Kiyoko Nashiro

Differential expression of connective tissue growth factor gene in cutaneous fibrohistiocytic and vascular tumors

Connective tissue growth factor (CTGF) is a member of a family of immediate early gene products that may play an important role during tissue regeneration, wound repair and skin fibrosis. In this study, CTGF gene expression in mesenchymal tumors was investigated by in situ hybridization and CD34 antigen expression was studied by means of immunohistochemical staining. CTGF mRNA was expressed in fibroblasts of all nine dermatofibromas examined, but five of seven dermatofibrosarcoma protuberans (DFSP) or two cases of malignant fibrous histiocytoma were negative for its expression. In contrast, CD34 antigen was expressed only in DFSP. In vascular tumors, CTGF mRNA was expressed in pyogenic granuloma but not in angiosarcoma. In addition, the endothelial cells in angiolipoma and angioleiomyoma, but not in venous lake, expressed CTGF mRNA. These vascular lesions were all positive for CD34 expression. Tumors of other origins were negative for CTGF mRNA. Our findings indicated that benign fibroblasts and/or vascular endothelial cells have the capability to express CTGF mRNA when activated, but these cells lose this ability when they achieve malignant potency. Thus, examination of CTGF gene expression may be useful for differentiating between benign and malignant mesenchymal tumors, or to determine the origin of the tumors in connective tissue.

Prolactin enhances basal and IL-17-induced CCL20 production by human keratinocytes.

Psoriasis vulgaris is an autoimmune dermatosis with Th17 infiltration. Prolactin (PRL) may participate in the pathogenesis of psoriasis. The chemokine CCL20 recruits Th17 cells, and CCL20 production by epidermal keratinocytes is enhanced in psoriatic lesions. We examined the in vitro effects of PRL on CCL20 production in human keratinocytes. PRL increased basal and IL‐17‐induced CCL20 secretion, and mRNA expression in keratinocytes. CCL20 production by PRL was suppressed by antisense oligonucleotides against the AP‐1 components c‐Fos and c‐Jun, whereas that by IL‐17 was suppressed by antisense NF‐κB p50 and p65. CCL20 production induced by PRL plus IL‐17 was suppressed by antisense c‐Fos, c‐Jun, p50, and p65. PRL alone increased the transcriptional activity of AP‐1, and c‐Fos and c‐Jun expression; moderately enhanced NF‐κB activity and IκBα phosphorylation; and potently increased IL‐17‐induced NF‐κB activity. MEK and JNK inhibitors suppressed PRL‐ or PRL‐plus‐IL‐17‐induced CCL20 production and AP‐1 activities. MEK inhibitor suppressed PRL‐induced c‐Fos expression, whereas JNK inhibitor suppressed c‐Jun expression. PRL induced ERK and JNK phosphorylation. These results suggest that PRL may enhance basal and IL‐17‐induced CCL20 production in keratinocytes by AP‐1 and NF‐κB activation, which is partially mediated via MEK/ERK and JNK. PRL may promote Th17 infiltration into psoriatic lesions via CCL20.

Expression of tetra‐spans transmembrane family (CD9, CD37, CD53, CD63, CD81 and CD82) in normal and neoplastic human keratinocytes: an association of CD9 with α3β1 integrin

Tetra‐spans transmembrane family (TSTF) members (CD9, CD37, CD53, CD63, CD81 and CD82) have potent effects on cell growth, motility and adhesion in various cells. However, little is known about their expression in human skin. Using immunohistological techniques, we have studied the localization of all six members of TSTF in normal and carcinomatous human keratinocytes. CD9, CD81 and CD82 were expressed in the entire living layers of the epidermis. Their staining pattern was quite similar, and was mainly intercellular with occasional intracellular immunoreactivity. CD53 expression was confined to the intercellular spaces of the upper spinous or granular layer in the normal epidermis. No clear‐cut expression of CD63 could be detected in the epidermis. CD37 was not detected at all. Cultured human keratinocytes also expressed CD9, CD81 and CD82 at the surface membrane of cell‐cell boundaries. Expression of CD37 and CD53 was negative in cultured keratinocyte, while CD63 was clearly localized in the cytoplasmic lysosomes. An immunoprecipitation assay revealed that α3β1 integrin is molecularly associated with CD9. The expression of CD9, CD81 and CD82 was markedly down‐regulated in basal cell carcinoma but not in Bowens disease. The abundant and differential expression of TSTF molecules and the selective association of CD9 with α3β1 integrin suggest that the TSTF molecules may be involved in the regulation of epidermal differentiation and integrity in vivo.

Dysregulated expression of transforming growth factor β and its type-I and type-II receptors in basal-cell carcinoma

In mammals, transforming growth factor‐β (TGF‐β) is found in 3 highly homologous isoforms that exert their effects via heteromeric complexes of type‐I and type‐II receptors (TβR‐I and TβR‐II). TGF‐β regulates the growth and metabolism of various cell types, including keratinocytes. We have investigated the immunohistological localization of TGF‐β1, TGF‐β2, TβR‐I and TβR‐II in normal human skin, basal‐cell carcinoma (BCC), Bowens disease, seborrheic keratosis, eccrine poroma and eccrine spiradenoma using frozen tissue specimens. In normal human skin, the immunoreactive TGF‐β2, but not TGF‐β1, was detected predominantly in the epidermis, follicles and sebaceous glands. The epidermal expression of TβR‐I and TβR‐II was very weak in the majority of normal skins. In BCC, TGF‐β2 expression was markedly reduced or completely negative. In addition, TβR‐I‐ and TβR‐II‐positive stromal cells were accumulated in the fibrotic stroma in some BCCs. These stromal cells were partly but moderately positive for TGF‐β1. Decreased expression of TGF‐β2 was likely to be associated with the differentiation state of BCC cells, since TGF‐β2 expression was clearly observed in the squamoid foci of BCC. In addition, no expression of TGF‐β2 was detected in the eccrine secretory portion or in eccrine spiradenoma, but it was detected in the upper eccrine ducts and in eccrine poroma. Int. J. Cancer 71:505‐509, 1997.

Expression of tetraspans transmembrane family in the epithelium of the gastrointestinal tract

Tetraspans transmembrane family (TSTF) members, also known as tetraspanin superfamily, have various effects on cell proliferation, motility, and adhesion not only in hematopoietic cells, but also in other type of cells. However, little is known about their expression in the human gastrointestinal (GI) tract. The authors characterized immunohistologically the localization of six members of TSTF (CD9, CD37, CD53, CD63, CD81, and CD82) in the normal epithelium from esophagus to colon. CD9 and CD82 molecules were strongly expressed in all epithelial surface membranes, from esophagus to colon, and their staining pattern was quite similar. Expression of CD37 was not detectable throughout the GI tract. Expression of CD53 was barely detectable. Expression of CD63 was clearly detected distal to the stomach, including the duodenum, small intestine, and colon. On the contrary, expression of CD81 was detected only in the esophagus--confined to a few layers from the basal layer. From these data it seems likely that the expression of TSTF molecules might be regulated differentially depending on the site of the GI tract.

Lichen planus pemphigoides: Case report and results of immunofluorescence and immunoelectron microscopic study

A Japanese woman with lichen planus pemphigoides is reported. Immunologic characteristics of lichen planus pemphigoides antigen in the patient were investigated by indirect immunofluorescence and compared with those of bullous pemphigoid antigen or epidermolysis bullosa acquisita antigen. Ultrastructural localization of lichen planus pemphigoides antigen was studied with the use of immunoelectron microscopic techniques. Lichen planus pemphigoides antigen showed localization similar to that of bullous pemphigoid antigen but different from that of epidermolysis bullosa acquisita antigen. The antigenic stability of lichen planus pemphigoides antigen was different from that of bullous pemphigoid antigen or epidermolysis bullosa acquisita antigen. Thus this study demonstrates that lichen planus pemphigoides antigen is different from bullous pemphigoid antigen.

Administration of IgG Fraction of Epidermolysis Bullosa Acquisita (EBA) Serum into Mice

In order to study the pathogenic role of autoantibodies in the serum of EBA patients, we tried to induce EBA lesions in mice by administration of the IgG fraction of EBA serum via the intraperitoneal (i.p.) or subcutaneous (s.c.) routes into neonatal or adult mice. We also tried to induce EBA lesions in fetuses by intravenous (i.v.) injection of EBA serum into pregnant mice.

Bilateral Periorbital Eccrine Hidrocystoma

We saw four patients showing identical features as cystic lesions on the bilateral external canthi. Histological examination showed cystic cavities in the dermis. Histological and enzyme histochemical findings suggest that these cystic tumors are of eccrine origin. Thus we diagnosed these cytic tumors as eccrine hidrocystoma with characteristic clinical feature. The recognition of this feature would help to correctly diagnose these eccrine hidrocystoma.

Efficient Generation of Functional Pancreatic β Cells from Human iPS Cells.

Insulin‐secreting cells have been generated from human embryonic or induced pluripotent stem cells (iPSCs) by mimicking developmental processes. However, these cells do not always secrete glucose‐responsive insulin, one of the most important characteristics of pancreatic β‐cells. We focused on the importance of endodermal differentiation from human iPSCs in order to obtain functional pancreatic β‐cells.

Efficient generation of functional pancreatic β-cells from human induced pluripotent stem cells.

Insulin‐secreting cells have been generated from human embryonic or induced pluripotent stem cells (iPSCs) by mimicking developmental processes. However, these cells do not always secrete glucose‐responsive insulin, one of the most important characteristics of pancreatic β‐cells. We focused on the importance of endodermal differentiation from human iPSCs in order to obtain functional pancreatic β‐cells.