Intralymphatic histiocytosis comprises M2 macrophages in superficial dermal lymphatics with or without smooth muscles.

Intralymphatic histiocytosis represents a rare reactive disorder, which is characterized by the accumulation of macrophages within lymphatic vessels and observed predominantly in upper extremities. The infiltration and preferential M2 differentiation of macrophage are observed in chronic lymphedema, and lymphedema is considered a causative factor of intralymphatic histiocytosis. However, what causes accumulation of histiocytes in the lymphatic vessels remains unclear, and investigation regarding the characteristics of the macrophages has not been evaluated. We present a case of intralymphatic histiocytosis, in which immunohistochemical staining for both macrophages and lymphatic vessels was performed to evaluate the nature of macrophages within lymphatic vessels and to determine the causative factor. Aggregated macrophages were shown to be M2 macrophages positive for CD68, CD163 and CD206 but negative for inducible nitric oxide synthase. Thick lymphatic vessels positive for D2-40 and α-SMA in the superficial dermis were observed. We speculate that chronic lymphedema leads to hypertrophy of lymphatic vessels with smooth muscle in the superficial dermis, which may be a kind of malformation, and these lymphatic vessels produce some chemokines that induce intralymphatic aggregation of macrophages.

Erosive pustular dermatosis of the scalp-like eruption due to gefitinib: case report and review of the literature of alopecia associated with EGFR inhibitors.

A 69-year-old Japanese woman with multiple brain metastases secondary to non-small-cell lung cancer was treated with radiosurgery, and subsequently started oral gefitinib. Three years later, she presented with erythematous erosive alopecia with pustules on the scalp. A biopsy specimen showed a dense perifollicular infiltration composed of lymphocytes, neutrophils and abundant plasma cells. Methicillin-resistant Staphylococcus aureus was cultured from the lesions; however, treatment with antibiotics was not effective. We diagnosed an eruption resembling erosive pustular dermatosis of the scalp. Although oral steroids did not improve the lesions, the pustules and erythema of the scalp rapidly improved within a few weeks after discontinuation of gefitinib. There have been only 11 case reports of alopecia associated with epidermal growth factor receptor (EGFR) inhibitors including our case. It is noteworthy that all cases were female, and most cases involved the parietal scalp. Moreover, the reduction or discontinuation of the EGFR inhibitors was needed in all cases with erythematous alopecia, which remained as scarring alopecia.

Histological and quantitative polymerase chain reaction-based analysis of Buruli ulcer using mapping biopsy method.

BACKGROUND: In Japan, Buruli ulcer cases are often advanced, requiring surgical treatment. However, extensive debridement is often difficult because of cosmetic and functional sequelae. Moreover, the lesions are complicated and composed of edematous erythema, necrotic ulcer, and erythematous skin lesions caused by a paradoxical reaction, which also make it difficult to perform adequate debridement. METHODOLOGY/PRINCIPAL FINDINGS: We performed quantitative polymerase chain reaction (PCR) analysis for IS2404 using 29 samples taken from mapping biopsy. We evaluated the relationship among mycobacterial burden, histopathological findings, and clinical outcomes using 83 tissue samples taken from mapping biopsy and debrided Buruli ulcer. On quantitative PCR, the Cp values of IS2404 amplification were substantially different in each site. The major histological findings could be divided into massive subcutaneous necrosis with scant inflammatory cell infiltration and dense inflammatory cell infiltration. Of the 84 sites, 34 were subjected to repeated histological evaluations. In these sites, histological necrosis did not disappear over time despite standard antibiotic treatment. In contrast, the ulcers were cured and no recurrences were observed without resecting the 11 biopsied sites that lacked histological necrosis. Although quantitative PCR revealed that a lower Cp value of IS2404 was associated with histological massive necrosis, sites that showed lower Cp values clinically did not always need debridement. CONCLUSION/SIGNIFICANCE: Our descriptive study revealed that the histological findings and amounts of mycobacterial DNA differed according to the sites despite being found in one lesion. Our results showed that the need for surgical debridement in each site was correlated with histological necrosis without inflammatory cell infiltration, as the inflammation is supposed to represent an active host immune response rather than mycobacterial burden. We suggest that the debridement of lesions with histological necrosis in mapping biopsy may be useful for Japanese cases with unsuccessful standard antibiotic treatment to achieve sufficient clinical improvement.

A novel fusion gene of collagen type I alpha 1 (exon 31) and platelet-derived growth factor B-chain (exon 2) in dermatofibrosarcoma protuberans.

Dermatofibrosarcoma protuberans (DFSP) is an uncommon, slow growing, sarcoma of dermal and subcutaneous tissue with an infiltrative growth pattern. Although DFSP has a high rate of local recurrence, it rarely metastasizes. DFSP is characterized by a chromosomal translocation involving the collagen type I a 1 (COL1A1) gene on chromosome 17 and the platelet-derived growth factor B-chain (PDGFB) gene on chromosome 22. Various exons of the COL1A1 gene have been reported to be involved in the fusion with exon 2 of the PDGFB gene. In this study, we examined the COL1A1-PDGFB fusion transcripts using frozen specimens from three patients with DFSP. The molecular biology study with reverse transcriptase polymerase chain reaction (RT- PCR) and sequencing showed that the ends of exons 25, 31, and 45 in the COL1A1 gene were fused with PDGFB. The exon 2 of the PDGFB gene fused with exon 31 of the COL1A1 gene was a novel fusion gene.

A randomized double-blind trial of intravenous immunoglobulin for bullous pemphigoid.

BACKGROUND: Patients with steroid-resistant bullous pemphigoid (BP) require an appropriate treatment option. OBJECTIVE: A multicenter, randomized, placebo-controlled, double-blind trial was conducted to investigate the therapeutic effect of high-dose intravenous immunoglobulin (IVIG; 400mg/kg/day for 5days) in BP patients who showed no symptomatic improvement with prednisolone (≥0.4mg/kg/day) administered. METHODS: We evaluated the efficacy using the disease activity score on day15 (DAS15) as a primary endpoint, and changes in the DAS over time, the anti-BP180 antibody titer, and safety for a period of 57days as secondary endpoints. RESULTS: We enrolled 56 patients in this study. The DAS15 was 12.5 points lower in the IVIG group than in the placebo group (p=0.089). The mean DAS of the IVIG group was constantly lower than that of the placebo group throughout the course of observation, and a post hoc analysis of covariance revealed a significant difference (p=0.041). Furthermore, when analyzed only in severe cases (DAS≥40), the DAS15 differed significantly (p=0.046). The anti-BP180 antibody titers showed no difference between the two groups. CONCLUSION: IVIG provides a beneficial therapeutic outcome for patients with BP who are resistant to steroid therapy.

Regulatory role for Krüppel-like zinc-finger protein Gli-similar 1 (Glis1) in PMA-treated and psoriatic epidermis.

In this study, we analyze the expression and potential function of the Krüppel-like zinc-finger protein Gli-similar protein 1 (Glis1) in normal and inflammatory skin and in the differentiation of epidermal keratinocytes. Glis1 mRNA is not expressed in normal human epidermis, but is significantly induced in psoriatic epidermis and in mouse skin upon treatment with the tumor promoter phorbol-12-myristate-13-acetate (PMA). The expression of Glis1 is restricted to the suprabasal layers. These observations suggest that Glis1 expression is associated with hyperplastic, inflammatory epidermis. Consistent with these findings, Glis1 mRNA is not expressed in undifferentiated or differentiated normal human epidermal keratinocytes (NHEK) in culture, but is dramatically induced after the addition of PMA or interferon gamma. A similar induction of Glis1 mRNA by PMA treatment was observed in the immortalized epidermal keratinocyte cell line NHEK-HPV, whereas PMA did not induce Glis1 in HaCaT cells or in several squamous cell carcinoma cell lines. To obtain insight into its function, Glis1 and a C-terminal deletion mutant Glis1DeltaC were expressed in NHEK-HPV cells and changes in epidermal differentiation and gene expression examined. Microarray analysis revealed that Glis1DeltaC promoted PMA-induced epidermal differentiation, as indicated by increased expression of many differentiation-specific genes. This, in association with its induction in psoriasis, suggests that transcriptional factor Glis1 is involved in the regulation of aberrant differentiation observed in psoriatic epidermis.

GLIS3, a novel member of the GLIS subfamily of Krüppel-like zinc finger proteins with repressor and activation functions.

In this study, we describe the identification and characterization of a novel transcription factor GLI-similar 3 (GLIS3). GLIS3 is an 83.8 kDa nuclear protein containing five C2H2-type Krüppel-like zinc finger motifs that exhibit 93% identity with those of GLIS1, however, little homology exists outside their zinc finger domains. GLIS3 can function as a repressor and activator of transcription. Deletion mutant analysis determined that the N- and C-termini are required for optimal transcriptional activity. GLIS3 binds to the GLI-RE consensus sequence and is able to enhance GLI-RE-dependent transcription. GLIS3(DeltaC496), a dominant-negative mutant, inhibits transcriptional activation by GLIS3 and GLI1. Whole mount in situ hybridization on mouse embryos from stage E6.5 through E14.5 demonstrated that GLIS3 is expressed in specific regions in developing kidney and testis and in a highly dynamic pattern during neurulation. From E11.5 through E12.5 GLIS3 was strongly expressed in the interdigital regions, which are fated to undergo apoptosis. The temporal and spatial pattern of GLIS3 expression observed during embryonic development suggests that it may play a critical role in the regulation of a variety of cellular processes during development. Both the repressor and activation functions of GLIS3 may be involved in this control.

TIP27: a novel repressor of the nuclear orphan receptor TAK1/TR4.

The nuclear orphan receptor TAK1/TR4 functions as a positive as well as a negative regulator of transcription; however, little is known about the factors regulating or mediating its activity. Yeast two-hybrid analysis using the ligand-binding domain (LBD) of TAK1 as bait identified a novel TAK1-interacting protein, referred to as TIP27, which functions as a repressor of TAK1-mediated transactivation. TIP27 is a 27 kDa protein containing two zinc finger motifs. Mammalian two-hybrid analysis showed that TIP27 interacts specifically with TAK1 and not with several other nuclear receptors tested. The region between Asp39 and Lys79 of TIP27, referred to as TAK1-interaction domain (TID), is critical for its interaction with TAK1 while the TAK1-LBD from helix 3 until the C-terminus is required for the optimal interaction with TIP27. Pull-down assays demonstrated that the TIP27 physically interacts with TAK1 and supported the critical importance of the TID. Confocal microscopy showed that in the nucleus, TIP27 and TAK1 co-localize. TIP27 acts as a strong repressor of DR1-dependent transcriptional activation by TAK1. This repression does not involve the inhibition of TAK1 homodimerization or DR1 binding but may be due to an effect on co-activator recruitment by TAK1. Our results indicate that TIP27 functions as a TAK1-selective repressor.

Congenital atrophic dermatofibrosarcoma protuberans detected by COL1A1-PDGFB rearrangement.

BACKGROUND: Atrophic variant of dermatofibrosarcoma protuberans (DFSP) is a distinct form of DFSP. CASE PRESENTATION: Here, we report the case of a 19-year-old woman with a small congenital atrophic plaque on the right precordium. The lesion remained atrophic for more than 10 years. Several years earlier, a portion of the plaque became tuberous and enlarged. Physical examination revealed a 25 × 30 mm erythematous atrophic plaque surrounded by three hard, smooth, and orange-colored nodules of varying sizes on the right precordium, along with visible subcutaneous adipose tissue and cutaneous veins. Biopsy of the nodule and atrophic plaque revealed dense proliferation of spindle-shaped tumor cells from the dermis to the subcutaneous adipose tissue, and positive immunostaining for CD34 and vimentin in addition to negative staining for factor XIIIa and α-smooth muscle actin. Reverse transcription polymerase chain reaction (RT-PCR) of the tumor tissue revealed the presence of a COL1A1-PDGFB fusion gene. Thus, congenital atrophic dermatofibrosarcoma protuberans was diagnosed. No metastasis to the lungs or regional lymph nodes was found on magnetic resonance imaging. Wide local excision and split-thickness skin grafting was performed and neither recurrence nor metastasis has been observed for 5 years and 8 months since the surgery. CONCLUSION: This case indicates that a congenital atrophic lesion could represent a quiescent phase of DFSP. Awareness of this rare condition can aid with early diagnosis and thereby improve the prognosis of DFSP.

Merkel cell carcinoma showing regression after biopsy: Evaluation of programmed cell death 1-positive cells.

We present a cases of Merkel cell carcinoma (MCC) with Merkel cell polyomavirus that showed complete regression after biopsy. The exact mechanism of regression in MCC has remained unclear. It has been reported that apoptosis caused by T-cell immunity was implicated in the regression, and programmed cell death 1 (PD-1), an inhibitory receptor, was expressed in approximately half of tumor-infiltrating T cells in MCC. However, the contribution of PD-1-positive cells for the regression of MCC has not been evaluated. We examined the rate of PD-1-positive cells among the peritumoral mononuclear cells, which showed that the percentage of PD-1-positive cells in the case was significantly lower compared with in MCC without regression. We propose that PD-1-positive cells suppress tumor immunity for MCC, and that reduction of PD-1-positive cells may be associated with tumor regression.

Expression of double-stranded RNA-activated protein kinase in keratinocytes and keratinocytic neoplasia.

Double-stranded RNA-activated protein kinase (PKR) is a interferon-induced protein initially known for its inhibitory effects on cellular and viral protein synthesis. In recent studies, PKR has been shown to be an important participant in a broad array of cellular processes, including signal transduction, differentiation, apoptosis, cell growth, and tumorigenesis. The expression of PKR in normal human keratinocytes (NHEK) was examined, and its expression in several skin lesions was compared immunohistochemically with that of proliferating cell nuclear antigen (PCNA). Expression of PKR mRNA was detected in NHEK without IFNgamma treatment; the level of PKR mRNA increased with IFNgamma treatment for two hours. Immunoblot analysis revealed that the monoclonal anti-PKR antibody reacted specifically with a 68kDa PKR protein in extracts from NHEK. Immunohistochemistry revealed that PKR protein was expressed in normal epidermis and mucosa. PKR expression was not restricted only to suprabasal cells but was also observed in basal cells positive for PCNA. In psoriatic plaques, PKR expression was lower in basal and parabasal keratinocytes and comparable in suprabasal keratinocytes to the levels in normal skin. PKR was partially detected in atypical cells in non-invasive keratinocytic neoplasia but was completely absent from undifferentiated tumor cells of squamous cell carcinoma. The present study demonstrated that PKR protein is constitutively expressed in epidermal and epithelial keratinocytes of normal skin and mucosa and indicated that a loss of PKR is not associated with the malignant transformation itself but with the increased cell proliferative activity and the altered differentiation of keratinocytes.