Clinical value of ezrin expression in primary osteosarcoma

Mass Spectrometric-Based Proteomics for Biomarker Discovery in Osteosarcoma: Current Status and Future Direction

Due to a lack of novel therapies and biomarkers, the clinical outcomes of osteosarcoma patients have not significantly improved for decades. The advancement of mass spectrometry (MS), peptide quantification, and downstream pathway analysis enables the investigation of protein profiles across a wide range of input materials, from cell culture to long-term archived clinical specimens. This can provide insight into osteosarcoma biology and identify candidate biomarkers for diagnosis, prognosis, and stratification of chemotherapy response. In this review, we provide an overview of proteomics studies of osteosarcoma, indicate potential biomarkers that might be promising therapeutic targets, and discuss the challenges and opportunities of mass spectrometric-based proteomics in future osteosarcoma research.

Ezrin gone rogue in cancer progression and metastasis: An enticing therapeutic target

Cancer metastasis is the primary cause of morbidity and mortality in cancer as it remains the most complicated, devastating, and enigmatic aspect of cancer. Several decades of extensive research have identified several key players closely associated with metastasis. Among these players, cytoskeletal linker Ezrin (the founding member of the ERM (Ezrin-Radixin-Moesin) family) was identified as a critical promoter of metastasis in pediatric cancers in the early 21st century. Ezrin was discovered 40 years ago as a aminor component of intestinal epithelial microvillus core protein, which is enriched in actin-containing cell surface structures. It controls gastric acid secretion and plays diverse physiological roles including maintaining cell polarity, regulating cell adhesion, cell motility and morphogenesis. Extensive research for more than two decades evinces that Ezrin is frequently dysregulated in several human cancers. Overexpression, altered subcellular localization and/or aberrant activation of Ezrin are closely associated with higher metastatic incidence and patient mortality, thereby justifying Ezrin as a valuable prognostic biomarker in cancer. Ezrin plays multifaceted role in multiple aspects of cancer, with its significant contribution in the complex metastatic cascade, through reorganizing the cytoskeleton and deregulating various cellular signaling pathways. Current preclinical studies using genetic and/or pharmacological approaches reveal that inactivation of Ezrin results in significant inhibition of Ezrin-mediated tumor growth and metastasis as well as increase in the sensitivity of cancer cells to various chemotherapeutic drugs. In this review, we discuss the recent advances illuminating the molecular mechanisms responsible for Ezrin dysregulation in cancer and its pleiotropic role in cancer progression and metastasis. We also highlight its potential as a prognostic biomarker and therapeutic target in various cancers. More importantly, we put forward some potential questions, which we strongly believe, will stimulate both basic and translational research to better understand Ezrin-mediated malignancy, ultimately leading to the development of Ezrin-targeted cancer therapy for the betterment of human life.

Osteosarcoma-Specific Genes as a Diagnostic Tool and Clinical Predictor of Tumor Progression

Simple Summary

The standard method for the diagnosis and monitoring of osteosarcoma is biopsy and tumor imaging, which causes discomfort to patients and is difficult to repeat. A blood sample can be used as a non-invasive method for monitoring tumor material. Vimentin and ezrin show clinical significance in samples obtained from OS patients but need circulating tumor cell purification, since they are expressed in leukocytes. Due to the low-temperature storage of the samples, it proved impossible to perform purification to remove the contamination. We propose that novel or OS-specific biomarkers using differential gene expression from the Gene Expression Omnibus (GEO) database is a promising approach for developing diagnostic and tumor progression strategies. Seven genes from the database showed significant expression in OS cell lines/primary cells compared to a normal blood donor, together with ezrin and VIM. The expression of the five candidate genes together with ezrin and vimentin were quantified by qRT-PCR and analyzed using a mathematical model with high efficiency to discriminate between OS patients and normal samples, resulting in the selection of three candidate genes: COL5A2 (one of the five from the database) as well as ezrin and VIM. Our study demonstrates that these genes in retrospective samples could serve as tools of OS detection and predictors of disease progression.

Abstract

A liquid biopsy is currently an interesting tool for measuring tumor material with the advantage of being non-invasive. The overexpression of vimentin and ezrin genes was associated with epithelial-mesenchymal transition (EMT), a key process in metastasis and progression in osteosarcoma (OS). In this study, we identified other OS-specific genes by calculating differential gene expression using the Gene Expression Omnibus (GEO) database, confirmed by using quantitative reverse transcription-PCR (qRT-PCR) to detect OS-specific genes, including VIM and ezrin in the buffy coat, which were obtained from the whole blood of OS patients and healthy donors. Furthermore, the diagnostic model for OS detection was generated by utilizing binary logistic regression with a multivariable fractional polynomial (MFP) algorithm. The model incorporating VIM, ezrin, and COL5A2 genes exhibited outstanding discriminative ability, as determined by the receiver operating characteristic curve (AUC = 0.9805, 95% CI 0.9603, 1.000). At the probability cut-off value of 0.3366, the sensitivity and the specificity of the model for detecting OS were 98.63% (95% CI 90.5, 99.7) and 94.94% (95% CI 87.5, 98.6), respectively. Bioinformatic analysis and qRT-PCR, in our study, identified three candidate genes that are potential diagnostic and prognostic genes for OS.

High expression of EZR (ezrin) gene is correlated with the poor overall survival of breast cancer patients

Background

To evaluate the EZR (ezrin) gene expression in breast cancer and correlation with the prognosis through bioinformatics analysis and immunohistochemistry assay.

Methods

EZR gene expression in breast cancer and corresponding normal breast tissue was compared in the TCGA database. Protein‐protein interaction (PPI) network relevant EZR was established through the STRING database. The correlation between EZR expression and prognosis of breast cancer was analyzed by the log‐rank analysis from the TCGA. Ezrin protein (coded by EZR) expression was also examined by immunohistochemistry assay in 120 breast cancer patients.

Results

EZR expression level in tumor tissue was significantly upregulated compared to that of normal breast tissue of breast cancer patients (P < 0.05). In the PPI analysis, there were 51 nodes and 455 edges in the network. The top 10 hub genes of the network were identified. High expression of EZR mRNA was correlated with poor overall survival (OS) of the breast cancer patients (HR = 1.40, P = 0.038). However, the disease‐free survival (DFS) of breast cancer patients did not correlate with the EZR mRNA level (HR = 0.86, P = 0.44). The ezrin protein expression was positive with uniform brown‐yellow granules in the cell membrane, cavity surface and cytoplasm of the breast cancer cells. Of the included 120 cancer samples, 98 cases were positive for ezrin expression and 22 were negative. No correlation was found between ezrin expression site and patients’ clinicopathological features.

Conclusion

EZR is upregulated in breast cancer and can be used as potential biomarker for overall survival.

The clinical prognostic significance of ezrin in patients with bone and soft tissue sarcomas: a meta-analysis

Ezrin is a member of the ezrin–radixin–moesin (ERM) protein family and has been shown to be associated with poor prognosis in patients with a variety of solid tumors. However, the clinical prognostic significance of ezrin in patients with bone and soft tissue sarcomas remains unclear. Here, we performed a systematic meta‐analysis by searching PubMed, the Cochrane Library Database, EMBASE, the Web of Science, and the CBM, WanFang Med Online and CNKI databases. In total, 19 studies with a total of 1316 bone and soft tissue sarcoma patients were included. Pooled analyses showed that ezrin overexpression was correlated with a higher rate of tumor metastasis (OR 6.59, 95% CI: 2.84–15.33, P < 0.01, P_FDR < 0.01) and recurrence (OR 3.18, 95% CI: 1.88–5.37, P < 0.01, P_FDR < 0.01) and a more advanced tumor grade (OR 3.252, 95% CI: 1.371–7.715, P = 0.01, P_FDR = 0.03). Moreover, elevated ezrin expression could predict poor OS (HR 3.02, 95% CI: 2.35–3.89, P < 0.01, P_FDR < 0.01), MFS (HR 5.22, 95% CI: 2.08–13.08, P < 0.01, P_FDR < 0.01), and EFS (HR 1.07, 95% CI: 1.03–1.11, P < 0.01, P_FDR < 0.01). Subgroup analyses revealed the underlying sources of heterogeneity. Publication bias was observed in the analysis of metastasis. Sensitivity analysis revealed that the results were robust. Our findings indicated that ezrin overexpression was significantly correlated with poor survival and more advanced tumor progression in bone and soft tissue sarcomas, which suggests that ezrin might be a valuable prognostic biomarker and a potential therapeutic target.

Forecast of actin-binding proteins as the oncotarget in osteosarcoma - a review of mechanism, diagnosis and therapy

Osteosarcoma (OS) is the most common bone malignant tumor with a high rate of lung metastasis and principally emerges in children and adolescents. Although neoadjuvant chemotherapy is widely used around the world, a high rate of chemoresistance occurs and frequently generates a poor prognosis. Therefore, finding a new appropriate prognostic marker for OS is a valuable research direction, which will give patients a better chance to receive proper therapy. Actin-binding proteins (ABPs) are a group of proteins that interact with actin cytoskeleton and play a crucial role in the regulation of the cell motility and morphology in eukaryotes. Meanwhile, ABPs also act as a bridge between the cytomembrane and nucleus, which transmit the outside-in and inside-out signals in cytoplasm. Furthermore, ABPs alter the dynamic structure of actin and regulate the invasion and metastasis of cancer. Hence, ABPs have a wide application in predicting the prognosis, and may be new targets, in tumor therapy. This review focuses on a series of ABPs and discusses their modulatory functions. It provides a new insight into the classification of ABPs’ functions in the process of invasion and metastasis in OS and illuminates the potential ability in predicting the prognosis of OS patients.

Differentially activated Src kinase in chemo-naïve human primary osteosarcoma cells and effects of a Src kinase inhibitor

The therapeutic treatment of osteosarcoma (OS), a rare malignant teenage cancer of the skeletal system, still represents a great challenge as patient survival after conventional protocol chemotherapy treatment has not improved in the last four decades leaving poor patient prognoses. Therefore, many efforts have been done to find increasingly reliable OS cell models and to identify "druggable" targets in OS, in order to identify novel effective therapeutic approaches and treatment strategies. In this contest, the more successful use of patient-derived cell cultures in respect to human commercial lines and findings of Src kinase deregulation in cancer, prompted us to study for the first time the activation state of Src and the potential activity of our Src inhibitor SI-83 in a number of chemo-naïve patient-derived primary OS cells. We here demonstrate that Src is hyperactivated in OS cells in respect to the nonmalignant counterpart and that SI-83 is able to strongly decrease cell viability, proliferation, Src₄₁₆ phosphorylation, and cell migration. © 2017 BioFactors, 43(6):801-811, 2017.

The Prognostic Role of Ezrin and HER2/neu Expression in Osteosarcoma

Osteosarcoma is the most common primary malignant bone tumor in Egypt. Ezrin is involved in cell adhesion to the extracellular matrix and in cell-cell interactions facilitating metastasis. HER2/neu is overexpressed in breast cancer and other types of cancer. This study aimed to assess the expression of ezrin and HER2/neu in 57 primary osteosarcoma cases and to correlate their expression with the available clinicopathologic parameters and the overall, metastasis-free and event-free survival. Both ezrin and HER2/neu were not expressed in the normal bone and they were upregulated in 82.5% and 71.9% of osteosarcoma, respectively. Positive ezrin expression was significantly associated with young age (below 25 y) (P=0.01), high grade (P=0.001), and short survival time (P=0.0001). Positive HER2/neu expression was significantly associated with high-grade osteosarcoma (P=0.04). Membranous HER2/neu expression was the only factor that showed significant impact on metastasis-free (P=0.002) and event-free survival (P=0.002). Ezrin was significantly correlated with HER2/neu expression (P=0.02). Advanced stage (P=0.0001), metastasis (P=0.0001), and recurrence (P=0.01) were the factors affecting the overall survival of osteosarcoma patients. Ezrin and HER2/neu are overexpressed and coexpressed in osteosarcoma with adverse prognostic features such as high grade. Membranous pattern of HER2/neu seems to be more important than the cytoplasmic pattern because of its impact on metastasis-free and event-free survival. Therefore, ezrin and HER2/neu could be potential prognostic markers and treatment targets for osteosarcoma.

The clinical significance of the Ezrin gene and circulating tumor cells in osteosarcoma

Purpose

The aim of this study was to investigate the clinical significance of circulating tumor cells (CTCs) in the peripheral blood of an osteosarcoma and the Ezrin gene expressed in CTCs.

Patients and methods

CTC enrichment was done with CanPatrol™ CTC enrichment technique in 41 patients with osteosarcoma. The characterization of CTCs was performed using a multiple messenger RNA in situ analysis (MRIA). The expression of the Ezrin gene in CTCs was detected by RNA probe technology. The correlations of CTC counts, cell type and the expression level of the Ezrin gene with clinical stage and metastasis of osteosarcoma were analyzed using SPSS 16.0 software.

Results

The CTC counts correlated significantly with Enneking stage (P<0.001). The ratio of mesenchymal CTCs correlated with the distant metastases (P<0.001). Ezrin gene expression in CTCs correlated significantly with distant metastases (χ²=152.51, P=0.000).

Conclusion

The ratio of mesenchymal CTCs in the peripheral blood of osteosarcoma correlates with distant metastases. High expression of Ezrin gene in CTCs correlates with distant metastases.

Correlation of Ezrin Expression Pattern and Clinical Outcomes in Ewing Sarcoma

Background. Ezrin is a membrane-cytoskeleton linker protein that has been associated with metastasis and poor outcomes in osteosarcoma and high-grade soft tissue sarcomas. The prognostic value of ezrin expression in Ewing sarcoma is unknown. Methods. The relationship between ezrin expression and outcome was analyzed in a cohort of 53 newly diagnosed Ewing sarcoma patients treated between 2000 and 2011. The intensity and proportion of cells with ezrin immunoreactivity were assessed in diagnostic tumor tissue using a semiquantitative scoring system to yield intensity and positivity scores for each tumor. Results. Ezrin expression was detected in 72% (38/53) of tumor samples. The proportion of patients with metastatic disease was equal in the positive and negative ezrin expression groups. There was no significant difference in the 5-year event-free survival (EFS) between patients with positive versus negative ezrin expression. Patients whose tumor sample showed high ezrin intensity had significantly better 5-year EFS when compared to patients with low/no ezrin intensity (78% versus 55%; P = 0.03). Conclusions. Ezrin expression can be detected in the majority of Ewing sarcoma tumor samples. Intense ezrin expression may be correlated with a favorable outcome; however further investigation with a larger cohort is needed to validate this finding.

Re-calculating! Navigating through the osteosarcoma treatment roadblock

The survival rates for patients with osteosarcoma have remained almost static for the past three decades. Current standard of care therapy includes chemotherapies such as doxorubicin, cisplatin, and methotrexate along with complete surgical resection and surgery with or without ifosfamide and etoposide for relapse, though outcomes are hoped to be improved through clinical trials. Additionally, increased understanding of the genetics, signaling pathways and microenvironmental factors driving the disease have led to the identification of promising agents and potential paths towards translation of an exciting array of novel targeted therapies. Here, we review the mechanism of action of these emerging therapies and how, with clinical translation, they can potentially improve the survival rates for osteosarcoma patients in the near future.

Prognostic Value of Ezrin in Various Cancers: A Systematic Review and Updated Meta-analysis

More and more studies have investigated the effects of Ezrin expression level on the prognostic role in various tumors. However, the results remain controversial rather than conclusive. Here, we performed a systematic review and meta-analysis to evaluate the correlation of Ezrin expression with the prognosis in various tumors. the pooled hazard ratios (HR) with the corresponding 95% confidence intervals (95% CI) were calculated to evaluate the degree of the association. The overall results of fifty-five studies with 6675 patients showed that elevated Ezrin expression was associated with a worse prognosis in patients with cancers, with the pooled HRs of 1.86 (95% CI: 1.51–2.31, P < 0.001) for over survival (OS), 2.55 (95% CI: 2.14–3.05, P < 0.001) for disease-specific survival (DFS) and 2.02 (95% CI: 1.13–3.63, P = 0.018) for disease-specific survival (DSS)/metastasis-free survival (MFS) by the random, fixed and random effect model respectively. Similar results were also observed in the stratified analyses by tumor types, ethnicity background and sample source. This meta-analysis suggests that Ezrin may be a potential prognostic marker in cancer patients. High Ezrin is associated with a poor prognosis in a variety of solid tumors.

Prognostic Significance of Serum Alkaline Phosphatase Level in Osteosarcoma: A Meta-Analysis of Published Data

Background. Serum alkaline phosphatase (SALP) is commonly elevated in osteosarcoma patients. A number of studies have investigated the prognostic role of SALP level in patients with osteosarcoma but yielded inconsistent results. Method. Systematic computerized searches were performed in PubMed, Embase, and Web of Science databases for relevant original articles. The pooled hazard ratios (HRs) and relative risks (RRs) with corresponding confidence intervals (CIs) were calculated to assess the prognostic value of SALP level. Results. Finally, 21 studies comprising 3228 patients were included. Overall, the pooled HRs of SALP suggested that elevated level had an unfavorable impact on osteosarcoma patients' overall survival (OS) (HR = 1.82; 95% CI: 1.61–2.06; p < 0.001) and event-free survival (EFS) (HR = 1.97; 95% CI: 1.61–2.42; p < 0.001). Combined RRs of SALP indicated that elevated level was associated with presence of metastasis at diagnosis (RR = 5.55; 95% CI: 1.61–9.49; p = 0.006). No significantly different results were obtained after stratified by variables of age range, cancer stage, sample size, and geographic region. Conclusion. This meta-analysis demonstrated that high SALP level is significantly associated with poor OS or EFS rate and presence of metastasis at diagnosis. SALP level is a convenient and effective biomarker of prognosis for osteosarcoma.

Establishment of Four New Human Primary Cell Cultures from Chemo-Naïve Italian Osteosarcoma Patients

Osteosarcoma (OS) is a primary highly malignant tumor of bone, affecting predominately adolescents and young adults between 10 and 20 years of age. OS is characterized by an extremely aggressive clinical course, with a rapid development of metastasis to the lung and distant bones.

Alteration of WWOX in human cancer: a clinical view

WWOX gene is located in FRA16D, the highly affected chromosomal fragile site. Its tumor suppressor activity has been proposed on a basis of numerous genomic alterations reported in chromosome 16q23.3-24.1 locus. WWOX is affected in many cancers, showing as high as 80% loss of heterozygosity in breast tumors. Unlike most tumor suppressors impairing of both alleles of WWOX is very rare. Despite cellular and animal models information on a WWOX role in cancer tissue is limited and sometimes confusing. This review summarizes information on WWOX in human tumors.

Correlations of ezrin expression with pathological characteristics and prognosis of osteosarcoma: a meta-analysis

We conducted a meta-analysis to comprehensively evaluate the correlations of ezrin expression with pathological characteristics and the prognosis of osteosarcoma. The MEDLINE (1966–2013), the Cochrane Library Database, EMBASE, CINAHL, Web of Science (1945–2013), and the Chinese Biomedical Database were searched without language restrictions. Meta-analyses conducted using STATA software were calculated. Ten studies met the inclusion criteria, including 459 patients with osteosarcoma. Meta-analysis results illustrated that ezrin expression may be closely associated with the recurrence of osteosarcoma or metastasis in osteosarcoma. Our findings also demonstrated that patients with grade III-IV osteosarcoma showed a higher frequency of ezrin expression than those with histological grade I-II osteosarcoma. Furthermore, we found that patients with positive expression of ezrin exhibited a shorter overall survival than those with negative ezrin expression. The results also indicated that positive ezrin expression was strongly correlated with poorer metastasis-free survival. Nevertheless, no significant relationships were observed between ezrin expression and clinical variables (age and gender). In the current meta-analysis, our results illustrated significant relationships of ezrin expression with pathological characteristics and prognosis of osteosarcoma. Thus, ezrin expression could be a promising marker in predicting the clinical outcome of patients with osteosarcoma.

Prognostic role of cytovillin expression in patients with osteosarcoma: a meta-analysis

Cytovillin plays structural and regulatory roles in the assembly and stabilization of specialized plasma membrane domains and in the tumor angiogenesis. Cytovillin expression has been proposed to be an effective biomarker of prognosis in patients with osteosarcoma, and many studies have been performed to assess the prognostic role of cytovillin expression in patients with osteosarcoma. We performed this meta-analysis to provide a comprehensive evaluation of the role of cytovillin expression on the overall survival rate by calculating the pooled risk ratio (RR) with corresponding 95% confidence interval (95% CI). Finally, eight studies with a total of 415 patients with osteosarcoma were included into the meta-analysis. Meta-analysis of total eight studies showed that cytovillin expression was obviously associated with lower overall survival rate in patients with osteosarcoma (RR = 0.41, 95% CI 0.28–0.58, P < 0.001). Meta-analysis of five studies with large sample still showed that cytovillin expression was obviously associated with lower overall survival rate (RR = 0.48, 95% CI 0.38–0.60, P < 0.001). In conclusion, the meta-analysis shows that cytovillin expression is obviously associated with lower overall survival rate in patients with osteosarcoma, and it is an effective biomarker of prognosis.

The prognostic value of elevated ezrin in patients with osteosarcoma

Published studies researching the prognostic significance of ezrin expression in patients with osteosarcoma are inconclusive and heterogeneous. We conducted a meta-analysis to assess its prognostic value more precisely. The hazard ratios with corresponding 95 % confidence intervals were calculated to evaluate the effects. Five studies with 318 osteosarcoma patients were included to estimate the relationship between ezrin and disease-free survival, and ezrin and overall survival. Compared with osteosarcoma patients with low or negative ezrin expression, patients with high ezrin expression tended to be associated with lower disease-free survival, but the difference was not significant. However, patients with high ezrin expression were obviously associated with lower overall survival. Therefore, the findings from this systematic review suggest that ezrin expression is an effective biomarker of prognosis in patients with osteosarcoma.

The β5/focal adhesion kinase/glycogen synthase kinase 3β integrin pathway in high-grade osteosarcoma: a protein expression profile predictive of response to neoadjuvant chemotherapy

To date, chemosensitivity to neoadjuvant chemotherapy of patients with high-grade osteosarcoma is evaluated on surgical resection by evaluation of the percentage of necrotic cells. As yet, no predictive profile of response to chemotherapy has been used in clinical practice. Because we have previously shown that the integrin pathway controls genotoxic-induced cell death and hypoxia, we hypothesized that in primary biopsies, expression of proteins involved in this pathway could be associated with sensitivity to neoadjuvant chemotherapy in high-grade osteosarcoma. We studied β1, β3, and β5 integrin expression and integrin-linked kinase, focal adhesion kinase (FAK), glycogen synthase kinase 3β (GSK3β), Rho B, angiopoietin-2, β-catenin, and ezrin expression by immunohistochemistry in 36 biopsies of osteosarcomas obtained before treatment. All patients received a chemotherapy regimen in the neoadjuvant setting. An immunoreactive score was assessed, combining the percentage of positive tumor cells and staining intensity. We evaluated the correlation of the biomarkers with response to chemotherapy, metastasis-free survival, and overall survival. A combination of 3 biomarkers (β5 integrin, FAK, and GSK3β) discriminated good and poor responders to chemotherapy, with the highest area under the curve (89.9%; 95% confidence interval, 77.4-1.00) and a diagnostic accuracy of 90.3%. Moreover, high expression of ezrin was associated with an increased risk of metastasis (hazard ratio, 3.93; 95% confidence interval, 1.19-12.9; P = .024). We report a protein expression profile in high-grade osteosarcoma associating β5 integrin, FAK, and GSK3β that significantly correlates with poor response to neoadjuvant chemotherapy. This biomarker profile could help select patients for whom an alternative protocol using inhibitors of this pathway can be proposed.

The Prognostic Role of Ezrin Immunoexpression in Osteosarcoma: A Meta-Analysis of Published Data

Background

The significance of ezrin immunoexpression and prognosis for osteosarcoma is still controversial. The aim was to provide a meta-analysis for ezrin immunoexpression and prognostic features of osteosarcoma patients.

Methods

A detailed search was made in MEDLINE, EMBASE and the Web of Knowledge for relevant original articles published in English; methodological quality of the included studies was also assessed. Two reviewers extracted data independently. Studies were pooled and summary hazard ratios (HRs) and odds ratio (ORs) with corresponding confidence intervals (CIs) were calculated.

Results

Final analysis of 318 patients from 5 eligible studies was performed. Combined HR of ezrin immunohistochemical staining suggested that positive immunoexpression had an unfavorable impact on osteosarcoma patients' overall survival (n = 223 in 4 studies; HR = 4.79; 95% CI: 1.50–15.30; P = 0.008) but not on event-free survival (n = 202 in 3 studies; HR = 1.59; 95% CI: 0.61–4.15; P = 0. 0.342). Combined OR of ezrin immunohistochemical staining indicated that positive immunoexpression was associated with recurrence (n = 134 in 2 studies; OR = 3.79; 95% CI: 1.49–9.64; P = 0.005) but not with serum ALP level (n = 160 in 2 studies; OR = 2.16; 95% CI: 0.09–52.50; P = 0.637) and histological response to neoadjuvant chemotherapy(n = 260 in 4 studies; OR = 0.87; 95% CI: 0.37–2.03; P = 0.740).

Conclusions

The results of this meta-analysis suggest that ezrin positive immunoexpression confers a higher risk of recurrence and a worse survival in osteosarcoma patients. Large prospective studies are needed to provide solid data to investigate the precise prognostic significance of ezrin.

Expression of HMGA1 and ezrin in laryngeal squamous cell carcinoma

CONCLUSION

The overexpression of HMGA1 or Ezrin may contribute to the carcinogenesis, development, and metastasis of laryngeal squamous cell carcinoma (LSCC).

OBJECTIVE

To investigate the expression of HMGA1 and Ezrin in LSCC and analyze their clinical significance.

METHODS

The expression of HMGA1 and Ezrin was analyzed by immunohistochemistry (IHC) in 50 cases of LSCC. Thirty cases of laryngeal polyp and 30 cases of atypical hyperplasia of larynx were studied as controls. The expression of HMGA1 and Ezrin was analyzed by real-time PCR and by Western blot in 30 cases of LSCC; samples from adjacent normal epithelial tissues in 30 cases were studied as controls.

RESULTS

(1) IHC revealed that the positive rate of HMGA1 protein was 68.0% (34/50), 53.3% (16/30), and 13. 3% (4/30) in LSCC, atypical hyperplasia of larynx, and laryngeal polyp (p < 0.05), and the positive rate of Ezrin protein was 64.0% (32/50), 50.0% (15/30), and 23.3% (7/30) (p < 0.01), respectively. (2) Real-time PCR demonstrated that the mean relative mRNA expression levels of HMGA1 in LSCC and in normal tissues were 2.41 ± 0.40 and 1.05 ± 0.18, respectively (p < 0.01). The mRNA levels of Ezrin in LSCC and in normal tissues were 1.79 ± 0.27 and 1.04 ± 0.22, respectively (p < 0.05). (3) Western blotting revealed that the mean relative protein expression levels of HMGA1 in LSCC and in normal tissues were 1.73 ± 0.60 and 0.35 ± 0.17, respectively (p < 0.01). The protein levels of Ezrin in LSCC and in normal tissues were 1.82 ± 0.77 and 0.42 ± 0.20, respectively (p < 0.01).

CD99 suppresses osteosarcoma cell migration through inhibition of ROCK2 activity

CD99, a transmembrane protein encoded by MIC2 gene is involved in multiple cellular events including cell adhesion and migration, apoptosis, cell differentiation and regulation of protein trafficking either in physiological or pathological conditions. In osteosarcoma, CD99 is expressed at low levels and functions as a tumour suppressor. The full-length protein (CD99wt) and the short-form harbouring a deletion in the intracytoplasmic domain (CD99sh) have been associated with distinct functional outcomes with respect to tumour malignancy. In this study, we especially evaluated modulation of cell-cell contacts, reorganisation of the actin cytoskeleton and modulation of signalling pathways by comparing osteosarcoma cells characterised by different metastasis capabilities and CD99 expression, to identify molecular mechanisms responsible for metastasis. Our data indicate that forced expression of CD99wt induces recruitment of N-cadherin and β-catenin to adherens junctions. In addition, transfection of CD99wt inhibits the expression of several molecules crucial to the remodelling of the actin cytoskeleton, such as ACTR2, ARPC1A, Rho-associated, coiled-coil containing protein kinase 2 (ROCK2) as well as ezrin, an ezrin/radixin/moesin family member that has been clearly associated with tumour progression and metastatic spread in osteosarcoma. Functional studies point to ROCK2 as a crucial intracellular mediator regulating osteosarcoma migration. By maintaining c-Src in an inactive conformation, CD99wt inhibits ROCK2 signalling and this leads to ezrin decrease at cell membrane while N-cadherin and β-catenin translocate to the plasma membrane and function as main molecular bridges for actin cytoskeleton. Taken together, we propose that the re-expression of CD99wt, which is generally present in osteoblasts but lost in osteosarcoma, through inhibition of c-Src and ROCK2 activity, manages to increase contact strength and reactivate stop-migration signals that counteract the otherwise dominant promigratory action of ezrin in osteosarcoma cells.

Effects of siRNA‑mediated Cdc2 silencing on MG63 cell proliferation and apoptosis

The present study aimed to determine the effect of small interfering RNA (siRNA)‑induced inhibition of cyclin‑dependent kinase 2 (Cdc2) expression on osteosarcoma MG63 cell proliferation and apoptosis. An siRNA expression plasmid, psilencer 2.1‑U6/Cdc2, targeting the Cdc2 gene, and a control psilencer 2.1‑U6/Scramble plasmid were constructed and transfected into MG63 cells using liposomes. Cdc2 expression in the MG63 cells was investigated by western blot analysis and real‑time polymerase chain reaction. Cell morphology was also examined. The effects of psilencer 2.1‑U6/Cdc2 on MG63 cell proliferation and the cell cycle were detected via MTT and flow cytometry, respectively. Expression levels of apoptosis‑related molecules, B‑cell lymphoma 2 (Bcl‑2) and Bcl‑2‑associated X (Bax) were determined by western blot analysis. MG63 cells stably transfected with the psilencer 2.1‑U6/Cdc2 plasmid (MG63‑siRNA/Cdc2) and negative control cells, MG63‑siRNA/Scramble, were successfully obtained. The silencing efficiencies of the Cdc2‑expressing mRNA and protein in MG63‑siRNA/Cdc2 were 86 and 89% of that of the control MG63‑siRNA/Scramble cells, respectively. Interference of Cdc2 expression inhibited MG63 cell proliferation and was demonstrated to significantly increase and decrease cells in the G2/M and S phases, respectively. Cdc2 expression silencing had negligible effects on Bcl‑2 and Bax expression in MG63 cells. In conclusion, silencing of Cdc2 expression suppresses proliferation of osteosarcoma MG63 cells but has negligible effects on apoptosis.

Clinicopathologic implication of ezrin expression in non-small cell lung cancer

Background

Ezrin, a member of the ezrin-radixin-moesin family, is implicated in tumor progression, metastatic dissemination, and adverse outcomes, in several cancer types. In this study, we explored the clinicopathological significance of ezrin expression in non-small cell lung carcinomas (NSCLCs).

Methods

Immunohistochemical analysis of tissue microarray with 112 surgically resected NSCLC specimens, was performed to examine the ezrin expression. We also correlated ezrin expression with other clinicopathological features and prognosis.

Results

The ezrin-positive group revealed significantly higher correlation with pleural invasion (p=0.016) and pathologic stage (p=0.050). Univariate survival analysis showed that ezrin-positive group had a significantly shorter cancer-specific survival than ezrin-negative group (p=0.016). Meanwhile, female (p=0.030), no pleural invasion (p=0.023), no lymphatic invasion (p=0.026), and early pathologic stage (p=0.008) significantly correlated with longer survival. Multivariate survival analysis showed that variables such as ezrin positivity (p=0.032), female (p=0.035), and early pathologic stage (p=0.001) were independent prognostic factors for NSCLC.

Conclusions

Ezrin might be a molecular marker to predict poor prognosis of NSCLC.

[Place of the pathologist in the management of primary bone tumors (osteosarcoma and Ewing's family tumors after neoadjuvant treatment)]

The survival of osteosarcoma and Ewing family tumours has been improved by the introduction of neoadjuvant chemotherapy. The response to preoperative chemotherapy is evaluated on the microscopic analysis of the surgical resection, by the percentage of tumour necrosis according to the Huvos and Rosen's grading. It remains the only reliable prognostic factor for patients and is used to guide the choice of post-operative chemotherapy. The macroscopic and microscopic management of the surgical resection (cf. supra) is essential and is the subject of a specific protocol. Several studies have been conducted to identify news factors able to predict the response to chemotherapy, the tumour aggressiveness and its ability to develop metastases. Inhibitors of mTOR and/or regulators of the balance RANKL/OPG are promising therapeutics. The study's expression of these new factors could be performed on the biopsy and will offer new therapeutic strategy.

YY1 overexpression is associated with poor prognosis and metastasis-free survival in patients suffering osteosarcoma

Background

The polycomb transcription factor Yin Yang 1 (YY1) overexpression can be causally implicated in experimental tumor growth and metastasization. To date, there is no clinical evidence of YY1 involvement in outcome of patients with osteosarcoma. Prognosis of osteosarcoma is still severe and only few patients survive beyond five years. We performed a prospective immunohistochemistry analysis to correlate YY1 immunostaining with metastatic development and survival in a selected homogeneous group of patients with osteosarcoma.

Methods

We studied 41 patients suffering from osteosarcoma (stage II-IVa). Multivariate analysis was performed using Cox proportional hazard regression to evaluate the correlation between YY1 expression and both metastasis development and mortality.

Results

YY1 protein is not usually present in normal bone; in contrast, a high number of patients (61%) showed a high score of YY1 positive cells (51-100%) and 39% had a low score (10-50% positive cells). No statistical difference was found in histology, anatomic sites, or response to chemotherapy between the two degrees of YY1 expression. Cox regression analysis demonstrated that the highest score of YY1 expression was predictive of both low metastasis-free survival (HR = 4.690, 95%CI = 1.079-20.396; p = 0.039) and poor overall survival (HR = 8.353, 95%CI = 1.863-37.451 p = 0.006) regardless of the effects of covariates such as age, gender, histology and chemonecrosis.

Conclusion

Overexpression of YY1 in primary site of osteosarcoma is associated with the occurrence of metastasis and poor clinical outcome.

Effects of transplantation sites on tumour growth, pulmonary metastasis and ezrin expression of canine osteosarcoma cell lines in nude mice

To determine the influence of the transplantation site of canine osteosarcoma (OS) cell lines on tumour growth and pulmonary metastasis, three OS cell lines were transplanted into nude mice via subcutaneous (SC), intratibial (IT) or intravenous (IV) injection. IT-xenografts exhibited greater potential for developing primary masses and pulmonary metastasis than SC-xenografts. In IT and IV xenografts, lung micrometastases along with phosphorylated ezrin-radixin-moesin (p-ERM) overexpression were found in mice xenografted with HMPOS and OOS cells after 1 week and metastasis was found with decreased p-ERM expression at later time points. The expression of ezrin and p-ERM in the primary tumours of IT-xenografted mice was higher than those in SC-xenografted mice with HMPOS and OOS cells. The results suggest that the orthotopic transplantation site plays an important role in the spontaneous metastasis of canine OS and that ezrin phosphorylation may be involved in the early metastatic mechanism of canine OS cells.

17β-Estradiol enhances breast cancer cell motility and invasion via extra-nuclear activation of actin-binding protein ezrin

Estrogen promotes breast cancer metastasis. However, the detailed mechanism remains largely unknown. The actin binding protein ezrin is a key component in tumor metastasis and its over-expression is positively correlated to the poor outcome of breast cancer. In this study, we investigate the effects of 17β-estradiol (E2) on the activation of ezrin and its role in estrogen-dependent breast cancer cell movement. In T47-D breast cancer cells, E2 rapidly enhances ezrin phosphorylation at Thr⁵⁶⁷ in a time- and concentration-dependent manner. The signalling cascade implicated in this action involves estrogen receptor (ER) interaction with the non-receptor tyrosine kinase c-Src, which activates the phosphatidylinositol-3 kinase/Akt pathway and the small GTPase RhoA/Rho-associated kinase (ROCK-2) complex. E2 enhances the horizontal cell migration and invasion of T47-D breast cancer cells in three-dimensional matrices, which is reversed by transfection of cells with specific ezrin siRNAs. In conclusion, E2 promotes breast cancer cell movement and invasion by the activation of ezrin. These results provide novel insights into the effects of estrogen on breast cancer progression and highlight potential targets to treat endocrine-sensitive breast cancers.

Potential transcriptional regulatory regions exist upstream of the human ezrin gene promoter in esophageal carcinoma cells

We previously demonstrated that the region -87/+134 of the human ezrin gene (VIL2) exhibited promoter activity in human esophageal carcinoma EC109 cells, and a further upstream region -1324/-890 positively regulated transcription. In this study, to identify the transcriptional regulatory regions upstream of the VIL2 promoter, we cloned VIL2 -1541/-706 segment containing the -1324/-890, and investigated its transcriptional regulatory properties via luciferase assays in transiently transfected cells. In EC109 cells, it was found that VIL2 -1541/-706 possessed promoter and enhancer activities. We also localized transcriptional regulatory regions by fusing 5'- or 3'-deletion segments of VIL2 -1541/-706 to a luciferase reporter. We found that there were three positive and one negative transcriptional regulatory regions within VIL2 -1541/-706 in EC109 cells. When these regions were separately located upstream of the luciferase gene without promoter, or located upstream of the VIL2 promoter or SV40 promoter directing the luciferase gene, only VIL2 -1297/-1186 exhibited considerable promoter and enhancer activities, which were lower than those of -1541/-706. In addition, transient expression of Sp1 increased ezrin expression and the transcriptional activation of VIL2 -1297/-1186. Other three regions, although exhibiting significantly positive or negative transcriptional regulation in deletion experiments, showed a weaker or absent regulation. These data suggested that more than one region upstream of the VIL2 promoter participated in VIL2 transcription, and the VIL2 -1297/-1186, probably as a key transcriptional regulatory region, regulated VIL2 transcription in company with other potential regulatory regions.

Role of the WWOX tumor suppressor gene in bone homeostasis and the pathogenesis of osteosarcoma

Osteosarcoma is the most common primary bone malignancy in children with unknown etiology and often with poor clinical outcome. In recent years, a critical role has emerged for the WW domain-containing oxidoreductase (WWOX) in osteosarcoma and bone biology. WWOX is a tumor suppressor that is deleted or attenuated in most human tumors. Wwox-deficient mice develop osteosarcoma and a bone metabolic disease characterized by hypocalcemia and osteopenia. Studies of human osteosarcomas have revealed that the WWOX gene is deleted in 30% of cases and WWOX protein is absent or reduced in ∼60% of tumors. Further, WWOX levels are attenuated in the majority of osteosarcoma cells, in which ectopic expression is associated with reduced proliferation, migration, invasion and tumorigenicity. At the molecular level, WWOX associates with RUNX2 and suppresses its transcriptional activity in osteoblasts and in cancer cells. This review provides new insights on the current knowledge of the spectrum of WWOX activities and future directions for the role of WWOX in bone biology and osteosarcoma.

Prognostic implication of ezrin expression in esophageal squamous cell carcinoma

BACKGROUND AND OBJECTIVES

Ezrin, a member of the ezrin-radixin-moesin family, was implicated in tumor progression, metastatic dissemination, and adverse outcomes in several cancer types, including esophageal squamous cell carcinoma (ESCC). The purpose of this study was to explore the clinical significance of ezrin expression in ESCC.

METHODS

Ezrin expression was detected on tissue microarrays of ESCC samples in 307 cases using immunohistochemical staining. Survival analysis was assessed by the Kaplan-Meier analysis. Relative risk was evaluated by the multivariate Cox proportional hazards model.

RESULTS

The staining pattern of ezrin was heterogeneous and varied from negative/weakly to intense expression in a cytoplasmic distribution. Kaplan-Meier survival analysis showed that ezrin expression was related to poor overall survival of ESCC patients (P=0.023). Further analysis revealed that ezrin expression was associated with the survival in the cases of stage III/IV (P=0.002); but did not influence the survival in the patients of stage I/II. Multivariate Cox analysis demonstrated that ezrin was an independent factor in prognosis of ESCC (P=0.011).

CONCLUSIONS

Ezrin might be a new molecular marker to predict the prognosis of ESCC patients.

Immunoexpression of Ezrin and CD44 in patients with osteosarcoma

BACKGROUND

Metastasis is an important prognostic factor among patients with osteosarcoma. It has been reported that ezrin is important in enabling metastasis and that CD44 expression leads to functional increases in ezrin activation.

OBJECTIVE

The aim of this study was to correlate ezrin and CD44 expression with prognosis.

SAMPLES AND METHODS

Patients with a diagnosis of osteosarcoma who had been treated at Hospital de Cancer de Barretos, Barretos, SP, Brazil, between 2000 and 2005 were selected from the Hospital Tumor Registry. Fifty-two patients and, among these, 34 surgical biopsy specimens of osteosarcoma before chemotherapy were reviewed by the Pathology Department. Ezrin and CD44H protein expression was evaluated using immunohistochemistry on the initial biopsy for these 34 samples.

RESULTS

Most patients (76%) were ezrin-positive in cytoplasm and membrane (38.2%); 58.9% presented high-intensity staining and 50.0% had high scores. Half of the patients were CD44H-positive, predominantly in cytoplasm (38.2%); 20.6% presented staining in more than 50% of the cells. None of the markers showed associations with any of the clinicopathologic variables studied. Among the ezrin-positive patients, the 5-year survival rate was 12.8%, whereas it was 41.7% among ezrin-negative patients (P=0.121). The interaction between ezrin and poor histologic response among nonmetastatic patients showed an association with relapse-free 5-year survival of 100% versus 12.7% (P=0.042). The overall survival rates for CD44-positive and negative patients were similar (21.5% and 25.3%, respectively) (P=0.676).

CONCLUSIONS

Neither CD44H nor ezrin immunoexpression could predict the prognosis for patients with osteosarcoma in our small sample.

Prognostic and predictive biomarkers of canine osteosarcoma

Canine osteosarcoma (OS) is an aggressive tumour that accounts for approximately 90% of primary bone tumours in the dog. Although the standard treatments (including limb amputation/sparing, chemotherapy and palliative radiotherapy) have significantly increased survival rates, almost 90% of animals will eventually develop predominantly pulmonary metastases. Despite advances in various therapies, prognosis remains poor, with median survival times ranging from 3 months to 1 year and <20% of dogs survive for >2 years following diagnosis. Various clinical and epidemiological markers have facilitated decision-making with respect to therapy but no single molecular biomarker has been shown to enhance prediction of disease progression. The publication of the canine genome in 2005 raised the possibility of increasing understanding of the genetic mechanisms underpinning canine OS. This review explores the use of biomarkers within the multi-disciplinary management of dogs with OS, and highlights the few known, potential prognostic/predictive molecular markers including their potential value as 'bridging biomarkers' for human OS. Although high-throughput profiling of canine OS remains in its infancy, research within the next decade using leading-edge screening technologies has the potential to identify biomarkers that may enhance diagnostic and prognostic accuracy and result in more effective, individually tailored, treatment and management protocols for affected dogs.