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Oligonucleotide biological activity: relationship to the cell cycle and nuclear transport

S Wu-Pong1, J Bard, J Huffman

  • 1School of Pharmacy, Virginia Commonwealth University, Richmond 23298, USA.

Biology of the Cell
|July 1, 1997
PubMed

Insights

Oligodeoxynucleotide (ODN) uptake by cancer cells depends on the cell cycle. Cytosolic ODN levels, not total uptake, correlate with antisense activity, suggesting targeted cytoplasmic delivery is key.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Pharmacology

Background:

  • Oligodeoxynucleotide (ODN) cellular uptake is reportedly cell cycle-dependent.
  • This dependency has potential implications for cancer cell targeting strategies.

Purpose of the Study:

  • To investigate the relationship between the cell cycle, ODN uptake, intracellular transport, and antisense activity.
  • To understand ODN transport mechanisms and their impact on therapeutic efficacy.

Main Methods:

  • Used synchronized Rauscher erythroleukemia cells (chemical/flow cytometry).
  • Examined ODN uptake via subcellular fractionation and confocal microscopy.
  • Measured c-myc protein levels using Western blot analysis.

Main Results:

  • Cell cycle phase influenced intracellular ODN distribution and uptake extent, but not the uptake mechanism.
  • Antisense ODN activity correlated positively with cytosolic ODN levels and negatively with total cellular uptake.
  • Cytosolic ODN retention, not total uptake, was critical for antisense ODN activity.

Conclusions:

  • Cell cycle influences ODN uptake and distribution.
  • Cytosolic localization of ODN is more critical for antisense activity than total cellular uptake.
  • Novel strategies for direct cytoplasmic drug delivery may be beneficial.

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