Newly-Discovered Neural Features Expand the Pathobiological Knowledge of Blastic Plasmacytoid Dendritic Cell Neoplasm

Simple Summary

For the first time, neuronal features are described in blastic plasmacytoid dendritic cell neoplasm (BPDCN) by a complex array of molecular techniques, including microRNA and gene expression profiling, RNA and Chromatin immunoprecipitation sequencing, and immunohistochemistry. The discovery of unexpected neural features in BPDCN may change our vision of this disease, leading to the designing of a new BPDCN cell model and to re-thinking the relations occurring between BPDCN and nervous system. The observed findings contribute to explaining the extreme tumor aggressiveness and also to propose novel therapeutic targets. In view of this, the identification, in this work of new potential neural metastatic inducers might open the way to therapeutic approaches for BPDCN patients based on the use of anti-neurogenic agents.

Abstract

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and highly aggressive hematologic malignancy originating from plasmacytoid dendritic cells (pDCs). The microRNA expression profile of BPDCN was compared to that of normal pDCs and the impact of miRNA dysregulation on the BPDCN transcriptional program was assessed. MiRNA and gene expression profiling data were integrated to obtain the BPDCN miRNA-regulatory network. The biological process mainly dysregulated by this network was predicted to be neurogenesis, a phenomenon raising growing interest in solid tumors. Neurogenesis was explored in BPDCN by querying different molecular sources (RNA sequencing, Chromatin immunoprecipitation-sequencing, and immunohistochemistry). It was shown that BPDCN cells upregulated neural mitogen genes possibly critical for tumor dissemination, expressed neuronal progenitor markers involved in cell migration, exchanged acetylcholine neurotransmitter, and overexpressed multiple neural receptors that may stimulate tumor proliferation, migration and cross-talk with the nervous system. Most neural genes upregulated in BPDCN are currently investigated as therapeutic targets.

Clinical and serological predictors of relapse in pemphigus: a study of 143 patients

BACKGROUND

Pemphigus is an autoimmune bullous disease mediated by autoantibodies targeting epithelial cell-cell adhesion molecules. Predictors of relapse have not yet been clearly identified.

AIMS

To identify factors at diagnosis and during follow-up that could be predictors of relapse.

METHODS

Clinical and immunopathological data at diagnosis, clinical remission and first relapse from patients with pemphigus vulgaris or foliaceus and at least a 36-month follow-up were collected retrospectively. Based on the autoantibody profile at diagnosis, three serological patient subsets were devised: (i) anti-desmoglein (Dsg)1-positive and anti-Dsg3-negative; (iii) anti-Dsg1-negative and anti-Dsg3-positive; and (iii) anti-Dsg1-positive and anti-Dsg3-positive.

RESULTS

Data from 143 patients were collected. No significant differences were found between relapsers (n = 90) and nonrelapsers (n = 53) for time to remission or for anti-Dsg1 and anti-Dsg3 titres at diagnosis and remission. In the analysis of all patients, a higher risk of relapse was found for a body surface area (BSA) score of 3 compared with BSA < 3 (OR = 3.30, 95% CI 1.17-9.28; P = 0.02) and for a positive titre of either anti-Dsg1 or anti-Dsg3 autoantibodies at remission compared with both being negative (OR = 2.42, 95% CI 1.21-4.85, P = 0.01). In patients who were anti-Dsg3-positive and anti-Dsg1-negative at diagnosis, failure to achieve anti-Dsg3 negativity at clinical remission was a significant predictor of relapse (OR = 7.89, 95% CI 2.06-30.21; P < 0.01). Similarly, failure to achieve anti-Dsg1 negativity at clinical remission was a significant predictor of relapse in patients with both anti-Dsg1 and anti-Dsg3 positivity at diagnosis (OR = 5.74, 95% CI 1.15-28.61; P = 0.03), but not in those who were anti-Dsg1-positive/anti-Dsg3-negative at diagnosis (OR = 1.08, 95% CI 0.27-4.30; P = 0.91).

CONCLUSION

Regardless of pemphigus subtype, autoantibody titre negativity at clinical remission in patients classified based on their anti-Dsg1 and anti-Dsg3 profile at diagnosis and BSA were useful tools in predicting relapse.

Deregulation of JAK2 signaling underlies primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma

Primary cutaneous CD8⁺ aggressive epidermotropic cytotoxic T-cell lymphoma (pcAECyTCL) is a rare variant of cutaneous T-cell lymphoma with an aggressive clinical course and a very poor prognosis. Until now, neither a systematic characterization of genetic alterations driving pcAECyTCL has been performed, nor effective therapeutic regimes for patients have been defined. Here, we present the first highresolution genetic characterization of pcAECyTCL by using wholegenome and RNA sequencing. Our study provides a comprehensive description of genetic alterations (i.e., genomic rearrangements, copy number alterations and small-scale mutations) with pathogenic relevance in this lymphoma, including events that recurrently impact genes with important roles in the cell cycle, chromatin regulation and the JAKSTAT pathway. In particular, we show that mutually exclusive structural alterations involving JAK2 and SH2B3 predominantly underlie pcAECyTCL. In line with the genomic data, transcriptome analysis uncovered upregulation of the cell cycle, JAK2 signaling, NF-κB signaling and a high inflammatory response in this cancer. Functional studies confirmed oncogenicity of JAK2 fusions identified in pcAECyTCL and their sensitivity to JAK inhibitor treatment. Our findings strongly suggest that overactive JAK2 signaling is a central driver of pcAECyTCL, and consequently, patients with this neoplasm would likely benefit from therapy with JAK2 inhibitors such as Food and Drug Adminstration-approved ruxolitinib.

Whole-genome analysis uncovers recurrent IKZF1 inactivation and aberrant cell adhesion in blastic plasmacytoid dendritic cell neoplasm

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and highly aggressive hematological malignancy with a poorly understood pathobiology and no effective therapeutic options. Despite a few recurrent genetic defects (eg, single nucleotide changes, indels, large chromosomal aberrations) have been identified in BPDCN, none are disease‐specific, and more importantly, none explain its genesis or clinical behavior. In this study, we performed the first high resolution whole‐genome analysis of BPDCN with a special focus on structural genomic alterations by using whole‐genome sequencing and RNA sequencing. Our study, the first to characterize the landscape of genomic rearrangements and copy number alterations of BPDCN at nucleotide‐level resolution, revealed that IKZF1, a gene encoding a transcription factor required for the differentiation of plasmacytoid dendritic cell precursors, is focally inactivated through recurrent structural alterations in this neoplasm. In concordance with the genomic data, transcriptome analysis revealed that conserved IKZF1 target genes display a loss‐of‐IKZF1 expression pattern. Furthermore, up‐regulation of cellular processes responsible for cell‐cell and cell‐ECM interactions, which is a hallmark of IKZF1 deficiency, was prominent in BPDCN. Our findings suggest that IKZF1 inactivation plays a central role in the pathobiology of the disease, and consequently, therapeutic approaches directed at reestablishing the function of this gene might be beneficial for patients.

Oesophagitis Dissecans Superficialis as the Presenting Sign of Isolated Oesophageal Mucous Membrane Pemphigoid

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Evidence for a role of autoinflammation in early-phase psoriasis

Psoriasis is a common, inflammatory immune-mediated skin disease mainly presenting with plaques whose pathogenesis is based on the central role of the interleukin (IL)-23/IL-17 axis. However, the mechanisms acting in papular lesions of early-phase psoriasis are not fully understood. The aim of this study was to assess the involvement of autoinflammation, a state of sterile inflammation mainly driven by IL-1 over-production that has been recently hypothesized to act in the early phase of disease. Lesional skin of 10 patients with recent onset, untreated psoriasis has been investigated for expression of IL-1β, IL-17, IL-23 and other cytokines involved in the disease in comparison with normal skin of 10 healthy controls using a protein array method. Immunohistochemical phenotyping of inflammatory infiltrate and co-localization experiments with immunofluorescence confocal microscopy were conducted. IL-1β was significantly more expressed in psoriasis than in normal skin (P < 0·0001). The chemokine IL-8 was also over-expressed in psoriasis (P = 0·03) while IL-12, IL-17, IL-23, tumour necrosis factor-α and interferon-γ were only slightly more expressed in psoriasis than in normal skin, without reaching statistical significance. The inflammatory infiltrate consisted mainly of neutrophils with a relevant number of macrophages and dendritic cells and only scattered, predominantly T helper 1 lymphocytes. IL-1β co-localized mainly with CD66b, a neutrophil marker, suggesting that neutrophils were the major source of this cytokine. IL-1β over-expression in combination with low expression of cytokines that are predominant in late-phase plaque psoriasis may support the role of autoinflammation in early-phase disease, possibly paving the way to randomized trials with IL-1 antagonists.

Linear IgA bullous dermatosis in adults and children: a clinical and immunopathological study of 38 patients

BACKGROUND

Linear IgA bullous dermatosis (LABD) is a rare autoimmune subepithelial vesiculobullous disease due to IgA autoantibodies directed against different antigens of the basement membrane zone (BMZ) of the skin and/or mucosae. It affects mainly preschool-aged children and adults, with only few studies on large series. The aim of this study was to assess possible differences between adults and children regarding clinical presentation, immunopathologic features, management and course of the disease.

METHODS

A retrospective review of 38 LABD patients, followed-up from November 2006 to September 2018, was performed.

RESULTS

Of 38 patients, 27 were adults and 11 children. Mean age at diagnosis was 5.4 years and 60.6 years in the pediatric and adult group, respectively. Considering both groups, limbs were the most commonly involved site (73.7%), followed by trunk (55.3%), head (36.8%) and buttocks (13.2%). Interestingly, head (p = 0.008), particularly perioral (p = 0.001), involvement, as well as "string of pearls" arrangement (p = 0.03), were more prevalent in children. Mucosal involvement was seen in 9 (23.7%) patients and was more frequent in children than adults (45.5% vs 14.8%, respectively, p = 0.09). Linear IgA deposits along the BMZ were observed in 30 patients (78.9%), while linear/granular IgA deposits in 8 patients (21.1%). Dapsone was the most commonly used drug (78.9%) and complete remission was achieved in most cases (81.6%).

CONCLUSIONS

Our epidemiological and clinicopathological findings relative to a large cohort of LABD patients are mostly consistent with the literature data. Interestingly, head, notably perioral, involvement and "string of pearls" arrangement occurred more frequently in the paediatric than adult group. The above clinical parameters may be regarded as diagnostic tools for LABD in children.

CD30 expression in a case of intravascular large B-cell lymphoma, cutaneous variant

Intravascular large B-cell lymphoma (IVLBCL) is one of the rarest B-cell non-Hodgkin lymphomas (NHL), with an aggressive clinical behavior and a poor prognosis; in fact, its treatment is still an unmet clinical need, with a 3-year overall survival (OS) rate of 60% to 81%, and a central nervous system relapse rate of 25%. It usually presents as a widespread disease at diagnosis, with multi-organ involvement. Previously considered as a diffuse large B-cell lymphoma variant, it now represents a different extranodal large B-cell lymphoma entity in the last WHO Classification of tumors of hematopoietic and lymphoid tissues. We hereby describe the case of an 84-year-old Italian woman with an IVLBCL, cutaneous variant, who suffered from early relapse after R-COMP chemotherapy regimen, and was therefore treated with a palliative metronomic chemotherapy. Interestingly, neoplastic cells showed CD30 expression at relapse. CD30 positivity has never been reported in this disease so far, and its expression is known to be involved in NF-kB activation. CD30 expression may be further studied as for prognostic and therapeutic significance; in fact, new therapeutic strategies, such as antibody-drug conjugate targeting CD30, are now available.

Detection of IgE autoantibodies in mucous membrane pemphigoid and their association with disease severity

BACKGROUND

Mucous membrane pemphigoid (MMP) is an autoimmune disease characterized by scarring lesions at mucosal sites. Although the pathogenic role of specific IgG and/or IgA has been already demonstrated and the detection of these immunoglobulins is a criterion in the diagnosis of MMP, little is known about IgE role in this disease. Therefore, the main purpose of this study was to assess the presence of circulating and tissue bound IgE in patients with MMP and their possible correlations with clinical presentation and disease course.

METHODS

We conducted a retrospective study on 29 patients affected by MMP, recruited from a single center. Direct and indirect immunofluorescence studies were assessed to analyze the presence of specific IgE directed against the basal membrane zone. For each patient, fluorescence data were compared to clinical features.

RESULTS

Linear deposits of C3, IgG and IgA were present in 86.2%, 62% and 37.9% of cases respectively, while IgE linear deposits were detected in 17 out of 29 patients (58.6%) including one case with isolated IgE positivity. Circulating IgE and IgA anti-BMZ were present in 7 (24.1%) and 5 (17.2%) patients, respectively. Both the presence of circulating IgA and of tissue bound IgE deposits correlated with disease activity index (P<0.014).

CONCLUSIONS

Our results demonstrated the presence of IgE autoantibodies in MMP, particularly in more severe cases. Thus, IgE detection may represent an additional useful diagnostic tool in this disease.

Immunohistochemical expression and prognostic role of CD10, CD271 and Nestin in primary and recurrent cutaneous melanoma

BACKGROUND

CD10, CD271 and Nestin, which are proteins associated with tumor-initiating properties and/or progression potential, have not been specifically studied on malignant melanoma (MM) with cutaneous recurrences.

METHODS

We evaluated the expression of CD10, CD271 and Nestin in 27 tumor samples from 16 patients. These tumor samples corresponded to 6 primary melanomas which developed 11 ITM and 10 primary melanomas without recurrences at 10-year follow-up from specimens obtained from surgical excisions of patients referred to the Unit of Dermatology, Department of Medical-Surgical and Transplant Physiopathology, University of Milan, between 2006 and 2016.

RESULTS

We demonstrated a higher expression of CD271 and Nestin in primary tumors which recurred than control population, Nestin was expressed with significantly higher percentages in primary tumors than recurrences, and CD10 expression was statistically significant correlated with disease-free survival: cases with a lower score recurred lately than cases with higher scores.

CONCLUSIONS

Our preliminary results suggested that CD271 and Nestin can be considered early biomarkers for the development of ITM, Nesting can be useful in differentiating primary MM from cutaneous recurrences and CD10 is associated with a rapid disease progression and may be considered a potential prognostic marker.

Immunohistochemical expression and prognostic role of CD10, CD271 and Nestin in primary and recurrent cutaneous melanoma

BACKGROUND

CD10, CD271 and Nestin, which are proteins associated with tumor-initiating properties and/or progression potential, have not been specifically studied on malignant melanoma (MM) with cutaneous recurrences.

METHODS

We evaluated the expression of CD10, CD271 and Nestin in 27 tumor samples from 16 patients. These tumor samples corresponded to 6 primary melanomas which developed 11 ITM and 10 primary melanomas without recurrences at 10-year follow-up from specimens obtained from surgical excisions of patients referred to the Unit of Dermatology, Department of Medical-Surgical and Transplant Physiopathology, University of Milan, between 2006 and 2016.

RESULTS

We demonstrated a higher expression of CD271 and Nestin in primary tumors which recurred than control population, Nestin was expressed with significantly higher percentages in primary tumors than recurrences, and CD10 expression was statistically significant correlated with disease-free survival: cases with a lower score recurred lately than cases with higher scores.

CONCLUSIONS

Our preliminary results suggested that CD271 and Nestin can be considered early biomarkers for the development of ITM, Nesting can be useful in differentiating primary MM from cutaneous recurrences and CD10 is associated with a rapid disease progression and may be considered a potential prognostic marker.

JAK2-mutated Langerhans cell histiocytosis associated with primary myelofibrosis treated with ruxolitinib

The pathogenesis and cellular origin of Langerhans cell histiocytosis (LCH) are debated. Recently, mutations on MAPK and PI3K pathways have been linked to disrupted cell proliferation in LCH. Janus Kinase 2 (JAK2) mutations play the same role in Philadelphia-negative chronic myeloproliferative neoplasms. We describe the case of a patient affected by JAK2-positive primary myelofibrosis (PMF) who developed a clonally related LCH while in treatment with ruxolitinib. JAK inhibitors are well known to affect function and differentiation of different hematological lineages, including mononuclear phagocytes precursors. Nevertheless, the literature describes cases of LCH clonally associated with non-LCH hematological neoplasm, suggesting how multilinear myeloid neoplasms may arise from bone marrow. Hence, we briefly discuss the possible pathogenic roles of genetic mutations and JAK inhibition therapy in the pathogenesis of LCH and associated neoplasms.

Primary cutaneous acral CD8 positive T-cell lymphoma with extra-cutaneous involvement: A long-standing case with an unexpected progression

Primary cutaneous acral CD8+ T-cell lymphoma (acral CD8+ TCL) is a new provisional entity characterized by acral skin lesions and an indolent course. We describe an extraordinary case characterized by relapsed nodules with CD8+ cytotoxic infiltrates on the left ear. After 35 years, the skin lesions spread to other acral sites, and a mass with the same histological features as the other skin lesions appeared on the nose. Multiple courses of chemotherapy led to stable disease. Histological examinations carried out at different times showed the gradual transformation of the neoplastic cells, with an increased proliferation index. Genomic analysis revealed losses in the regions harboring the genes involved in cell cycle control. This is the first case of an acral CD8+ TCL with a very long history of indolent nodular lesions progressing to extra-cutaneous sites.

Sézary Syndrome in a 17-Year-Old Boy: Clinicopathologic Features and Genomic Profile

We describe the case of a 17-year-old Hispanic boy who had had erythroderma and diffuse lymphadenopathy for approximately 6 months. A diagnosis of Sézary syndrome was made on the basis of the histologic features of the skin; the presence of the same T-cell clone on the skin, blood, and bone marrow; and the high CD4(+) lymphocyte count with an aberrant phenotype in peripheral blood; bone marrow involvement was also present. The patient was treated with systemic gemcitabine and achieved partial remission.

Immunohistochemical Expression of Apoptotic Markers in Drug-Induced Erythema Multiforme, Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are considered to be severity variants of the same disease, which is almost always associated with drug intake. In contrast, erythema multiforme (EM) is a disorder regarded as only rarely caused by drugs. Keratinocyte apoptosis has been shown to play an important part in the pathogenesis of SJS and TEN, whilst its role in EM remains controversial. To determine the expression of apoptosis-associated molecules Fas, Fas ligand (FasL), Bcl-2 and Bax in the above disorders, an immunohistochemical analysis was performed. We studied both lesional skin from thirty patients having drug-induced EM and 5 cases classified within the SJS/TEN spectrum and normal skin samples. We found a keratinocyte overexpression of Fas antigen, an important molecule mediating apoptosis, not only in SJS and TEN but also in EM. Another noteworthy finding was the strong expression of Bcl-2, a protein known as blocking apoptosis, along the basal layer and in the dermal infiltrate both in SJS/TEN and in EM. Taken together, these findings suggest that Fas-dependent keratinocyte apoptosis may play a part in the pathogenesis of both SJS/TEN and EM. Fas-mediated cell death may be partially suppressed by the Bcl-2 protein.

Rash caused by Oryctes nasicornis

We report a case of rash caused by crushing of a male of Oryctes nasicornis (Linnaeus 1758) (Coleoptera, "http:// it. wikipedia. org/ wiki/ Scarabaeidae" \o "Scarabaeidae" Scarabaeidae), popularly known as "European rhinoceros beetle", on the skin of an Italian tourist who developed the reaction during a trip to Turkey. The rash appeared one hour after the crushing of the insect on the skin. The patient was observed one day later, when she returned to Italy. To our knowledge, no similar cases have been reported in the literature.

Detection of Polyomavirus in Merkel cell carcinoma by immunohistochemistry: report of three cases

Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine carcinoma of the skin, arising from pluripotent precursors of Merkel cells. The tumor most frequently affects head and neck of elderly patients. It increases with sun exposure and after immunosuppression and organ transplantation. Because of a possible viral association, interest in MCC has escalated. A new polyomavirus, Merkel cell polyomavirus (MCPyV), was identified and associated to MCC. In support of this hypothesis, we report three new clinical cases of MCC in which we detected MCPyV by immunohistochemistry and provide an update on current thinking about the MCC.

Expression of cytokines, chemokines and other effector molecules in two prototypic autoinflammatory skin diseases, pyoderma gangrenosum and Sweet's syndrome

Pyoderma gangrenosum (PG) and Sweet's syndrome (SS) are two inflammatory skin diseases presenting with painful ulcers and erythematous plaques, respectively; both disorders have a debilitating clinical behaviour and PG is potentially life-threatening. Recently, PG and SS have been included among the autoinflammatory diseases, which are characterized by recurrent episodes of sterile inflammation, without circulating autoantibodies and autoreactive T cells. However, an autoinflammatory pattern clearly supporting this inclusion has never been demonstrated. We studied 16 patients with PG, six with SS and six controls, evaluating, using a sandwich-based protein antibody array method, the expression profile of inflammatory effector molecules in PG, SS and normal skin. The expressions of interleukin (IL)-1 beta and its receptor I were significantly higher in PG (P = 0·0001 for both) and SS (P = 0·004-0·040) than in controls. In PG, chemokines such as IL-8 (P = 0·0001), chemokine (C-X-C motif) ligand (CXCL) 1/2/3 (P = 0·002), CXCL 16 (P = 0·003) and regulated upon activation normal T cell expressed and secreted (RANTES) (P = 0·005) were over-expressed. In SS, IL-8 (P = 0·018), CXCL 1/2/3 (P = 0·006) and CXCL 16 (P = 0·036) but not RANTES were over-expressed, suggesting that chemokine-mediated signals are lower than in PG. Fas/Fas ligand and CD40/CD40 ligand systems were over-expressed in PG (P = 0·0001 for Fas, P = 0·009 for Fas ligand, P = 0·012 for CD40, P = 0·0001 for CD40 ligand), contributing to tissue damage and inflammation, while their role seems to be less significant in SS. Over-expression of cytokines/chemokines and molecules amplifying the inflammatory network supports the view that PG and SS are autoinflammatory diseases. The differences in expression profile of inflammatory effectors between these two disorders may explain the stronger local aggressiveness in PG than SS.

Association of pyoderma gangrenosum, acne, and suppurative hidradenitis (PASH) shares genetic and cytokine profiles with other autoinflammatory diseases

The association of pyoderma gangrenosum, acne, and suppurative hidradenitis (PASH) has recently been described and suggested to be a new entity within the spectrum of autoinflammatory syndromes, which are characterized by recurrent episodes of sterile inflammation, without circulating autoantibodies and autoreactive T-cells. We conducted an observational study on 5 patients with PASH syndrome, analyzing their clinical features, genetic profile of 10 genes already known to be involved in autoinflammatory diseases (AIDs), and cytokine expression pattern both in lesional skin and serum. In tissue skin samples, the expressions of interleukin (IL)-1β and its receptors I and II were significantly higher in PASH (P = 0.028, 0.047, and 0.050, respectively) than in controls. In PASH patients, chemokines such as IL-8 (P = 0.004), C-X-C motif ligand (CXCL) 1/2/3 (P = 0.028), CXCL 16 (P = 0.008), and regulated on activation, normal T cell expressed and secreted (RANTES) (P = 0.005) were overexpressed. Fas/Fas ligand and cluster of differentiation (CD)40/CD40 ligand systems were also overexpressed (P = 0.016 for Fas, P = 0.006 for Fas ligand, P = 0.005 for CD40, and P = 0.004 for CD40 ligand), contributing to tissue damage and inflammation. In peripheral blood, serum levels of the main proinflammatory cytokines, that is, IL-1β, tumor necrosis factor-α, and IL-17, were within the normal range, suggesting that in PASH syndrome, the inflammatory process is mainly localized into the skin. Four out of our 5 PASH patients presented genetic alterations typical of well-known AIDs, including inflammatory bowel diseases, and the only patient lacking genetic changes had clinically evident Crohn disease. In conclusion, overexpression of cytokines/chemokines and molecules amplifying the inflammatory network, along with the genetic changes, supports the view that PASH syndrome is autoinflammatory in origin.

Prevalence of Borrelia burgdorferi infection in a series of 98 primary cutaneous lymphomas

Borrelia burgdorferi has been variably associated with different forms of primary cutaneous lymphoma. Differences in prevalence rates among reported studies could be a result of geographic variability or heterogeneity in the molecular approaches that have been employed. In the present study, we investigated the prevalence of Borrelia burgdorferi sensu lato DNA in diagnostic tissue samples from fresh cutaneous biopsies of 98 primary cutaneous lymphomas and 19 normal skin controls. Three different polymerase chain reaction (PCR) protocols targeting the hbb, flagellin, and Osp-A genes were used. Direct sequencing of both sense and antisense strands of purified PCR products confirmed the specificity of the amplified fragments. Sequence specificity was assessed using the Basic Local Alignment Search Tool, and MultAlin software was used to investigate the heterogeneity of target gene sequences across the different samples. Borrelia DNA was not detected in 19 controls, 23 cases of follicular lymphoma, 31 cases of extranodal marginal zone lymphoma, or 30 cases of mycosis fungoides. A single case of 14 diffuse large B-cell lymphoma cases was positive for B. burgdorferi. This study does not support a pathogenic role of B. burgdorferi in primary cutaneous B- and T-cell lymphomas from areas nonendemic for this microorganism and the consequent rationale for the adoption of antibiotic therapy in these patients.

Three cases of primary cutaneous lymphoblastic lymphoma: microarray-based comparative genomic hybridization and gene expression profiling studies with review of literature

Lymphoblastic lymphoma (LBL) is a neoplasm of precursor B- or T-lymphocytes, and primary skin involvement is uncommon. The aim of the study was to review all reported primary cutaneous (PC)-LBLs and to examine three new cases to better characterize this neoplasm. Two of our patients showed a pre-B phenotype (PC-B-LBL) and one a never-reported pre-T phenotype (PC-T-LBL). The patient with PC-T-LBL showed an aggressive course, while those with PC-B-LBL showed a complete remission (CR) after polychemotherapy. Cytogenetic analysis and gene expression profiling (GEP) were performed on one case of PC-B-LBL and on that of PC-T-LBL. A specimen of PC-B-LBL and two specimens (early and late stage) of PC-T-LBL were investigated by microarray-based comparative genomic hybridization (CGH). All specimens revealed trisomy of chromosome 4. PC-T-LBL showed a gain of 1p36.33-p22.1 in the early stage and multiple chromosome gains/losses in the late stage. Our data suggest that trisomy 4 could be detected early in LBL and gain of 1p36.33-p22.1 could be an interesting marker in PC-T-LBL. LBL is an aggressive disease but, only in B-LBL, the cutaneous presentation seems to be a favorable prognostic factor and polychemotherapy is the best therapeutic approach. We suggest that PC-LBL should be included as a provisional clinicopathologic entity in future cutaneous lymphoma classification.

Inflammatory cells, cytokines and matrix metalloproteinases in amicrobial pustulosis of the folds and other neutrophilic dermatoses

Amicrobial pustulosis of the folds (APF) is a rare cutaneous disease characterized by relapsing sterile pustules frequently associated with autoimmune disorders. Although APF pathophysiology is still undefined, scattered reports suggest involvement of neutrophils. The aim of the present study is to evaluate the role of the skin inflammatory infiltrate, selected multifunctional cytokines and effectors of tissue damage in APF and other neutrophilic dermatoses. We studied, by immunohistochemical methods, inflammatory cell markers (CD3, CD163, myeloperoxidase), cytokines (TNF-alpha, IL-8, IL-17), metalloproteinases (MMP-2, MMP-9) and vascular-endothelial-growth-factor (VEGF) in lesional skin from six patients with APF, 11 with pyoderma gangrenosum (PG), 7 with Sweet's syndrome, and in 20 normal skin samples. Immunoreactivities of CD3, CD163, myeloperoxidase, TNF-alpha, IL-8, IL-17, MMP-2, MMP-9 and VEGF were significantly higher in APF, PG and Sweet's syndrome than in controls (p=0.0001). IL-8 was more expressed in PG than in APF (P=0.002) and Sweet's syndrome (p=0.001). In APF, MMP-9 reactivity was higher than in Sweet's syndrome (p=0.035), but less intense than in PG (p=0.020). Our study supports the role of proinflammatory cytokines/chemokines and MMPs as important effectors for the tissue damage in APF similarly to classic neutrophilic dermatoses.

Activation of coagulation in bullous pemphigoid and other eosinophil-related inflammatory skin diseases

Bullous pemphigoid (BP) is a skin disease caused by autoantibodies to hemidesmosomal proteins BP180 and BP230, with eosinophils participating in blister formation. Tissue factor (TF), the initiator of coagulation, is embodied within the eosinophil granules and exposed upon activation. We evaluated the coagulation activation in patients with BP (63), chronic urticaria (CU; 20), atopic dermatitis (AD; 14), cutaneous drug reactions (CDRs; six), psoriasis (20), dermatitis herpetiformis (DH; four) and primary cutaneous T cell lymphoma (CTCL; five), and in 40 healthy controls. Prothrombin fragment F1+2 and d-dimer (coagulation markers) were measured by enzyme-linked immunosorbent assay (ELISA) in all plasma samples and BP blister fluid. Skin TF expression was evaluated immunohistochemically in the patients and 20 controls. F1+2 and d-dimer levels were higher in BP plasma than in control plasma (P = 0·0001 for both), and dramatically high in blister fluid; both correlated positively with disease severity, esinophil counts and anti-BP180 antibodies (P = 0·006-0·0001). Plasma F1+2 and d-dimer levels were higher in the CU, AD and CDR patients than in controls (P = 0·0001 for all), but normal in the psoriasis, DH and CTCL patients. Skin TF was expressed in the BP (P = 0·0001), CU (P = 0·0001), AD (P = 0·001) and CDR patients (P = 0·01), but not in the psoriasis, DH or CTCL patients. Co-localization confocal microscopy studies confirmed eosinophils as the source of TF in 10 BP patients. The coagulation cascade is activated in BP and other eosinophil-mediated skin disorders, but not in non-eosinophil driven conditions. This hypercoagulability may contribute to inflammation, tissue damage and, possibly, thrombotic risk.

Cutaneous T-cell/histiocyte-rich B-cell lymphoma: a case report and review of the literature

BACKGROUND

T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) primarily presenting on the skin is an extremely rare entity with only sporadic cases reported in the literature.

METHODS

We here report an extraordinary case of primary cutaneous THRLBCL with self-healing and 24 months of follow-up.

RESULTS

The lesion was a dermohypodermal/subcutaneous circumscribed ulcerated nodosity. Histological examination with immunohistochemical, molecular analysis and comparative genomic hybridization were performed. A complete staging was negative for secondary involvement.

CONCLUSION

Our case is remarkable because it is the second well-documented primary cutaneous THRLBCL in which we observed a complete self-regression of skin lesions without recurrences or dissemination of the disease. According to the literature, we highlight that the tumoral microenvironment, in our case, could play a relevant role in stopping lymphoma growth. Furthermore, this case supports the observation that THRLBCL primarily presenting on the skin shows an overall good prognosis.

C/EBPδ gene targets in human keratinocytes

C/EBPs are a family of B-Zip transcription factors -TFs- involved in the regulation of differentiation in several tissues. The two most studied members -C/EBPα and C/EBPβ- play important roles in skin homeostasis and their ablation reveals cells with stem cells signatures. Much less is known about C/EBPδ which is highly expressed in the granular layer of interfollicular epidermis and is a direct target of p63, the master regular of multilayered epithelia. We identified C/EBPδ target genes in human primary keratinocytes by ChIP on chip and profiling of cells functionally inactivated with siRNA. Categorization suggests a role in differentiation and control of cell-cycle, particularly of G2/M genes. Among positively controlled targets are numerous genes involved in barrier function. Functional inactivation of C/EBPδ as well as overexpressions of two TF targets -MafB and SOX2- affect expression of markers of keratinocyte differentiation. We performed IHC on skin tumor tissue arrays: expression of C/EBPδ is lost in Basal Cell Carcinomas, but a majority of Squamous Cell Carcinomas showed elevated levels of the protein. Our data indicate that C/EBPδ plays a role in late stages of keratinocyte differentiation.

Medallion-like dermal dendrocyte hamartoma: a case misdiagnosed as neurofibroma

Medallion-like dermal dendrocyte hamartoma is a rare congenital lesion, comprised of a benign dermal proliferation of fusiform cells that stain positive for CD34, often positive for factor XIIIa, and negative for S100. It has a highly characteristic clinical presentation consisting of a well-circumscribed atrophic and wrinkled patch located on the upper trunk or neck that remains stable with time. We report a case of an 11-year-old boy with a typical medallion-like dermal dendrocyte hamartoma on the nape of the neck that was previously misdiagnosed as neurofibroma on the basis of initial histological examination that was later reevaluated due to lack of clinical correlation. Three previously-reported cases of medallion-like dermal dendrocyte hamartoma also have had a previous histological misdiagnosis of probable neurofibroma; other reported cases have been misdiagnosed as congenital atrophic dermatofibrosarcoma protuberans. Clinical correlation and immunostaining are particularly important for the recognition of this rare benign lesion.

Role of inflammatory cells, cytokines and matrix metalloproteinases in neutrophil-mediated skin diseases

Pyoderma gangrenosum (PG) is a rare, immune-mediated inflammatory skin disease presenting with painful ulcers having undermined edges. Less commonly, bullous and vegetative variants exist. Histology consists of a neutrophil-rich dermal infiltrate. We characterized immunohistochemically the infiltrate in different variants of PG and in another neutrophilic dermatosis as Sweet's syndrome. We studied 21 patients with PG, eight with Sweet's syndrome and 20 controls, evaluating skin immunoreactivity for inflammatory cell markers (CD3, CD163 and myeloperoxidase), cytokines [tumour necrosis factor (TNF)-α, interleukin (IL)-8 and IL-17], metalloproteinases (MMP-2 and MMP-9) and vascular endothelial growth factor (VEGF). Immunoreactivities of CD3, CD163, myeloperoxidase, TNF-α, IL-8, IL-17, MMP-2, MMP-9 and VEGF were significantly higher in both PG and Sweet's syndrome than in controls (P=0·0001). Myeloperoxidase (neutrophil marker), IL-8 (cytokine chemotactic for neutrophils) and MMP-9 (proteinase-mediating tissue damage) were expressed more significantly in both ulcerative and bullous PG than in vegetative PG as well as in Sweet's syndrome (P=0·008-P=0·0001). In ulcerative PG, the expression of CD3 (panT cell marker) and CD163 (macrophage marker) were significantly higher in wound edge than wound bed (P=0·0001). In contrast, the neutrophil marker myeloperoxidase was expressed more significantly in wound bed than wound edge (P=0·0001). Our study identifies PG as a paradigm of neutrophil-mediated inflammation, with proinflammatory cytokines/chemokines and MMPs acting as important effectors for the tissue damage, particularly in ulcerative and bullous PG where damage is stronger. In ulcerative PG, the wound bed is the site of neutrophil-recruitment, whereas in the wound edge activated T lymphocytes and macrophages pave the way to ulcer formation.

Prothrombotic state in Churg-Strauss syndrome: a case report

An increased risk of thrombosis has been described in patients with hypereosinophilic syndromes, including Churg-Strauss syndrome (CSS). We report the case of a 43-year-old man with CSS who presented with asthma, pansinusitis, blood eosinophilia (9650/microL), peripheral neuropathy, cutaneous eosinophilic vasculitis, and a positive result for antineutrophil cytoplasmic antibodies. An analysis of plasma during active disease revealed elevated levels of prothrombin fragment 1+2 (marker of thrombin generation) (832 pM; normal range, 68-229 pM) and D-dimer (marker of fibrin degradation) (2300 ng/mL; normal range, 130-250 ng/mL), which indicate an increased risk of thrombosis. Both parameters returned to normal values during remission after immunosuppressive treatment. Skin histology showed leukocytoclastic vasculitis with numerous eosinophils in the dermal infiltrate. Immunohistochemistry revealed expression of tissue factor by skin-infiltrating eosinophils, as confirmed by colocalization with eosinophil cationic protein, a classic marker of eosinophil granulocytes. In conclusion, we present a patient with active CSS and a prothrombotic state that reverted during remission achieved by immunosuppressive therapy.

Plasma levels and skin-eosinophil-expression of vascular endothelial growth factor in patients with chronic urticaria

BACKGROUND

Although chronic urticaria (CU) is often regarded as autoimmune in nature, only less than 50% of sera from CU patients contain histamine-releasing autoantibodies. This suggests that other factors may contribute to its pathogenesis. We evaluated the possible involvement of vascular endothelial growth factor (VEGF), one of the major mediators of vascular permeability, in CU.

METHODS

Eighty consecutive adult patients with CU and 53 healthy subjects were studied. VEGF and prothrombin fragment F(1+2) were measured by enzyme immunoassays. Autologous plasma skin test (APST) was performed in CU patients and, in six of them, skin biopsy specimens were taken from wheals to evaluate the immunohistochemical expression of VEGF and eosinophil cationic protein (ECP).

RESULTS

Plasma VEGF concentrations were higher in CU patients (8.00 +/- 0.90 pmol/l) than in controls (0.54 +/- 0.08 pmol/l) (P = 0.0001) and tended to parallel both the severity of CU and to correlate with F(1+2) levels. APST was positive in 85.1% of patients. VEGF concentration was significantly higher in APST-positive than in APST-negative patients (P = 0.0003). Immunohistochemically, all specimens from patients with CU showed a strong expression of VEGF (P = 0.002) that colocalized with ECP, a classic eosinophil marker.

CONCLUSIONS

VEGF plasma levels are elevated in CU and parallel the disease severity. This supports a possible role of this molecule in CU pathophysiology. Eosinophils are the main cellular source of VEGF in CU lesional skin.

Coagulation activation in autoimmune bullous diseases

The main autoimmune blistering skin disorders are pemphigus vulgaris (PV) and bullous pemphigoid (BP). They differ in the inflammatory infiltrate, which is more intense in BP. Inflammation is known to activate coagulation in several disorders. Local and systemic activation of coagulation was evaluated in BP and PV. We studied 20 BP patients (10 active and 10 remittent), 23 PV patients (13 active and 10 remittent) and 10 healthy subjects. The coagulation markers prothrombin fragment F1+2 and D-dimer were measured by enzyme-immunoassays in plasma. The presence of tissue factor (TF), the main initiator of blood coagulation, was evaluated immunohistochemically in skin specimens from 10 patients with active PV, 10 patients with active BP and 10 controls. Plasma F1+2 and D-dimer levels were significantly high in active BP (P = 0.001), whereas in active PV the levels were normal. During remission, F1+2 and D-dimer plasma levels were normal in both BP and PV. TF immunoreactivity was found in active BP but neither in active PV nor in normal skin. TF reactivity scores were higher in active BP than in controls or active PV (P = 0.0001). No difference in TF scores was found between active PV and controls. BP is associated with coagulation activation, which is lacking in PV. This suggests that BP but not PV patients have an increased thrombotic risk. The observation that thrombotic complications occur more frequently in BP than in PV further supports this view.

Expression of tissue factor by eosinophils in patients with chronic urticaria

BACKGROUND

Although several cases of chronic urticaria (CU) are currently regarded as autoimmune in origin, associated with histamine-releasing autoantibodies, an activation of blood coagulation via tissue factor (TF) and a strong expression of TF in lesional skin have been described. Eosinophils, which are involved in CU skin lesions, have recently been demonstrated as the major source of TF in human blood. We assessed whether eosinophils are the cellular source of TF in CU skin lesions.

METHODS

Twenty patients with severe CU were studied. Skin biopsy specimens were taken from wheals. The control group consisted of specimens of perilesional normal skin from different types of skin tumours (10) and various skin disorders with non-eosinophilic infiltrates, including leukocytoclastic vasculitis (7), lichen planus (8) and mastocytosis (3). TF expression was evaluated by immunohistochemical methods using an anti-TF monoclonal antibody. Co-localization of TF and eosinophil cationic protein, a classic cell marker of eosinophils, was investigated by double-staining studies using 2 specific monoclonal antibodies in the 4 specimens showing the highest TF reactivity scores.

RESULTS

All specimens from patients with CU clearly showed TF expression that was absent in all normal control specimens (p = 0.0001) and in the skin disorders with non-eosinophilic infiltrates (p = 0.001-0.0001). The double-staining experiments for TF and eosinophil cationic protein clearly showed that the TF-positive cells were eosinophils.

CONCLUSIONS

Eosinophils are the main source of TF in CU lesional skin. This finding highlights the role of these cells in the pathophysiology of CU and might pave the way for new therapeutic strategies.

Treatment of Refractory Pemphigus with the Anti-CD20 Monoclonal Antibody (Rituximab)

BACKGROUND

Pemphigus is a severe blistering disorder caused by autoantibodies to desmogleins 1 and 3. Because some patients with pemphigus never enter into remission, new immunosuppressants are warranted. Rituximab is a chimeric monoclonal antibody binding to the CD20 antigen on B cells, which proved to be effective in recalcitrant pemphigus.

OBJECTIVES

To evaluate the efficacy and safety of rituximab in refractory pemphigus and to investigate its effects on the autoantibody profile.

PATIENTS AND METHODS

Six patients with recalcitrant pemphigus were treated. Rituximab was administered intravenously at a dosage of 375 mg/m2 body surface once weekly for 4 weeks.

RESULTS

Three pemphigus foliaceus patients and 1 with mucocutaneous pemphigus vulgaris (PV) showed complete response over a follow-up period of up to 18 months. In one oral PV, control of the disease was achieved using pulse therapy with cyclophosphamide following rituximab withdrawal. In one PV with vegetating features, good improvement was obtained after 6 rituximab infusions. All patients tolerated the treatment well. Anti-desmoglein autoantibodies significantly decreased only in pemphigus foliaceus.

CONCLUSIONS

This study highlights that rituximab is a valuable drug for refractory pemphigus, although the response of mucous membranes and cutaneous folds may be delayed.

Activation of the tissue factor pathway of blood coagulation in patients with chronic urticaria

BACKGROUND

In patients with chronic urticaria (CU), plasma shows signs of thrombin generation and autologous plasma skin tests score positive in as many as 95% of cases.

OBJECTIVE

To evaluate the initiators of blood coagulation that lead to thrombin generation and fibrinolysis in CU.

METHODS

Activated factor VII, activated factor XII, fragment F(1+2), and D-dimer plasma levels were measured in 37 patients with CU and 37 controls. Skin specimens from 10 patients with CU and 10 controls were tested for tissue factor immunohistochemically.

RESULTS

Mean F(1+2) levels were higher in patients than controls (2.54 [SD 2.57] nmol/L vs 0.87 [0.26] nmol/L; P < .001); disease activity was moderate or severe in 9 of 11 (82%) and 9 of 26 (35%) patients showing high or normal F(1+2) levels, respectively (P < .025). Mean D-dimer plasma levels were higher in patients than controls (329 [188] ng/mL vs 236 [81] ng/mL; P < .01); disease activity was moderate or severe in 6 of 8 (75%) and 11 of 29 (38%) showing elevated or normal plasma D-dimer levels (P = NS). Factor VIIa levels were higher in patients than controls (2.86 ng/mL [0.66] vs 1.97 ng/mL [0.65]; P < .001). Activated factor VII and F(1+2) levels were correlated (r = 0.529; P = .008). Tissue factor reactivity was observed only in CU skin specimens.

CONCLUSION

The extrinsic pathway of clotting cascade is activated in CU. Disease severity is associated with the activation of the coagulation cascade.

CLINICAL IMPLICATIONS

The involvement of the coagulation pathway in CU opens new perspectives for a better understanding of the pathogenesis and, possibly, for the treatment of this disease.