Hedgehog- and mTOR-targeted therapies for advanced basal cell carcinomas.

Basal cell carcinomas (BCCs) are the most frequent human cancer. Over 90% of all BCCs have a mutation in PTCH1 or smoothened, two conducting proteins of the Hedgehog pathway. They rarely progress deeply and metastasize; however, if they do, these advanced basal cell carcinoma become amenable to treatment by inhibiting the Hedgehog and the P13K-mTOR pathways. Such innovative drugs include vismodegib, cyclopamine, itraconazole, everolimus and a few other agents that are in early clinical development.

Cyanoacrylate skin surface stripping and the 3S-Biokit advent in tropical dermatology: a look from Liège.

In the dermatopathology field, some simple available laboratory tests require minimum equipment for establishing a diagnosis. Among them, the cyanoacrylate skin surface stripping (CSSS), formerly named skin surface biopsy or follicular biopsy, represents a convenient low cost procedure. It is a minimally invasive method collecting a continuous sheet of stratum corneum and horny follicular casts. In the vast majority of cases, it is painless and is unassociated with adverse events. CSSS can be performed in subjects of any age. The method has a number of applications in diagnostic dermatopathology and cosmetology, as well as in experimental dermatology settings. A series of derived analytic procedures include xerosis grading, comedometry, corneofungimetry, corneodynamics of stratum corneum renewal, corneomelametry, corneosurfametry, and corneoxenometry.

Effect of N-acetylcysteine combined with infliximab on toxic epidermal necrolysis. A proof-of-concept study.

INTRODUCTION: The pathophysiology of toxic epidermal necrolysis (TEN) is thought to be related to a drug-induced oxidative stress combined with TNFα overexpression by keratinocytes. None of the current treatments for TEN including systemic corticosteroids, cyclosporine and intravenous administration of immunoglobulins has proven superior over supportive care only. METHODS: A total of 10 TEN patients were enrolled to be treated at admission in burn units with the antioxidant N-acetylcysteine [NAC, 150mg/kg in a 20-h intravenous (IV) administration], or the combination of the same IV NAC perfusion with the anti-TNFα antibody infliximab (Remicade(®)), administered at a 5mg/kg dosage as a single 2-h IV administration. TEN was confirmed by a skin biopsy taken from a bullous lesion. At entry in the trial and 48h later, the illness auxiliary score (IAS) of clinical severity was determined and the extent in altered skin area (erythema and blisters) was assessed as a relative body area. Skin biopsies of both clinically uninvolved and erythematous areas were collected and immunohistochemistry was performed for assessing the density of inflammatory cells (CD8+ T cells, CD68+ macrophages) and keratinocytes enriched in intracellular calcium (Ca(++)) identified by the Mac387 anti-calprotectin antibody. RESULTS: No unexpected drug-induced adverse event was noticed. After 48h of both treatment modalities, improvements were not observed in the extent of skin involvement and in IAS. Immunohistopathology showed the absence of reduction in the amount of intraepidermal inflammatory cells. An increased intracellular Ca(++) load in clinically uninvolved keratinocytes and in erythematous epidermis was noticed. This latter finding suggested the progression in the way of the apoptotic process. On burn unit discharge, the survival in each modality of treatment was not improved compared to the expected outcomes determined from the IAS at admission. CONCLUSIONS: In this proof-to-concept attempt, NAC treatment or its combination with infliximab did not appear to reverse the evolving TEN process.

Skin viscoelasticity in incipient gravitational syndrome.

BACKGROUND: The gravitational syndrome resulting from venous pressure elevation occasionally develops on the legs during pregnancy. The limb tends to enlarge and become stiffer. The body contours are altered. AIMS: To assess incipient gravitational edema due to chronic venous insufficiency using measurements of the skin tensile strength. METHOD: A total of 21 women aged 28-37 years were enrolled in the study. Evaluations were made twice in each subject following an alternate use and avoidance of daytime elastic contention. Skin viscoelasticity was measured on the mid portion of the calves using a computerized suction device. RESULTS: The discretely increased consistency of skin showing abnormal rheological characteristics at the site of incipient gravitational edema was significantly improved by contention therapy. Under progressive suction measurements, both skin distensibility, biologic elasticity and hysteresis were increased after wearing tight stockings. The biologic elasticity appears to be the most sensitive parameter pointing to the diagnosis of gravitational syndrome. CONCLUSION: Noninvasive measurements of the skin viscoelasticity, particularly the biologic elasticity, represent an objective assessment of both early gravitational edema and its control by contention therapy.

Deciphering supportive treatment strategies for toxic epidermal necrolysis.

Toxic epidermal necrolysis (TEN) is a dreadful life-threatening syndrome typically induced by an adverse drug reaction. This condition is characterized by the sudden and extensive destruction of the epidermis. The patient should be promptly addressed to a burn unit where three types of treatment should be administered, namely, (a) specific topical care of the bullous/eroded skin areas, (b) systemic anti-apoptotic/necrotic treatments, and (c) supportive care preventing secondary internal organ failures. This latter aspect is covered by the present review and focuses on (a) early withdrawal of the causative drug, (b) airway management, (c) hydro-electrolytic control, (d) nutritional support, (e) antibiotherapy, (f) prevention of venous thrombosis and gastroduodenal ulcers, and (g) analgesia and anesthesia.

Proteomic kinetic analysis of blister fluid and serum in a patient with drug-induced toxic epidermal necrolysis. A comparison with skin immunohistochemistry.

Drug-induced toxic epidermal necrolysis (TEN) is a rare but potentially lethal bullous disease whose complex pathomechanisms remain uncertain. The aim of the study was an exploratory attempt to assess TEN pathobiology using a combination of immunohistochemistry and proteomics. Skin blister fluid (BF) and serum were collected in a patient in the early TEN stage at day (D) +4 of evolution and three days later (D +7). Intravenous cyclosporine A (CsA) treatment was initiated since D +4. Immunohistochemistry was performed on skin blister biopsies. In addition, proteomic analyses compared the BF protein content before and at the issue of the 3-day CsA treatment. Proteins were selected according to their prominent differential abundance in BF between D+4 and D+7, when influenced by lesional skin cells, but not in serum. Among 300 proteins, four were considered. Glutathione transferase π was related to oxidative stress in TEN epidermis. The monocyte differentiation antigen CD14 and myeloperoxidase indicated macrophage activation. The proinflammatory S100-A8 protein probably originated from activated keratinocytes and/or macrophages. These proteomic findings were in line with immunohistochemistry and supported the prominent involvement of keratinocytes and macrophages in TEN pathomechanism. As opposed to CD14, other proteins were mainly present in BF at D+7, confirming that CsA expressed little effect, if any, on the activity of keratinocytes and macrophages in the present TEN patient. Of note, the present exploratory study using proteomic analyses in a single TEN case supports a pathogenic hypothesis without establishing any firm conclusion.

Drug interactions with normal and TEN epidermal keratinocytes.

Human epidermal keratinocytes (EKs) are metabolically involved in various drug transport mechanisms, as well as in detoxification or activation processes. The overall cell mechanisms of drug metabolization, and more specifically drug processing are reviewed in normal EKs. The overall drug metabolism involves different phases corresponding to the uptake, biotransformation and anti-transport steps. In EKs, both the enzymes and transportassociated proteins are different from those involved in the hepatocyte metabolism. Some cytochrome P450 enzymes and the flavin-containing mono-oxygenases are particularly involved in EKs. Basically, EKs represent key cells likely involved during the initial stage of drug-induced toxic epidermal necrolysis (TEN). Only limited advances have been made so far in this field. Nevertheless, mitigating EKs metabolic disturbances in TEN probably represent a promising specific treatment of the disease.

Mechanobiology and cell tensegrity: the root of ethnic hair curling?

BACKGROUND: The hair shape, either straight, crimp, or curly, is basically under genetic influence. It is possibly altered by some drugs such as cytostatic agents. In addition, specific innate molecular characteristics are modulated by some cosmetic procedures to reshape the hair shafts. AIM: To revisit the possible implication of mechanobiology and cell tensegrity in shaping ethnic hair. MATERIALS AND METHODS: Optical and scanning electron microscopy of hairs. RESULTS: It is generally held that the cross-section shape of hair is related to differences in the global aspect of the hair shaft. A possible biologic link between these features may rely on shaping cell tensegrity at any portion of the hair shaft. Cell tensegrity encompasses all intrinsic and extrinsic forces responsible for the three-dimensional arrangement of intracellular macromolecules. CONCLUSION: We offer as a hypothesis that the hair shape in part depends on the organization of the cell proliferation in the hair matrix. This review gathers observations supporting the involvement of cell tensegrity in shaping the hair shaft.

Pre-study and in-study validation of a SPE-LC-MS-MS method for the determination of 5-S-cysteinyldopa, a melanoma biomarker, in human plasma.

The incidence of malignant melanoma has increased over the past decades, particularly in Caucasian population. This disease presents defavourable prognosis in terms of survey, especially when detection occurs at the metastatic phase. Reliable analytical methods for biomarker determination are thus an interesting tool in pathology detection and follow-up. In this context, a method using SPE-LC-ESI-MS-MS for the determination of 5-S-cysteinyldopa (5-SCD) in human plasma was optimized. The presence of matrix effect was investigated in details while 5-SCD stability was studied according to FDA requirements for the validation of bioanalytical methods. Pre-study and in-study validations of the entire method were then successfully performed by applying the approach based on total measurement error and accuracy profiles over a concentration ranges from 1.6 to 200 ng/ml. Good results with respect to accuracy, trueness and precision were obtained. The maximum risk of observing future measurements falling outside the acceptance limits during routine analysis was also estimated.

Photoaging under recreational sunbeds.

BACKGROUND: Artificial sources of restricted light wavelength, particularly tanning beds, are progressively gaining importance in photoaging. OBJECTIVE: To assess the kinetics and the long-term evolution of skin pigmentation and tensile functions in sunbed worshippers over a period of 8 years. METHODS: Photoaging was explored in women who were both sunshine and sunbed worshippers. A series of 65 phototype III women aged 31-46 years completed a 100-month survey. Quarterly assessments were performed on the forearms to measure (a) the skin color individual typology angle (ITA°), (b) the extent in mottled subclinical melanoderma (MSM) using the ultraviolet light-enhanced visualization method and (c) the rheological properties of skin. RESULTS: A progressive increase in both skin extensibility and hysteresis was observed, contrasting with a decrease in biologic elasticity. These rheological changes were correlated with the ITA° changes, but not with the MSM extent. The kinetics of evolution of each test variable were distinct over time. DISCUSSION: This work is the first attempt at evaluating the kinetics of changes in physical parameters during a long period of frequent exposures to tanning sunbeds and sunshine for lifestyle purposes. The alterations were quite important in the color, MSM and rheological functions of the skin.

New approaches in light/laser therapies and photodynamic treatment of acne.

Acne is a domain in which the technology and understanding of light/laser therapeutic procedures have advanced considerably. The aim of the paper was to revisit adjunctive physical treatments of acne, including light/laser treatments and photodynamic therapy. This review summarizes findings about such treatment modalities with particular emphasis on efficacy and safety. A number of laser/light-based modalities have been developed to meet the increasing demand for new acne treatments. The current devices correspond, on the one hand, to light-emitting diode therapy and, on the other hand, to the 532-nm potassium titanyl phosphate laser, the 585- and 595-nm pulsed dye laser, the 1450-nm diode laser, the 1320-nm Nd:YAG laser and intense pulsed light. Photodynamic therapy is also available. It is claimed that light/laser treatments might induce a faster response compared with the 1-3 months needed for response to traditional oral and topical treatments. In conclusion, pulsed dye laser shows efficacy in some patients with mild to moderate acne. The relative effectiveness compared with other treatments is unconfirmed; from the published information, evidence-based efficacy assessment of light/laser therapies in acne remains almost impossible.

Intense pulsed-light therapy for proliferative haemangiomas of infancy.

Infantile haemangioma therapy has long been a wait-and-see policy. Since recent development of laser and light therapy, pulsed dye laser has been successfully used for treating superficial haemangiomas. Few studies have been published about treatment with intense pulsed light (IPL) to assess the risk/benefit of IPL in the treatment of infantile haemangiomas during their early proliferative phase. In the present retrospective cohort study, we retrieved data about a series of 14 Caucasian children (median age: 4.8 months) with infantile haemangiomas treated with Photoderm Vasculight flash lamp. All patients experienced a rapid regression of the haemangiomas after 3 treatments on average. Few adverse events were noted, including ulceration and crusts. No residual scarring and cosmetic damages were noticed. Fast growing haemangiomas should be treated with light therapy as soon as possible. This technology is safe, efficient, inducing regression, and preventing any further functional and aesthetic complications. The benefit-risk ratio favours the treatment of most types of haemangiomas which are out of the scope of betablocker administration.

Topical treatment options for drug-induced toxic epidermal necrolysis (TEN).

IMPORTANCE OF THE FIELD: Drug-induced toxic epidermal necrolysis (TEN) is a dreadful skin condition. The mortality rate of 25 - 30% is mainly due to both metabolic failures and septicemia following loss of epidermal integrity. Topical treatments are important options in these patients. AREAS COVERED IN THIS REVIEW: Topical TEN care includes specific bedding, debridement of epidermal necrosis, applications of bioactive skin substitutes or semi-synthetic and synthetic dressings, as well as antiseptic and antibiotic agents. WHAT THE READER WILL GAIN: In the early exudating phase of TEN, the use of airfluidized bed combined with gentle debridement are recommended. Next, an alternating pressure mattress and silver impregnated absorbent dressings should be used. During the re-epithelialization phase, antiseptic or antibiotic creams overlaid with nonadherent dressings favor an optimized moist and bacteria-controlled environment. TAKE HOME MESSAGE: A suitable topical treatment is mandatory in TEN. Skin care procedures must be managed according to the skin condition corresponding to the initial highly exudating/necrotic phase, the secondary moderately exudating stabilized phase and the later re-epidermization phase. Bedding modalities, debridement procedures, applications of bioactive, semi-synthetic and synthetic dressings (silver-impregnated or not) and antiseptic/antibiotic creams should be adapted accordingly.

Facing up to toxic epidermal necrolysis.

Toxic epidermal necrolysis (TEN) is a rare but life-threatening mucocutaneous adverse drug reaction. The disease is characterized by a specific and extensive destruction of the epidermis and mucosal epithelia, particularly of the mouth, genitalia and eyes. The TEN pathomechanism is probably initiated by a toxic drug metabolism inside keratinocytes, leading to a self-activation of apoptosis and necrosis. These events are boosted by additional effects of T lymphocytes and macrophages. At present there is still a lack of validated mainstay treatment for TEN. However, a few treatment modalities have been reported to halt TEN progression in some patients.

Facing towards epidermal stem cells (Review).

Skin contains somatic stem cells that generate keratinocyte, melanocyte and mesenchymal cell lineages. These somatic stem cells have traditionally been thought to be restricted in their differentiation and regeneration potential to the tissues in which they reside. This review focused on epidermal stem cells (ESCs). These cells are distinguished from transitory amplifier cells and post-mitotic cells. ESC are found in the interadnexal epidermis and in the bulge region of hair follicles. A series of ESCs markers are available, but increased sensitivity and specificity require further development.

The therapeutic potential of TNF-alpha antagonists for skin psoriasis comorbidities.

IMPORTANCE OF THE FIELD: Alopecia, psoriatic arthritis, the metabolic syndrome, inflammatory bowel diseases and cardiovascular diseases may occur as skin psoriatic comorbidities. TNF-alpha antagonists are used to treat psoriasis. Adalimumab is one of the recognized active agents for this indication. AREAS COVERED IN THIS REVIEW: The current peer-reviewed publications and presentation of original findings. WHAT THE READER WILL GAIN: Adalimumab is active on recalcitrant psoriasis and some of its comorbidities, particularly arthropathies and Crohn's disease. However, the progression of the radiological alterations is limited with regression of the bony erosions. Psoriatic enthesopathy also regresses. Mortality associated with psoriasis arthropathy is on the decline. Crohn's disease, the most frequent inflammatory bowel comorbidity of psoriasis, is responsive to adalimumab. The effect of adalimumab on the metabolic syndrome and cardiovascular involvement is more erratic. The spectacular effects of adalimumab may be associated with some adverse effects. In particular, despite a marked reduction in the psoriasis area-and-severity index (PASI) score some new acute lesions of cutaneous psoriasis may develop corresponding to paradoxical psoriasis. Other potential adverse effects include infections, granulomas, rapid growth of cancers and occurrence of lymphomas. TAKE HOME MESSAGE: Adalimumab frequently controls moderate-to-severe forms of cutaneous psoriasis and some of its comorbidities.

Immunohistochemical aspects of the fibrogenic pathway in nephrogenic systemic fibrosis.

Nephrogenic systemic fibrosis (NSF) is a rare gadolinium-dependent disorder of the skin and viscera. The aim of this study was to revisit some immunopathologic clues of NSF, including the characterization of glycosaminoglycans, cell tensegrity, and cell proliferation in the dermis. Immunohistochemistry was done using antibodies directed to vimentin, CD34, Factor XIIIa, calprotectin, α-smooth muscle actin, Ulex europaeus agglutinin-1 (UEA-1), and MIB1/Ki67 and to glycosaminoglycans, including CD44 var3, versican, and perlecan. The vimentin+ cell density was markedly increased. The vast majority of them corresponded to CD34+ or Factor XIIIa+ dermal dendrocytes (DD) showing distinct cell tensegrity. CD34+DD were slender, elongated, and usually scattered in the dermis but focally clustered in nodular collections. By contrast, Factor XIIIa+ was plump with squat dendrites showing no evidence for being under mechanical stress. Cells in the vicinity of the microvasculature were rounded and exhibited calprotectin immunoreactivity typical for monocyte/macrophages. The microvasculature highlighted by UEA-1 and α-smooth muscle actin looked unremarkable. The cell proliferation highlighted by the MIB/Ki67 immunoreactivity was unusually high (>20%) in the interstitial stromal cells. Stromal cells enriched in versican were plump, abundant, and seemed interconnected each other by a dense network of dendrites. By contrast, the immunolabeling for perlecan and CD44 var 3 was unremarkable. In conclusion, the cell population involved in NSF seemed phenotypically heterogeneous, and its growth fraction was clearly boosted in the skin. The intracellular load in versican was prominent. The aspect of cell tensegrity did not suggest the influence of mechanical stress putting stromal cells under tension in the dermis.

Angiogenic fast-growing melanomas and their micrometastases.

Malignant melanoma (MM), particularly its fast-growing type, is prone to interstitial, intravascular and extravascular migratory metastases. There is no information linking their growth fraction, the configuration of the MM advancing edge, the extent in vascularity and the propensity to metastatic progression. The objective of this study was to determine the growth fraction, the size of vascularity and the contours of the progression border of 32 fast-growing MM with regard to the presence or absence of a micrometastatic spread inside the skin and overt metastases in the sentinel lymph nodes. In vivo high resolution colorimetry was performed as a clinical estimate of MM vascularity. Euclidean geometry and fractal analysis were used on immunohistochemical sections. The relative microvasculature profile area beneath MM, and the fractal dimension D of the MM frontline were assessed. The MIB/Ki-67 index was determined in MM cells. Value a* of colorimetry was similarly increased in the presence or absence of micro-metastases. No difference in growth fraction was revealed between these neoplasms. Correlations were found between vascularity and angiotropism, and between the micrometastatic process and the sentinel lymph node involvement. By contrast, no correlation was shown between vascularity and the fractal D dimension of the MM advancing edge. In sum, this study establishes a link between the extent of MM growth fraction, vascularity and the presence of dermal and nodal micrometastases in fast-growing MM.

Functionally active macrophage-derived myeloperoxidase in the skin of drug-induced toxic epidermal necrolysis.

BACKGROUND: Drug-induced toxic epidermal necrolysis (TEN) probably results from a complex and specific immune cell reaction involving lymphocytes and macrophages. OBJECTIVE: To assess the functional role of macrophages in TEN. METHODS: Immunohistochemistry was performed on biopsies from early blisters developed in 9 TEN patients. The amount of extracellular myeloperoxidase (MPO) was measured by ELISA in TEN blister fluid and serum. Controls were blister fluids taken from 9 second-degree burns. In addition, 3-chlorotyrosine (a specific marker of MPO activity) was searched for using liquid mass chromatography both in TEN and burn blister fluids. RESULTS: Immunohistochemistry revealed numerous CD68+ macrophages in 8/9 TEN patients; 5-20% of these cells and rare CD15+ neutrophils exhibited MPO immunoreactivity, while keratinocytes were negative. The amount of MPO was significantly higher in TEN blister fluid than in TEN serum, suggesting macrophage production of MPO in the skin. In addition, MPO was significantly more abundant in TEN blister fluid than in burn blister fluid. 3-Chlorotyrosine was detected in 7/9 TEN blister fluids, but in only 2/9 burn blister fluids. DISCUSSION: MPO produced by macrophages was functionally active in most TEN patients, leading to the production of hypochlorous acid, a potent oxidative compound that alters keratinocytes.

New insights in toxic epidermal necrolysis (Lyell's syndrome): clinical considerations, pathobiology and targeted treatments revisited.

Drug-induced toxic epidermal necrolysis (TEN), also known as Lyell's syndrome, is a life-threatening drug reaction characterized by extensive destruction of the epidermis and mucosal epithelia. The eyes are typically involved in TEN. At present, the disease has a high mortality rate. Conceptually, TEN and the Stevens-Johnson syndrome are closely related, although their severity and outcome are different. Distinguishing TEN from severe forms of erythema multiforme relies on consideration of aetiological, clinical and histological characteristics. The current understanding of the pathomechanism of TEN suggests that keratinocytes are key initiator cells. It is probable that the combined deleterious effects on keratinocytes of both the cytokine tumour necrosis factor (TNF)-alpha and oxidative stress induce a combination of apoptotic and necrotic events. As yet, there is no evidence indicating the superiority of monotherapy with corticosteroids, ciclosporin (cyclosporine) or intravenous immunoglobulins over supportive care only for patients with TEN. However, the current theory of TEN pathogenesis supports the administration of a combination of antiapoptotic/antinecrotic drugs (e.g. anti-TNF-alpha antibodies plus N-acetylcysteine) targeting different levels of the keratinocyte failure machinery.