Related Experiment Video

Updated: Apr 30, 2026

Detection of Aggregation-Prone Behavior in Mutant P53 V157F Breast Cancer Cells Using Multipoint Thioflavin T Fluorescence
04:56

Detection of Aggregation-Prone Behavior in Mutant P53 V157F Breast Cancer Cells Using Multipoint Thioflavin T Fluorescence

Published on: December 30, 2025

371

Cancer-associated PTEN mutants act in a dominant-negative manner to suppress PTEN protein function

Antonella Papa1, Lixin Wan2, Massimo Bonora3

  • 1Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.

Cell
|April 29, 2014
PubMed

Insights

PTEN protein forms dimers to regulate its activity. Cancer-associated PTEN mutations can impair this function, leading to increased tumor susceptibility and effects similar to complete PTEN loss.

Area of Science:

  • Molecular Biology
  • Oncology
  • Biochemistry

Background:

  • PTEN (Phosphatase and tensin homolog) is a critical tumor suppressor.
  • PTEN dysfunction is implicated in various cancers.
  • Understanding PTEN regulation is vital for cancer therapy.

Purpose of the Study:

  • To investigate the role of PTEN homodimerization and heterodimerization with mutant forms in regulating PTEN activity.
  • To elucidate the in vivo consequences of cancer-associated PTEN mutations.
  • To differentiate the effects of PTEN loss from PTEN mutations in cancer pathogenesis.

Main Methods:

  • Biochemical assays to study PTEN homodimerization and lipid phosphatase activity.
  • Generation and analysis of Pten knockin mouse models with specific cancer-associated mutations (PtenC124S, PtenG129E).
  • Assessment of PI3-K/Akt pathway activation in cells and tissues from Pten knockin mice.

Main Results:

  • PTEN homodimerizes in an active conformation, dephosphorylating phosphatidylinositol (3,4,5)-trisphosphate (PtdIns(3,4,5)P3).
  • Catalytically inactive PTEN mutants heterodimerize with wild-type PTEN, inhibiting its activity in a dominant-negative manner.
  • Pten knockin mice with heterozygous mutations showed increased PI3-K/Akt activation sensitivity and heightened tumor predisposition, mimicking complete Pten loss.

Conclusions:

  • PTEN mutations and complete PTEN loss are distinct mechanisms in cancer development.
  • PTEN dimerization is a key regulatory mechanism for its tumor-suppressive function.
  • Cancer-associated PTEN mutations can act dominantly, impacting wild-type PTEN activity and promoting tumorigenesis.

More Related Videos

The Soft Agar Colony Formation Assay08:01

The Soft Agar Colony Formation Assay

Published on: October 27, 2014

112.5K
Inducible and Reversible Dominant-negative DN Protein Inhibition08:35

Inducible and Reversible Dominant-negative DN Protein Inhibition

Published on: January 7, 2019

7.7K

Related Concept Videos

Abnormal Proliferation02:23

Abnormal Proliferation

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the...
4.0K
Cancer-Critical Genes II: Tumor Suppressor Genes01:05

Cancer-Critical Genes II: Tumor Suppressor Genes

Genes usually encode proteins necessary for the proper functioning of a healthy cell. Mutations can often cause changes to the gene expression pattern, thereby altering the phenotype.
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
8.3K
Cancer-Critical Genes II: Tumor Suppressor Genes01:05

Cancer-Critical Genes II: Tumor Suppressor Genes

2.6K
Loss of Tumor Suppressor Gene Functions01:12

Loss of Tumor Suppressor Gene Functions

Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable damage. Hence, they play an essential role in preventing the proliferation of damaged cells.
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
4.9K
Loss of Tumor Suppressor Gene Functions01:12

Loss of Tumor Suppressor Gene Functions

1.7K
Cancer-Critical Genes I: Proto-oncogenes01:33

Cancer-Critical Genes I: Proto-oncogenes

Genes usually encode proteins necessary for the proper functioning of a healthy cell. Mutations can often cause changes to the gene expression pattern, thereby altering the phenotype.
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
9.1K