Whole-genome sequencing reveals oncogenic mutations in mycosis fungoides.

The pathogenesis of mycosis fungoides (MF), the most common cutaneous T-cell lymphoma (CTCL), is unknown. Although genetic alterations have been identified, none are considered consistently causative in MF. To identify potential drivers of MF, we performed whole-genome sequencing of MF tumors and matched normal skin. Targeted ultra-deep sequencing of MF samples and exome sequencing of CTCL cell lines were also performed. Multiple mutations were identified that affected the same pathways, including epigenetic, cell-fate regulation, and cytokine signaling, in MF tumors and CTCL cell lines. Specifically, interleukin-2 signaling pathway mutations, including activating Janus kinase 3 (JAK3) mutations, were detected. Treatment with a JAK3 inhibitor significantly reduced CTCL cell survival. Additionally, the mutation data identified 2 other potential contributing factors to MF, ultraviolet light, and a polymorphism in the tumor suppressor p53 (TP53). Therefore, genetic alterations in specific pathways in MF were identified that may be viable, effective new targets for treatment.

Tight junction defects in patients with atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) is characterized by dry skin and a hyperactive immune response to allergens, 2 cardinal features that are caused in part by epidermal barrier defects. Tight junctions (TJs) reside immediately below the stratum corneum and regulate the selective permeability of the paracellular pathway. OBJECTIVE: We evaluated the expression/function of the TJ protein claudin-1 in epithelium from AD and nonatopic subjects and screened 2 American populations for single nucleotide polymorphisms in the claudin-1 gene (CLDN1). METHODS: Expression profiles of nonlesional epithelium from patients with extrinsic AD, nonatopic subjects, and patients with psoriasis were generated using Illumina's BeadChips. Dysregulated intercellular proteins were validated by means of tissue staining and quantitative PCR. Bioelectric properties of epithelium were measured in Ussing chambers. Functional relevance of claudin-1 was assessed by using a knockdown approach in primary human keratinocytes. Twenty-seven haplotype-tagging SNPs in CLDN1 were screened in 2 independent populations with AD. RESULTS: We observed strikingly reduced expression of the TJ proteins claudin-1 and claudin-23 only in patients with AD, which were validated at the mRNA and protein levels. Claudin-1 expression inversely correlated with T(H)2 biomarkers. We observed a remarkable impairment of the bioelectric barrier function in AD epidermis. In vitro we confirmed that silencing claudin-1 expression in human keratinocytes diminishes TJ function while enhancing keratinocyte proliferation. Finally, CLDN1 haplotype-tagging SNPs revealed associations with AD in 2 North American populations. CONCLUSION: Collectively, these data suggest that an impairment in tight junctions contributes to the barrier dysfunction and immune dysregulation observed in AD subjects and that this may be mediated in part by reductions in claudin-1.

Predictors of response to extracorporeal photopheresis in advanced mycosis fungoides and Sézary syndrome.

BACKGROUND: Extracorporeal photopheresis (ECP) has been utilized for more than 20 years to treat cutaneous T-cell lymphoma (CTCL), but a clinical response can take up to 9 months to manifest. This study was undertaken to determine whether clinical features, laboratory values, cytokine levels, or gene expression levels of tumor markers are useful to predict the subsequent response to ECP in CTCL patients with blood involvement. METHODS: Twenty-one patients with CTCL treated with ECP as monotherapy for at least 6 months were retrospectively identified. Laboratory and clinical data and blood obtained at baseline, 3, and 6 months of treatment were used for analysis. RESULTS: In pretreatment blood specimens, a lower percentage of Sézary cells and a higher absolute eosinophil count were associated with a favorable clinical response. Clinical evidence of an early response after 3 months of ECP did not reliably predict a favorable response at 6 months or beyond. Comparison of cytokines, gene transcripts, and other laboratory measures of disease did not correlate with the subsequent clinical response, although lactate dehydrogenase levels tended to decrease progressively in ECP-responsive cases and increase progressively in ECP-non-responsive cases. Additionally, serum levels of TNF-alpha significantly increased from baseline to 6 months of ECP, but was not found to correlate with the clinical response. CONCLUSIONS: Although we found that increased eosinophils and decreased percentage of Sézary cells were associated with a favorable clinical response to ECP, we were not able to identify the predictors of ECP response within the first 3 months of treatment.

Cryptococcal panniculitis in an immunocompromised patient: a case report and review of the literature.

Cryptococcus neoformans is a dimorphic fungus known to cause disease predominately in immuno-compromised patients. It is not uncommon for cryptococcal disease to manifest within the cutaneous tissues of these patients, and it can have drastically varied presentations, from ulcerated nodules to a more subtle cellulitis. We present a patient who underwent a cardiac transplant and developed a fever and mildly erythematous, indurated plaques on his legs and flank several years later. Skin biopsy revealed cryptococcal panniculitis and C neoformans subsequently grew from both the biopsy culture and the cerebrospinal fluid (CSF). This case report highlights the varied and subtle presentations of cutaneous cryptococcosis in immunocompromised patients and encourages a high index of suspicion for this potentially fatal disease in the setting of immunosuppression.

The use of blind skin biopsy in the diagnosis of intravascular B-cell lymphoma.

Intravascular B-cell lymphoma is a rare type of non-Hodgkin's lymphoma that is characterized by a clonal proliferation of lymphoblasts within small blood vessels. Patients present with nonspecific symptoms and are often only given a diagnosis at autopsy. We report a case of intravascular B-cell lymphoma, characterized by pyrexia, anemia, thrombocytopenia, and mental status decline, without obvious cutaneous manifestations, that was diagnosed with blind skin biopsy.

Clinical potential of mechlorethamine gel for the topical treatment of mycosis fungoides-type cutaneous T-cell lymphoma: a review on current efficacy and safety data.

Nitrogen mustard is a chemotherapeutic agent that has a well-documented safety and efficacy profile in the treatment of cutaneous T-cell lymphoma. Development of nitrogen mustard formulations and treatment regimens has been studied extensively over the last 40 years. In the last 5 years, a new gel formulation has been developed that is associated with a decrease in delayed hypersensitivity reactions. The authors in this review found that while the gel formulation may result in a decrease of allergic contact dermatitis, this advantage has been replaced by a higher number of irritant contact reactions and a decrease in complete response rate. The gel formulation has a complete response rate of 13.8%, which is a decrease in efficacy when compared to aqueous-based preparations of similar concentrations.

Latest insights into pathogenesis of mycosis fungoides and cutaneous T-cell lymphoma.

Cutaneous T-cell lymphoma (CTCL) is a rare but increasing malignancy whose protean manifestations necessarily present in the integument, but can also spread to involve blood, lymph nodes and internal organs. We have developed efficacious and varied therapies to treat early and advanced stage disease, but there are still many who suffer tremendously from this illness. Although the pathogenesis of this cancer remains frustratingly elusive, over the last 200 years we have generated a robust body of evidence that points toward possible singular as well as multifactorial etiologies. Combining the historical hypotheses which have focused upon the concept of infectious causes, including carcinogenic genomic viral integration and bacterial superantigenic chronic stimulation as well as industrial/occupational exposure, along with the more recent revelations of both genetic and epigenetic alteration and immune dysregulation, we are closer than ever to understanding the etiology of CTCL. It is through this knowledge and continued research efforts that we will be able to better diagnose, treat, and potentially prevent or cure CTCL.

Successful treatment of recalcitrant chronic idiopathic urticaria with sulfasalazine.

BACKGROUND: Antihistamines are the standard treatment for chronic idiopathic urticaria (CIU). For patients whose urticaria is unresponsive to antihistamines, the treatment options are limited. During the previous decade, there have been several case reports demonstrating success with sulfasalazine therapy. In this article, we present a case series evaluating sulfasalazine therapy for antihistamine-unresponsive CIU. OBSERVATIONS: Nineteen patients with antihistamine-unresponsive CIU were treated with sulfasalazine between 2002 and 2005. During sulfasalazine therapy, 14 patients (74%) reported significant improvement, 4 patients (21%) reported minimal improvement but were not satisfied with their symptom relief, and 1 patient (5%) reported a worsening of symptoms. Of the 13 patients who required systemic steroids to control their urticaria, all were able to reduce or discontinue steroid use during sulfasalazine therapy. Although 7 patients (37%) had adverse effects (eg, nausea, headache, mild or transient leukopenia, and transaminitis) that were thought to be caused by the use of sulfasalazine, they all kept taking the drug. CONCLUSIONS: This case series demonstrates that sulfasalazine can be a successful and safe treatment option for patients with CIU who have not responded adequately to treatment with antihistamines. Sulfasalazine was steroid sparing in all subjects who were steroid dependent.

Cutaneous manifestations of HIV in the era of highly active antiretroviral therapy: an institutional urban clinic experience.

BACKGROUND: Widespread introduction of highly active antiretroviral therapy (HAART) in the mid 1990s has altered the presentation of the cutaneous manifestations associated with HIV infection. OBJECTIVE: Our purpose was to evaluate the use of HAART on the prevalence and spectrum of cutaneous manifestations in HIV-infected patients. METHODS: A study of the initial visits of 897 HIV-infected patients at an urban dermatology clinic between 1996 and 2002 was performed. RESULTS: Folliculitis was the most common cutaneous disorder identified. Patients with CD4-positive cell counts less than 200 cells/mm3 had an increased prevalence of folliculitis and prurigo nodularis, whereas those with HIV viral loads higher than 55,000 copies/mL had a higher prevalence of idiopathic pruritus and candidiasis. Patients not receiving HAART had increased rates of folliculitis and prurigo nodularis. Patients receiving HAART had increased rates of photosensitivity and molluscum contagiosum. LIMITATIONS: This was a cross-sectional study in which temporality was unable to be determined. CONCLUSION: With ongoing therapeutic advancements, the cutaneous manifestations associated with HIV infection will continue to evolve.

Leukocytosis as an independent risk factor for cerebral vasospasm following aneurysmal subarachnoid hemorrhage.

OBJECT: The identification of patients at an increased risk for cerebral vasospasm after subarachnoid hemorrhage (SAH) may allow for more aggressive treatment and improved patient outcomes. Note, however, that blood clot size on admission remains the only factor consistently demonstrated to increase the risk of cerebral vasospasm after SAH. The goal of this study was to assess whether clinical, radiographic, or serological variables could be used to identify patients at an increased risk for cerebral vasospasm. METHODS: A retrospective review was conducted in all patients with aneurysmal or spontaneous nonaneurysmal SAH who were admitted to the authors' institution between 1995 and 2001. Underlying vascular diseases (hypertension or chronic diabetes mellitus), Hunt and Hess and Fisher grades, patient age, aneurysm location, craniotomy compared with endovascular aneurysm stabilization, medications on admission, postoperative steroid agent use, and the occurrence of fever, hydrocephalus, or leukocytosis were assessed as predictors of vasospasm. Two hundred twenty-four patients were treated for SAH during the review period. One hundred one patients (45%) developed symptomatic vasospasm. Peak vasospasm occurred 5.8 +/- 3 days after SAH. There were four independent predictors of vasospasm: Fisher Grade 3 SAH (odds ratio [OR] 7.5, 95% confidence interval [CI] 3.5-15.8), peak serum leukocyte count (OR 1.09, 95% CI 1.02-1.16), rupture of a posterior cerebral artery (PCA) aneurysm (OR 0.05, 95% CI 0.01-0.41), and spontaneous nonaneurysmal SAH (OR 0.14, 95% CI 0.04-0.45). A serum leukocyte count greater than 15 x 10(9)/L was independently associated with a 3.3-fold increase in the likelihood of developing vasospasm (OR 3.33, 95% CI 1.74-6.38). CONCLUSIONS: During this 7-year period, spontaneous nonaneurysmal SAH and ruptured PCA aneurysms decreased the odds of developing vasospasm sevenfold and 20-fold, respectively. The presence of Fisher Grade 3 SAH on admission or a peak leukocyte count greater than 15 x 10(9)/L increased the odds of vasospasm sevenfold and threefold, respectively. Monitoring of the serum leukocyte count may allow for early diagnosis and treatment of vasospasm.

miR-223 regulates cell growth and targets proto-oncogenes in mycosis fungoides/cutaneous T-cell lymphoma.

The pathogenesis of the cutaneous T-cell lymphoma (CTCL), mycosis fungoides (MF), is unclear. MicroRNA (miRNA) are small noncoding RNAs that target mRNA leading to reduced mRNA translation. Recently, specific miRNA were shown to be altered in CTCL. We detected significantly reduced expression of miR-223 in early-stage MF skin, and further decreased levels of miR-223 in advanced-stage disease. CTCL peripheral blood mononuclear cells and cell lines also had reduced miR-223 as compared with controls. Elevated expression of miR-223 in these cell lines reduced cell growth and clonogenic potential, whereas inhibition of miR-223 increased cell numbers. Investigations into putative miR-223 targets with oncogenic function, including E2F1 and MEF2C, and the predicted miR-223 target, TOX, revealed that all three were targeted by miR-223 in CTCL. E2F1, MEF2C, and TOX proteins were decreased with miR-223 overexpression, whereas miR-223 inhibition led to increased protein levels in CTCL. In addition, we showed that the 3'-UTR of TOX mRNA was a genuine target of miR-223. Therefore, reduced levels of miR-223 in MF/CTCL lead to increased expression of E2F1, MEF2C, and TOX, which likely contributes to the development and/or progression of CTCL. Thus, miR-223 and its targets may be useful for the development of new therapeutics for MF/CTCL.

Sodium thiosulfate in the treatment of non-uremic calciphylaxis.

Calciphylaxis is a metastatic calcification-induced vasculopathy that results in the occlusion of small blood vessels. Although calciphylaxis is normally associated with end-stage renal disease, calciphylaxis from non-uremic origin occurs as well. While the number of reports continues to increase, a standard treatment for non-uremic calciphylaxis has yet to be established. Sodium thiosulfate (STS), which has been proven to be effective in the treatment of uremic calciphylaxis, shows promise; however, reports of its use in non-uremic cases are limited. We describe a case of non-uremic calciphylaxis in a patient with normal renal and parathyroid function who had complete resolution of disease after treatment with STS, and we review similar cases in the published work. Based on the successful outcomes detailed in this case series, STS appears to be an effective therapy for non-uremic calciphylaxis.

Activation of epidermal toll-like receptor 2 enhances tight junction function: implications for atopic dermatitis and skin barrier repair.

Atopic dermatitis (AD) is characterized by epidermal tight junction (TJ) defects and a propensity for Staphylococcus aureus skin infections. S. aureus is sensed by many pattern recognition receptors, including Toll-like receptor 2 (TLR2). We hypothesized that an effective innate immune response will include skin barrier repair, and that this response is impaired in AD subjects. S. aureus-derived peptidoglycan (PGN) and synthetic TLR2 agonists enhanced TJ barrier and increased expression of TJ proteins, claudin-1 (CLDN1), claudin-23 (CLDN23), occludin, and Zonulae occludens 1 (ZO-1) in primary human keratinocytes. A TLR2 agonist enhanced skin barrier recovery in human epidermis wounded by tape stripping. Tlr2(-/-) mice had a delayed and incomplete barrier recovery following tape stripping. AD subjects had reduced epidermal TLR2 expression as compared with nonatopic subjects, which inversely correlated (r=-0.654, P=0.0004) with transepidermal water loss (TEWL). These observations indicate that TLR2 activation enhances skin barrier in murine and human skin and is an important part of a wound repair response. Reduced epidermal TLR2 expression observed in AD patients may have a role in their incompetent skin barrier.

Inhibition of histone deacetylase 3 causes replication stress in cutaneous T cell lymphoma.

Given the fundamental roles of histone deacetylases (HDACs) in the regulation of DNA repair, replication, transcription and chromatin structure, it is fitting that therapies targeting HDAC activities are now being explored as anti-cancer agents. In fact, two histone deacetylase inhibitors (HDIs), SAHA and Depsipeptide, are FDA approved for single-agent treatment of refractory cutaneous T cell lymphoma (CTCL). An important target of these HDIs, histone deacetylase 3 (HDAC3), regulates processes such as DNA repair, metabolism, and tumorigenesis through the regulation of chromatin structure and gene expression. Here we show that HDAC3 inhibition using a first in class selective inhibitor, RGFP966, resulted in decreased cell growth in CTCL cell lines due to increased apoptosis that was associated with DNA damage and impaired S phase progression. Through isolation of proteins on nascent DNA (iPOND), we found that HDAC3 was associated with chromatin and is present at and around DNA replication forks. DNA fiber labeling analysis showed that inhibition of HDAC3 resulted in a significant reduction in DNA replication fork velocity within the first hour of drug treatment. These results suggest that selective inhibition of HDAC3 could be useful in treatment of CTCL by disrupting DNA replication of the rapidly cycling tumor cells, ultimately leading to cell death.

Mannan-binding lectin levels and activity are not altered in atopic dermatitis patients with a history of eczema herpeticum.

Background. Eczema herpeticum (EH) is a potentially serious, systemic complication in subjects with atopic dermatitis (AD) caused by herpes simplex virus (HSV). The innate immune dysregulation that predisposes these subjects to cutaneous viral infections is not well understood. We tested the hypothesis that defects in mannan-binding lectin (MBL) may be associated with an increased risk of EH. Methods. We evaluated serum MBL levels and functional activity in 13 AD subjects with a history of EH (EH+) and 21 AD subjects with no history of EH (EH-). MBL levels were detected by enzyme immunoassay. MBL pathway functional activity was evaluated by determining MBL C4b deposition capacity. Results. We found no statistical difference in MBL serum levels or function between EH+ and EH- groups. Conclusion. Considering the limitations of this study (e.g., small samples size) our findings suggest that MBL defects do not play a role in EH.

Atopic dermatitis: a disease caused by innate immune defects?

Atopic dermatitis (AD) is a common chronic inflammatory skin disease that has increased in prevalence over the last half century. A growing body of evidence suggests that there are a variety of defects in the innate immune system that collectively affect the development and severity of AD. The reduction in antimicrobial peptides, diminished recruitment of innate immune cells (PMNs, pDC, and NK cells) to the skin, epithelial barrier disruption, and TLR2 defects are just some of the credible explanations for AD patients' susceptibility to pathogens such as Staphylococcus aureus, herpes simplex virus, and vaccinia virus. Although the focus for several years has been to identify defects in the innate immune system that might explain AD patients' susceptibility to cutaneous pathogens, it has become clear that some innate immune defects might promote inflammation and thereby aggravate or even induce the development of AD. Here we review the innate immune system, and highlight many of the potential innate networks that may be important in AD patients susceptible to cutaneous pathogens.