Related Experiment Video

Updated: May 28, 2026

Analysis of Cell Cycle Position in Mammalian Cells
12:19

Analysis of Cell Cycle Position in Mammalian Cells

Published on: January 21, 2012

Subcellular compartmentalization dependent dichotomy of p21 in cancer

Mayank Maheshwari1,2, Munesh K Harioudh3,4

  • 1Marlene & Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, MD, 21201, USA. mmaheshwari1@som.umaryland.edu.

Molecular Biology Reports
|May 27, 2026
PubMed

Insights

The cell cycle regulator p21 (CDK inhibitor) can prevent or promote cancer. Its function depends on its location within the cell, influenced by modifications, impacting cell fate and carcinogenesis.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Cancer Research

Background:

  • p21 (CDK inhibitor) is a key regulator of cell cycle progression and a target of p53.
  • p21's role in oncogenesis is dichotomous, acting as both a tumor suppressor and a promoter.
  • The dual function of p21 is linked to its intracellular localization.

Purpose of the Study:

  • To review the dual role of p21 in oncogenesis.
  • To elaborate on p21's compartment-specific functions.
  • To explore how post-translational modifications regulate p21's function in cancer.

Main Methods:

  • Literature review of p21's function in cell cycle regulation.
  • Analysis of studies on p21's intracellular localization and its impact on cancer.
  • Examination of post-translational modifications affecting p21 localization and activity.

Main Results:

  • Nuclear p21 exhibits anti-cancerogenic activity by arresting the cell cycle.
  • Cytoplasmic p21 promotes tumorigenesis.
  • Post-translational modifications, primarily phosphorylation, dictate p21's localization and subsequent effects.

Conclusions:

  • p21's function in cancer is context-dependent, determined by its subcellular location.
  • Post-translational modifications are critical regulators of p21's dichotomous role in carcinogenesis.
  • Understanding p21's localization and modification provides insights into cancer development and potential therapeutic strategies.
Keywords:
CDK inhibitorNuclear and cytoplasmic p21OncoproteinPost-translational modificationsTumor suppressor

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