A novel role for ezrin in breast cancer angio/lymphangiogenesis

VEGFD signaling balances stability and activity-dependent structural plasticity of dendrites

Mature neurons have stable dendritic architecture, which is essential for the nervous system to operate correctly. The ability to undergo structural plasticity, required to support adaptive processes like memory formation, is still present in mature neurons. It is unclear what molecular and cellular processes control this delicate balance between dendritic structural plasticity and stabilization. Failures in the preservation of optimal dendrite structure due to atrophy or maladaptive plasticity result in abnormal connectivity and are associated with various neurological diseases. Vascular endothelial growth factor D (VEGFD) is critical for the maintenance of mature dendritic trees. Here, we describe how VEGFD affects the neuronal cytoskeleton and demonstrate that VEGFD exerts its effects on dendrite stabilization by influencing the actin cortex and reducing microtubule dynamics. Further, we found that during synaptic activity-induced structural plasticity VEGFD is downregulated. Our findings revealed that VEGFD, acting on its cognate receptor VEGFR3, opposes structural changes by negatively regulating dendrite growth in cultured hippocampal neurons and in vivo in the adult mouse hippocampus with consequences on memory formation. A phosphoproteomic screening identified several regulatory proteins of the cytoskeleton modulated by VEGFD. Among the actin cortex-associated proteins, we found that VEGFD induces dephosphorylation of ezrin at tyrosine 478 via activation of the striatal-enriched protein tyrosine phosphatase (STEP). Activity-triggered structural plasticity of dendrites was impaired by expression of a phospho-deficient mutant ezrin in vitro and in vivo. Thus, VEGFD governs the equilibrium between stabilization and plasticity of dendrites by acting as a molecular brake of structural remodeling.

Lymph node metastases in breast cancer: Mechanisms and molecular imaging

Breast cancer is the most common malignant disease of women in the world. Breast cancer often metastasizes to axillary lymph nodes. Accurate assessment of the status of axillary lymph nodes is crucial to the staging and treatment of breast cancer. None of the methods used clinically for preoperative noninvasive examination of axillary lymph nodes can accurately identify cancer cells from a molecular level. In recent years, with the in-depth study of lymph node metastases, the mechanisms and molecular imaging of lymph node metastases in breast cancer have been reported. In this review, we highlight the new progress in the study of the main mechanisms of lymph node metastases in breast cancer. In addition, we analyze the advantages and disadvantages of traditional preoperative axillary lymph node imaging methods for breast cancer, and list molecular imaging methods that can accurately identify breast cancer cells in lymph nodes.

Polarization of Cancer-Associated Macrophages Maneuver Neoplastic Attributes of Pancreatic Ductal Adenocarcinoma

Mounting evidence links the phenomenon of enhanced recruitment of tumor-associated macrophages towards cancer bulks to neoplastic growth, invasion, metastasis, immune escape, matrix remodeling, and therapeutic resistance. In the context of cancer progression, naïve macrophages are polarized into M1 or M2 subtypes according to their differentiation status, gene signatures, and functional roles. While the former render proinflammatory and anticancer effects, the latter subpopulation elicits an opposite impact on pancreatic ductal adenocarcinoma. M2 macrophages have gained increasing attention as they are largely responsible for molding an immune-suppressive landscape. Through positive feedback circuits involving a paracrine manner, M2 macrophages can be amplified by and synergized with neighboring neoplastic cells, fibroblasts, endothelial cells, and non-cell autonomous constituents in the microenvironmental niche to promote an advanced disease state. This review delineates the molecular cues expanding M2 populations that subsequently convey notorious clinical outcomes. Future therapeutic regimens shall comprise protocols attempting to abolish environmental niches favoring M2 polarization; weaken cancer growth typically assisted by M2; promote the recruitment of tumoricidal CD8⁺ T lymphocytes and dendritic cells; and boost susceptibility towards gemcitabine as well as other chemotherapeutic agents.

Ezrin accelerates breast cancer liver metastasis through promoting furin-like convertase-mediated cleavage of Notch1

BACKGROUND

Ezrin, known as a crosslinker between the plasma membrane and actin cytoskeleton, is closely associated with breast cancer (BC) progression. Here, we explored a novel role of ezrin in breast cancer liver metastasis (BCLM).

METHODS

The clinical relevance of ezrin was evaluated using in silico tools and confirmed in BC specimens. The effect of ezrin on proliferation, migration and invasion was examined in vitro and in vivo using murine primary liver-metastatic breast cancer cells (mLM). The molecular mechanism involved in ezrin-mediated activation of the Notch1 signaling pathway was elucidated using in vitro models.

RESULTS

Data-mining demonstrated that ezrin mRNA and protein expression is up-regulated in breast cancer cohorts and has prognostic significance. Ezrin overexpression promotes cell proliferation, migration and invasion in vitro and in vivo. Hairy and enhancer of split-1 (Hes1) is one of the most significantly enriched candidates of differentially expressed genes in ezrin overexpression and control mLM cells. Ezrin can positively regulate Hes1 mRNA and protein expression, and their coexpression was associated with poor prognosis in BC patients. Ezrin promoted BC cell proliferation in a Hes1-dependent manner without directly interacting with Hes1. The functional link between ezrin and Hes1 is dependent on Notch1 activation through promotion of furin-like convertase cleavage.

CONCLUSION

Our results demonstrated that ezrin drives BCLM through activation of the Notch signaling pathway via furin-like convertase. These findings provide a better understanding of the mechanism of ezrin in breast cancer progression, with the goal of discovering a novel target for the treatment of BCLM in the future.

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.

Targeting the Ezrin Adaptor Protein Sensitizes Metastatic Breast Cancer Cells to Chemotherapy and Reduces Neoadjuvant Therapy-induced Metastasis

The main cause of cancer-associated deaths is the spread of cancer cells to distant organs. Despite its success in the primary tumor setting, modern chemotherapeutic strategies are rendered ineffective at treating metastatic disease, largely due to the development of resistance. The adaptor protein ezrin has been shown to promote cancer metastasis in multiple preclinical models and is associated with poor prognosis in several cancer types, including breast cancer. Ezrin promotes pro-survival signaling, particularly in disseminated cancer cells, to facilitate metastatic outgrowth. However, the role of ezrin in breast cancer chemoresistance is not fully known. In this study, we show that upregulating or downregulating ezrin expression modifies the sensitivity of breast cancer cells to doxorubicin and docetaxel treatment in vitro and is associated with changes in PI3K/Akt and NFκB pathway activation. In addition, we tested the effects of systemic treatment with a small-molecule ezrin inhibitor, NSC668394, on lung metastatic burden in vivo as a monotherapy, or in combination with anthracycline- or taxane-based chemotherapy treatment. We show that anti-ezrin treatment alone reduces metastatic burden and markedly sensitizes metastases to doxorubicin or docetaxel in neoadjuvant as well as neoadjuvant plus adjuvant treatment models. Taken together, our findings demonstrate the impact of anti-ezrin treatment in modulating response to chemotherapy in breast cancer cells as well as the efficacy of anti-ezrin treatment in combination with chemotherapy at reducing metastatic burden.

Significance

This work provides preclinical evidence for combining anti-ezrin treatment with chemotherapy as a novel strategy for effectively targeting metastasis, particularly in a neoadjuvant treatment setting.

Investigation of the effects of overexpression of jumping translocation breakpoint (JTB) protein in MCF7 cells for potential use as a biomarker in breast cancer

Jumping translocation breakpoint (JTB) gene acts as a tumor suppressor or an oncogene in different malignancies, including breast cancer (BC), where it was reported as overexpressed. However, the molecular functions, biological processes and underlying mechanisms through which JTB protein causes increased cell growth, proliferation and invasion is still not fully deciphered. Our goal is to identify the functions of JTB protein by cellular proteomics approaches. MCF7 breast cancer cells were transfected with sense orientation of hJTB cDNA in HA, His and FLAG tagged CMV expression vector to overexpress hJTB and the expression levels were confirmed by Western blotting (WB). Proteins extracted from transfected cells were separated by SDS-PAGE and the in-gel digested peptides were analyzed by nano-liquid chromatography tandem mass spectrometry (nanoLC-MS/MS). By comparing the proteome of cells with upregulated conditions of JTB vs control and identifying the protein dysregulation patterns, we aim to understand the function of this protein and its contribution to tumorigenesis. Gene Set Enrichment Analysis (GSEA) algorithm was performed to investigate the biological processes and pathways that are associated with the JTB protein upregulation. The results demonstrated four significantly enriched gene sets from the following significantly upregulated pathways: mitotic spindle assembly, estrogen response late, epithelial-to-mesenchymal transition (EMT) and estrogen response early. JTB protein itself is involved in mitotic spindle pathway by its role in cell division/cytokinesis, and within estrogen response early and late pathways, contributing to discrimination between luminal and mesenchymal breast cancer. Thus, the overexpressed JTB condition was significantly associated with an increased expression of ACTNs, FLNA, FLNB, EZR, MYOF, COL3A1, COL11A1, HSPA1A, HSP90A, WDR, EPPK1, FASN and FOXA1 proteins related to deregulation of cytoskeletal organization and biogenesis, mitotic spindle organization, ECM remodeling, cellular response to estrogen, proliferation, migration, metastasis, increased lipid biogenesis, endocrine therapy resistance, antiapoptosis and discrimination between different breast cancer subtypes. Other upregulated proteins for overexpressed JTB condition are involved in multiple cellular functions and pathways that become dysregulated, such as tumor microenvironment (TME) acidification, the transmembrane transport pathways, glycolytic flux, iron metabolism and oxidative stress, metabolic reprogramming, nucleocytosolic mRNA transport, transcriptional activation, chromatin remodeling, modulation of cell death pathways, stress responsive pathways, and cancer drug resistance. The downregulated proteins for overexpressed JTB condition are involved in adaptive communication between external and internal environment of cells and maintenance between pro-apoptotic and anti-apoptotic signaling pathways, vesicle trafficking and secretion, DNA lesions repair and suppression of genes involved in tumor progression, proteostasis, redox state regulation, biosynthesis of macromolecules, lipolytic pathway, carbohydrate metabolism, dysregulation of ubiquitin-mediated degradation system, cancer cell immune escape, cell-to-cell and cell-to-ECM interactions, and cytoskeletal behaviour. There were no significantly enriched downregulated pathways.

Ezrin and Radixin Differentially Modulate Cell Surface Expression of Programmed Death Ligand-1 in Human Pancreatic Ductal Adenocarcinoma KP-2 Cells

Immune checkpoint blockade (ICB) therapies, such as immune checkpoint inhibitors against programmed death ligand-1 (PD-L1), have not been successful in treating patients with pancreatic ductal adenocarcinoma (PDAC). Despite the critical role of PD-L1 in various types of cancers, the regulatory mechanism of PD-L1 expression on the cell surface of PDAC is poorly understood. Therefore, uncovering potential modulators of cell surface localisation of PD-L1 may provide a new strategy to improve ICB therapy in patients with PDAC. Here, we examined the role of ezrin/radixin/moesin (ERM) family scaffold proteins that crosslink transmembrane proteins with the actin cytoskeleton in the surface localisation of PD-L1 in KP-2 cells, a human PDAC cell line. Our results demonstrated the abundant protein expression of PD-L1, ezrin, and radixin, but not moesin, as well as their colocalisation in the plasma membrane. Interestingly, immunoprecipitation analysis detected the molecular interaction of PD-L1 with ezrin and radixin. Moreover, gene silencing of ezrin moderately decreased the mRNA and cell surface expression of PD-L1, while that of radixin greatly decreased the surface expression of PD-L1 without altering the mRNA levels. Thus, radixin and ezrin differentially modulate the cell surface localisation of PD-L1 in KP-2 cells, highlighting a potential therapeutic target to improve the current ICB therapy in PDAC.

Cytoskeletal Remodeling in Cancer

Simple Summary

Cell migration is an essential process from embryogenesis to cell death. This is tightly regulated by numerous proteins that help in proper functioning of the cell. In diseases like cancer, this process is deregulated and helps in the dissemination of tumor cells from the primary site to secondary sites initiating the process of metastasis. For metastasis to be efficient, cytoskeletal components like actin, myosin, and intermediate filaments and their associated proteins should co-ordinate in an orderly fashion leading to the formation of many cellular protrusions-like lamellipodia and filopodia and invadopodia. Knowledge of this process is the key to control metastasis of cancer cells that leads to death in 90% of the patients. The focus of this review is giving an overall understanding of these process, concentrating on the changes in protein association and regulation and how the tumor cells use it to their advantage. Since the expression of cytoskeletal proteins can be directly related to the degree of malignancy, knowledge about these proteins will provide powerful tools to improve both cancer prognosis and treatment.

Abstract

Successful metastasis depends on cell invasion, migration, host immune escape, extravasation, and angiogenesis. The process of cell invasion and migration relies on the dynamic changes taking place in the cytoskeletal components; actin, tubulin and intermediate filaments. This is possible due to the plasticity of the cytoskeleton and coordinated action of all the three, is crucial for the process of metastasis from the primary site. Changes in cellular architecture by internal clues will affect the cell functions leading to the formation of different protrusions like lamellipodia, filopodia, and invadopodia that help in cell migration eventually leading to metastasis, which is life threatening than the formation of neoplasms. Understanding the signaling mechanisms involved, will give a better insight of the changes during metastasis, which will eventually help targeting proteins for treatment resulting in reduced mortality and longer survival.

Bidirectional Tumor-Promoting Activities of Macrophage Ezrin

Ezrin links the cytoskeleton to cell surface integrins and plasma membrane receptors, contributing to the proliferative and metastatic potential of cancer cells. Elevated ezrin expression in several cancers is associated with poor outcomes. Tumor cell ezrin expression and function have been investigated in depth; however, its role in macrophages and other tumor microenvironment cells remains unexplored. Macrophages profoundly influence tumorigenesis, and here we explore ezrin’s influence on tumor-promoting macrophage functions. Ezrin knockdown in THP-1 macrophages reveals its important contribution to adhesion to endothelial cells. Unexpectedly, ezrin is essential for the basal and breast cancer cell-stimulated THP-1 expression of ITGAM mRNA that encodes integrin CD11b, critical for cell adhesion. Ezrin skews the differentiation of THP-1 macrophages towards the pro-tumorigenic, M2 subtype, as shown by the reduced expression of FN1, IL10, and CCL22 mRNAs following ezrin knockdown. Additionally, macrophage ezrin contributes to the secretion of factors that stimulate tumor cell migration, invasion, and clonogenic growth. Lastly, THP-1 ezrin is critical for the expression of mRNAs encoding vascular endothelial growth factor (VEGF)-A and matrix metalloproteinase (MMP)-9, consistent with pro-tumorigenic function. Collectively, our results provide insight into ezrin’s role in tumorigenesis, revealing a bidirectional interaction between tumor-associated macrophages and tumor cells, and suggest myeloid cell ezrin as a target for therapeutic intervention against cancer.

An epigenetic increase in mitochondrial fission by MiD49 and MiD51 regulates the cell cycle in cancer: Diagnostic and therapeutic implications

Excessive proliferation and apoptosis-resistance are hallmarks of cancer. Increased dynamin-related protein 1 (Drp1)-mediated mitochondrial fission is one of the mediators of this phenotype. Mitochondrial fission that accompanies the nuclear division is called mitotic fission and occurs when activated Drp1 binds partner proteins on the outer mitochondrial membrane. We examine the role of Drp1-binding partners, mitochondrial dynamics protein of 49 and 51 kDa (MiD49 and MiD51), as drivers of cell proliferation and apoptosis-resistance in non-small cell lung cancer (NSCLC) and invasive breast carcinoma (IBC). We also evaluate whether inhibiting MiDs can be therapeutically exploited to regress cancer. We show that MiD levels are pathologically elevated in NSCLC and IBC by an epigenetic mechanism (decreased microRNA-34a-3p expression). MiDs silencing causes cell cycle arrest through (a) increased expression of cell cycle inhibitors, p27^Kip1 and p21^Waf1 , (b) inhibition of Drp1, and (c) inhibition of the Akt-mTOR-p70S6K pathway. Silencing MiDs leads to mitochondrial fusion, cell cycle arrest, increased apoptosis, and tumor regression in a xenotransplant NSCLC model. There are positive correlations between MiD expression and tumor size and grade in breast cancer patients and inverse correlations with survival in NSCLC patients. The microRNA-34a-3p-MiDs axis is important to cancer pathogenesis and constitutes a new therapeutic target.

Advanced glycation end products induce immature angiogenesis in in vivo and ex vivo mouse models

Proliferative diabetic retinopathy (PDR) is a progressive disease predominantly involving pathological angiogenesis and is characterized by the development of immature, fragile, and easily hemorrhagic new vessels. Advanced glycation end products (AGEs) and the receptor for AGEs (RAGE) play important roles in the progression of diabetic retinopathy. Our previous studies demonstrated that AGEs promoted HUVEC angiogenesis by inducing moesin phosphorylation via RhoA/Rho-associated protein kinase (ROCK) pathway. The aim of this study was to further confirm AGE-induced angiogenesis in vivo and the involvement of RAGE, ROCK, and moesin phosphorylation in this process. We performed the study in an AGE-treated mouse model with various angiogenesis assays in multiple in vivo and ex vivo models. The results demonstrated that AGEs promoted significant neovascularization in whole mount retina and mouse aortic ring of adult and postnatal mice and in Matrigel plug as well, which were consistently accompanied by increased moesin phosphorylation. The increase of AGE-evoked neovascularization and moesin phosphorylation were both attenuated by RAGE knockout or ROCK inhibitor Y27632 administration in mice. We also revealed the pathological characteristics of AGE-promoted angiogenesis by demonstrating the decrease of pericyte coverage and the disarranged endothelial alignment in microvessels. In conclusion, this study provides in vivo evidences that AGEs induce immature angiogenesis by binding to RAGE, activating the RhoA/ROCK signal pathway and inducing moesin phosphorylation.NEW & NOTEWORTHY Advanced glycation end product (AGE)-induced formation of neovessels and phosphorylation of moesin in retina and aortic ring required AGE receptors. AGEs increased neovessels and the phosphorylation of moesin in retina and aortic ring via RhoA/ROCK pathway. AGE-induced immature angiogenesis in AGE-treated mouse retina and aortic ring. The AGE-RAGE axis and moesin could be candidate targets for overcoming relative diseases.

Pancreatic cancer-derived small extracellular vesical Ezrin regulates macrophage polarization and promotes metastasis

Small extracellular vesicles (sEVs) mediate the interaction between tumor and tumor-associated macrophages (TAMs). This study aims to demonstrate that the pancreatic ductal adenocarcinoma (PDAC)-derived sEV Ezrin (sEV-EZR) could modulate macrophage polarization and promote PDAC metastasis. We isolated PDAC-derived sEVs and plasma sEVs from PDAC patients. Human blood mononuclear cell (PBMC)-derived macrophages were treated with PDAC-derived sEVs or the counterpart depleted Ezrin (EZR) with shRNA-mediated knockdown. We used enzyme-linked immunosorbent assays and flow cytometry to monitor macrophages polarization. NOD/SCID/IL2Rγ^null mice were treated with sEVs to study PDAC liver metastasis. The plasma sEV-EZR levels of 165 PDAC patients and 151 high-risk controls were analyzed. The EZR levels are higher in sEVs derived from PDAC cells and PDAC-patient plasma than that of the normal controls. PDAC-derived sEVs modulate the polarization of macrophages to M2 phenotype, while PDAC-shEZR-derived sEVs polarize macrophages into M1 phenotype. We found an increase in M1 TAMs and a decrease in M2 TAMs in orthotropic tumors treated with PDAC-shEZR-derived sEVs. The amount of liver metastasis in PDAC-shEZR-derived sEVs-treated mice was observed to be smaller than that of controls. The mean plasma sEV-EZR levels from PDAC patients were significantly higher than those from the controls (32.43±20.78 vs. 21.88±11.43 pg/ml; P<0.0001). The overall survival in the high-plasma sEV-EZR patients was significantly shorter than that in the low-EZR group (6.94±15.25 vs. 9.63±15.11 months; P=0.0418). sEV-EZR could modulate macrophage polarization and promote metastasis in PDAC. Targeting sEV-EZR can be considered a promising therapeutic strategy to inhibit PDAC metastasis.

miR-205-3p promotes proliferation and reduces apoptosis of breast cancer MCF-7 cells and is associated with poor prognosis of breast cancer patients

Background

To study the expression of microribonucleic acid (miR)‐205 in breast cancer and its effects on the proliferation and apoptosis of breast cancer cells.

Methods

Breast cancer cell line MCF‐7 cells with stable expression of miR‐205‐3p were constructed. Cell proliferation, invasion, and apoptosis were detected via MTT assay, transwell assay, and flow cytometry, respectively. The expressions of Ezrin, LaminA/C, cleaved caspase‐3, Bcl‐2, and Bax were detected via Western blotting. The expressions of miR‐205‐3p in breast cancer tissues and para‐carcinoma tissues were detected via quantitative PCR (qPCR).

Results

In transfection group, cell proliferation and invasion capacities were increased significantly (P < 0.01), but apoptotic cells were significantly reduced (P < 0.01). In addition, the expressions of Ezrin, LaminA/C, and cleaved caspase‐3 in the transfection group were significantly decreased (P < 0.01), but the Bcl‐2/Bax ratio was significantly increased (P < 0.01). The miR‐205‐3p expression in tumor tissues of breast cancer patients was significantly higher than that in para‐carcinoma tissue, but Ezrin, LaminA/C, and cleaved caspase‐3 expressions in tumor tissues were remarkably declined (P < 0.01), while the Bcl‐2/Bax ratio was remarkably increased (P < 0.01). Moreover, the 5‐year survival of patients with high expression of miR‐205‐3p was significantly shorter than patients with normal or low expression (P < 0.01).

Conclusion

Highly expressed miR‐205‐3p can promote the proliferation and invasion and reduce the apoptosis of breast cancer cells, and the high expression of miR‐205‐3p can significantly reduce the survival time of patients.

Establishment and Characterization of a New Triple Negative Breast Cancer Cell Line from an Iranian Breast Cancer Tissue

Breast cancer is the most common malignancy and the leading cause of cancer-related death among women worldwide. The underlying mechanisms for breast cancer development, especially in young women, are not completely understood. Although there are several experimental models to understand the biology of breast cancer such as immortalized cell lines, many of these cell lines have been in culture for decades and most of them have been derived from Caucasians or African-Americans. So, it is required to establish a new cell line derived from primary tumors and Asian women. In this study Pari-Institute for Cancer Research (Pari-ICR) was derived from the primary breast tumor of a 36-years old patient with invasive ductal carcinoma. We characterized the cell line by examining morphology, expression of different markers, and functional profile. Immunocytochemistry showed that this cell line does not express estrogen and progesterone receptors as well as human epidermal growth factor receptor 2 (HER2). Pari-ICR cell line expresses high levels of Vimentin, Ezrin, and S100 but does not express EpCAM, Cytokeratin19, Pan-cytokeratin, Nestin, and Desmin. Its doubling time of Pari-ICR was about 22h and was able to grow as colonies in soft agar. It displayed a higher ability of migration and invasion in comparison with MCF-7 cell line. This breast cancer cell line can serve as a model for understanding the molecular mechanisms of breast carcinogenesis. Moreover, it can be used as an appropriate resource to find novel biomarkers or assess new drugs.

IgG based immunome analyses of breast cancer patients reveal underlying signaling pathways

Background: Breast cancer is the most frequent and one of the most fatal malignancies among women. Within the concept of personalized medicine, molecular characterization of tumors is usually performed by analyzing somatic mutations, RNA gene expression signatures or the proteome by mass-spectrometry. Alternatively, the immunological fingerprint of the patients can be analyzed by protein microarrays, which is able to provide another layer of molecular pathological information without invasive intervention.

Results: We have investigated the immune signature of breast cancer patients and compared them with healthy controls, using protein microarray-based IgG profiling. The identified differentially reactive antigens (n=517) were further evaluated by means of various pathway analysis tools. Our results indicate that the immune signature of breast cancer patients shows a clear distinction from healthy individuals characterized by differentially reactive antigens involved in known disease relevant signaling pathways, such as VEGF, AKT/PI3K/mTOR or c-KIT, which is in close agreement with the findings from RNA-based expression profiles.

Conclusion: Differential antigenic properties between breast cancer patients and healthy individual classes can be defined by serum-IgG profiling on protein microarrays. These immunome profiles provide an additional layer of molecular pathological information, which has the potential to refine and complete the systems biological map of neoplastic disease.

Lymphatic changes in cancer and drug delivery to the lymphatics in solid tumors

Although many solid tumors use the lymphatic system to metastasize, there are few treatment options that directly target cancer present in the lymphatic system, and those that do are highly invasive, uncomfortable, and/or have limitations. In this review we provide a brief overview of lymphatic function and anatomy, discusses changes that befall the lymphatics in cancer and the mechanisms by which these changes occur, and highlight limitations of lymphatic drug delivery. We then go on to summarize relevant techniques and new research for targeting cancer populations in the lymphatics and enhancing drug delivery intralymphatically, including intralymphatic injections, isolated limb perfusion, passive nano drug delivery systems, and actively targeted nanomedicine.

Ezrin promotes breast cancer progression by modulating AKT signals

Background

Ezrin, which is known as a cytoskeleton linker protein, is closely linked with the metastatic progression of cancer and is frequently abnormally expressed in aggressive cancer types. However, the possible involvement of Ezrin in metastasis and angiogenesis in breast cancer remains unclear.

Methods

Immunohistochemical analysis of Ezrin was performed on both BC samples (n = 117) and normal epithelium samples (n = 47). In vivo and in vitro assays were performed to validate the effect of Ezrin on AKT pathway-mediated BC progression.

Results

In this study, Ezrin was found to be upregulated in BC tissues, which was linked with aggressive tumour characteristics and poor prognosis. Moreover, we showed that Ezrin promotes BC proliferation, migration, invasion, and angiogenesis in vitro and in vivo. Mechanistic analysis showed that Ezrin interacted with AKT, and promoted its kinase activity, thereby regulating the AKT pathway in BC.

Conclusions

In all, we propose a model for an Ezrin/AKT oncoprotein axis, which provides novel insight into how Ezrin contributes to BC progression.

Intravital imaging reveals systemic ezrin inhibition impedes cancer cell migration and lymph node metastasis in breast cancer

Background

Limited understanding of the cancer biology of metastatic sites is a major factor contributing to poor outcomes in cancer patients. The regional lymph nodes are the most common site of metastasis in most solid cancers and their involvement is a strong predictor of relapse in breast cancer (BC). We have previously shown that ezrin, a cytoskeletal–membrane linker protein, is associated with lymphovascular invasion and promotes metastatic progression in BC. However, the efficacy of pharmacological inhibition of ezrin in blocking cancer cell migration and metastasis remains unexplored in BC.

Methods

We quantified ezrin expression in a BC tissue microarray (n = 347) to assess its correlation with risk of relapse. Next, we developed a quantitative intravital microscopy (qIVM) approach, using a syngeneic lymphatic reporter mouse tumor model, to investigate the effect of systemic ezrin inhibition on cancer cell migration and metastasis.

Results

We show that ezrin is expressed at significantly higher levels in lymph node metastases compared to matched primary tumors, and that a high tumor ezrin level is associated with increased risk of relapse in BC patients with regional disease. Using qIVM, we observe a subset of cancer cells that retain their invasive and migratory phenotype at the tumor-draining lymph node. We further show that systemic inhibition of ezrin, using a small molecule compound (NSC668394), impedes the migration of cancer cells in vivo. Furthermore, systemic ezrin inhibition leads to reductions in metastatic burden at the distal axillary lymph node and lungs.

Conclusions

Our findings demonstrate that the tumor ezrin level act as an independent biomarker in predicting relapse and provide a rationale for therapeutic targeting of ezrin to reduce the metastatic capacity of cancer cells in high-risk BC patients with elevated ezrin expression.

Electronic supplementary material

The online version of this article (10.1186/s13058-018-1079-7) contains supplementary material, which is available to authorized users.

Upregulation of miR-183-5p is responsible for the promotion of apoptosis and inhibition of the epithelial-mesenchymal transition, proliferation, invasion and migration of human endometrial cancer cells by downregulating Ezrin

Endometrial cancer is a life‑threatening malignancy that affects women all over the world, and it has an increasing incidence. MicroRNAs (miRNAs/miRs) have been reported to be involved in cellular activities in endometrial cancer. The present study aimed to examine the effects of miR‑183‑5p on the epithelial‑mesenchymal transition (EMT), proliferation, invasion, migration and apoptosis of human endometrial cancer cells by targeting Ezrin. Primary endometrial cancer tissues and adjacent normal tissues were obtained for the investigation. The protein expression of Ezrin in tissues was detected by immunohistochemistry. The expression level of miR‑183‑5p and the mRNA and protein expression levels of Ezrin and EMT‑associated genes were determined by reverse transcription‑quantitative polymerase chain reaction and western blot analyses. Endometrial cancer cells were treated with miR‑183‑5p inhibitors, small interfering RNA targeting Ezrin or miR‑183‑5p inhibitors. Cell proliferation, cell cycle, apoptosis, migration and invasion were then evaluated using an MTT assay, flow cytometry, scratch test and Transwell assay, respectively. Compared with normal adjacent tissues, the expression of miR‑183‑5p was decreased in endometrial cancer tissues, and the expression of Ezrin was significantly increased in endometrial cancer tissues. The protein expression of Ezrin was correlated with the severity and poor prognosis of endometrial cancer. Notably, the target prediction program and the luciferase reporter gene assay confirmed that miR‑183‑5p targeted and negatively regulated the expression of Ezrin. In vivo experiments revealed that the increased expression of miR‑183‑5p and decreased expression of Ezrin inhibited EMT, cell proliferation, migration and invasion, but promoted cell apoptosis in Ishikawa cells. These results suggested that the upregulated expression of miR‑183‑5p promoted apoptosis and suppressed the EMT, proliferation, invasion and migration of human endometrial cancer cells by downregulating Ezrin.

Combination of SIRT1 and Src overexpression suggests poor prognosis in luminal breast cancer

Objectives

1) Analyze the correlation of SIRT1 and Src with human breast cancer (BC) prognosis; 2) explore the roles of SIRT1 and Src in BC cell proliferation, tumor invasion, and metastasis; and 3) analyze the correlation and interaction between SIRT1 and Src.

Materials and methods

1) Tissue microarray was used to analyze the expression of SIRT1 and Src in human BC tissues and the correlation between protein expression and cancer prognosis; 2) CCK8 assay was used to determine the influence of SIRT1 and Src inhibitors on BC cell proliferation; 3) Transwell migration assay and wound healing assay were used to determine the effect of SIRT1 and Src inhibitors on BC cell migration and invasion; and 4) Western blotting was used to analyze the correlation and interaction between SIRT1 and Src.

Results

1) Combination of SIRT1 and/or Src positivity is a prognosis factor in BC, especially in luminal type; 2) MCF-7 cell proliferation is suppressed by SIRT1 inhibitor Ex527, and cell migration and invasion were inhibited by Src inhibitor bosutinib; 3) combined with Ex527, bosutinib has a significantly increased effect on MCF-7 cell migration suppression; and 4) there is a positive association between SIRT1 and Src both in BC tissues and in MCF-7 cells.

Conclusion

1) SIRT1 and Src overexpression are both correlated with poor prognosis in human BC; 2) SIRT1 + Src (SIRT1 and/or Src positivity) is a fine prognosis model for luminal-type BC; 3) SIRT1 is a copromotor of Src in BC migration and invasion, but not in cell proliferation; and 4) our results suggest a potential interaction or a common regulation pathway between SIRT1 and Src expression and activity.

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.

Ezrin contributes to cervical cancer progression through induction of epithelial-mesenchymal transition

Cervical cancer is the third most common cancer in females worldwide. The treatment options for advanced cervical cancer are limited, leading to high mortality. Ezrin is a membrane-cytoskeleton-binding protein recently reported to act as a tumor promoter, and we previously indicated that the aberrant localization and overexpression of Ezrin could be an independent effective biomarker for prognostic evaluation of cervical cancers. In this study, we identified Ezrin as a regulator of epithelial-mesenchymal transition (EMT) and metastasis in cervical cancer. Ezrin knock-down inhibited anchorage-independent growth, cell migration, and invasion of cervical cancer cell lines in vitro and in vivo. EMT was inhibited in Ezrin-depleted cells, with up-regulation of E-cadherin and Cytokeratin-18 (CK-18) and down-regulation of mesenchymal markers. Ezrin knock-down also induced Akt phosphorylation. These results implicate Ezrin as an EMT regulator and tumor promoter in cervical cancer, and down-regulation of Ezrin suppressed cervical cancer progression, possibly via the phosphoinositide 3-kinase/Akt pathway. Furthermore, the expression pattern of Ezrin protein was closely related with the lymphovascular invasion status of cervical cancer by immunohistochemistry, and the survival analysis revealed that the cervical cancer patients with the perinuclear Ezrin expression pattern had longer survival time than those with the cytoplasmic Ezrin expression pattern. Ezrin thus represents a promising target for the development of novel and effective strategies aimed at preventing the progression of cervical cancer.

Ezrin as a possible diagnostic and/or prognostic biomarker in mice lymphatic metastatic hepatocellular carcinoma in vivo

Hepatocellular carcinoma (HCC) ranks in the top of cancers leading to death. Early diagnosis is the big challenge in the case of HCC. Our in vitro study showed that Ezrin expression in lymphatic metastasis hepatocellular carcinoma (LNM-HCC) was associated with the metastatic rate. Here we aim to evaluate Ezrin expression as diagnostic and/or prognostic biomarker of LNM-HCC in mice. Chinese inbred 615 mice, Hca-F and Hca-P cell lines were used in the study. Histological changes were determined by Hematoxylin and Eosin, while Ezrin expression was assessed by qRT-PCR, western blot, immunohistochemistry, and enzyme-linked immunosorbent assay. Ezrin expression in this study gives credit to our in vitro study which Ezrin expression was positively correlated with LNM-HCC and negatively with Annexin7 (A7) expression. The highest histological changes were observed in high metastatic primary/secondary tumors combined with high Ezrin expression. Ezrin and A7 are higher in total primary tumors than in total secondary tumors (P = 0.0001, P = 0.021), respectively. Ezrin expression was enhanced in Hca-P A7 down-regulated primary/secondary tumors (P = 0.004), whereas, Ezrin expression was suppressed in Hca-F A7 upregulated primary/secondary tumors. Serum ELISA indicated differential expression of Ezrin among the study groups (P ≤ 0.0001). Ezrin expression was higher in NC-Hca-F than NC-Hca-P (P ≤ 0.0001), suppressed in Hca-F A7 upregulation (P ≤ 0.0001) and in enhanced in Hca-P A7 down-regulation (P = 0.0001). In conclusion, Ezrin level may serve as a differential diagnostic and/or prognostic biomarker for high and low LNM-HCC and may be beneficial in the diagnosis of HCC disease. © 2017 BioFactors, 43(5):662-672, 2017.

Expression of ezrin and moesin in primary breast carcinoma and matched lymph node metastases

Ezrin, radixin, moesin (ERM) are important membrane-cytoskeletal crosslinkers and are suggested to play important role in cancer progression and metastasis. Even though ERM proteins were generally considered to be functionally redundant and the most studied was ezrin, recent studies highlight their distinct roles in metastatic process. Little information is available regarding the role of individual ERM proteins and their phosphorylated forms in human breast cancer. Our study is the first to examine expression of ezrin, moesin and their phosphorylated forms in primary breast tumors and matched lymph node metastases (LNMs) and their correlation with clinicopathological variables. A total of 88 primary breast cancer, 91 LNMs, 54 intraductal carcinoma and 26 normal adjacent breast tissue samples from tissue microarrays were studied. Expression was determined by immunohistochemistry, the intensity and number of positive cells was scored. Statistical analysis of protein expression and patients' age, tumor grade and hormonal status was performed. No statistical significant difference was found in ezrin, moesin, p-ezrinTyr353 and pan-p-ezrinThr567/radixinThr564/moesinThr558 expression between primary tumors and LNMs. Even though it was not significant, moesin expression varied between primary tumors, intraductal carcinoma, normal breast adjacent tissue and LNMs. A significant positive correlation between moesin and tumor grade has been proven. Even though primary tumors and matched LNMs did not show different expression patterns, moesin correlated significantly with higher tumor grade. Its positivity in intraductal carcinoma and normal breast tissue adjacent to cancer might indicate its role in tumor intiation/progression.

Ezrin/NF-kB activation regulates epithelial- mesenchymal transition induced by EGF and promotes metastasis of colorectal cancer

There is growing evidence that epithelial mesenchymal-transition (EMT) plays significant roles in terms of tumor metastasis. There are a lot of cytokines inducing EMT of tumor cells, EGF is one of the important cytokines.Ezrin is a connexin between the cytoskeleton and the cell membrane, which is closely related to the morphological movement and metastasis of tumor cells.EGF can activate Ezrin and affects cell motility. In recent years, many studies have shown that NF-kB acts as an important transcription factor, involving in the process of EMT. However, does Ezrin participate in the regulation of EGF-induced EMT through the NF-kB pathway? This question needs us to discuss.In the present study, we found that EGF could induce colorectal cancer cells to develop EMT,enhance their ability to invade and migrate and promotes phosphorylation of Ezrin Tyr353.On the other hand, inhibition of Ezrin could reverse EGF-induced EMT and inhibit NF-kB P65 translocating into the nucleus. Finally, knockout of Ezrin inhibited EGF-induced lung metastasis of colorectal cancer xenografts and abnormal activation of Ezrin and NF-kB were related with colorectal cancer metastasis and poor prognosis. Our present results suggest that Ezrin/NF-kB pathway may provide experimental evidence for new targeted drugs for colorectal cancer metastasis.

Estrogen stimulated migration and invasion of estrogen receptor-negative breast cancer cells involves an ezrin-dependent crosstalk between G protein-coupled receptor 30 and estrogen receptor beta signaling

Estrogen mediates important cellular activities in estrogen receptor negative (ER-) breast cancer cells via membrane associated G protein-coupled receptor 30 (GPR30). However, the biological role and mechanism of estrogen action on cell motility and invasion in this aggressive kind of tumors remains poorly understood. We showed here that treatment with 17β-estradiol (E2) in ER-negative cancer cells resulted in ezrin-dependent cytoskeleton rearrangement and elicited a stimulatory effect on cell migration and invasion. Mechanistically, E2 induced ezrin activation was mediated by distinct mechanisms in different cell contexts. In SK-BR-3 cells with a high GPR30/ERβ ratio, silencing of GPR30 was able to abolish E2 induced ERK1/2, AKT phosphorylation and ezrin activation, whereas in MDA-MB-231 cells with low GPR30/ERβ ratio, E2 stimulated ezrin activation was mediated by the ERβ/PI3K/AKT signaling pathway. Importantly, we showed that activation of GPR30 signaling significantly prevents ERβ activation induced ezrin phosphorylation, cell migration and invasion, indicating an antagonist effect between GPR30 and ERβ signaling in MDA-MB-231 cells. These findings highlight the important interplay between different estrogen receptors in estrogen induced cell motility and invasiveness in ER-negative breast cancer cells.

STAT5A is regulated by DNA damage via the tumor suppressor p53

Here we report that the STAT5A transcription factor is a direct p53 transcriptional target gene. STAT5A is well expressed in p53 wild type cells but not in p53-null cells. Inhibition of p53 reduces STAT5A expression. DNA damaging agents such as doxorubicin also induced STAT5A expression in a p53 dependent manner. Two p53 binding sites were mapped in the STAT5A gene and named PBS1 and PBS2; these sites were sufficient to confer p53 responsiveness in a luciferase reporter gene. Chromatin immunoprecipitation experiments revealed that PBS2 has constitutive p53 bound to it, while p53 binding to PBS1 required DNA damage. In normal human breast lobules, weak p53 staining correlated with regions of intense STAT5A staining. Interestingly, in a cohort of triple negative breast tumor tissues there was little correlation between regions of p53 and STAT5A staining, likely reflecting a high frequency of p53 mutations that stabilize the protein in these tumors. We thus reveal an unexpected connection between cytokine signaling and p53.

Adherens junctions associated protein 1 serves as a predictor of recurrence of squamous cell carcinoma of the esophagus

Esophageal squamous cell carcinoma (ESCC), the most common esophageal cancer in East Asia, is among the six cancers with the highest fatality rates worldwide. Unfortunately, multidisciplinary treatment strategies have not achieved satisfactory outcomes. Therefore, novel insights into the molecular biology of ESCC are required to improve treatment. The gene encoding the transmembrane adherens junctions-associated protein-1 (AJAP1) expressed by epithelial cells resides in chromosome 1p36, which is frequently lost or epigenetically silenced in several malignancies. Here, we investigated the expression levels and regulatory mechanism of AJAP1 transcription. We determined the levels of AJAP1 mRNA and the genes encoding potentially interacting proteins expressed by ESCC cell lines, as well as the chromosomal copy number of AJAP1 and the methylation status of its promoter region. AJAP1 mRNA levels of 78 pairs of surgically resected specimens were determined to evaluate the association of AJAP1 expression and clinicopathological factors. Nine ESCC cell lines differentially expressed AJAP1 mRNA, and demethylation of hypermethylated AJAP1 genomic DNA reactivated AJAP1 mRNA expression. The copy number of sequences upstream or downstream of the AJAP1 transcriptional start site was not detectably altered. AJAP1 mRNA levels correlated inversely with those of ezrin (EZR) and were significantly lower in ESCC tissues compared with adjacent normal tissues. AJAP1 mRNA levels decreased gradually with increasing tumor stage. Patients with downregulated AJAP1 transcription were more likely to experience shorter overall and disease-free survival. Multivariate analysis of disease-free survival identified downregulated AJAP1 transcription as an independent prognostic factor. These results suggest that in ESCC, AJAP1 acts as a putative tumor suppressor and that AJAP1 transcription is regulated by promoter hypermethylation. These findings indicate that downregulated AJAP1 transcription may serve as a novel tumor biomarker to predict recurrence of ESCC after esophagectomy.

Translational implication of Kallmann syndrome-1 gene expression in hepatocellular carcinoma

Accumulation of epigenetic alterations causes inactivation of tumor suppressors and contributes to the initiation and progression of hepatocellular carcinoma (HCC). Identification of methylated genes is necessary to improve our understanding of the pathogenesis of HCC and develop novel biomarkers and therapeutic targets. The Kallmann syndrome-1 (KAL1) gene encodes an extracellular matrix-related protein with diverse oncological functions. However, the function of KAL1 in HCC has not been examined. We investigated the methylation status of the KAL1 promoter region in HCC cell lines, and evaluated KAL1 mRNA levels and those of genes encoding potential interacting cell adhesion factors. KAL1 mRNA expression level was heterogeneous in nine HCC cell lines, and reactivation of KAL1 mRNA expression was observed in cells with promoter hypermethylation of KAL1 gene after demethylation. In addition, KAL1 mRNA levels inversely correlated with those of ezrin in all nine HCC cell lines. KAL1 expression levels in 144 pairs of surgically-resected tissues were determined and correlated to clinicopathological parameters. KAL1 mRNA level was independent of the background liver status, whereas HCC tissues showed significantly lower KAL1 mRNA levels than corresponding noncancerous liver tissues. Downregulation of KAL1 mRNA in HCC was significantly associated with malignant phenotype characteristics, including elevated tumor markers, larger tumor size, vascular invasion, and hypermethylation of KAL1. Patients with downregulation of KAL1 were more likely to have a shorter overall survival than other patients, and multivariate analysis identified downregulation of KAL1 as an independent prognostic factor (hazard ratio 2.04, 95% confidence interval 1.11-3.90, P=0.022). Our results indicated that KAL1 may act as a putative tumor suppressor in HCC and is inactivated by promoter hypermethylation. KAL1 may serve as a biomarker of malignant phenotype of HCC.