Moesin Expression Research Articles

Moesin affects the plasma membrane expression and the immune checkpoint function of CD47 in human ovarian clear cell carcinoma

Among major histological subtypes of epithelial ovarian cancer, a higher incidence of ovarian clear cell carcinoma (OCCC) is observed in East Asian populations, particularly in Japan. Despite recent progress in the immune checkpoint inhibitors for a wide variety of cancer cell types, patients with OCCC exhibit considerably low response rates to these drugs. Hence, urgent efforts are needed to develop a novel immunotherapeutic approach for OCCC. CD47, a transmembrane protein, is overexpressed in almost all cancer cells and disrupts macrophage phagocytic activity in cancer cells. Ezrin-Radixin-Moesin (ERM) family member of proteins serve as scaffold proteins by crosslinking certain transmembrane proteins with the actin cytoskeleton, contributing to their plasma membrane localization. Here, we examined the role of ERM family in the plasma membrane localization and functionality of CD47 in OCCC cell lines derived from Japanese women. Confocal laser scanning microscopy analysis showed colocalization of CD47 with all three ERM in the plasma membrane of OCCC cells. RNA interference-mediated gene silencing of moesin, but not others, decreased the plasma membrane expression and immune checkpoint function of CD47, as determined by flow cytometry and in vitro phagocytosis assay using human macrophage-like cells, respectively. Interestingly, clinical database analysis indicated that moesin expression in OCCC was higher than that in other histological subtypes of ovarian cancers, and the expression of CD47 and moesin increased with the cancer stage. In conclusion, moesin is overexpressed in OCCC and may be the predominant scaffold protein responsible for CD47 plasma membrane localization and function in OCCC.

Exploring the relationship between novel MSN exon mutations and altered expression of other cytoskeleton genes in archival FFPE meningioma tissues

Meningioma, a prevalent brain tumor, can severely impact patients' health and quality of life. However, there is a scarcity of data on Ezrin/Radixin/Moesin (ERM) and the quantification of mutations in the Moesin gene. In an effort to bridge this knowledge gap, we undertook an extensive study to measure the expression of ERM genes in meningioma patients, with a concurrent assessment of mutations in the moesin gene. We analyzed the expression patterns of these genes in 50 formalin-fixed paraffin-embedded meningioma tissues, using the xylene method to deparaffinize the tissues and the TRIzol technique to isolate total RNA for qPCR expression analysis. Our results indicated that Ezrin and Radixin expression levels were significantly upregulated (p < 0.05), while Moesin expression was downregulated (p < 0.05). In addition, we analyzed Moesin exons 2–6 for mutations using sanger sequencing and identified 10 novel variants, including 5 missense, 3 synonymous, and 2 frameshift mutations. Our findings suggests that a potential role of ERM genes in meningioma pathogenesis, and our identification of MSN gene mutations may contribute to understanding their harmful or gain-of-function effects. These results offer new insights into the mechanisms underlying meningioma carcinogenesis, which may facilitate the development of targeted therapies in the future.

Functional and molecular alterations in a rat model of detrusor underactivity induced by bilateral pelvic nerve crush injury

Objective:To investigate the functional and molecular alterations in detrusor underactivity (DU) in a rat model of bilateral pelvic nerve crush injury. Methods:This study included 39 female Sprague-Dawley rats separated into three groups (sham, 2-week DU, and 4-week DU), with 13 rats in each group. A bilateral pelvic nerve crush injury was induced in each group to develop a DU model. Similarly, the sham group was identically prepared but without crushing nerves. Awake continuous cystometry was performed two weeks post-surgery in the sham and 2-week DU groups and four weeks post-surgery in the 4-week DU group (n = 7/each group). In another group of rats (n = 6/each group), the bladders were harvested for western blotting, and the expression of moesin, ezrin, and transthyretin in the bladders was evaluated. Results:On cystometry, voided volume, post-void residual urine volume, bladder capacity, and number of non-voiding contractions were significantly higher in the 2- and 4-week DU groups than in the sham group. Furthermore, voiding efficiency was significantly decreased in the 2- and 4-week DU groups compared to that in the sham group.The expression of moesin in the bladder was significantly higher in the 2-week DU group than that in the sham group. The expression of transthyretin in the bladder was significantly higher in the 2- and 4-week DU groups than that in the sham group. Conclusion:The significant increase in the expression of moesin and transthyretin in the bladder in bilateral pelvic nerve crush injuries may be related to the pathophysiology of DU.

Identification of Moesin (MSN) as a Potential Therapeutic Target for Colorectal Cancer via the β-Catenin-RUNX2 Axis.

CRC is the second leading cause of cancer-related death. The complex mechanisms of metastatic CRC limit available therapeutic choice. Thus, identifying new CRC therapeutic targets is essential. Moesin (MSN), a member of the ezrin-radixin-moesin family, connects the cell membrane to the actin-based cytoskeleton and regulates cell morphology. We investigated the role of MSN in the progression of CRC. GENT2 and oncomine were used to study MSN expression and CRC patient outcomes. MSN-specific shRNAs or MSN-overexpressed plasmid were used to establish MSN-KD and MSN overexpressed cell lines, respectively. SRB, migration, wound healing, and flow cytometry were used to test cell survival and migration. Propidium iodide and annexin V stain were used to analyze the cell cycle and apoptosis. MSN expression was found to be higher in CRC tissues than in normal tissues. Higher MSN expression is associated with poor overall survival, disease-free survival, and relapse-free survival rates in CRC patients. MSN silencing inhibits cell proliferation, adhesion, migration, and invasion in vitro, whereas MSN overexpression accelerates cell proliferation, adhesion, migration, and invasion. RNA sequencing was used to investigate differentially expressed genes, and RUNX2 was discovered as a possible downstream target for MSN. In CRC patients, RUNX2 expression was significantly correlated with MSN expression. We also found that MSN silencing decreased cytoplasmic and nuclear β-catenin levels. Additionally, pharmacological inhibition of β-catenin in MSN-overexpressed cells led to a reduction of RUNX2, and activating β-catenin signaling by inhibiting GSK3β rescued the RUNX2 downregulation in MSN-KD cells. This confirms that MSN regulates RUNX2 expression via activation of β-catenin signaling. Finally, our result further determined that RUNX2 silencing reduced the ability of MSN overexpression cells to proliferate and migrate. MSN accelerated CRC progression via the β-catenin-RUNX2 axis. As a result, MSN holds the potential to become a new target for CRC treatment.

Abstract 2774: Moesin-induced adriamycin resistance through IL-6/MSN/STAT3 axis and therapeutic efficacy of atovaquone in chemotherapy resistant triple-negative breast cancer

Abstract Introduction: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with a high frequency of chemotherapy resistance. Moesin (MSN) is a cytoskeleton linker discovered as a novel oncogene in our previous proteomics analysis. Here, we evaluated the molecular mechanisms of MSN and how it functions in response to chemotherapy, which remains unclear in TNBC. Method: The 178 in-house TNBC patient cohort and METABRIC data set were enrolled for clinicopathologic analysis. The multiple TNBC four-cell lines were used to establish MSN knock-down and over-expressed in vitro models using a lentiviral system. RNA sequencing was analyzed with MDA-MB-231 parent cell and MDA-MB-231/ADR12 (adriamycin resistance cell line). Invasion and migration assay was done. The drug response based on MSN gene expression was observed by cell viability assay, western blot, and AV/PI flow cytometry. Drug resistance concerning cancer stemness was confirmed with sphere formation and ALDH activity assay. Immunofluorescence and immunoprecipitation were performed. The combination index(CI), which is to define the synergism of combined treatment was calculated with the Compusyn program. Results: The cohort with METABRIC and our in-house clinical data showed concordant findings that overexpressed MSN mRNA and protein expressions have a poor prognosis in TNBC patients. The MSN protein expression in TNBC was increased compared to the protein level in both the normal human tissues and non-TNBC cell lines. Overexpressed MSN induced high cell proliferation activity, invasion, and migration ability. The apoptosis rate (AV+/PI+) along with cleaved PARP and caspase-3 expression was increased in TNBC cell lines with MSN downregulation. Further tests to determine the role of MSN in adriamycin resistance showed an increased number and size of spheres in the MSN overexpressed cell lines. Moreover, the protein and mRNA levels of MSN expression in MDA-MB-231/ADR12 were significantly higher than the level in the matched parental cell line. MSN and phospho-STAT3(T705) were increased by treatment of IL-6 in TNBC cell lines. The direct binding between MSN and STAT3, and the co-localization of MSN and pSTAT3 were consistently confirmed by co-immunoprecipitation and immunofluorescence, which were all activated by IL-6. Blocking the STAT3 pathway with atovaquone restored ADR response in MSN overexpressed tumor cells. CI value on the combined treatment of ADR and atovaquone in the MDA-MB-231/ADR12 cell line showed higher synergetic efficacy than the parental cell line. Conclusion: This research demonstrates the involvement of the MSN in doxorubicin resistance through IL-6/MSN/STAT3 pathway and provides a novel therapeutic candidate for TNBC patients. Citation Format: Cheng Hyun Lee, Da Sol Kim, Soo Young Park, Han Suk Ryu. Moesin-induced adriamycin resistance through IL-6/MSN/STAT3 axis and therapeutic efficacy of atovaquone in chemotherapy resistant triple-negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2774.

Ebselen oxide and derivatives are new allosteric HER2 inhibitors for HER2-positive cancers.

Human epidermal growth factor receptor 2 (ErbB2/HER2) is a tyrosine kinase receptor that is overexpressed in 25% of primary human breast cancers, as well as in multiple other cancers. HER2-targeted therapies improved progression-free and overall survival in patients with HER2+ breast cancers. However, associated resistance mechanisms and toxicity highlight the need for new therapeutic approaches for these cancers. We recently established that, in normal cells, HER2 is stabilized in a catalytically repressed state by direct interaction with members of the ezrin/radixin/moesin (ERM) family. In HER2-overexpressing tumors, the low expression of moesin contributes to the aberrant activation of HER2. Through a screen designed to find moesin-mimicking compounds, we identified ebselen oxide. We show that ebselen oxide, and some derivatives, conferred an efficient allosteric inhibition of overexpressed HER2, as well as mutated and truncated oncogenic forms of HER2, which are resistant to current therapies. Ebselen oxide selectively inhibited anchorage-dependent and -independent proliferation of HER2+ cancer cells and showed a significant benefit in combination with current anti-HER2 therapeutic agents. Finally, ebselen oxide significantly blocked HER2+ breast tumor progression in vivo. Collectively, these data provide evidence that ebselen oxide is a newly identified allosteric inhibitor of HER2 to be considered for therapeutic intervention on HER2+ cancers.

Post-warming culture of human vitrified blastocysts with prolactin improves trophoblast outgrowth

BackgroundHuman embryos express the prolactin (PRL) receptor at the morula and blastocyst stages. Treatment with PRL from cleavage to the blastocyst stage improves blastocyst outgrowth on fibronectin-coated dishes. However, whether post-warming PRL treatment of blastocysts cultured without PRL could improve outgrowth competence remains unknown. Furthermore, the optimal time for post-warming PRL treatment remains to be ascertained. This study investigated the effects of PRL treatment during recovery culture on human blastocyst outgrowth and its related genes.MethodsIn total, 374 discarded vitrified blastocysts were randomly allocated to two groups, to be cultured with (n = 208) or without PRL (control; n = 166) for 120 min for recovery, and then plated on fibronectin-coated dishes. The expression level of PRL-interacting genes, blastocyst adhesion rate, outgrowth area, distance of trophoblast migration, and outgrowth degeneration were examined.ResultsThe mRNA expression of ezrin, radixin, and moesin, which regulate cell adhesion and invasion by controlling actin reorganization during epithelial-to-mesenchymal transition (EMT), was stimulated by PRL treatment for 120 min. The expression of EMT-related genes, transforming growth factor β1, snail1, and twist1 was also promoted following treatment with PRL for 120 min. PRL-treated blastocysts also exhibited augmented expression of cadherin 2 and transcriptional repression of cadherin 1. Higher mRNA expression of integrin-based focal adhesion-related genes, ITGA5 and ITGB1, was observed after treatment with PRL for 120 min than in the non- and shorter-treatment groups. PRL treatment for 120 min did not alter the rate of blastocyst adhesion to fibronectin-coated dishes 96 h after the outgrowth culture assay. However, multiple linear regression analysis revealed that the outgrowth area was significantly increased in PRL-treated blastocysts. The migration distance of trophoblast cells was significantly increased and degeneration rate was significantly decreased after PRL treatment. Furthermore, a more beneficial effect of PRL treatment on blastocyst outgrowth was observed when the blastocysts were vitrified on day 5 than when they were vitrified on day 6.ConclusionsPost-warming culture of human vitrified blastocysts with PRL for 120 min promoted trophoblast outgrowth in vitrified human blastocysts. Furthermore, PRL treatment may reduce outgrowth degeneration by increasing resistance to apoptosis during trophoblast migration.

To evaluate an association between prognostic significance of Moesin with histopathological grading of oral squamous cell carcinoma: A systematic review.

The aim of the present Aetiology/Risk type and Prognostic type of systematic review is to evaluate the value of Moesin as a biomarker of invasiveness in Oral Squamous Cell Carcinoma patients and to review/assess the available evidence regarding the prospective prognostic association between Moesin and histopathological grading of OSCC to enhance the quality of life and survival rate of oral cancer patients. A systematic wide-range literature search was performed by authors (BS, KS, and DK) till October 2022 using both, electronic search media and manual search by hand, searching appropriate journals as per the focussed guiding question and inclusion/exclusion criteria. Major databases such as Scopus, EMBASE, Web of Science, Cochrane central register for controlled trials, PubMed & Google Scholar were conducted by two calibrated reviewers independently to gauge the association between the prognostic significance of Moesin with histopathological grading of oral squamous cell carcinoma. As this study is based on tissue samples of oral squamous cell carcinoma patients, all the selected studies were mostly, cross-sectional studies, and retrospective in nature. The studies were integrated with this review to gauge the association between the prognostic significance of Moesin with histopathological grading of oral squamous cell carcinoma (OSCC). The review included a total of 7 studies with tissue samples of 645 cases. The prime outcome was to assess the immunoexpression of Moesin among the different histopathological grades i.e well-differentiated SCC, moderately differentiated SCC, and poorly differentiated SCC and the subordinate outcome was to consider the extent of strong immunoexpression characteristics (cytoplasmic, membranous and mixed type) in different grades of OSCC as well as to correlate with morbidity, mortality, and/or 5 years or 10 years survival rate. The results were analyzed and presented narratively using the Critical Appraisal Tools developed by the University Of Oxford; Risk of Bias - Cochrane Risk of Bias tool - RoB 2.0, and GRADE-pro (Grading of Recommendations, Assessment, Development, and Evaluations) which rates the features of the evidence as high, moderate, low and very low. The risk of mortality expressed in terms of Hazard ratio has been elicited as a 1.37 times higher rate of mortality in the advanced histopathological stages of the OSCC cases. As the sample size of this review was insignificant, therefore, the authors have incorporated hazard ratios of some other studies of carcinomas in diverse sites in the body to give a flavor of prognostic outcomes of Moesin. It was observed that Moesin expression in Breast cancer and UADT carcinomas have a higher mortality rate as compared to OSCC and lung carcinoma cases and this decree strengthens our conviction that Moesin expression in the cytoplasm of advanced histopathological stages of cancer can be assumed as a sign of poor prognosis in all carcinomas including OSCC patients. A sample of seven studies is inadequate as definite evidence for claiming that Moesin is a strong biomarker of invasiveness in OSCC cases and more clinical trials need to be conducted on the prognostic efficacy of Moesin expression in the various histopathological grades of OSCC cases.

MiR-452-5p suppressed the metastasis of Non-small cell lung cancer through regulating Moesin.

Background: Non-small cell lung cancer (NSCLC) is a common malignant tumor, and it is characterized by high mortality. MicroRNA-452-5p (miR-452-5p) and Moesin (MSN) have been proved to be related with regulation of tumors. If miR-452-5p could regulate NSCLC through targeting MSN remain unclear. Methods: TargetScan data and GEPIA databases were used to predict binding site and analyze gene expression, respectively. EdU staining, wound healing, and Transwell assays were performed to measure cell proliferation, migration, and invasion, respectively. Results: The binding site between miR-452-5p and MSN was predicted and validated. Overexpression of miR-452-5p cell lines were constructed, and miR-452-5p mimics markedly inhibited the migration, invasion, and proliferation ability of both H322 and A549 cells, but these effects of miR-452-5p were reversed by pcDNA-MSN. pcDNA-MSN significantly reversed the influence of miR-452-5p mimics on the EMT related proteins expression in H322 and A549 cell lines by decreasing E-cadherin and increasing N-cadherin. Significant higher expression of MSN in lung adenocarcinoma and lung squamous cell carcinoma was observed through GEPIA and TCGA data base analysis. Higher expression of MSN is positively correlated with advanced lung cancer and suggests poor prognosis. Conclusions: We demonstrated that miR-452-5p modulated the cell proliferation, migration, invasion, and EMT process of H322 and A549 cell lines through targeting MSN. This research might provide a novel prevention and treatment target for NSCLC.

EXPRESSION OF ANTIGEN THOMSEN–FRIEDENREICH RECOGNIZED BY Amaranthus leucocarpus LECTIN IN MCF CELLS STIMULATED WITH LIPOPOLYSACCHARIDE

Altered glycosylation is a characteristic of cancer cells, where the overexpression of truncated antigens such as the Thomsen–Friedenreich (TF) antigen (Galβ1, 3GalNAcα1, O-Ser / Thr) The TF antigen is specifically recognized by the Amaranthus leucocarpus (ALL). The MCF-7 breast cancer cell line maintains characteristics similar to differentiated mammary epithelial cells. It has been linked to stimulation of breast cancer cells with lipopolysaccharide, with a higher risk of metastasis in this type of cancer. In this work the expression of TF antigen and moesin in MCF-7 stimulated with LPS at concentration of 20 ng / ml cells was determined, by flow cytometry and fluorescence microscopy. MCF-7 cells express 45% of TF antigen without stimulus with LPS, the expression of the TF antigen decreases with the time of LPS stimulation. Moesin expression increases with LPS stimulation time. A double-positive MCF-7 population for moesin and a TF-antigen of 6.34% were identified by cytometry at 6 hours of LPS stimulation, compared to cells with no stimulus, whose double positivity was 2.86%. Our results suggests that moesin could be Amaranthus leucocarpus receptor in MCF-7 cells.

Role of moesin and its phosphorylation in VE-cadherin expression and distribution in endothelial adherens junctions

Background and aimVascular endothelial cadherin (VE-cadherin) is an important element of adherens junctions (AJs) between endothelial cells. Its expression and proper distribution are critical for AJ formation and vascular integrity. Our previous studies have demonstrated that moesin phosphorylation mediated the hyper-permeability in endothelial monolayer and microvessels. However, the role of moesin and its phosphorylation in VE-cadherin expression and distribution is not clear. Methods and resultsIn vivo, expression of VE-cadherin was significantly reduced in retina and other various tissues in moesin knock out mice (Msn-/Y). In vitro, by regulating moesin expression with siRNA and adenovirus transfection, we verified that moesin has an effect on VE-cadherin expression in HUVECs, while transcription factor KLF4 may participate in this process. In addition, treatment of advanced glycation end products (AGEs) induced abnormal distribution of VE-cadherin in retinal microvessels from C57BL/6 wild type mice, and in vitro studies indicated that moesin Thr558 phosphorylation had a critical role in AGE-induced VE-cadherin internalization from cytomembrane to cytoplasm. Further investigation demonstrated that the inhibition of F-actin polymerization with cytochalasin D could abolish AGE- and Thr558 phosphor-moesin-mediated VE-cadherin internalization. ConclusionThis study suggests that moesin regulates VE-cadherin expression through KLF4 and the state of moesin phosphorylation at Thr558 affects the integrity of VE-cadherin-based AJs. Thr558 phosphor-moesin mediates AGE-induced VE-cadherin internalization through cytoskeleton reassembling.

Slug Mediates MRP2 Expression in Non-Small Cell Lung Cancer Cells.

Transcriptional factors, such as Snail, Slug, and Smuc, that cause epithelial-mesenchymal transition are thought to regulate the expression of Ezrin, Radixin, and Moesin (ERM proteins), which serve as anchors for efflux transporters on the plasma membrane surface. Our previous results using lung cancer clinical samples indicated a correlation between Slug and efflux transporter MRP2. In the current study, we aimed to evaluate the relationships between MRP2, ERM proteins, and Slug in lung cancer cells. HCC827 cells were transfected by Mock and Slug plasmid. Both mRNA expression levels and protein expression levels were measured. Then, the activity of MRP2 was evaluated using CDCF and SN-38 (MRP2 substrates). HCC827 cells transfected with the Slug plasmid showed significantly higher mRNA expression levels of MRP2 than the Mock-transfected cells. However, the mRNA expression levels of ERM proteins did not show a significant difference between Slug-transfected cells and Mock-transfected cells. Protein expression of MRP2 was increased in Slug-transfected cells. The uptake of both CDCF and SN-38 was significantly decreased after transfection with Slug. This change was abrogated by treatment with MK571, an MRP2 inhibitor. The viability of Slug-transfected cells, compared to Mock cells, significantly increased after incubation with SN-38. Thus, Slug may increase the mRNA and protein expression of MRP2 without regulation by ERM proteins in HCC827 cells, thereby enhancing MRP2 activity. Inhibition of Slug may reduce the efficacy of multidrug resistance in lung cancer.

Could Moesin Be a New Marker for Indicating Progression in Endometrial Cancer?

AimThis study aims to determine an important parameter in progression from pre-invasive lesions of endometrium to endometrial cancer and also evaluate the effect of this parameter on the progression of endometrial cancer.Material and MethodIn our study,30 patients with normal endometrial tissue (group 1), 56 patients who had endometrial hyperplasia without atypia (group 2), 36 patients who had endometrial hyperplasia with atypia (group 3), and 63 patients with endometrial cancer (group 4) were included. Age, parity, body-mass index, systemic diseases, and tumor markers of patients were evaluated. Expression levels of Ezrin, Radixin, and Moesin proteins were immunohistochemically evaluated in terms of frequency, intensity, and score value.ResultsWhen we compared hyperplasia cases with or without atypia; frequency, and score value of ezrin expression and frequency, intensity, and score value of moesin expression was significantly higher in patients who had hyperplasia with atypia (p:0.000 p:0.001 p:0.003, p:0.032 p: 0.035 p:0.015 p:0.005, respectively). It was observed that the frequency and score value of moesin expression were significantly higher in patients with endometrial cancer when compared with patients who had hyperplasia with atypia (p:0.003 p:0.045). The frequency of moesin expression was significantly higher in patients who had postoperative mortality (p:0.030 p:0.039).ConclusionIncreased frequency of moesin expression in the preoperative period in patients with atypical hyperplasia should alert the surgeon in terms of malignancy. If the frequency of moesin expression increases in cases with endometrial cancer, the patient should be followed closely in terms of progression in the postoperative period.

RhoJ facilitates angiogenesis in glioblastoma via JNK/VEGFR2 mediated activation of PAK and ERK signaling pathways.

Glioblastoma (GBM) is a highly vascularized malignant tumor that depends on new blood vessel formation. Small molecules targeting the angiogenic process may be an effective anti-GBM therapeutic strategy. We previously demonstrated that RhoJ promoted the progression and invasion of GBM. RhoJ has also been shown to be expressed in endothelial cells and plays an important role in regulating endothelial cell migration and tumor angiogenesis. Therefore, we aimed to evaluate the role and mechanism of actions of RhoJ in GBM angiogenesis. We analyzed the expression of RhoJ in different grade gliomas and investigated its role in GBM angiogenesis in vivo and in vitro. Furtherly, RNA sequencing (RNA-seq), Western blotting and immunofluorescence were performed to identify the molecular mechanism of RhoJ in regulating endothelial cell behavior and GBM angiogenesis. Here, we found that silencing RhoJ resulted in inhibition of HUVEC cell migration and blood vessel formation. Overexpression of RhoJ promoted the expression of CD31, EpCAM and moesin, suggesting RhoJ facilitated angiogenesis and the malignant progression of GBM. RNA-seq data showed that VEGF/TNF signaling pathway positively regulated RhoJ. The expression levels of RhoJ was upregulated with the stimulation of VEGF, and reduced by the treatment of JNK inhibitor SP600125. It was also found that the activity of PAK-BRAF-ERK was down-regulated upon RhoJ and JNK knockdown. In conclusion, these results suggested that RhoJ plays an essential role in regulating GBM angiogenesis through the JNK/VEGFR2-PAK-ERK signaling pathway and there might exist a VEGF-JNK/ERK-VEGF circuitry. Thus, RhoJ may be a candidate therapeutic target for anti-angiogenesis treatment in GBM.

The Expression of Rab8, Ezrin, Radixin and Moesin in the Ciliary Body of Cynomolgus Monkeys.

The purpose of this study was to determine what proteins are present in the ciliary body (CB). To accomplish this, we conducted a proteomic analysis of the CB of cynomolgus monkeys. We also determined the location of the proteins in CB by immunohistology. The eyes of euthanized cynomolgus monkeys were enucleated, and the CB, were isolated from the eyes. Proteins were extracted from the CB and determined by liquid chromatography-mass spectrometry. Separated CB epithelial cells were cultured, and the proteins expressed in the CB were determined by Western blotting. The location of these proteins in the CB was determined by immunohistochemical staining. We also investigated whether adding dexamethasone to the culture medium changed protein expression by the epithelial cells. Proteomic analysis of the CBs showed that 813 proteins were expressed in the epithelium and stroma. These proteins included the small guanosine triphosphate-binding protein Rab8 and the ezrin/radixin/moesin (ERM) family. Tissue and immunohistological staining confirmed the colocalization of these proteins in non-pigmented CB epithelium. Western blotting of cultured CB epithelial cell lysates showed a tendency that adding dexamethasone changed Rab8 protein expression levels. Proteomic analysis of CBs identified several proteins involved in the transport and secretion of proteins. These proteins may be involved in the production of aqueous humor and protein secretion by the CB.

Allosteric Inhibition of HER2 by Moesin-Mimicking Compounds Targets HER2-Positive Cancers and Brain Metastases.

Therapies targeting the tyrosine kinase receptor HER2 have significantly improved survival of patients with HER2+ cancer. However, both de novo and acquired resistance remain a challenge, particularly in the brain metastatic setting. Here we report that, unlike other HER tyrosine kinase receptors, HER2 possesses a binding motif in its cytosolic juxtamembrane region that allows interaction with members of the Ezrin/Radixin/Moesin (ERM) family. Under physiologic conditions, this interaction controls the localization of HER2 in ERM-enriched domains and stabilizes HER2 in a catalytically repressed state. In HER2+ breast cancers, low expression of Moesin correlated with increased HER2 expression. Restoring expression of ERM proteins in HER2+ breast cancer cells was sufficient to revert HER2 activation and inhibit HER2-dependent proliferation. A high-throughput assay recapitulating the HER2-ERM interaction allowed for screening of about 1,500 approved drugs. From this screen, we found Zuclopenthixol, an antipsychotic drug that behaved as a Moesin-mimicking compound, because it directly binds the juxtamembrane region of HER2 and specifically inhibits HER2 activation in HER2+ cancers, as well as activation of oncogenic mutated and truncated forms of HER2. Zuclopenthixol efficiently inhibited HER2+ breast tumor progression in vitro and in vivo and, more importantly, showed significant activity on HER2+ brain tumor progression. Collectively, these data reveal a novel class of allosteric HER2 inhibitors, increasing the number of approaches to consider for intervention on HER2+ breast cancers and brain metastases. SIGNIFICANCE: This study demonstrates the functional role of Moesin in maintaining HER2 in a catalytically repressed state and provides novel therapeutic approaches targeting HER2+ breast cancers and brain metastasis using Moesin-mimicking compounds.

Carnitine/organic cation transporter 1 precipitates the progression of interstitial fibrosis through oxidative stress in diabetic nephropathy in mice

Carnitine/organic cation transporter 1 (OCTN1) is the only known uptake transporter for ergothioneine which is a food-derived strong antioxidant amino acid that is absorbed by OCTN1. We previously reported the roles of OCTN1/ergothioneine in the progression of kidney fibrosis in ischemic kidney disease. In this study, we evaluated the roles of OCTN1 in the progression of diabetic kidney disease. A diabetic kidney disease model was induced in octn1 knockout and wild-type mice by streptozotocin (STZ). Oxidative stress, represented by urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG), were higher in the octn1 knockout mice. Azan- and Sirius red-positive areas increased significantly in the octn1 knockout mice. Gene expression was evaluated by cluster analysis, and shown to be different in the octn1 knockout mice compared with the wild-type mice. In a pathway analysis, the pathway associated with the cytoskeleton and cell adhesion increased. In accordance with interstitial fibrosis in octn1 knockout mice, gene expression of moesin in the injured kidney, known as an associated protein of cytoskeleton and cell membranes, was doubled 28 weeks after STZ injection. In addition, the moesin protein was expressed in a part of α-SMA-positive renal tubular epithelial cells. These findings were confirmed by cultured murine proximal tubular epithelial cells: The expression of moesin was induced under oxidative stress with hydrogen peroxide. These data indicate that OCTN1 would play some roles in progression of interstitial fibrosis under oxidative stress via moesin expression in diabetic kidney disease.

Identification of skin aging biomarkers correlated with the biomechanical properties.

Skin aging can be described as a combination of intrinsic and extrinsic aging. Various parameters for evaluating skin characteristics have been proposed. However, an accurate biomarker for skin aging and the relationship between biomarkers and biomechanical parameters of the skin is yet to be explored. This study included 20 subjects by age. Skin aging was measured using non-invasive devices. Skin tissues were acquired through punch biopsy for immunohistochemistry and qRT-PCR of skin aging biomarkers, and analyzed correlation both, validated their use. Biomechanical properties of skin aging decreased with age. Among the biomarkers previously reported, we found that the expression of Moesin, TXNDC5, RhoGDI, and RSU1 decreased, while that of Vimentin and FABP5 increased with age. Pearson correlation showed that the expression levels of TXNDC5, RhoGDI, RSU1, and Vimentin were significantly correlated with the results of non-invasive measurements. In addition, the expression of TXNDC5, RhoGDI, and RSU1 increased, while that of Vimentin decreased, in skin explants upon treatment with one of the anti-aging compounds, retinoic acid. From this study, we identified practical molecular biomarkers of skin aging, TXNDC5, RhoGDI, RSU1, and Vimentin, which correlated with the skin biomechanical properties of skin aging.

Moesin as a prognostic indicator of lung adenocarcinoma improves prognosis by enhancing immune lymphocyte infiltration

BackgroundEzrin-radixin-moesin (ERM) have been explored in many cancer processes. Moesin, as its component, has also been found to play an important role in the prognosis of cancer patients, tumor metastasis, drug resistance, and others. Especially in regulating the immunity, but most results came from direct studies on immune cells, there is no clear conclusion on whether moesin has similar effects in tumor cells. And moesin has certain research results in many cancers in other aspects, but there are few about moesin in lung adenocarcinoma (LUAD).MethodsWe detect the expression of moesin in 82 LUAD and matched normal tissue samples by immunohistochemistry. Besides, for the pathological feature, we did a detailed statistical analysis. And with the help of various databases, we have done in-depth exploration of moesin’s ability to enhance the extent of immune lymphocyte infiltration.ResultsMoesin is a poor expression in lung cancer tissues than the corresponding normal samples. And this phenomenon had a strongly associated with the prognosis and TNM stage of these LUAD patients. Moesin can enhance the infiltration of multiple immune lymphocytes in lung cancer. And this may be related to the interaction between moesin and various inflammatory molecules.ConclusionsMoesin is a newly index for the prognosis of LUAD and improves the prognosis of LUAD patients by regulating a variety of inflammation-related molecules to enhance immune lymphocytes infiltration.

Patients with Proliferative Lupus Nephritis Have Autoantibodies That React to Moesin and Demonstrate Increased Glomerular Moesin Expression.

Kidney involvement in systemic lupus erythematosus (SLE)—termed lupus nephritis (LN)—is a severe manifestation of SLE that can lead to end-stage kidney disease (ESKD). LN is characterized by immune complex deposition and inflammation in the glomerulus. We tested the hypothesis that autoantibodies targeting podocyte and glomerular cell proteins contribute to the development of immune complex formation in LN. We used Western blotting with SLE sera from patients with and without LN to identify target antigens in human glomerular and cultured human-derived podocyte membrane proteins. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), we identified the proteins in the gel regions corresponding to reactive bands observed with sera from LN patients. We identified 102 proteins that were present in both the podocyte and glomerular samples. We identified 10 high-probability candidates, including moesin, using bioinformatic analysis. Confirmation of moesin as a target antigen was conducted using immunohistochemical analysis (IHC) of kidney biopsy tissue and enzyme-linked immunosorbent assay (ELISA) to detect circulating antibodies. By IHC, biopsies from patients with proliferative lupus nephritis (PLN, class III/IV) demonstrated significantly increased glomerular expression of moesin (p < 0.01). By ELISA, patients with proliferative LN demonstrated significantly increased antibodies against moesin (p < 0.01). This suggests that moesin is a target glomerular antigen in lupus nephritis.