Global DNA hypomethylation and hypoxia-induced expression of the ten eleven translocation (TET) family, TET1, in scleroderma fibroblasts.

The precise mechanisms of tissue fibrosis have not yet been elucidated in systemic sclerosis (SSc). However, studies of the regulation of DNA methylation, the most widely studied epigenetic mechanism, have confirmed the involvement of the TET family proteins, recently identified DNA demethylases, in the pathogenesis of SSc. The mRNA levels of TET family members were compared in normal and SSc fibroblasts. The effects of hypoxia and siRNA specific to HIF-1α on TET expression were also examined. Global methylation status was analysed by LUMA. The presence of 5-hydroxymethylcytosine (5hmC) in SSc was examined by immunohistochemistry. The level of TET1 mRNA in SSc fibroblasts was elevated by 1.68 fold compared with that of normal fibroblasts, but the expression levels of TET2 and TET3 were comparable between both cell types. The expression levels of DNMT1 and DNMT3B mRNA have a tendency to elevate in SSc fibroblasts. Among TET family members, the expression of TET1 was exclusively induced by hypoxia via HIF-1α-independent pathways in SSc fibroblasts, but not in normal fibroblasts. The methylation level was decreased in SSc fibroblasts relative to normal fibroblasts, and 5hmC was present in dermal fibroblasts of skin sections from patients with SSc. TET1 expression in SSc fibroblasts was abnormally regulated in the hypoxic environment and accompanied by global DNA hypomethylation, suggesting the involvement of aberrant DNA methylation in the pathogenesis of SSc.

A case of rapidly progressive, fatal mycosis fungoides presenting as a haematoma-like lesion.

Mycosis fungoides usually follows an indolent clinical course. We report here a rapidly progressive case of mycosis fungoides with peculiar clinical and histological features, presenting as a haematoma-like mass on the thigh accompanied by multiple reddish brown erythematous lesions on the trunk and extremities. Histopathologically, the erythematous lesions showed epidermotropism of atypical T lymphocytes expressing CD4 and prominent syringotropism without syringometaplasia. The haematoma-like lesion consisted of diffuse and dense infiltrates of medium-to-large-sized pleomorphic lymphocytic cells expressing CD30, suggesting that CD30+ large-cell transformation had occurred. Mycosis fungoides presenting as a haematoma-like lesion is rare and may be a poor prognostic sign.

Skin surface material for detecting human papillomavirus infection of skin warts.

Warts, caused by human papillomavirus (HPV) infection, have various clinical presentations, making them difficult to differentiate from clavus, callus, and sometimes, squamous cell carcinoma. Although skin biopsies are the gold standard, a less-invasive method of examining these lesions is desired. Ninety patients with warts and related diseases, such as clavus and callus, were recruited to explore new differentiation methods using the surface of the warts. DNA was extracted from three types of specimens in each case: surface swab, shaved hyperkeratotic scale, and post-shaved surface swab. Total DNA was successfully extracted from these three specimens and was sufficient for subsequent HPV DNA detection. We analyzed samples for the HPV type and HPV viral load using polymerase chain reaction (PCR). Fifty-five cases were PCR-positive, and HPV1a, 2a, 4, 27, 57, and 65 were detected. The amount of HPV1a DNA produced was significantly greater than that of other HPV types. Regarding the correlation between the clinical diagnosis and HPV detection, the positive agreement rate was 90.9%, the negative agreement rate was 40.0%, and the overall agreement rate was 71.1%. Ten of the 21 cases clinically diagnosed as plantar warts were PCR-negative, especially in elderly patients. This suggests that it is difficult to distinguish plantar warts from clavus and callus in clinical practice. Although the amount of HPV DNA in the removed keratinization scale was highest for all HPV types, HPV detection by swabbing before and after shaving is also useful for follow-up as well as for differential diagnosis.

Identification and analysis of two splice variants of human G2A generated by alternative splicing.

G2A is a G protein-coupled receptor that can be induced by various stressors. G2A is reported to have proton-sensing activity that mediates intracellular inositol phosphate (IP) accumulation with decreasing pH. We previously showed that G2A is also activated by some oxidized free fatty acids such as 9-hydroxyoctadecadienoic acid (9-HODE). In this study, we identified a novel alternative splice variant of G2A (G2A-b) that has a partially different N terminus compared with the G2A originally reported (G2A-a). The two splice variants of G2A show similar tissue distributions, but G2A-b is expressed more abundantly. There was no difference between the two variants in 9-HODE-induced cellular responses, such as intracellular calcium mobilization and GDP/GTP exchange of Galpha protein, and in proton-sensitive IP accumulation. However, G2A-b showed a higher basal activity in terms of IP accumulation. Mutagenesis study revealed that the difference in the basal activity is attributable to the K7 residue that exists only in G2A-a. We further demonstrated that an R42A mutation largely impaired both the basal and proton-sensing activities, but did not affect the 9-HODE-induced intracellular calcium increase. Taken together, we found an additional novel G2A variant (G2A-b) that is the major transcript with functional response to ligand stimulation as well as G2A-a, and succeeded in discriminating proton-sensing and oxidized fatty acid-sensing activities of G2A.

Ceramide induces myogenic differentiation and apoptosis in Drosophila Schneider cells.

Cells exposed to genotoxic stress, such as ionizing radiation and DNA damaging reagents, either arrest the cell cycle to repair the genome, or undergo apoptosis, depending on the extent of the DNA damage. DNA damage also has been implicated in various differentiation processes. It has been reported that gamma-ray exposure or treatment with DNA-damaging agents could induce myogenic differentiation in Drosophila Schneider cells. However, the mechanism underlying this process has been poorly understood. In this study, exposure of Schneider cells to X-rays or energetic carbon ion beams caused increase of TUNEL-positive cells and conversion of round-shaped cells to elongated cells. Both upregulation of genes related to myogenesis and increase of myosin indicate that the radiation-induced morphological changes of Schneider cells were accompanied with myogenic differentiation. Because the intracellular ceramide was increased in Schneider cells after exposure to X-ray, we examined whether exogenous ceramide could mimic radiation-induced myogenic differentiation. Addition of membrane-permeable C(2)-ceramide to Schneider cells increased apoptosis and expression of myogenic genes. These results suggest that ceramide plays important roles in both apoptosis and the radiation-induced myogenic differentiation process.

Leukemia cutis in a patient with acute monocytic leukemia presenting as unique facial erythema.

A 67-year-old woman was referred to our department with a 1-month history of facial exanthemas. She had been diagnosed as having acute monocytic leukemia (French-American-British classification, M5b) based on the histological findings of bone marrow. Physical examination revealed diffuse edematous erythema on her cheeks, eyelids and glabella with scattered reddish papules. Histological examination demonstrated dense infiltration of atypical mononuclear cells in the dermis. Specific cutaneous lesions could occur in acute monocytic leukemia more frequently than in other types of leukemia, but rarely show symmetrical edematous erythema limited to the face.

Analysis of clinical symptoms and ABCC6 mutations in 76 Japanese patients with pseudoxanthoma elasticum.

Pseudoxanthoma elasticum (PXE) is a hereditary disease, causing calcification and degeneration of elastic fibers, which affects the skin, eye, cardiovascular systems and gastrointestinal tract. PXE is caused by mutations in the ABCC6 gene. Neither detailed nor large-scale analyses have been accomplished in Japanese patients with PXE. We, therefore, investigated clinical symptoms and ABCC6 gene mutations in 76 Japanese patients. Japanese PXE patients (n = 76) had a significantly lower incidence of vascular lesions than 505 PXE patients in the Leiden Open Variation Database (LOVD) (38.7% vs 65.1%, respectively; P = 1.34E-06); however, the incidences of the skin, eye, cardiac and gastrointestinal lesion symptoms were not significantly different. Symptom severity scores for skin, eye and vascular lesions, calculated using the Phenodex™ system, were significantly lower in Japanese PXE patients than in LOVD PXE patients. Genetic analysis revealed three nonsense, four frame-shift, one exon deletion and 13 missense mutations in ABCC6 in 73 patients; however, we were unable to detect pathogenic mutations in three patients. Frequent mutations differed between Japanese and LOVD PXE patients. In Japanese PXE patients, the top five mutations accounted for more than 60% of all pathogenic changes, suggesting the presence of founder effects. Consistent with previous reports, no obvious correlations between genotypes and phenotypes were identified in this study. In conclusion, we consider that the milder clinical phenotypes, observed even in older Japanese PXE patients, could be attributed to environmental factors such as dietary habits and lifestyle, as well as genetic background.

Linear lupus erythematosus profundus on the scalp following the lines of Blaschko.

We describe a 10-year-old Japanese girl presenting linear alopecia on the scalp and forehead. Histological examination showed fat degeneration with mucin deposit and periappendageal infiltrate of mononuclear cells. We diagnosed her as having linear lupus erythematodes profundus with a linear configuration following the lines of Blaschko.

Unilateral generalized morphea in childhood.

We report a 6-year-old boy with unilateral generalized morphea distributing on the right side of his lower leg, trunk, and upper arm. A skin biopsy from the right thigh showed accumulation of thick collagen bundles extending from the middle dermis to the subcutaneous fat tissue. The levels of antinuclear antibodies, rheumatoid factor, and anti single-stranded DNA antibody were elevated. No severe deformity or functional disabilities were noted. With topical corticosteroid therapy, the sclerotic skin became gradually softer, and no progression of sclerosis has been noted for one year.

A case of hypersensitivity syndrome due to phenytoin.

We report a 30-year-old female with hypersensitivity syndrome (HS) due to phenytoin. Her disease course was typical with elevation of the antibody titer for human herpes virus 6. Three courses of methylpredonisolone pulse therapy were required to control the disease activity. Since the pathogenic mechanism and treatments for HS have not been established, further clinical analyses are warranted.

Four Japanese cases of dendritic cell neurofibroma with pseudorosettes.

Dendritic cell neurofibroma with pseudorosettes (DCNWPR) is a rare peripheral nerve sheath tumor (PNST). To our knowledge, the only reported case of DCNWPR in Japan was documented by our team. We experienced three additional cases of DCNWPR in our institute since 2007, and report the clinical and histological features of DCNWPR of these Japanese cases. All four patients were adult women, with ages ranging 48-77 years (mean, 63.8). All patients presented with small solitary lesions that were clinically diagnosed as fibroma, melanocytic nevus or mixed tumor of the skin. Three cases were located on the back, and one on the cheek. Histopathologically, well-circumscribed nodules were present in the dermis, and composed of small lymphocyte-like cells with dark nuclei (type I cells) and larger cells with pale vesicular nuclei and abundant eosinophilic cytoplasm (type II cells). Small type I cells were grouped concentrically around the larger type II cells, thereby forming pseudorosettes. Immunohistochemical studies using antibodies against CD57 and S100 protein revealed that type II cells contained a copious cytoplasm endowed with a network of slender dendritic extensions. CD57 should be a useful marker for identifying type II cells because it allows these cells to be stained exclusively. We should recognize DCNWPR with its characteristic histological features such as pseudorosettes and presence of dendritic type II cells as a variant of PNST.

No association of atherosclerosis with digital ulcers in Japanese patients with systemic sclerosis: evaluation of carotid intima-media thickness and plaque characteristics.

Patients with systemic sclerosis (SSc) usually develop Raynaud's phenomenon, persistent digital ischemia and sometimes develop digital ulcers (DU). Several studies have reported an association of carotid artery atherosclerosis with SSc by evaluating carotid intima-media thickness (IMT) in SSc patients. However, none of those studies analyzed the association between DU and carotid artery atherosclerosis in SSc patients. We examined the association of carotid artery atherosclerosis with digital ulcers by comparing SSc patients with (n = 48, 29.5%) and without (n = 206, 70.5%) DU. The demographic and clinical features of the SSc patients showed that young age, male sex, anti-topoisomerase I antibody positivity, severe skin sclerosis, interstitial lung disease complication and cardiac involvements were significantly prevalent in patients with DU. In addition, diffuse cutaneous type, anti-RNA polymerase III antibody positivity and severe skin sclerosis are more frequent in SSc patients with DU at the extensor surface of joints than SSc patients with DU at the digital tip. There were no differences in serum lipid level, carotid IMT or plaque score between SSc patients with and without DU, suggesting that atherosclerotic changes are not primarily involved in the development of DU.

First Japanese case of atypical progeroid syndrome/atypical Werner syndrome with heterozygous LMNA mutation.

Atypical progeroid syndrome (APS), including atypical Werner syndrome (AWS), is a progeroid syndrome involving heterozygous mutations in the LMNA gene encoding the nuclear protein lamin A/C. We report the first Japanese case of APS/AWS with a LMNA mutation (p.D300N). A 53-year-old Japanese man had a history of recurrent severe cardiovascular diseases as well as brain infarction and hemorrhages. Although our APS/AWS patient had overlapping features with Werner syndrome (WS), such as high-pitched voice, scleroderma, lipoatrophy and atherosclerosis, several cardinal features of WS, including short stature, premature graying/alopecia, cataract, bird-like face, flat feet, hyperkeratosis on the soles and diabetes mellitus, were absent. In immunofluorescence staining and electron microscopic analyses of the patient's cultured fibroblasts, abnormal nuclear morphology, an increase in small aggregation of heterochromatin and a decrease in interchromatin granules in nuclei of fibroblasts were observed, suggesting that abnormal nuclear morphology and chromatin disorganization may be associated with the pathogenesis of APS/AWS.

Clinical analysis of leg ulcers and gangrene in rheumatoid arthritis.

Leg ulcers are often complicated in patients with rheumatoid arthritis (RA), however, the etiology is multifactorial. We examined the cases of leg ulceration or gangrene in seven RA patients who were hospitalized over the past 3 years. One patient was diagnosed as having pyoderma gangrenosum. Although vasculitis was suspected in three patients, no histological evidence was obtained from the skin specimens. In these patients, angiography revealed the stenosis or occlusion of digital arteries. In the remaining three patients, leg ulcers were considered to be due to venous insufficiency. Treatment should be chosen depending on the causes of leg ulcers.

The prevalence of Merkel cell polyomavirus in Japanese patients with Merkel cell carcinoma.

BACKGROUND: A novel polyomavirus, the Merkel cell polyomavirus (MCPyV) has been implicated in the pathogenesis of Merkel cell carcinoma (MCC); however, the prevalence of MCPyV in Japan has not been extensively investigated. OBJECTIVE: To clarify the prevalence of MCPyV in Japanese patients with MCC. METHODS: MCPyV DNA was examined by polymerase chain reaction (PCR) in formalin-fixed paraffin-embedded (FFPE) or frozen tissue samples from 26 patients with MCC diagnosed in four medical centers in Japan. Immunohistochemistry was simultaneously performed using a monoclonal antibody against the viral large T (LT) antigen. FFPE samples from basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) were also analyzed as controls. RESULTS: Twenty-three out of 26 cases (88.5%) were positive for MCPyV DNA by PCR. The amplified products harbored 4 patterns of mutations. Phylogenetic analysis demonstrated that one of our strains was closely related to the other Japanese strains previously reported. The LT antigen was expressed in various degrees in 20 of 26 cases (76.9%) by immunohistochemistry. Histological type had little relation to CM2B4 positivity, whereas 3 of 5 trabecular-type tumors showed no staining. The immunoreactivity for CM2B4 did not correlate with the relative viral DNA load. In BCC and SCC, the LT antigen was immunohistochemically positive, but MCPyV DNA was not detected by PCR. The cells around some MCC and non-MCC tumors were stained with CM2B4 with a distribution similar to CD20- and CD45RO- (especially CD8-) positive lymphocytes. CONCLUSION: MCPyV was highly positive in Japanese patients with MCC. It is of note that the positive rate differs depending upon the detection method.

Bosentan for digital ulcers in patients with systemic sclerosis.

Recurrent digital ulcers are manifestations of vascular disease in patients with systemic sclerosis (SSc). We report six patients with severe digital ulcers who were treated with bosentan administered p.o., 62.5-125 mg daily. The mean duration from the diagnosis of SSc to the initiation of bosentan was 9.5 years, and the observation period after bosentan administration was from 7 months to 4.5 years. In case 1, neither new digital ulcers nor Raynaud's phenomenon developed for 4.5 years. In case 2, digital ulcers recurred after the discontinuation of bosentan; however, re-administration of bosentan lead to the improvement. In cases 3-5 with recurrent digital ulcers, no new lesions have developed. In these five patients, pain evaluated by visual analog scale was significantly reduced. In three patients, bosentan was discontinued because of severe liver dysfunction. These results suggest that bosentan is an effective treatment for refractory digital ulcers associated with SSc; however, liver function should be carefully monitored. Compared to the doses of bosentan used to treat pulmonary hypertension, relatively lower doses may effectively control painful digital ulcer/gangrene in patients with SSc.