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Notes: Abstract: The role of urokinase type plasminogen activator (uPA) has been well documented in the pathogenesis of pemphigus vulgaris (PV). Activation of plasminogen into active serine protease plasmin initiates extracellular proteolysis leading to acantholysis but the mechanisms underlying this process are not clearly understood. We have previously shown that keratinocyte derived cytokines IL-1α and TNF-α are involved in PV-induced acantholysis. In the present study we sought to examine whether keratinocyte-derived IL-1α and TNF-α are correlated with uPA induction in keratinocytes during acantholysis. Normal human keratinocytes were incubated with diluted PV serum. mRNAs for IL-1α, TNF-α and uPA were examined with RT-PCR at various time points and acantholysis was measured. IL-1α, TNF-α and uPA mRNAs were all induced in keratinocytes following PV serum stimulation; IL-1α/TNF-α mRNAs' expression was earlier than the expression of uPA mRNA. To further examine the role of IL-1α, TNF-α and uPA in acantholysis, we performed antibody blocking studies. Anti-IL-1α, anti-TNF-α and anti-uPA antibodies suppressed acantholysis by 76%, 80% and 90%, respectively. In addition, anti-IL-1α and anti-TNF-α antibodies inhibited uPA mRNA induction, whereas anti-uPA antibodies did not alter IL-1α/TNF-α mRNAs' expression. Our results confirm the role of uPA in acantholysis and suggest an involvement of IL-1α/TNF-α in uPA induction.

Notes: Abstract:  The angiogenic mediator vascular endothelial growth factor (VEGF) and its receptors (VEGFRs) have been studied extensively in neoplastic disease and some inflammatory conditions. Contact hypersensitivity (CHS) is a prototypic Langerhans' cell-dependent, T-helper (Th) 1 cell-mediated inflammatory skin disease that is now also thought to involve angiogenic mediators. The purpose of our study was to examine the role of angiogenesis and VEGF in CHS. We demonstrated that VEGF production is up-regulated in murine skin after challenge with dinitrofluorobenzene. Administration of a monoclonal antibody directed against the VEGFR-2 (DC101) resulted in a 28.8% decrease in CHS response (P 〈 0.001). Examination of the DC101-treated mouse skin 24 h after challenge revealed decreases in dermal inflammatory cellular infiltrates and total vessel area. Furthermore, mRNA and protein of the Th1-type cytokine interferon (IFN)-γ was significantly down-regulated in skin of DC101-treated animals 24 h after challenge. The results of the study demonstrate that VEGFR-2 blockade significantly reduces vascular enlargement and edema formation and effects IFN-γ expression in the skin during challenge in CHS. Our findings suggest that DC101 could function by reducing inflammatory cell migration and hence IFN-γ expression during the CHS response.

Notes: Abstract Keratinocyte growth factor (KGF) and its receptor (KGFR) are thought to play important roles in normal keratinocyte growth and differentiation. Since UVB radiation is known to influence keratinocyte growth, we sought to determine whether UVB would alter the expression of KGF and KGFR. Using a reverse-transcription coupled polymerase chain reaction (RT-PCR). the present study examined the expression of KGF and KGFR mRNA in cultured normal human keratinocytes exposed to UVB irradiation. Total cellular RNA was extracted from cultured keratinocytes at various time points after irradiation, reverse transcribed and used for PCR amplification using primers specific for KGF and KGFR. Constitutive expression of KGFR mRNA, but not KGF mRNA, was detected in normal cultured human keratinocytes. After UVB irradiation at 300 J/m2, the KGF mRNA remained undelectable while the KGFR mRNA level was significantly decreased. The downregulation of KGFR mRNA expression was also confirmed by Northern blot analysis. Immunohistochemical studies demonstrated a decreased positive signal of KGFR in human keratinocytes after UVB irradiation. Our results suggest a possible role for the KGF-KGFR signalling pathway in the skin after exposure to UVB, and that UVB-induced growth inhibition of keratinocytes in hyperproliferative skin disorders may be related to downregulation of KGFR.

Notes: The treatment of hand dermatitis is often limited by patients' continued exposure to triggering factors.1 The use of a corticosteroid in a polyacrylic film-forming vehicle, which forms a relatively impermeable film when applied to the skin, may offer an advantage over traditional steroid lotions by affording protection against irritants while allowing patients to perform routine activities using bare hands. Fifty-eight (58) men and women ages 18–70 years participated in a 7-day, double-blind, randomized, positive controlled study to compare the effectiveness of these two vehicles in the treatment of eczematous hand dermatitis.Each patient provided written, informed consent before entering the study, which had been approved by the Institution Review Board at the Sunnybrook Health Science Centre, University of Toronto. All patients had a diagnosis of corticosteroid-responsive dermatitis limited to the hands but were otherwise in good health. Patients were excluded if they had medically significant cutaneous conditions other than eczema of the hands, clinically infected hand dermatitis, or known sensitivity to betamethasone dipropionate or to any vehicle constituents of the products being studied. Therapies that might influence the results were restricted throughout the study and were withdrawn before entering the study as follows: topical corticosteroids, 14 days; systemic corticosteroids, 12 weeks; other topical treatments, 7 days; systemic antimicrobials, all other investigational drugs, radiation therapy (e.g., artificial ultraviolet and tanning devices), 30 days; systemic or topical antihistamlnes, 14 days; and topical anesthetics and topical or systemic analgesics, 48 hours.Patients were randomly assigned to two groups with one group receiving a film-forming lotion (FFL) (betametha-sone dipropionate, 0.05% in a polyacrylic vehicle containing acrylates copolymer, butyl acetate, dibutyl phthalate, isopropyl alcohol, and polyvinyl butyryl). The other group applied a traditional lotion (TL) (betamethasone dipropionate. 0.05% in isopropyl alcohol and purified water slightly thickened with carbomer 934 to resemble the consistency of the other product).2 Bottles were dispensed in their marketed containers with identically appearing overlabels and the contents were not known to the patients or the investigator who assessed the results. Only the study coordinator was aware of the contents of the bottles.Patients applied a thin layer of the assigned medication with a brush to all affected areas of the hands identified by the study investigator every morning and evening, approximately 10–12 hours apart. Covering the hands with bandages, dressings, or gloves was not allowed, but usual handwashing was permitted. Patients returned for reevaluation on days 2, 4, and 7 of the study.At each visit the investigator evaluated the severity of hand dermatitis by grading the degree of pruritus, scaling, erythema, induration, and overall severity according to the following scale: 0 = absent, 1 = mild, 2 = moderate, and 3 = severe. Pretherapy readings were obtained on day 1 with subsequent readings on days 2, 4, and 7. A physician's global evaluation (PGE) for eczema relief was also performed at each visit in which change from baseline was scored as follows: +3 = cleared, +2 = much improved, +1 = improved, 0 = same, −1 = worse, −2 = much worse. The numerical ratings were averaged for both hands. Cochran-Mantel-Haenszel (CMH) methodology with ridit3 assigned scores was used to compare averaged ratings at baseline for the severity of eczema, changes from baseline in eczema severity, and PGE at each subsequent visit.

Notes: Background  Sarcoidosis is a chronic granulomatous disease of unknown etiology. Cutaneous disease is common and includes two clinicopathologic categories: granulomatous infiltration or a reactive phenomenon. In the granulomatous infiltrative group, clinical manifestations can be variable. Ulcers in sarcoidosis are uncommonly recognized and have been categorized previously under the rubric of atrophic, necrobiosis-like, or ulcerative sarcoidosis.Patients and methods  We evaluated retrospectively sarcoidosis patients presenting to the Johns Hopkins Department of Dermatology between June 1989 and May 2002. Multiple skin biopsies were performed for histopathologic evaluation. Investigation for extracutaneous manifestations, including routine serologic assays, chest radiography, pulmonary function tests, electrocardiogram, and angiotensin-converting enzyme level, and referral for ophthalmologic examination were performed in all patients.Results  Of 147 consecutive patients presenting with cutaneous sarcoidosis, seven demonstrated ulcerative-atrophic sarcoidosis lesions. All patients were African-American (five females and two males). All patients had ulcers surrounded by atrophic necrobiosis lipoidica-like plaques on the pretibial areas. All patients had other mucocutaneous manifestations of sarcoidosis, with the majority having evidence of internal disease. Combined immunosuppressive and immunomodulatory therapy was effective in controlling the cutaneous manifestations of all patients with ulcerative sarcoidosis.Conclusions  The ulcerative variant is a poorly defined subset of cutaneous sarcoidosis. Trauma, superimposed on atrophic plaques, appears to be the principal mechanism of this rare variant of cutaneous sarcoidosis.

Notes: Abstract:  Basal cell carcinoma (BCC) is the most common cutaneous malignancy that, like other tumours, possesses a heterogeneous genetic composition. In order to select genes with consistent changes in expression among these tumours, we analysed BCC microarray expression data by using a novel approach, termed correlative analysis of microarrays (CAM). CAM is a nested, non-parametric method designed to qualitatively select candidates based on their individual, similar effects upon an array-wide closeness measure. We applied the CAM method to expression data generated by two-channel cDNA microarray experiments, where 21 BCC and patient-matched normal skin specimens were examined. Fifteen candidate genes were selected, with six overexpressed and nine underexpressed in BCC vs. normal skin. Five of the nine consistently downregulated genes in the tumour samples are involved in mitochondrial function and the oxidative phosphorylation (OXPHOS) pathway. One of these genes was the 7.5-kDa subunit, NADH dehydrogenase (ubiquinone) alpha subcomplex-1 (NDUFA1), an accessory component of OXPHOS complex-I that is essential for respiratory activity. These findings support the hypothesis that irregularities in mitochondrial function are involved in neoplasia. Suppression of NDUFA1 expression could represent a key pathogenic mechanism in the development of BCC.

Notes: Abstract Conflicting reports exist concerning ultraviolet-B (UVB) effects on keralinocyte (KC) interleukin-l (IL-1) expression. To clarify the modulatery effects of UVB on IL-1, the following study was undertaken. Normal human epidermal KCs cultured in a standard low Ca2+ and serum-free medium were irradiated in quiescent phase with UVB. In this study, we used semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) to determine the mRNA level of interleukin-1α (IL-1α) and interleukin-1β (IL-β). After exposure to 100 or 300 J/m2 UVB, a transient increase in mRNA levels was observed within I hour for IL-1α and 3 to 6 h for IL-β Following this transient induction, mRNA levels for both IL-1α and IL-1β returned to steady-state levels after 100 J/m2. After 300 J/m2 irradiation, IL-1α and IL-1β levels were downregulated compared to unirradiated cultures at 24-h post-irradiation. The half-life for IL-1α and IL-1β was estimated using actinomycin D treatment. Both IL-1α and IL-1β mRNAs half-lives (t1/2) decreased faster in irradiated cells (t1/2 = 30 minutes for IL-1α and 2 h for IL-1β) compared to unirradiated cells (t1/2= 1 h and 4 h, respectively). These results suggest that IL-1α and IL-1β mRNA expression are differentially regulated by UVB. In contrast to down-regulation of mRNA levels, a significant increase in IL-1α protein levels, measured by ELISA. was observed in culture supernatant from 6 h to 24 h after 300 J/m2 UVB irradiation. Cycloheximide treatment did not abrogate this increase in IL-1α protein level. Since this dose of UVB irradiation decreased the stability of IL-1α and IL-1β mRNA, this suggests that the release of IL-1α after UVB irradiation was due to leakage from UVB-damaged cells and not from de novo protein synthesis.