Norihisa Matsuyoshi

Neutrophils from MMP‐9‐ or neutrophil elastase‐deficient mice show no defect in transendothelial migration under flow in vitro

Recent evidence has suggested a role for neutrophil proteases during certain inflammatory responses. We demonstrated previously that neutrophil proteases can degrade components of the adherens junctions during neutrophil‐endothelial adhesion. We tested the hypothesis that degradation of VE‐cadherin at lateral junctions by elastase or MMP‐9 facilitates neutrophil transendothelial migration. Neutrophils from MMP‐9 or elastase null mice and strain‐matched control mice expressed high levels of LFA‐1, Mac‐1, and L‐selectin on their cell surface. Under flow conditions, wild‐type and deficient neutrophils rolled, arrested, and transmigrated activated murine endothelium. There was no difference in the total numbers of interacting neutrophils or in the percentage of transmigrated cells. In addition, deficient neutrophils remained capable of degrading murine endothelial VE‐cadherin. These results indicate that although neutrophil proteases may play a role in the acute inflammatory response, neutrophil elastase or MMP‐9 is not essential for neutrophil transendothelial migration in this murine system.

Immunohistochemical evaluation of E-cadherin adhesion molecule expression in human gastric cancer.

E-cadherin (ECD) is one of subclasses of the cadherin family which plays a major role in the maintenance of intercellular adhesion in epithelial tissues. An immunohistochemical study of ECD expression was performed on gastric adenocarcinoma from 103 patients using our monoclonal antibody for human ECD (HECD-1). ECD was strongly expressed in normal gastric epithelium without exception; however, various staining patterns were observed in cancer tissues. The frequency of tumours with preserved ECD expression (Pre-type) and reduced ECD expression (Rd-type) was 42% and 58% respectively. Tumours with a high frequency of Rd-type expression particularly included: undifferentiated tumours (85%, 46/54), Borrmanns type 4 (90%, 9/10), tumours larger than 2.6 cm in diameter (65%, 53/81), tumours invading beyond the subserosa layer (78%, 46/59), and tumours with infiltrative growth (87%, 41/47). Furthermore, the frequency of Rd-type expression in cases with peritoneal dissemination (82%, 9/11) or lymph node metastasis (73%, 43/59) was significantly higher than that in cases without dissemination or metastasis. These results suggest that ECD might play a key role in the genesis of histological differentiation, and that the reduction of ECD expression may affect the mode of invasion and metastasis of human gastric cancer cells.

Roles of E- and P-cadherin in the human skin.

The Ca2+‐dependent cell‐cell adhesion molecules, termed cadherins, are subdivided into several subclasses. E (epithelial)‐ and P (placental)‐cadherins are involved in the selective adhesion of epidermal cells.

Loss of T-cadherin (CDH13, H-cadherin) expression in cutaneous squamous cell carcinoma.

We previously reported that T-cadherin (CDH13, H-cadherin), a unique cadherin molecule, was expressed on the basal cell layer in normal murine and human epidermis. In the present study, T-cadherin expression in archival human skin specimens comprising a spectrum of human squamous cell neoplasia was investigated. T-cadherin expression was observed in both normal epidermal basal cells and adnexal epithelial cells of formalin-fixed and paraffin-embedded tissue sections. Western immunoblotting also revealed that mature T-cadherin protein was expressed in cultured human skin tissue equivalent. Atypical keratinocytes in 27 of 53 specimens of actinic keratosis and 23 of 30 specimens of Bowen’s disease expressed T-cadherin. In contrast, T-cadherin was focally expressed in 6 of 56 invasive cutaneous squamous cell carcinomas. To explore the molecular mechanism of down-regulation of T-cadherin expression in invasive squamous cell carcinoma, loss of heterozygosity, genetic alternations, and methylation status in the 5′ region of the T-cadherin gene were investigated. Loss of heterozygosity at intron 1 of the T-cadherin gene was observed in 8 of 28 informative cases of invasive squamous cell carcinoma. Although no structural genomic alternations were found by sequence analysis, aberrant promoter methylation of the T-cadherin gene was found in 12 of 28 invasive squamous cell carcinomas. T-cadherin expression was restored in cultured A431 cells, in which aberrant methylation was found by treatment with the demethylating agent 5′-aza-2-deoxycytidine. These findings suggest that a combination of deletion and aberrant methylation of the T-cadherin gene may play a role in loss of gene expression in a considerable number of invasive cutaneous squamous cell carcinomas.

Cadherins in Cutaneous Biology

The role of cadherins in cutaneous biology has focused mainly on the classical cadherins, E‐ and P‐cadherin. In this review, roles for cadherins in skin morphogenesis, keratinocyte differentiation, and cancer metastasis are discussed.

The expression of nectin‐1α in normal human skin and various skin tumours

Summary Backgroundu2003A novel cell–cell adhesion system that consists of nectin and afadin has been identified at cadherin‐based cell–cell adherens junctions. Nectin is a Ca2+‐independent homophilic and heterophilic cell adhesion molecule that belongs to the immunoglobulin superfamily. Nectin has recently been shown to serve as an α‐herpesvirus entry and cell–cell spread mediator. In spite of the ubiquitous expression of nectin‐1α, its detailed localization in human skin has not been examined so far.

Soluble E-cadherin : a novel cutaneous disease marker

E‐cadherin is a major homophilic cell‐cell adhesion molecule of the skin. There are two forms of E‐cadherin—membrane and soluble types. Although various abnormalities of the former type have been identified in some cutaneous diseases, information relating to the latter is sparse. We measured the concentrations of soluble E‐cadherin in several cutaneous diseases, and found higher levels in sera from patients with bullous pemphigoid, pemphigus vulgaris, psoriasis vulgaris and inflammatory skin diseases, compared with controls. In psoriasis vulgaris the levels of soluble E‐cadherin in sera correlated with the PASI score. In normal individuals, levels in suction blister fluid were double those in sera. These findings suggest that changes occur in circulating levels of soluble E‐cadherin in skin disease, possibly reflecting increased turnover and/or proteolysis of cell‐surface molecules in the epidermis.

Keratin 9 point mutation in the pedigree of epidermolytic hereditary palmoplantar keratoderma perturbs keratin intermediate filament network formation

Keratins form an intracellular keratin filament network in keratinocytes. Point mutations in the epidermal keratins could lead to the disruption of keratin filament formation, developing skin diseases such as epidermolytic hereditary palmoplantar keratoderma (EHPPK). We found a G to A transition in keratin 9 (K9) cDNA, resulting in the substitution of glutamine for arginine at 162, in all patients of a pedigree of EHPPK. Transfection into MDCK cells and DJM‐1 cells revealed that the plasmid CMX vector containing normal keratin 9 cDNA showed normal keratin network formation, whereas the vector with a G to A point mutated keratin 9 cDNA showed disrupted keratin filaments with droplet formation in the cells. These results indicate that the point mutation seen in our patients had a dominant‐negative effect on keratin network formation.

Reciprocal altered expression of T-cadherin and P-cadherin in psoriasis vulgaris

Summaryu2003 Backgroundu2003The most characteristic change in psoriasis vulgaris is markedly increased, persistent keratinocyte proliferation. The underlying mechanism of excessive epidermal growth is controversial. We previously found and reported that T‐cadherin was expressed in keratinocytes and confined to the basal layer of mouse and human skin. Invasive cutaneous squamous cell carcinoma showed a loss of T‐cadherin expression. Another study showed that T‐cadherin was a negative growth regulator of epidermal growth factor in T‐cadherin transfectant neuroblastoma cells.

An acquired bullous dermatosis due to an autoimmune reaction against uncein

Summary A 59‐year‐old male showed acquired. mechanically induced, scarring blisters on the fingers, toes, scalp and abdomen, as well as in the oral cavity. Ultrastructural and immunohistochemical examination of the bullae revealed junctional epidermal‐dermal separation and lgG deposits in the lamina lucida of the basement membrane zone (BMZ). where the reactivity of the 19‐DKJ‐1 monoclonal antibody was decreased. Anti‐BMZ autoantibodies detected in his serum were reactive to the lower lamina lacida region of normal human skin. SDS‐PAGE of affinity purified antigens from human keratinocytes with IgG from the patients serum revealed three polypeptide bands at 165, 135 and 1OO kDa. in reduced condition. The indirect immunofluorescence test of his serum was negative on skin cryosections from patients with lethal junctional epidermolysis bullosa. Pretreatment of normal human skin sections with the patients serum, blocked the binding of 19‐DEJ‐1 monoclonal antibody but not that of the GB3 monoclonal antibody. This case is considered to be an acquired autoimmune bullous dermatosis due to an autoantibody reaction against uncein (19‐DEJ‐1 antigen). a component of anchoring filaments.