Divergence between the high rate of p53 mutations in skin carcinomas and the low prevalence of anti-p53 antibodies.

Circulating anti-p53 antibodies have been described and used as tumoural markers in patients with various cancers and strongly correlate with the p53 mutated status of the tumours. No study has yet looked at the prevalence of such antibodies in skin carcinoma patients although these tumours have been shown to be frequently p53 mutated. Most skin carcinoma can be diagnosed by examination or biopsy, but aggressive, recurrent and/or non-surgical cases' follow up would be helped by a biological marker of residual disease.

Analyses of cutaneous fluoroquinolones photoreactivity using the integrated model for the differentiation of skin reactions.

Currently available test models for the differentiation of photoallergic and photoirritant reactions are extremely time consuming and the protocols are very heterogeneous. In vitro tests are of proven value in predicting irritant or toxic effects, but these tests fail to predict chemical-induced allergic side effects. We developed test systems for this endpoint which is not easily detected by existing assays.

Effects of ultraviolet A and antioxidant defense in cultured fibroblasts and keratinocytes.

Lipid peroxidation, measured by the thiobarbituric acid-reactive substances assay, was evaluated for cultured human skin fibroblasts and keratinocytes exposed to ultraviolet A radiation (320-400 nm, UVA). Peroxidation increases with increasing UVA doses and is much lower for keratinocytes than for fibroblasts. Immediate UVA-induced cytotoxicity, monitored by the trypan blue exclusion assay, is also lower for keratinocytes.

UVA-induced immune suppression in human skin: protective effect of vitamin E in human epidermal cells in vitro.

UVA (320-400 nm) radiation damage to membranes, proteins, DNA and other cellular targets is predominantly related to oxidative processes. In the present study, we demonstrated that cutaneous UVA-induced immunosuppression can be related, at least in part, to the appearance of these oxidative processes. The UVA-induced oxidative processes in freshly isolated epidermal cells were monitored by measuring the thiobarbituric acid reactive substances (TBARS) as an index of peroxidation.

Action spectrum for UV-induced lipid peroxidation in cultured human skin fibroblasts.

Lipid peroxidation was measured by release of thiobarbituric acid-reactive substances (TBARS) into the supernatant of cultured human skin fibroblasts. This process is triggered by ultraviolet A (UVA) and ultraviolet B (UVB) radiations. For UVA irradiances and irradiation times up to 40 W.