B-Myb enhances proliferation and suppresses differentiation of keratinocytes in three-dimensional cell culture

B-Myb (Mybl2) is a member of the Myb gene family of transcription factors involved in the control of cell growth, differentiation, and apoptosis. The effects of B-Myb on keratinocyte proliferation and differentiation have not yet been clarified. The present study was performed to examine the role of B-Myb in proliferation and differentiation of the spontaneously immortalized human skin keratinocyte cell line HaCaT and normal human keratinocytes with formation of a stratified epidermoid structure in air-liquid interface three-dimensional culture. B-Myb was expressed specifically in undifferentiated normal keratinocytes and downregulated during differentiation. The constitutive overexpression of B-Myb in HaCaT cells during air exposure-induced differentiation resulted in an undifferentiated phenotype, i.e., thickening of the stratified layers, suppression of differentiation marker expression, and retention of proliferative activity with activation of cell cycle regulatory proteins in the S and G2/M phases. In contrast, suppression of B-Myb caused their downregulation and constrained proliferation with retention of differentiation capacity. These findings suggested that B-Myb plays an important role in maintenance of the undifferentiated phenotype of keratinocytes in the basal epidermal layer.

A case of sterile transient neonatal pustulosis presenting with large flaccid pustules

We describe a female neonate with large flaccid pustules on her trunk and extremities. Cultures were negative, and a Wright-stained smear of pustule contents showed numerous eosinophils (>90%). The pustules resolved without leaving pigmentation after 2 weeks. We diagnosed this case as sterile transient neonatal pustulosis.

High-grade mucoepidermoid carcinoma of the columella successfully reconstructed using bilateral nasolabial flaps set up in a sandwich shape and an auricular cartilage graft after surgical resection

Mucoepidermoid carcinoma (MEC) usually originates from the salivary glands. However, there has been no report on mucoepidermoid carcinoma of the columella. In this study, we report the case of a high-grade MEC of the columella that was successfully reconstructed after surgical resection with bilateral nasolabial flaps set up in a sandwich shape and an auricular cartilage graft. A 66-year-old man presented with a nodule on the columella. Histological findings were suggestive of a high-grade mucoepidermoid carcinoma. Wide excision was performed, and the defects of the columella and the nasal floor were reconstructed with bilateral nasolabial flaps set up in a sandwich shape and an auricular cartilage graft. The postoperative cosmetic result was good with excellent tissue texture. The reconstructed columella had an appropriate, not bulky, width as well as satisfactory height and depth. This reconstructive technique is particularly useful for correcting the large defect of the columella with nasal septum and/or nasal floor defects.

NF1 gene silencing induces upregulation of vascular endothelial growth factor expression in both Schwann and non-Schwann cells

Neurofibromatosis type I (NF1) is associated with typical hypervascular tumors, including neurofibroma, glioma, malignant peripheral nerve sheath tumors (MPNST) and glomus tumors. Previously, we and other groups reported that neurofibromas showed high-level expression of vascular endothelial growth factor (VEGF), a potent angiogenic factor involved in neovascularization. However, the molecular mechanism underlying the upregulation of VEGF in neurofibromas remains unclear. In this study, we examined the effects of Nf1 gene silencing on VEGF expression in Schwann cell and non-Schwann cell line and the upstream mTOR-HIF-1α - VEGF pathway in Schwann cell line. The results indicated that Nf1 gene silencing by lentiviral-mediated RNA interference resulted in elevated expression of VEGF, HIF-1α and phosphorylated mTOR at the protein level. The results obtained from Nf1 gene silencing in murine Schwann cell line analogously suggest that NF1 gene haploinsufficiency in human tumor Schwann cells may directly elicit upregulation of VEGF expression without the tumor microenvironment by activation of the mTOR-HIF-1α - VEGF pathway. We also showed that interleukin-6 is upregulated in Nf1 gene knock-down Schwann cells at the protein level.

Psoriasiform eruption associated with graft-versus-host disease

Graft-versus-host disease (GVHD) is a frequent complication of bone marrow transplantation (BMT) that can be classified as acute or chronic. Characteristic cutaneous manifestations of acute GVHD, which generally occurs within 3 months following BMT, include maculopapular exanthema and perifollicular papular lesions. Psoriasiform skin eruption as a manifestation of acute GVHD is rare. We report the case of a 4-year-old boy who developed a generalized psoriasiform eruption shortly after undergoing an allogeneic BMT. Histologic features of both psoriasis and acute GVHD were present.

Comparison between taxane-based chemotherapy with conventional surgery-based therapy for cutaneous angiosarcoma: a single-center experience

OBJECTIVE

To show the efficacy of taxane-based chemotherapy for the treatment of cutaneous angiosarcoma.

METHODS

A case-control study comparing patients who received taxanes without wide local excision (group A, n = 5) and patients who received conventional surgery-based therapy (group B, n = 8) in one university hospital in eastern Japan. Data were collected from a total of 13 patients with cutaneous angiosarcoma treated from November 1997 through July 2009.

RESULTS

Group A received taxanes: four patients received docetaxel, and one patient received paclitaxel. Radiation was used concomitantly in two patients. Marginal local excision was performed in two patients. Group B received wide local excision followed by radiation (six patients), docetaxel (three patients), and interleukin-2 (two patients). No patients in group A had local recurrence, whereas five out of the eight patients in group B did (p < 0.05, chi-square test). Median overall survival was 31 months in group A and 10 months in group B. Estimated overall survival using the Kaplan-Meier method was significantly longer in group A (p < 0.05, log-rank test).

CONCLUSION

In our series, taxane-based chemotherapy was superior to conventional surgery-based therapy. Our results indicated that taxane regimens without mutilating surgery offered both local control and prevention of metastasis, which led to prolonged survival.

The POU domain transcription factors Oct-6 and Oct-11 negatively regulate loricrin gene expression in keratinocytes: association with AP-1 and Sp1/Sp3

Loricrin is a major component of the epidermal cornified cell envelope, and is expressed only in terminally differentiated keratinocytes. This cell differentiation-specific expression pattern suggests specific regulatory mechanisms for activation and suppression of loricrin gene transcription in differentiated keratinocytes. Here, we identified a regulatory element in the proximal promoter region of the loricrin gene involved in suppression of its expression in keratinocytes. A database search indicated that this sequence contained a POU transcription factor binding motif. Electrophoretic mobility shift assay revealed that Oct-1, Oct-6, and Oct-11 actually bind to the motif. Constructs with point mutations in the POU-binding motif showed increased reporter activity, indicating that the POU factors negatively regulate loricrin gene transcription. Cotransfection experiments suggested that Oct-6 and Oct-11 suppress loricrin gene transcription in a cooperative manner with AP-1 and Sp1. Furthermore, in vitro experiments indicated that the Oct-6 and Oct-11 can physically associate with both AP-1 factors and Sp1/Sp3. These findings indicate that Oct-6 and Oct-11 contribute to the regulation of loricrin gene transcription via interaction with AP-1 factors and Sp1/Sp3.

Malignant blue nevus arising in a giant congenital cellular blue nevus in an infant

Giant congenital blue nevus (GCBN) is rare and usually occurs on the scalp. Malignant blue nevus (MBN) is also rare and has a poor prognosis. We report a case of MBN arising in a GCBN on the back. There have been three previous reports of MBN associated with GCBN on the trunk; our case had the earliest onset of MBN arising in a GCBN.

Angiosarcoma of the scalp diagnosed by the presence of neck inflammation: a case report

Angiosarcoma is an uncommon malignancy, which spread out from the endothelial cells of vessels. Scalp angiosarcoma with cervical lymph node metastasis is particularly rare. This article describes a rare case of angiosarcoma of the scalp, presenting as neck inflammation. Imaging procedures such as computed tomography (CT), magnetic resonance image (MRI) and ultrasonography (US) were not sufficient to diagnose this case. A needle biopsy provided an effective and accurate diagnosis of cervical lymph node metastasis. Additional observation and physical examination was required to diagnose the origin of the primary cancerous lesion. Once the angiosarcoma diagnosis was confirmed histologically, sequential weekly and monthly docetaxel (DTX) treatment was effective in preventing reoccurrence. Nonetheless, the optimization of angiosarcoma treatment remains a future goal. Although patients generally describe pain and swelling at the primary lesion site, this patient complained only of painful neck inflammation, without any indication of pain or swelling of the scalp. A revised diagnostic protocol should note that cervical lymph node metastasis of unknown primary origin may result from angiosarcoma of the scalp.

Indolent subcutaneous panniculitis-like T cell lymphoma in a 1-year-old child

Subcutaneous panniculitis-like T-cell lymphoma is an uncommon form of CD8-positive cytotoxic T-cell lymphoma of the skin that predominantly affects the subcutaneous tissue and is extremely rare in early childhood (<3 yrs). Here, we present an early pediatric case with an indolent form of subcutaneous panniculitis-like T-cell lymphoma occurring at 12 months old. The subcutaneous nodules gradually disappeared spontaneously, and the girl showed excellent prognosis with no aggressive treatment.

Indocyanine green fluorescence-navigated sentinel node biopsy showed higher sensitivity than the radioisotope or blue dye method, which may help to reduce false-negative cases in skin cancer

BACKGROUND AND OBJECTIVES

Although sentinel lymph node (SLN) biopsy using radioisotope (RI) and blue dye (BD) achieved a high detection rate, approximately 5% of melanomas with negative SLNs develop nodal metastasis. We tested a new lymphatic navigation method using indocyanine green fluorescence imaging (ICG-FI) to detect such "occult" SLNs.

METHODS

Thirty-four skin cancer patients received SLN biopsy with the following three methods: RI (99Tc-tin colloid), BD (2% patent blue), and ICG (0.5% indocyanine green). Lymph nodes detected by any of the three methods were counted as SLNs.

RESULTS

ICG-FI detected more SLNs in 8 out of the 34 cases (24%). The average numbers of SLNs detected by ICG-FI, RI, and BD were 2.18, 1.76, and 1.73, respectively. Interestingly, ICG-FI not only detected more SLNs in one basin (ICG-FI: 1.64, RI: 1.50, and BD: 1.51 SLNs per basin), but also detected additional SLNs in other basins (ICG-FI: 1.32, RI: 1.18, and BD: 1.15 basins per case).

CONCLUSION

ICG-FI detected SLNs more efficiently than did the conventional methods, and these "occult" SLNs may offer an explanation for some false-negative cases. We recommend using ICG-FI in addition to a conventional method to reduce the risk of overlooking these "occult" SLNs.

Carbenoxolone alters the morphology of adipose tissues and downregulates genes involved in adipogenesis, glucose transport and lipid metabolism in high-fat diet-fed mice

Glucocorticoid (GC) excess promotes adipose tissue accumulation, and 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) plays an important role in the local amplification of GC. Therefore, in this study, we investigated the effects of carbenoxolone (CBX), an 11β-HSD1 inhibitor, on morphological changes in visceral fat, and the expression of genes involved in adipogenesis and lipid metabolism in high-fat (HF) diet-fed mice. Mice were fed a HF diet from 5 weeks of age. At 10 weeks of age, the mice received an intraperitoneal injection of CBX or vehicle every day for 2 weeks. CBX decreased body weight and visceral fat mass, and improved insulin sensitivity in HF-fed mice. This was accompanied by reduced adipocyte size and a decrease in large-sized adipocytes in visceral fat. The expression of adipogenesis (PPARγ and C/EBPα), glucose transport (GLUT4) and lipid metabolism (LPL, ATGL, and HSL)-related genes were suppressed in CBX mice. CBX treatment induced beneficial morphological changes in visceral fat and decreased the expression of adipogenesis, glucose transport and lipid metabolism-related genes. These findings reveal a potential mechanism underling the effects of CBX on reduced fat accumulation and improved insulin sensitivity.

Altered gene expressions of ghrelin, PYY, and CCK in the gastrointestinal tract of the hyperphagic intrauterine growth restriction rat offspring

Intrauterine growth restriction (IUGR) is associated with a substantially greater incidence of metabolic syndrome in adulthood. Animal studies have shown that IUGR offspring are hyperphagic during the early postnatal period and therefore exhibit obesity. The molecular mechanisms underlying food intake regulation in the gastrointestinal tract have not been clarified in IUGR. In the present study, we utilized a rat model of IUGR by restricting the food intake of the mother (50% of the normal intake, ad libitum; FR group) from day 7 of gestation until delivery. Pups from undernourished mothers were fostered by control mothers. We examined the food intake and assessed the gene expressions of ghrelin, peptide YY (PYY), and cholecystokinin (CCK) in the alimentary tract of male newborns (postnatal day1) and adult offspring (age, 7 months). Compared to the offspring whose mothers received the standard diet ad libitum (CON offspring), FR offspring were hyperphagic from the weaning time until the end of the experiment, and resulted in a heavier final weight. Both newborn and adult FR offspring had higher ghrelin gene expression in the stomach and higher ghrelin plasma levels than did the controls. Although the gastrointestinal gene expressions and plasma levels of the anorexic peptides, PYY and CCK, were elevated in the FR newborns, they decreased in the FR adults. Our findings suggest that the altered gene expressions of orexigenic and anorexigenic gut peptides in the gastrointestinal tract in the maternal undernutrition-induced IUGR offspring provide a potential mechanism to explain hyperphagia and obesity seen in these offspring.

Linear childhood discoid lupus erythematosus following the lines of Blaschko: successfully treated with topical tacrolimus

The linear arrangement of discoid lupus erythematosus is uncommon. Here, we report a 6-year-old Japanese girl with linear discoid lupus erythematosus following the lines of Blaschko on her face and neck. Topical tacrolimus treatment improved the eruptions. The present case also indicated the important role of epidermal and dermal cells as well as immune cells in the pathogenesis of cutaneous lupus erythematodes.

Enforced ROR(gamma)t expression in haematopoietic stem cells increases regulatory T cell number, which reduces immunoreactivity and attenuates hypersensitivity in vivo

BACKGROUND

The retinoic acid receptor-related orphan receptor gammat (ROR(gamma)t) is a key transcription factor involved in the generation of T-helper 17 (Th17) cells, which mediate tissue inflammation and autoimmunity. However, recent studies indicated that less than half of all ROR(gamma)t(+) Talphabeta cells express IL-17, while the others are Foxp3(+) Talphabeta cells expressing IL-10. These observations raise questions regarding the role of ROR(gamma)t in the early differentiation process of T cells from haematopoietic stem cells.

METHODS

To examine the role of RORyt in T cell differentiation, mice were reconstituted with ROR(gamma)t cDNA-transduced haematopoietic stem cells and the role of ROR(gamma)t in T cell differentiation was studied in a mouse bone marrow transplantation model in vivo.

RESULTS

While the number of Th17 cells increased with the reduction in Thl cell number in transplanted mice, peripheral blood Foxp3(+) Talphabeta cell number also increased, which attenuated the severity of contact hypersensitivity on skin exposed to 2,4-dinitrofluorobenzene. The number of non-transduced Foxp3(+) regulatory T cells (Treg cells) also increased in these mice.

CONCLUSION

These observations suggest that the enforced expression of ROR(gamma)t in haematopoietic stem cells induces differentiation of Thl7 cells and results in an increase in Foxp3(+) Treg cell number to limit self-tissue damage.

Effects of maternal high-fat diet on serum lipid concentration and expression of peroxisomal proliferator-activated receptors in the early life of rat offspring

Peroxisomal proliferator-activated receptors (PPARs) play an important role in the regulation of lipid metabolism. The aim of this study was to investigate the effects of a maternal high-fat (HF) diet on serum lipid concentration and PPAR gene expression in liver and adipose tissue in the early life of the rat offspring. Female Sprague-Dawley rats were fed either an HF or control (CON) diet 6 weeks before mating and throughout gestation and lactation. Blood and tissue samplings of male offspring were carried out at birth or weaning. Birth weights were similar and serum triglyceride (TG) and nonesterified fatty acid (NEFA) levels showed no significant difference between HF and CON newborns, despite greatly increased hepatic PPARα mRNA expression in the HF newborns (p<0.05). Both HF newborns and weanlings revealed significantly decreased hepatic PPARγ expression compared with controls (p<0.0001). Hepatic PPARα expression in the HF weanlings was reduced markedly compared with CON weanlings (p<0.0001) and showed a negative correlation with serum TG levels (r=-0.743, p<0.05). However, epididymal expression of PPARγ in the HF weanlings was upregulated significantly compared with controls (p<0.05) and demonstrated a positive correlation with epididymal fat mass (r=0.733, p<0.05). These were accompanied by obesity as well as a rise in serum TG by 79% (p<0.05) and NEFA concentration by 36% (p<0.05) in these HF weanlings. Our findings suggest that maternal HF diet leads to alterations in PPAR gene expression in the weanling offspring, which is associated with the disturbed lipid homeostasis.

Overexpression of the transcription factor Yin-Yang-1 suppresses differentiation of HaCaT cells in three-dimensional cell culture

Yin-Yang-1 (YY1) is a member of the GLI-Krüppel family of transcription factors, and both YY1 mRNA and protein expression have been identified in a number of different tissues and cell types suggesting that it is expressed both constitutively and ubiquitously. In epidermal tissue, however, we reported previously that YY1 protein is expressed at high levels in undifferentiated basal keratinocytes and is downregulated during differentiation toward the suprabasal layers. This differential expression pattern during keratinocyte differentiation suggests that YY1 may have an important role in regulating keratinocyte differentiation. In this study, we examined the role of YY1 in differentiation of the human keratinocyte cell line HaCaT using air-liquid interface three-dimensional culture. The constitutive overexpression of YY1 in HaCaT cells during air exposure-induced differentiation resulted in an undifferentiated phenotype, thickening of the stratified layers, suppression of differentiation marker expression, and retention of proliferative activity. These findings suggested that YY1 may have an important role in maintenance of the undifferentiated phenotype of keratinocytes in the basal epidermal layer, and that reduction of YY1 expression in the suprabasal layers may allow keratinocytes to differentiate and move toward the upper layers of the epidermis.

Trabecular and cortical bone separately assessed at radius with a new ultrasound device, in a young adult population with various physical activities

The aim was to evaluate a new ultrasound device in a young adult population and to assess its reproducibility via comparison to DXA measurements and geometrical measurements from high-resolution radiographs. Ninety-three subjects aged between 20 and 51 years were recruited and divided into four groups according to their gender and physical activity status: 22 male athletes, 19 male controls, 21 female athletes, and 31 female controls. Ultrasonic measurements were assessed by the prototype LD-100 (Oyo Electric Co., Kyoto, Japan) on the dominant distal radius. Attenuation in the radius (dB), cortical bone thickness (mm), radius thickness (mm), mass density of cancellous bone (mg/cm(3)), and elasticity (GPa) of cancellous bone were obtained. BMD was measured by DXA at the dominant distal radius. Radius images were obtained with a direct high-resolution digital X-ray device (BMA, D(3)A Medical Systems), and radius and cortical thicknesses were estimated using a specific software (ImageJ, Bethesda, USA), in an area site-matched with LD-100. There was a significant positive correlation between site-matched BMD measurement and LD-100 parameters (p<0.004), X-ray radius thickness, and LD-100 parameters except elasticity (p<0.05, r>0.32), X-ray cortical thickness and LD-100 attenuation and cortical thickness (p<0.01). A significantly higher attenuation, cortical and radius thicknesses were found in athletes compared to controls (p<0.05). The radius thickness measured on radiographs was significantly higher in athletes versus controls in both sexes, and cortical thickness was significantly higher in male athletes versus controls. These data suggest a positive influence of physical activity on bone cortical measurements. This study also confirmed the particular interest of bone assessment by ultrasound.

Aortocaval fistula after endovascular stent-grafting of abdominal aortic aneurysm

The authors present a case report of a 79-year-old man with insufficient cardiac contractile function who underwent endovascular stent-grafting for an abdominal aortic aneurysm. Thirty months later, the aneurysm ruptured into the inferior vena cava and subsequently formed an aortocaval fistula caused by migration of the stent-graft. Urgent secondary endovascular stent-grafting successfully excluded the blood flow into the vena cava. Endovascular stent-grafting is deemed suitable for treating this serious disorder, especially in severely debilitated or compromised patients who might not withstand a standard surgical intervention. Furthermore, in patients with previous stent-grafting, since the primary stent-graft makes repair by open surgery more difficult, a secondary endovascular intervention is recommended if feasible.