Related Experiment Video
Updated: Mar 7, 2026
10:38
Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters
Published on: September 27, 2012
23.3K
Critical cholangiocarcinogenesis control by cryptochrome clock genes
Ali Mteyrek1, Elisabeth Filipski1, Catherine Guettier2
1INSERM and Paris Sud university, UMRS 935, Team "Cancer Chronotherapy and Postoperative Liver", Campus CNRS, Villejuif, F-94807, France.
International Journal of Cancer
|February 23, 2017
Summary
Disrupting the Cry1 and Cry2 molecular clock genes in mice significantly increased chemically induced liver cancer, particularly bile duct cholangiocarcinomas. This highlights the critical role of circadian rhythms in preventing liver carcinogenesis.
Area of Science:
- Chronobiology
- Hepatology
- Carcinogenesis
Background:
- Molecular circadian clocks regulate liver metabolism and proliferation.
- Circadian disruption accelerates liver cancer development.
- The roles of Cryptochrome (Cry) clock genes in liver carcinogenesis are unclear.
Purpose of the Study:
- To investigate the role of Cry1 and Cry2 in diethylnitrosamine (DEN)-induced liver carcinogenesis.
- To determine if the absence of Cry1 and Cry2 influences the development of specific liver cancer types.
Main Methods:
- Male wild-type (WT) and Cry1-/- Cry2-/- mice were exposed to DEN.
- Rest-activity and body temperature rhythms were monitored.
- Liver function enzymes (AST, ALT, ALP) and tumor development (hepatocarcinoma, cholangiocarcinoma) were assessed.
Main Results:
- Cry1-/- Cry2-/- mice exhibited severe liver dysplasia and elevated liver enzymes.
- DEN exposure led to a fivefold increase in primary liver cancers in Cry1-/- Cry2-/- mice.
- A significant eightfold increase in cholangiocarcinomas was observed in Cry1-/- Cry2-/- mice compared to WT mice.
Conclusions:
- Molecular circadian clock disruption dramatically increases chemically induced liver carcinogenesis.
- Cry clock genes play a critical role in preventing bile duct carcinogenesis, with their absence promoting cholangiocarcinoma development.
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