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Intracellular cargo delivery by an octaarginine transporter adapted to target prostate cancer cells through cell

Elena A Goun1, Rajesh Shinde, Karen W Dehnert

  • 1Department of Chemistry, Stanford University, Stanford, California 94305, USA.

Bioconjugate Chemistry
|May 18, 2006
PubMed

Insights

Researchers developed activatable protein-transduction domains (APTDs) that target prostate cancer. These molecules are selectively taken up by cancer cells only after cleavage by prostate-specific antigen (PSA), enabling targeted delivery.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Drug Delivery

Background:

  • Targeted delivery of therapeutics and imaging agents requires molecular specificity.
  • Cell-associated proteases offer potential for activation strategies in pathological conditions.
  • Prostate-specific antigen (PSA) is an extracellular protease linked to prostate cancer.

Purpose of the Study:

  • To develop novel activatable protein-transduction domains (APTDs) for targeted delivery to prostate cancer.
  • To engineer molecules for selective cellular uptake mediated by prostate-specific antigen (PSA).
  • To identify effective PSA-cleavable sequences for APTD activation.

Main Methods:

  • Convergent synthesis of d-arginine octamer (r8) based APTDs.
  • Evaluation of APTD stability in serum.
  • Testing PSA-mediated cleavage and subsequent cellular uptake in Jurkat and PC3M cell lines.

Main Results:

  • Identified an effective r8 PTD-attenuating sequence for PSA-mediated cleavage.
  • APTD conjugates demonstrated stability in serum.
  • Selective uptake into Jurkat and PC3M cells was observed only after PSA cleavage.

Conclusions:

  • Developed PSA-cleavable APTDs for targeted delivery to prostate cancer.
  • These peptide-based molecules show potential for enhancing therapeutic and imaging agent delivery to PSA-expressing tumors.
  • APTDs represent a promising strategy for molecularly specific drug delivery in oncology.

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