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Updated: Jul 2, 2026

RhoC GTPase Activation Assay
09:58

RhoC GTPase Activation Assay

Published on: August 22, 2010

Rho/ROCK/actin signaling regulates membrane androgen receptor induced apoptosis in prostate cancer cells

Natalia Papadopoulou1, Ioannis Charalampopoulos, Konstantinos Alevizopoulos

  • 1Department of Biochemistry, University of Crete Medical School, GR-71110 Heraklion, Greece.

Experimental Cell Research
|August 13, 2008
PubMed

Insights

This study reveals a new pathway where Rho GTPases control actin reorganization and apoptosis in prostate cancer cells. This pathway is activated by membrane androgen receptor agonists, impacting both hormone-sensitive and insensitive cancer cells.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Oncology

Background:

  • Prostate cancer cells exhibit varying sensitivity to hormones.
  • Actin reorganization plays a role in cellular processes, including apoptosis.
  • Membrane androgen receptors (mARs) are involved in prostate cancer cell signaling.

Purpose of the Study:

  • To investigate a novel Rho GTPase-dependent pathway.
  • To determine the role of actin reorganization in apoptosis.
  • To explore the effects of mAR agonists on prostate cancer cells.

Main Methods:

  • Utilized hormone-sensitive (LNCaP) and insensitive (DU145) prostate cancer cell lines.
  • Stimulated cells with testosterone-BSA, a membrane-impermeable androgen agonist.
  • Assessed actin polymerization, apoptosis, and Rho GTPase activation (RhoA/B, Cdc42) and downstream effectors (ROCK, LIMK2, ADF/destrin).
  • Employed dominant-negative mutants and pharmacological inhibitors.

Main Results:

  • Testosterone-BSA induced actin polymerization and apoptosis in both cell lines, reversible by actin-disrupting agents.
  • Activated RhoA/B and Cdc42, leading to downstream effector stimulation in DU145 cells.
  • Inhibition of RhoA/B, Cdc42, or ROCK blocked testosterone-BSA-induced actin organization and apoptosis.
  • RhoA/B and ROCK activation were implicated in mAR-dependent processes in LNCaP cells.

Conclusions:

  • Rho small GTPases are key effectors of membrane androgen receptors.
  • These GTPases control actin reorganization and apoptosis in prostate cancer cells.
  • The identified pathway is relevant to both hormone-sensitive and hormone-insensitive prostate cancers.

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