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Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols
12:02

Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols

Published on: June 6, 2017

p18 Ink4c and Pten constrain a positive regulatory loop between cell growth and cell cycle control

Feng Bai1, Xin-Hai Pei, Pier Paolo Pandolfi

  • 1Lineberger Comprehensive Cancer Center, Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7295, USA.

Molecular and Cellular Biology
|June 2, 2006
PubMed

Insights

Mutations in cell cycle control and cell growth pathways accelerate tumor development. The p18 Ink4c and Pten genes cooperate in tumor suppression, impacting prostate cancer progression.

Area of Science:

  • Oncology
  • Molecular Biology
  • Genetics

Background:

  • The Retinoblastoma (Rb)-mediated G1 cell cycle control pathway is frequently inactivated in human cancers.
  • Understanding interactions between tumor suppressors is crucial for developing effective cancer therapies.

Purpose of the Study:

  • To investigate the interplay between the cyclin-dependent kinase (CDK) inhibitor p18 Ink4c and the lipid phosphatase Pten in tumor suppression.
  • To characterize the spectrum and progression of tumors in mice with combined p18 Ink4c and Pten mutations.

Main Methods:

  • Generation and characterization of mice with combined p18 Ink4c and Pten gene mutations.
  • Analysis of tumor development, including prostate cancer, in genetically modified mice.
  • Assessment of Pten allele loss and its correlation with tumor suppressor activity.

Main Results:

  • Double mutant mice exhibited a broader range of tumors, notably prostate cancer, with high penetrance and accelerated onset.
  • Pten haploinsufficiency in tumor suppression was found to be tissue- and genetic background-dependent.
  • Activation of Akt/Protein Kinase B (PKB) was observed upon p18 deletion, CDK4 overexpression, or Rb inactivation, and was recessive to reduced PTEN activity.

Conclusions:

  • The p18 Ink4c and Pten pathways cooperate in suppressing tumors by regulating the balance between cell growth and cell cycle control.
  • These findings highlight the complex genetic interactions underlying tumor initiation and progression.

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