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Global Level Quantification of Histone Post-Translational Modifications in a 3D Cell Culture Model of Hepatic Tissue
Published on: May 5, 2022
Methyl deficiency, alterations in global histone modifications, and carcinogenesis
Igor P Pogribny1, Volodymyr P Tryndyak, Levan Muskhelishvili
1National Center for Toxicological Research, Jefferson, AR 72079, USA. igor.pogribny@fda.hhs.gov
The Journal of Nutrition
|December 22, 2006
Summary
Methyl-deficient diets induce liver cancer in rodents via epigenetic changes. This study reveals altered histone modifications and enzyme expression during hepatocarcinogenesis, highlighting their role in tumor development.
Area of Science:
- Epigenetics
- Hepatocarcinogenesis
- Molecular Biology
Background:
- Methyl-deficient diets (MDD) induce liver cancer in rodents through chronic metabolic stress.
- Epigenetic alterations are key mechanisms in the malignant transformation of liver cells.
- Understanding these epigenetic changes is crucial for studying carcinogenesis.
Purpose of the Study:
- To investigate global histone modification patterns in the liver during methyl-deficient diet-induced hepatocarcinogenesis.
- To analyze the expression of histone-modifying enzymes in relation to these epigenetic changes.
Main Methods:
- Rodents were fed a methyl-deficient diet to induce hepatocarcinogenesis.
- Global histone modification patterns (trimethylation and acetylation) were analyzed in liver tissue.
- Expression levels of specific histone methyltransferases (HMTs) and histone acetyltransferase 1 (HAT1) were quantified.
Main Results:
- MDD led to progressive loss of H4K20me3 and H3K9ac, and increases in H3K9me3 and H4K16ac in the liver.
- Liver tumors showed decreased H4K20me3 and H3K9ac, but increased H3K9me3 and H4K16ac.
- Expression of Suv4-20h2 and RIZ1 HMTs decreased, while Suv39-h1 HMT and HAT1 expression increased in tumors.
Conclusions:
- Histone modification patterns are significantly altered during MDD-induced hepatocarcinogenesis.
- Changes in histone-modifying enzyme expression correlate with observed epigenetic alterations.
- These findings underscore the critical role of epigenetic modifications in liver cancer development.
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