Targeted killing of rhabdomyosarcoma cells by a MAP-based human cytolytic fusion protein

Cancer Lett. 2015 Sep 1;365(2):149-55. doi: 10.1016/j.canlet.2015.04.004. Epub 2015 Apr 14.

Abstract

The treatment of rhabdomyosarcoma (RMS) is challenging, and the prognosis remains especially poor for high-grade RMS with metastasis. The conventional treatment of RMS is based on multi-agent chemotherapy combined with resection and radiotherapy, which are often marked by low success rate. Alternative therapeutic options include the combination of standard treatments with immunotherapy. We generated a microtubule-associated protein (MAP)-based fully human cytolytic fusion protein (hCFP) targeting the fetal acetylcholine receptor, which is expressed on RMS cells. We were able to express and purify functional scFv35-MAP from Escherichia coli cells. Moreover, we found that scFv35-MAP is rapidly internalized by target cells after binding its receptor, and exhibits specific cytotoxicity toward FL-OH1 and RD cells in vitro. We also confirmed that scFv35-MAP induces apoptosis in FL-OH1 and RD cells. The in vivo potential of scFv35-MAP will need to be considered in further studies.

Keywords: Fetal acetylcholine receptor; Human cytolytic fusion protein; Immunotherapy; Microtubule-associated protein; Rhabdomyosarcoma.

MeSH terms

  • Apoptosis / drug effects*
  • Camptothecin / pharmacology
  • Cell Line, Tumor
  • Cholinergic Antagonists / pharmacology*
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Humans
  • Immunotherapy
  • Microtubule-Associated Proteins / genetics*
  • Protein Binding
  • Receptors, Cholinergic / metabolism
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / pharmacology*
  • Rhabdomyosarcoma / drug therapy*
  • U937 Cells

Substances

  • Cholinergic Antagonists
  • Microtubule-Associated Proteins
  • Receptors, Cholinergic
  • Recombinant Fusion Proteins
  • Camptothecin