Parameters Related to Oxygen Free Radicals in Human Skin: A Study Comparing Healthy Epidermis and Skin Cancer Tissue

Abstract

In vitro studies with tumor cells have demonstrated that oxygen free radicals are involved in the development of skin cancers and that variations in the body's defense mechanisms can modify the course of the disease. To assess the validity of this hypothesis in spontaneous tumors, we determined glutathione S-transferase, superoxide dismutase, reduced and oxidized glutathione, and thiobarbituric acid reactive substances in healthy whole skin (n = 95), dermis (n = 73), and epidermis (n = 69). The values were compared with those obtained in three types of skin cancer: basal cell carcinoma (n = 16), squamous cell carcinoma (n = 6), and melanoma (n = 33). In healthy skin, glutathione S-transferase, superoxide dismutase, reduced glutathione, and oxidized glutathione were higher in epidermis than in dermis, whereas thiobarbituric acid reactive substances were higher in dermis than in epidermis; whole skin had intermediate values. These results suggest that there is an induction of some anti-oxygen free radicals mechanisms in epidermis as a result of increased oxygen free radicals production. Glutathione S-transferase and thiobarbituric acid reactive substances were higher in all types of tumor than in healthy epidermis but oxidized glutathione was lower. Reduced glutathione and superoxide dismutase activity were lower in basal cell carcinoma and squamous cell carcinoma samples. Glutathione S-transferase increased, whereas superoxide dismutase and thiobarbituric acid reactive substances decreased in melanoma samples in direct relation to the Clark levels. Higher glutathione S-transferase activity, particularly in the most invasive forms of melanoma, indicates that this type of cancer is more malignant. Similarly, a decrease in superoxide dismutase activity can also encourage progression of the tumor. These results are in accord with those from tumor cell cultures and could suggest new strategies (gene therapy) for managing skin cancer.

Successful management of mild atopic dermatitis in adults with probiotics and emollients

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Elevated 8-Isoprostane Levels in Basal Cell Carcinoma and in Uva Irradiated Skin

“…Studies have demonstrated a persistent oxidative microenvironment in cancer tissue including BCC (5,14). Higher levels of reactive biomolecules derived from ROS mediated lipid peroxidation such as TBARS, or DNA derived 8-hydroxi -2-deoxyguanosine (80HdG), were found in BCC lesion compared to healthy controls (6).…”

Reactive Intermediates and the Pathogenesis of Adverse Drug Reactions: The Toxicology Perspective

“…Plasma proteins serve a similar albeit non-specific detoxification capacity. The skin defense system includes the enzymes GST, GPx, SOD, and GRx, CAT, which are higher in the epidermis, and thiobarbituric reactive substances which are prevalent in the dermis [77][78] and NAT1. An imbalance between bioactivation and detoxification processes results in an excess of reactive intermediates that can contribute to the development of drug hypersensitivity syndrome [79][80].…”