Related Experiment Video

Updated: May 31, 2026

Utilization of the Soft Agar Colony Formation Assay to Identify Inhibitors of Tumorigenicity in Breast Cancer Cells
11:06

Utilization of the Soft Agar Colony Formation Assay to Identify Inhibitors of Tumorigenicity in Breast Cancer Cells

Published on: May 20, 2015

The inhibitor of growth protein 5 (ING5) depends on INCA1 as a co-factor for its antiproliferative effects

Feng Zhang1, Nicole Bäumer, Miriam Rode

  • 1Department of Medicine, Hematology/Oncology, University of Münster, Münster, Germany.

Plos One
|July 14, 2011
PubMed

Insights

Inhibitor of Growth 5 (ING5) suppresses cell growth and promotes apoptosis, but only when interacting with Inhibitor of Cyclin A1 (INCA1). ING5 is downregulated in AML, and its function is dependent on INCA1.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Cancer Research

Background:

  • The Inhibitor of Growth (ING) protein family plays crucial roles in cell cycle regulation, apoptosis, and chromatin remodeling.
  • The specific function of ING5 and its interaction partners in growth suppression remain largely uncharacterized.

Purpose of the Study:

  • To elucidate the role of ING5 in cell growth suppression and identify its necessary interaction partners.
  • To investigate the functional dependence of ING5 on INCA1 in cellular processes.

Main Methods:

  • Yeast-two-hybrid screening to identify ING5 interaction partners.
  • Retroviral transduction to assess ING5 function in bone marrow colony formation.
  • Overexpression studies in murine embryonic fibroblast (MEF) cells (Inca1(+/+) and Inca1(-/-)) to evaluate proliferation, cell cycle progression, and apoptosis.

Main Results:

  • ING5 was identified as an interaction partner of INCA1.
  • ING5 expression was significantly reduced in acute myeloid leukemia (AML) blasts compared to normal bone marrow.
  • ING5 inhibited bone marrow colony formation, but this effect was abolished in Inca1(-/-) cells.
  • ING5-mediated suppression of cell proliferation, S-phase delay, and enhancement of Fas-induced apoptosis were dependent on the presence of INCA1.

Conclusions:

  • ING5 functions as a growth suppressor, with its activity contingent upon interaction with INCA1.
  • The suppressed expression of ING5 in AML suggests a potential role in leukemogenesis.
  • INCA1 is essential for mediating the growth-suppressive and apoptosis-inducing functions of ING5.

Related Concept Videos

Inhibition of Cdk Activity02:34

Inhibition of Cdk Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
Inhibition of CDK Activity02:34

Inhibition of CDK Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
Negative Regulator Molecules01:23

Negative Regulator Molecules

Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
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 daughter...
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 daughter...
Inhibitors of Bacterial Protein Synthesis01:25

Inhibitors of Bacterial Protein Synthesis

Aminoglycosides constitute a highly potent class of bactericidal antibiotics that exert their antimicrobial effects by targeting the bacterial ribosome, specifically disrupting protein synthesis. These polycationic molecules consist of amino-modified sugars linked via glycosidic bonds to an aminocyclitol core such as 2-deoxystreptamine or streptamine. Their strong positive charges facilitate tight binding to the negatively charged phosphate backbone of ribosomal RNA (rRNA), primarily at the 16S...