Immunohistochemical expression of ezrin in cutaneous basal and squamous cell carcinomas

Ezrin is a member of the ezrin-radixin-moesin family of proteins, which link the actin-containing cytoskeleton to the plasma membrane. Overexpression of ezrin protein is correlated with the metastatic potential in several cancers. Little is known about the distribution of ezrin in normal epidermis and nonmelanoma skin cancer; therefore, in the current study, we examined the immunohistochemical expression of ezrin in normal skin (10 biopsies) and epithelial skin tumors (25 basal cell carcinoma [BCC] and 20 squamous cell carcinoma [SCC]). Ezrin was expressed in epidermis of all normal controls with a prominent membranous pattern compared with 93.3% positivity in malignant cases with a significant higher intensity (assessed by H score) in favor of the latter (P = .002). Cytoplasmic expression of ezrin either alone or associated with membranous expression was both seen in BCC and SCC. The median value of H score in SCC (160) cases was higher than that in BCC (60). H score values of ezrin expression in BCC was significantly higher in tumors arising in sites other than the head and neck (P = .04). In SCC, the intensity of ezrin expression tended to be associated with advanced stage (P = .08). Our study demonstrated the probable tumorigenic role of ezrin in epithelial skin tumor formation. It may enhance local invasion or metastasis of epithelial skin tumors, which necessitates further larger study to clarify. The intensity rather than the pattern of ezrin expression had a more probable impact on the tumor behavior.     

Interactions between the L1 cell adhesion molecule and ezrin support traction-force generation and can be regulated by tyrosine phosphorylation

An Ig superfamily cell-adhesion molecule, L1, forms an adhesion complex at the cell membrane containing both signaling molecules and cytoskeletal proteins. This complex mediates the transduction of extracellular signals and generates actin-mediated traction forces, both of which support axon outgrowth. The L1 cytoplasmic region binds ezrin, an adapter protein that interacts with the actin cytoskeleton. In this study, we analyzed L1-ezrin interactions in detail, assessed their role in generating traction forces by L1, and identified potential regulatory mechanisms controlling ezrin-L1 interactions. The FERM domain of ezrin binds to the juxtamembrane region of L1, demonstrated by yeast two-hybrid interaction traps and protein binding analyses in vitro. A lysine-to-leucine substitution in this domain of L1 (K1147L) shows reduced binding to the ezrin FERM domain. Additionally, in ND7 cells, the K1147L mutation inhibits retrograde movement of L1 on the cell surface that has been linked to the generation of the traction forces necessary for axon growth. A membrane-permeable peptide consisting of the juxtamembrane region of L1 that can disrupt endogenous L1-ezrin interactions inhibits neurite extension of cerebellar cells on L1 substrates. Moreover, the L1-ezrin interactions can be modulated by tyrosine phosphorylation of the L1 cytoplasmic region, namely, Y1151, possibly through Src-family kinases. Replacement of this tyrosine together with Y1176 with either aspartate or phenylalanine changes ezrin binding and alters colocalization with ezrin in ND7 cells. Collectively, these data suggest that L1-ezrin interactions mediated by the L1 juxtamembrane region are involved in traction-force generation and can be regulated by the phosphorylation of L1.     

ERM/ETV5 and RUNX1/AML1 expression in endometrioid adenocarcinomas of endometrium and association with neoplastic progression

The majority of endometrioid endometrial carcinomas (EEC) is diagnosed at stage I. Among these, 30% present myometrial invasion (stage IB), which is associated with tumor spread and relapse after primary treatment. Although an increased expression of RUNX1/AML1 and ERM/ETV5 in EEC have been suggested to be associated with early events of myometrial infiltration, there is no data regarding its expression along the evolution of EEC and possible associations with other clinicopathological parameters. Therefore, ERM/ETV5 and RUNX1/AML1 protein and gene expression profiles were assessed in different EEC stages to evaluate their role in endometrial carcinogenesis. RUNX1/AML1 and ERM/ETV5 proteins were analyzed by immunohistochemistry in 219 formalin fixed paraffin embedded endometrioid tumors and in 12 normal atrophic and proliferative endometrium samples. RUNX1/AML1 and ERM/ETV5 genes expression were analyzed by RT-qPCR. RUNX1/AML1 and ERM/ETV5 expression were decreased with increasing EEC stage, with a positive correlation between protein and gene expression for ERM/ETV5, but not for RUNX1/AML1. Both proteins were present in the nucleus of the tumor cells, whereas RUNX1/AML1, but not ERM/ETV5, was expressed in 7 out of 12 normal endometrial samples, with its expression being restricted to the cytoplasm of the positive cells. We concluded that there is a higher expression of ERM/ETV5 in early stages of EEC, whereas there seems to be a RUNX1/AML1 translocation from cytoplasm to nucleus in EEC neoplastic transformation.     

Shifts in cellular localization of moesin in normal oral epithelium, oral epithelial dysplasia, verrucous carcinoma and oral squamous cell carcinoma

BACKGROUND: Moesin, a member of ERM (ezrin/radixin/moesin) family, links actin filaments of cell surface structure to the cell membrane. The purpose of the study is to assess the shifts in cellular distribution of moesin in normal oral epithelium, oral epithelial dysplasia (OED), verrucous carcinoma (VC), and oral squamous cell carcinoma (OSCC). METHODS: The expression of moesin was evaluated immunohistochemically in paraffin-embedded tissues of 59 specimens of OSCC, 35 specimens of OED, 17 specimens of VC, and five specimens of normal oral epithelium. RESULTS: In the normal oral epithelia, all specimens showed a pattern of membranous expression against the anti-moesin antibody in the basal layer cells. In the OED specimens, moesin was dominantly expressed in the cell membrane except for the cornified layer. In VC and OSCC specimens, almost the whole of the carcinoma cells were stained with anti-moesin antibody. However, in OSCC samples, moesin was markedly expressed increasingly in the cytoplasm and decreasingly in the cell membrane, as compared with OED and VC. In addition, there was a significant correlation between the pattern of moesin expression and tumor differentiation in OSCC. CONCLUSIONS: Our results suggest that it is useful to detect the moesin expression as adjunct to screening mucosal lesions in the oral cavity.     

Immunoexpression of proteins involved in cytoskeleton remodeling in benign odontogenic lesions

ObjectiveThe present study was designed to analyze the immunolocalization of proteins involved in cytoskeleton remodeling, such as moesin and Rho-A, in benign odontogenic lesions that present with expansive growth and invasive clinical behavior.Materials and methodsExpressions of moesin and Rho-A in odontogenic epithelium were evaluated by immunohistochemical analysis in 45 odontogenic lesions using monoclonal antibodies.ResultsOur results demonstrated strong membranous and cytoplasmic expressions of moesin in the epithelial cells in 66.7% and 44.4% of the odontogenic lesions, respectively. Furthermore, Rho-A expression in odontogenic epithelium was strong in the membrane and cytoplasm of 51.1% and 62.2% of the odontogenic lesions, respectively. A statistically significant correlation was found between the membranous and cytoplasmic expressions of moesin (p = 0.000) and those of Rho-A (p = 0.048) in odontogenic epithelial cells, while no statistically significant correlation was found between moesin and Rho-A expressions (p > 0.05).ConclusionsThe present study confirmed the strong expressions of moesin and Rho-A by odontogenic epithelial cells, suggesting their involvement in the development of benign odontogenic lesions. However, this study has failed to detect the connection between the moesin and Rho-A interaction in expansive growth and local invasiveness of these lesions.     

Non-adjuvanted flagellin elicits a non-specific protective immune response in rainbow trout (Oncorhynchus mykiss, Walbaum) towards bacterial infections

Enteric redmouth disease, caused by Yersinia ruckeri, may result in high mortalities in farmed salmonids. Prophylaxis has been achieved with an immersion vaccine comprised of inactivated serovar 1 biotype 1 (motile) Y. ruckeri cultures. However, there has been a growing number of enteric redmouth outbreaks in vaccinated livestock associated with serovar 1 biotype 2 (non-motile) Y. ruckeri strains which do not produce flagellin. It was the aim of this study to evaluate the protective role of flagellin in enteric redmouth vaccines. Results showed that flagellin in the inactivated whole-cell vaccine were not the main immunoprotective molecule in eliciting a protective immune response towards infection. However, use of non-adjuvanted flagellin as a sub-unit vaccine, both in the native and recombinant form, resulted in a potent non-specific protective function towards challenge with biotype 1 (flagellin-producing) and biotype 2 (flagellin-devoid) Y. ruckeri. This vaccine can also protect rainbow trout against other microbial fish pathogens, for example Aeromonas salmonicida. Thus non-adjuvanted flagellin may have potential as a non-specific vaccine for fish towards bacterial pathogens.