In vitro evaluation of targeted antisense 177Lu radiotherapy

Anticancer Res. 2011 Oct;31(10):3143-9.

Abstract

Background: The BCL2 proto-oncogene in non-Hodgkin's lymphoma is a dominant inhibitor of apoptosis. The goal of this work was to develop a (177)Lu-labeled anti-BCL2-peptide nucleic acid (PNA) conjugate designed for dual modality NHL therapy, i.e., simultaneous down-regulation of BCL2-mediated resistance to apoptosis and delivery of cytotoxic internally emitted radiation.

Materials and methods: The effect of 1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetra-acetic acid (DOTA)-anti-BCL2-Tyr(3)-octreotate was evaluated by uptake, efflux, proliferation, and viability assays, using Mec-1 lymphoma cells. In vitro dosimetry was modeled with a Monte Carlo projection.

Results: Cellular efflux indicated moderate retention of radioactivity in the Mec-1 cells. Viability studies using the (177)Lu-labeled PNA conjugate indicated a mass-dose dependence and strongly additive statistical effect in reducing cellular viability.

Conclusion: These studies demonstrate the ability of a BCL2 antisense PNA conjugate to specifically target, be retained in, and reduce cellular viability in Mec-1 NHL cells. The results also hold promise for the development of a therapeutic radiopharmaceutical with potential dual modality function.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Chromatography, High Pressure Liquid
  • Chromatography, Reverse-Phase
  • Humans
  • Lutetium / therapeutic use*
  • Molecular Targeted Therapy / methods*
  • Octreotide / analogs & derivatives
  • Octreotide / chemistry
  • Octreotide / pharmacology
  • Organometallic Compounds / chemistry
  • Organometallic Compounds / pharmacology
  • Peptide Nucleic Acids / pharmacology*
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Radioisotopes / therapeutic use*
  • Radiometry
  • Radiotherapy / methods*

Substances

  • MAS1 protein, human
  • Organometallic Compounds
  • Peptide Nucleic Acids
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins c-bcl-2
  • Radioisotopes
  • Lutetium
  • lutetium Lu 177 dotatate
  • Octreotide