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Updated: May 29, 2026
07:33
In vitro Organoid Culture of Primary Mouse Colon Tumors
Published on: May 17, 2013
PTEN regulates colorectal epithelial apoptosis through Cdc42 signalling
R Deevi1, A Fatehullah, I Jagan
1Centre for Cancer Research and Cell Biology, Queen's University of Belfast, Lisburn Road, Belfast BT97BL, UK.
British Journal of Cancer
|September 29, 2011
Summary
Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) influences colorectal cell apoptosis via Cdc42 signaling. PTEN loss reduces Cdc42 activity, inhibiting apoptosis, while PTEN activation enhances it.
Area of Science:
- Cell Biology
- Molecular Biology
- Cancer Research
Background:
- The tumor suppressor PTEN regulates epithelial cell polarity via Cdc42 signaling.
- The precise role of this PTEN-Cdc42 network in regulating apoptosis is not well understood.
Purpose of the Study:
- To elucidate the function of Cdc42 in PTEN-mediated apoptosis in colorectal cells.
- To investigate the molecular mechanisms linking PTEN, Cdc42, and programmed cell death.
Main Methods:
- Utilized isogenic PTEN-expressing and -deficient colorectal cell lines (HCT116, Caco2).
- Employed flow cytometry, in vitro pull-down assays, and immunoblotting for PARP cleavage analysis.
- Manipulated Cdc42 activity and PTEN levels using transfection, siRNA, and pharmacological treatments (NaBt, LiCl).
Main Results:
- PTEN loss or suppression decreased Cdc42 activity, PARP cleavage, and apoptosis.
- Activated Cdc42 enhanced PARP cleavage and apoptosis; Cdc42 silencing inhibited these processes.
- PTEN upregulation by NaBt increased Cdc42 activity, PARP cleavage, and apoptosis.
- Cdc42 signaling suppressed GSK3β activity, and GSK3β inhibition mimicked Cdc42's pro-apoptotic effects.
Conclusions:
- PTEN signaling modulates apoptosis in colorectal epithelium through the Cdc42 pathway.
- This pathway integrates regulation of both cell proliferation and programmed cell death.
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