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Related Experiment Video

Updated: Mar 6, 2026

Isolation and Staining of Mouse Skin Keratinocytes for Cell Cycle Specific Analysis of Cellular Protein Expression by Mass Cytometry

Isolation and Staining of Mouse Skin Keratinocytes for Cell Cycle Specific Analysis of Cellular Protein Expression by Mass Cytometry

Published on: May 9, 2019

Cell-Cycle Regulation Accounts for Variability in Ki-67 Expression Levels.

Michal Sobecki¹, Karim Mrouj¹, Jacques Colinge²

¹IGMM, CNRS Univ. Montpellier, Montpellier, France.

Cancer Research

|March 12, 2017

Summary

This summary is machine-generated.

Cell-cycle regulation explains variable Ki-67 expression in cancer and normal cells. Ki-67 reliably indicates CDK4/CDK6 inhibitor effects on cell proliferation.

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Area of Science:

Cell Biology
Cancer Research
Molecular Biology

Background:

The cell proliferation marker Ki-67 is crucial in cancer histopathology.
Inconsistent Ki-67 expression estimations and limited understanding of its regulation pose challenges.

Purpose of the Study:

To investigate the role of cell-cycle regulation in Ki-67 expression variability.
To determine if Ki-67 remains a reliable proliferation marker under CDK4/CDK6 inhibition.

Main Methods:

Analysis of Ki-67 expression in various cell types and tissues (human and mouse).
Investigated Ki-67 mRNA and protein dynamics throughout the cell cycle.
Utilized CDK4/CDK6 inhibition (in vitro and in vivo) to assess Ki-67 regulation and response.

Main Results:

Cell-cycle regulation was identified as the primary driver of Ki-67 expression variability across all analyzed conditions.
Ki-67 mRNA levels peaked in G2, while protein levels increased through the cell cycle, peaking in mitosis.
CDK4/CDK6 inhibition induced G1 arrest and eliminated Ki-67 mRNA in RB1-positive cells, but not in RB1-negative cells.

Conclusions:

Ki-67 expression is intrinsically linked to cell-cycle progression and regulation.
Despite variability, Ki-67 remains a dependable indicator for evaluating the efficacy of CDK4/CDK6 inhibitors in targeting cell proliferation.