Cytochrome P450 1A2 (CYP1A2) activity, mammographic density, and oxidative stress: a cross-sectional study

INTRODUCTION: Mammographically dense breast tissue is a strong predictor of breast cancer risk, and is influenced by both mitogens and mutagens. One enzyme that is able to affect both the mitogenic and mutagenic characteristics of estrogens is cytochrome P450 1A2 (CYP1A2), which is principally responsible for the metabolism of 17β-estradiol. METHODS: In a cross-sectional study of 146 premenopausal and 149 postmenopausal women, we examined the relationships between CYP1A2 activity, malondialdehyde (MDA) levels, and mammographic density. In vivo CYP1A2 activity was assessed by measuring caffeine metabolites in urine. Levels of serum and urinary MDA, and MDA–deoxyguanosine adducts in DNA were measured. Mammograms were digitized and measured using a computer-assisted method. RESULTS: CYP1A2 activity in postmenopausal women, but not in premenopausal women, was positively associated with mammographic density, suggesting that increased CYP1A2 activity after the menopause is a risk factor for breast cancer. In premenopausal women, but not in postmenopausal women, CYP1A2 activity was positively associated with serum and urinary MDA levels; there was also some evidence that CYP1A2 activity was more positively associated with percentage breast density when MDA levels were high, and more negatively associated with percentage breast density when MDA levels were low. CONCLUSION: These findings provide further evidence that variation in the activity level of enzymes involved in estrogen metabolism is related to levels of mammographic density and potentially to breast cancer risk

Connective tissue diseases in adolescents

In this article we provide a brief review of systemic lupus erythematosus, juvenile dermatomyositis, systemic scleroderma, and mixed connective tissue disease in adolescents. As skin manifestations often belong to the presenting symptoms and may have a significant impact on the quality of life, dermatologists play an important role in the management of patients with connective tissue diseases. Early diagnosis and therapy onset are crucial for the patients' long-term outcome

Parallels between wound healing, chronic inflammatory skin diseases and neoplasia. Clinical aspects

Chronic wounds, scars, burns and recalcitrant chronic inflammatory skin lesions can give rise to malignancy. These neoplasias are usually squamous cell carcinomas but basal cell carcinomas can also develop. Tumorigenesis is a severe complication of chronic ulcers as well as certain inflammatory skin diseases; early diagnosis is critical for prognosis. This article describes parallels between wound healing, chronic inflammatory skin diseases and carcinogenesis and provides advice on practical aspects of diagnosis and therapy

Challenges in neonatal dermatology An introduction

In order to support dermatologists' interest for the fascinating area of neonatal dermatology, we provide (1) an introduction to the specifics of skin barrier in premature and full-term neonates as well as their clinical implications and (2) an example of age-dependent differential diagnoses and approach to a facial vascular stain in a neonate