Potent Antitumour Effects of Novel Pentabromobenzylisothioureas Studied on Human Glial-derived Tumour Cell Lines

Anticancer Res. 2018 May;38(5):2691-2705. doi: 10.21873/anticanres.12511.

Abstract

Background/aim: Tumours of astroglial origin are the most common primary brain malignancy characterized by infiltrative growth and resistance to standard antitumour therapy. Glioma progression is thought to be related to various intracellular signal transduction pathways that involve the activation of protein kinases. Protein kinases play important roles in cell differentiation, proliferation, and survival. Recently, novel, specific inhibitors of constitutively active serine/threonine kinases and structurally similar isothiourea derivatives were suggested to induce apoptosis and inhibit proliferation in several types of human cancer cells.

Materials and methods: In this study, we examined the cytotoxic and proapoptotic activities of selected modified pentabromobenzyl isothioureas (ZKKs) in an adult human glioblastoma (T98G) and a subependymal giant cell astrocytoma cell (SEGA) line. We evaluated cell proliferation, viability, and apoptosis.

Results: Two pentabromobenzyl isothiourea bromide derivatives, ZKK-13 and N,N,N'-trimethyl-ZKK1 (TRIM), exhibited the most potent cytotoxic and proapoptotic efficacies against human glioma-derived cells, even at a very low concentration (1 μM). ZKK-13 (25-50 μM) inhibited cell growth by approximately 80-90% in 24 and 48 h of treatment. We showed that selected ZKKs exerted antiproliferative activity against astroglial neoplastic cells of both low- and high-grade tumour malignancy classes. No synergistic effects were detected when ZKKs were combined with serine/threonine kinase inhibitors.

Conclusion: Our findings indicated that modified ZKKs show promise for the treatment of glioma-derived brain tumours.

Keywords: Protein kinase inhibitors; anticancer therapy; apoptosis; gliomas; pentabromobenzyl isothioureas.

MeSH terms

  • Adult
  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects
  • Astrocytes / pathology*
  • Astrocytoma / pathology
  • Brain Neoplasms / pathology
  • Casein Kinase II / antagonists & inhibitors
  • Cell Division / drug effects
  • Cell Line, Tumor
  • Drug Screening Assays, Antitumor
  • Glioblastoma / pathology
  • Humans
  • Isothiuronium / analogs & derivatives*
  • Isothiuronium / chemical synthesis
  • Isothiuronium / pharmacology
  • Molecular Targeted Therapy
  • Neoplasm Proteins / antagonists & inhibitors
  • Protein Kinase Inhibitors / chemical synthesis
  • Protein Kinase Inhibitors / pharmacology*
  • Protein Serine-Threonine Kinases / antagonists & inhibitors
  • Thiourea / analysis*
  • Thiourea / chemistry
  • Thiourea / pharmacology*

Substances

  • Antineoplastic Agents
  • Neoplasm Proteins
  • Protein Kinase Inhibitors
  • ZKK-13
  • Isothiuronium
  • Casein Kinase II
  • Protein Serine-Threonine Kinases
  • Thiourea