CYP2A13

CYP2A13 is a member of the cytochrome P450 superfamily of enzymes. These enzymes are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids, and other lipids. The CYP2A13 gene is located on chromosome 19q13.2 and is primarily expressed in the respiratory tract.

Function

CYP2A13 is known for its role in the metabolic activation of several procarcinogens, including tobacco-specific nitrosamines such as NNK (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone). This enzyme is highly efficient in converting these compounds into their active carcinogenic forms, which can then bind to DNA and potentially lead to mutations and cancer.

Expression

The expression of CYP2A13 is predominantly found in the nasal mucosa, but it is also present in other tissues of the respiratory tract, including the trachea and lung. This localized expression suggests that CYP2A13 plays a significant role in the first-pass metabolism of inhaled substances.

Genetic Variability

There is considerable genetic variability in the CYP2A13 gene among different populations. Certain polymorphisms in the CYP2A13 gene can lead to altered enzyme activity, which may influence an individual's susceptibility to the harmful effects of tobacco smoke and other inhaled carcinogens.

Clinical Significance

Due to its role in activating tobacco-specific nitrosamines, CYP2A13 is of particular interest in the study of lung cancer and other respiratory diseases. Understanding the variations in CYP2A13 activity among individuals can help in assessing the risk of developing these conditions and in developing personalized medical approaches.

See Also

• Cytochrome P450
• Drug metabolism
• Lung cancer
• Tobacco-specific nitrosamines
• Genetic polymorphism