Expression of small proline rich proteins in neoplastic and inflammatory skin diseases

BACKGROUND: The formation of the cornified cell envelope (CE) during the late stages of epidermal differentiation is essential for epidermal barrier function and protects the body against environmental attack and water loss. Formation of the CE involves the replacement of the plasma membrane by cross-linkage of precursor proteins such as involucrin, small proline rich proteins (SPRR) and loricrin. In normal epidermis, SPRR1 is restricted to appendages, SPRR2 is also expressed in interfollicular areas, while SPRR3 is completely absent; the latter is most abundant in oral epithelium. This differential expression indicates an important part for SPRRs in specific barrier requirements, and reflects their importance in the biomechanical properties of the CE. OBJECTIVES: We report here on the expression of SPRR1, SPRR2 and SPRR3 in a wide range of cutaneous neoplastic and inflammatory diseases. METHODS: We used immunohistochemistry; in addition, Northern blot analysis of malignant tumours was performed. RESULTS: Increased suprabasal expression of SPRR1 and SPRR2, but no SPRR3 expression, was noted in inflammatory dermatoses with orthokeratotic and parakeratotic squamous differentiation. By contrast, differentiating epidermal tumours such as Bowen's disease, keratoacanthoma and squamous cell carcinoma expressed SPRR3. CONCLUSIONS: As SPRRs were originally cloned on the basis of their expression in ultraviolet light-irradiated keratinocytes, the expression of SPRR3 in actinic lesions is of interest, and might serve as a diagnostic tool

Erythème borrélien de la face [Borrelial erythema of the face]

BACKGROUND: Borrelial infection is characterized by various skin manifestations that are usually classified into three main types: chronic migratory erythema, borrelial lymphocytoma and acrodermatitis chronica atrophicans. We report an unusual case of borrelial cutaneous infection presenting as a mediofacial erythema that cannot be included in any of these three categories. CASE REPORT: A 51-year-old woman presented with infiltrated erythema of the middle of the face extending to the neck and chin. Medical history and physical examination revealed no signs of rosaceae. Infection with Borrelia was suspected on skin biopsy examination, which showed an inflammatory dermal infiltrate containing numerous plasma cells. The diagnosis of B.afzelii infection was confirmed by serology and polymerase chain reaction on the skin biopsy, both of which were positive for B.afzelii. DISCUSSION: Borrelial erythema of the face may represent a special form of cutaneous borrelial infection, which must be considered in the differential diagnosis of facial erythema, especially in areas of endemic borreliosis

Molecular characteristics of non-small cell lung cancer

We used hierarchical clustering to examine gene expression profiles generated by serial analysis of gene expression (SAGE) in a total of nine normal lung epithelial cells and non-small cell lung cancers. Separation of normal and tumor, as well as histopathological subtypes, was evident by using the 3,921 most abundant transcript tags. This distinction remained when only 115 highly differentially expressed tags were used. Furthermore, these 115 transcript tags clustered into groups suggestive of the unique biological and pathological features of the different tissues examined. Adenocarcinomas were characterized by high-level expression of small airway-associated or immunologically related proteins, whereas squamous cell carcinomas overexpressed genes involved in cellular detoxification or antioxidation. The messages of two p53-regulated genes, p21(WAF1/CIP1)and 14-3-3σ, were consistently underexpressed in the adenocarcinomas, suggesting that the p53 pathway itself might be compromised in this cancer type. Gene expression patterns observed by SAGE were consistent with results obtained by quantitative real-time PCR or cDNA array analyses by using a total of 43 lung tumor and normal samples. Thus, although derived from only a few tissue libraries, gene expression profiles obtained by using SAGE most likely represent an unbiased yet distinctive molecular signature for the most common forms of human lung cancer