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Updated: May 21, 2026
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Assessing Cellular Target Engagement by SHP2 (PTPN11) Phosphatase Inhibitors
Published on: July 17, 2020
SHP-2 and PTP-pest induction during Rb-E2F associated apoptosis
Liza D Morales1, Karina Pena, Dae Joon Kim
1Department of Biology, The University of Texas-Pan American, Edinburg, TX, USA.
Cellular & Molecular Biology Letters
|May 31, 2012
Summary
The Retinoblastoma (Rb)-E2F pathway regulates cell cycle and apoptosis for tumor suppression. This study identifies SHP-2 and PTP-PEST as key protein tyrosine phosphatases (PTPs) in p53-independent apoptosis.
Area of Science:
- Molecular Biology
- Cell Biology
- Cancer Research
Background:
- Apoptosis is crucial for tumor suppression, linked to cell cycle regulation via the Retinoblastoma (Rb)-E2F pathway.
- Loss of Rb activity can trigger apoptosis through p53-dependent and independent pathways.
- Protein tyrosine phosphatases (PTPs) are increasingly recognized for their role in Rb-E2F-associated apoptosis.
Purpose of the Study:
- To investigate the role of additional PTPs in p53-independent apoptosis.
- To identify PTPs directly activated by the Rb-E2F pathway.
Main Methods:
- Analysis of Rb-E2F pathway activation.
- Assays to determine PTP activation and function.
- Investigation of apoptotic signaling pathways.
Main Results:
- The Rb-E2F pathway directly activates SHP-2 and PTP-PEST.
- These PTPs contribute to p53-independent apoptotic signaling.
- PTP-1B's role in inactivating focal adhesion kinase during p53-independent apoptosis is further contextualized.
Conclusions:
- SHP-2 and PTP-PEST are novel contributors to p53-independent apoptosis initiated by Rb-E2F pathway dysregulation.
- These findings expand the understanding of molecular mechanisms underlying tumor suppression and apoptosis.
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