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Updated: Aug 25, 2026

A General Method for Detecting Nitrosamide Formation in the In Vitro Metabolism of Nitrosamines by Cytochrome P450s
Published on: September 25, 2017
Enzyme polymorphisms influencing the metabolism of heterocyclic aromatic amines
Luisa Airoldi1, Cinzia Magagnotti, Roberta Pastorelli
1Department of Environmental Health Sciences, Istituto di Ricerche Farmacologiche Mario Negri, Via Eritrea 62, Milan 20157, Italy. airoldi@marionegri.it
Abstract:
Heterocyclic aromatic amines are dietary carcinogens possibly involved in human carcinogenesis, DNA-adduct formation being an obligatory step in this multistage process. Heterocyclic amine binding to DNA largely depends on the balance between metabolic activation and detoxification pathways and DNA repair efficiency. Several genes coding for metabolic enzymes are polymorphic, which affects gene expression and/or enzyme activity. This paper briefly reviews the effect of polymorphisms of activating/detoxifying enzymes on the metabolism of heterocyclic amines. Despite some epidemiological evidence of an association between genetic polymorphisms and susceptibility to cancer possibly resulting from dietary exposure to heterocyclic aromatic amines (HA), the genetic polymorphisms had only slight effects on biomarker levels, suggesting the existence of further unknown factors.
Insights
Genetic variations in metabolic enzymes influence heterocyclic aromatic amine (HAA) metabolism, a key step in cancer development. However, these genetic polymorphisms show only minor effects on biomarkers, indicating other factors are involved.
Area of Science:
- Biochemistry
- Genetics
- Cancer Research
Background:
- Heterocyclic aromatic amines (HA) are dietary carcinogens linked to human cancer.
- DNA adduct formation is a crucial step in HA-induced carcinogenesis.
- Metabolic activation, detoxification, and DNA repair influence HA binding to DNA.
Purpose of the Study:
- To review the impact of genetic polymorphisms in metabolic enzymes on HA metabolism.
- To explore the relationship between genetic variations and cancer susceptibility from dietary HA exposure.
Main Methods:
- Literature review focusing on polymorphisms of activating/detoxifying enzymes.
- Analysis of epidemiological evidence linking genetic polymorphisms to cancer risk.
- Examination of biomarker levels in relation to genetic variations.
Main Results:
- Polymorphisms in genes for metabolic enzymes affect HA metabolism.
- Epidemiological studies suggest associations between genetic polymorphisms and cancer susceptibility.
- Observed effects of genetic polymorphisms on biomarker levels were slight.
Conclusions:
- Genetic polymorphisms have a limited impact on HA biomarker levels.
- Unknown factors likely play a significant role in HA-induced carcinogenesis.
- Further research is needed to identify additional contributing factors.
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