant NOS isoforms, particularly inducible NOS (iNOS) and neuronal NOS (nNOS). Based on this knowledge, we hypothesize that targeted pharmacological intervention with N6-(1-iminoethyl)-L-lysine (L-NIL), an iNOS inhibitor, and 7-Nitroindazole (7-NI), an nNOS inhibitor, may suggest a promising therapeutic strategy for the treatment of GBM. To test our hypothesis, we utilized the U87-MG cell line as an in vitro model of GBM. Our results showed that treatment with L-NIL and 7-NI led to a reduction in NO. levels, NOS activity, and clonogenic proliferation in U87-MG cells. These findings suggest that NO. and NOS enzymes might be prospective therapeutic targets for GBM.

Keywords: 7-NI; Glioblastoma multiforme; L-NIL; Nitric oxide; Nitric oxide synthase; Treatment.

MeSH terms

  • Cell Proliferation
  • Enzyme Inhibitors / pharmacology
  • Glioblastoma* / drug therapy
  • Humans
  • Neoplasm Recurrence, Local
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase / metabolism
  • Nitric Oxide Synthase Type I / metabolism
  • Nitric Oxide Synthase Type II / genetics
  • Nitric Oxide Synthase Type II / metabolism

Substances

  • Enzyme Inhibitors
  • Nitric Oxide Synthase
  • Nitric Oxide Synthase Type I
  • Nitric Oxide Synthase Type II
  • Nitric Oxide