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Implementation of In Vitro Drug Resistance Assays: Maximizing the Potential for Uncovering Clinically Relevant Resistance Mechanisms
08:46

Implementation of In Vitro Drug Resistance Assays: Maximizing the Potential for Uncovering Clinically Relevant Resistance Mechanisms

Published on: December 9, 2015

Proteomic evidence for roles for nucleolin and poly[ADP-ribosyl] transferase in drug resistance

Zongming Fu1, Catherine Fenselau

  • 1Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA.

Journal of Proteome Research
|October 11, 2005
PubMed

Insights

This study identified 14 altered proteins in drug-resistant breast cancer cells, revealing decreased cytoskeleton proteins and PARP-1. Specific proteins like nucleolin and BUB3 showed altered abundance in distinct resistant lines.

Area of Science:

  • Proteomics
  • Cancer Biology
  • Cellular Biochemistry

Background:

  • MCF-7 human breast cancer cells are a common model for studying cancer.
  • Drug resistance is a major challenge in cancer therapy, necessitating the identification of underlying molecular mechanisms.
  • Understanding proteomic changes in resistant cells can reveal new therapeutic targets.

Purpose of the Study:

  • To identify proteins with altered abundance in MCF-7 cells resistant to etoposide, mitoxantrone, or adriamycin/verapamil.
  • To compare proteomic profiles across different drug resistance mechanisms.
  • To uncover potential biomarkers or therapeutic targets associated with multidrug resistance.

Main Methods:

  • Proteomic analysis of soluble nuclear proteins from parental and drug-resistant MCF-7 cell lines.
  • Quantitative gel electrophoresis and stable isotope labeling techniques were employed.
  • Identification of proteins with greater than 2-fold abundance changes.

Main Results:

  • One hundred twenty-four nuclear proteins were identified in parental MCF-7 cells.
  • Fourteen proteins showed altered abundance (>2-fold) in at least one resistant cell line.
  • Common alterations included decreased abundance of cytoskeleton proteins (cytokeratin 8, cytokeratin 19, septin 2, alpha tropomyosin) and poly(ADP-ribosyl)transefrase (PARP-1).
  • Nucleolin abundance increased in etoposide- and mitoxantrone-resistant lines.
  • BUB3 (mitotic checkpoint protein) increased in the adriamycin/verapamil-resistant line.

Conclusions:

  • Drug resistance in breast cancer cells is associated with significant proteomic alterations, particularly in cytoskeletal components and DNA repair proteins.
  • Specific protein changes correlate with distinct drug resistance profiles.
  • These findings may provide insights into mechanisms of multidrug resistance and suggest potential targets for overcoming it.

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