ETV5 cooperates with LPP as a sensor of extracellular signals and promotes EMT in endometrial carcinomas

ETV5 facilitates tumor progression in head-neck squamous cell carcinoma

OBJECTIVE

E26 transformation-specific (ETS) factors have emerged as key mediators underlying human tumorigenesis. Here, we sought to characterize the expression pattern, biological roles, and clinical significance of ETS Variant Transcription Factor 5 (ETV5) in head neck squamous cell carcinoma (HNSCC).

SUBJECTS AND METHODS

ETV5 expression pattern in HNSCC was determined by bioinformatics interrogations and immunohistochemical staining in primary samples. The associations between its abundance with clinicopathological parameters, and patient survival were evaluated. Colony formation, CCK-8, flow cytometry, wound healing, and Transwell invasion assays, as well as xenograft models, were utilized to determine the phenotypic changes after ETV5 silencing in vitro and vivo. The potential binding of ETV5 in the Slug promoter was determined by ChIP-qPCR.

RESULTS

ETV5 was significantly overexpressed in HNSCC samples. Its overexpression is significantly associated with aggressiveness features and reduced survival. ETV5 knockdown significantly inhibited cell proliferation, migration, invasion, and induced apoptosis in vitro, and impaired tumor growth in vivo. Moreover, ETV5-activated Slug transcription by binding its promoter region in HNSCC cells. Patients with ETV5highSlughigh had the worst survival across multiple HNSCC cohorts.

CONCLUSIONS

Our findings reveal that ETV5 serves as a novel prognostic biomarker and putative oncogene for HNSCC progression likely by activating Slug transcription.

ETV5 Silencing Produces Mesenchymal to Epithelial Transition in INS-1 (832/13) Cell Line

ETV5 has been described to be involved in the epithelial to mesenchymal transition (EMT) mainly in cancer. It is known that EMT provokes cytoskeleton remodeling, improving cellular migratory, and invasive capabilities. Moreover, overexpression of ETV5 has been correlated to cancer development and this gene has been implicated in cell proliferation. However, little is known about the downregulation of ETV5 expression in a pancreatic cell line and the inverse mesenchymal to epithelial transition (MET). Therefore, we studied the implications of ETV5 silencing over the phenotype of the insulinoma INS-1 (832/13) cell line and described the MET by partial ETV5 silencing in the INS-1 (832/13) cell line. The downregulation of ETV5 expression was obtained by using ETV5 siRNA in the insulinoma rat cell line, INS-1 (832/13). Then, ETV5 knockdown provoked a MET phenotype observed by crystal violet staining and verified by immunohistochemistry against E-cadherin. Wound healing assay showed no migration, and F-actin stain revealed rearrangement of actin microfilaments. In addition, TGFβ1 and TGFβ3 were downregulated in the absence of ETV5. ETV5 silencing induces epithelial phenotype by downregulating TGFβ1 and TGFβ3 in INS-1 (832/13) cell line.

UBE2S interacting with TRIM21 mediates the K11-linked ubiquitination of LPP to promote the lymphatic metastasis of bladder cancer

Lymphatic metastasis is the most common pattern of bladder cancer (BCa) metastasis and has an extremely poor prognosis. Emerging evidence shows that ubiquitination plays crucial roles in various processes of tumors, including tumorigenesis and progression. However, the molecular mechanisms underlying the roles of ubiquitination in the lymphatic metastasis of BCa are largely unknown. In the present study, through bioinformatics analysis and validation in tissue samples, we found that the ubiquitin-conjugating E2 enzyme UBE2S was positively correlated with the lymphatic metastasis status, high tumor stage, histological grade, and poor prognosis of BCa patients. Functional assays showed that UBE2S promoted BCa cell migration and invasion in vitro, as well as lymphatic metastasis in vivo. Mechanistically, UBE2S interacted with tripartite motif containing 21 (TRIM21) and jointly induced the ubiquitination of lipoma preferred partner (LPP) via K11-linked polyubiquitination but not K48- or K63-linked polyubiquitination. Moreover, LPP silencing rescued the anti-metastatic phenotypes and inhibited the epithelial-mesenchymal transition of BCa cells after UBE2S knockdown. Finally, targeting UBE2S with cephalomannine distinctly inhibited the progression of BCa in cell lines and human BCa-derived organoids in vitro, as well as in a lymphatic metastasis model in vivo, without significant toxicity. In conclusion, our study reveals that UBE2S, by interacting with TRIM21, degrades LPP through K11-linked ubiquitination to promote the lymphatic metastasis of BCa, suggesting that UBE2S represents a potent and promising therapeutic target for metastatic BCa.

E26 transformation-specific transcription variant 5 in development and cancer: modification, regulation and function

E26 transformation-specific (ETS) transcription variant 5 (ETV5), also known as ETS-related molecule (ERM), exerts versatile functions in normal physiological processes, including branching morphogenesis, neural system development, fertility, embryonic development, immune regulation, and cell metabolism. In addition, ETV5 is repeatedly found to be overexpressed in multiple malignant tumors, where it is involved in cancer progression as an oncogenic transcription factor. Its roles in cancer metastasis, proliferation, oxidative stress response and drug resistance indicate that it is a potential prognostic biomarker, as well as a therapeutic target for cancer treatment. Post-translational modifications, gene fusion events, sophisticated cellular signaling crosstalk and non-coding RNAs contribute to the dysregulation and abnormal activities of ETV5. However, few studies to date systematically summarized the role and molecular mechanisms of ETV5 in benign diseases and in oncogenic progression. In this review, we specify the molecular structure and post-translational modifications of ETV5. In addition, its critical roles in benign and malignant diseases are summarized to draw a panorama for specialists and clinicians. The updated molecular mechanisms of ETV5 in cancer biology and tumor progression are delineated. Finally, we prospect the further direction of ETV5 research in oncology and its potential translational applications in the clinic.

An Individualized EMT-Related Gene Signature to Predict Recurrence-Free Survival in Stage II/III Colorectal Cancer Patients

BACKGROUND

Approximately 30% of stage II and 50-60% of stage III colorectal cancer (CRC) patients who have undergone surgery will develop recurrence within 5 years. Thus, more reliable prognostic biomarkers are urgently needed to identify the high-risk subset of patients who will benefit from postoperative adjuvant therapy.

METHODS

We retrospectively analyzed 911 stage II/III CRC patients in multiple cohorts. Using a series of bioinformatic and statistical approaches, an individualized prognostic signature was established in the training cohort and validated in four other independent cohorts. An integrated decision tree was generated to improve risk stratification, and a nomogram was built to quantify risk assessment for individual patients.

RESULTS

Epithelial-mesenchymal transition (EMT) was identified as a dominant risk factor for recurrence-free survival (RFS) in stage II/III CRC patients. The EMT-related gene signature could discriminate high-risk subsets in a training cohort and four independent validation cohorts (with 473, 89, 130, 74 and 145 patients, respectively). Survival analyses demonstrated that the EMT-related gene signature served as an independent risk factor for RFS in different subgroups. The decision tree could optimize the risk stratification, and the nomogram could predict the 5-year RFS probability accurately.

CONCLUSION

The proposed EMT-related prognostic signature is a useful biomarker to predict RFS and identify the high-risk subset in stage II/III CRC patients.

DEAD-Box Helicase 27 Triggers Epithelial to Mesenchymal Transition by Regulating Alternative Splicing of Lipoma-Preferred Partner in Gastric Cancer Metastasis

DEAD-box helicase 27 (DDX27) was previously identified as an important mediator during carcinogenesis, while its role in gastric cancer (GC) is not yet fully elucidated. Here, we aimed to investigate the mechanism and clinical significance of DDX27 in GC. Public datasets were analyzed to determine DDX27 expression profiling. The qRT-PCR, Western blot, and immunohistochemistry analyses were employed to investigate the DDX27 expression in GC cell lines and clinical samples. The role of DDX27 in GC metastasis was explored in vitro and in vivo. Mass spectrometry, RNA-seq, and alternative splicing analysis were conducted to demonstrate the DDX27-mediated molecular mechanisms in GC. We discovered that DDX27 was highly expressed in GCs, and a high level of DDX27 indicated poor prognosis. An increased DDX27 expression could promote GC metastasis, while DDX27 knockdown impaired GC aggressiveness. Mechanically, the LLP expression was significantly altered after DDX27 downregulation, and further results indicated that LPP may be regulated by DDX27 via alternative splicing. In summary, our study indicated that DDX27 contributed to GC malignant progression via a prometastatic DDX27/LPP/EMT regulatory axis.

Lin11-Isl1-Mec3 Domain Proteins as Mechanotransducers in Endothelial and Vascular Smooth Muscle Cells

Arterial hypertension is the leading risk factor for cardiovascular morbidity and mortality worldwide. However, little is known about the cellular mechanisms underlying it. In small arteries and arterioles, a chronic increase in blood pressure raises wall tension and hence stretches, namely, the medial vascular smooth muscle cells (VSMC) but also endothelial cell (EC) to cell contacts. Initially compensated by an increase in vascular tone, the continuous biomechanical strain causes a prominent change in gene expression in both cell types, frequently driving an arterial inward remodeling process that ultimately results in a reduction in lumen diameter, stiffening of the vessel wall, and fixation of blood pressure, namely, diastolic blood pressure, at the elevated level. Sensing and propagation of this supraphysiological stretch into the nucleus of VSMC and EC therefore seems to be a crucial step in the initiation and advancement of hypertension-induced arterial remodeling. Focal adhesions (FA) represent an important interface between the extracellular matrix and Lin11-Isl1-Mec3 (LIM) domain-containing proteins, which can translocate from the FA into the nucleus where they affect gene expression. The varying biomechanical cues to which vascular cells are exposed can thus be rapidly and specifically propagated to the nucleus. Zyxin was the first protein described with such mechanotransducing properties. It comprises 3 C-terminal LIM domains, a leucine-rich nuclear export signal, and N-terminal features that support its association with the actin cytoskeleton. In the cytoplasm, zyxin promotes actin assembly and organization as well as cell motility. In EC, zyxin acts as a transcription factor, whereas in VSMC, it has a less direct effect on mechanosensitive gene expression. In terms of homology and structural features, lipoma preferred partner is the nearest relative of zyxin among the LIM domain proteins. It is almost exclusively expressed by smooth muscle cells in the adult, resides like zyxin at FA but seems to affect mechanosensitive gene expression indirectly, possibly via altering cortical actin dynamics. Here, we highlight what is currently known about the role of these LIM domain proteins in mechanosensing and transduction in vascular cells.

Pharmacological inhibition of 17β-hydroxysteroid dehydrogenase impairs human endometrial cancer growth in an orthotopic xenograft mouse model

Endometrial cancer (EC) is the most common gynaecological tumor in developed countries and its incidence is increasing. Approximately 80% of newly diagnosed EC cases are estrogen-dependent. Type 1 17β-hydroxysteroid dehydrogenase (17β-HSD-1) is the enzyme that catalyzes the final step in estrogen biosynthesis by reducing the weak estrogen estrone (E1) to the potent estrogen 17β-estradiol (E2), and previous studies showed that this enzyme is implicated in the intratumoral E2 generation in EC. In the present study we employed a recently developed orthotopic and estrogen-dependent xenograft mouse model of EC to show that pharmacological inhibition of the 17β-HSD-1 enzyme inhibits disease development. Tumors were induced in one uterine horn of athymic nude mice by intrauterine injection of the well-differentiated human endometrial adenocarcinoma Ishikawa cell line, modified to express human 17β-HSD-1 in levels comparable to EC, and the luciferase and green fluorescent protein reporter genes. Controlled estrogen exposure in ovariectomized mice was achieved using subcutaneous MedRod implants that released either the low active estrone (E1) precursor or vehicle. A subgroup of E1 supplemented mice received daily oral gavage of FP4643, a well-characterized 17β-HSD-1 inhibitor. Bioluminescence imaging (BLI) was used to measure tumor growth non-invasively. At sacrifice, mice receiving E1 and treated with the FP4643 inhibitor showed a significant reduction in tumor growth by approximately 65% compared to mice receiving E1. Tumors exhibited metastatic spread to the peritoneum, to the lymphovascular space (LVI), and to the thoracic cavity. Metastatic spread and LVI invasion were both significantly reduced in the inhibitor-treated group. Transcriptional profiling of tumors indicated that FP4643 treatment reduced the oncogenic potential at the mRNA level. In conclusion, we show that 17β-HSD-1 inhibition represents a promising novel endocrine treatment for EC.

The role of E26 transformation-specific variant transcription factor 5 in colorectal cancer cell proliferation and cell cycle progression

E26 transformation-specific variant transcription factor 5 (ETV5) contributes to tumor growth and progression and promotes colorectal cancer (CRC) angiogenesis. Previous studies indicate that ETV5 may regulate the cell cycle, but its detailed mechanism remain unclear. Gene Ontology (GO) analysis of RNA-seq data revealed that ETV5 possibly regulates the cell cycle in CRC. Here, in vitro and in vivo experiments were performed to verify that ETV5 promoted tumor progression and influenced cell cycle G1/S transition. Cell cycle PCR array and co-immunoprecipitation (Co-IP) helped identify the p21-CDKs pathway. Chromatin immunoprecipitation (ChIP) and luciferase reporter assays were performed to determine whether ETV5 binds to the p21 promoter. ETV5 and p21 were detected by immunohistochemistry, and the effects of their expression on CRC patients were evaluated. ETV5 upregulation enhanced tumor proliferative capacity and promoted G1 phase transfer to the S phase. ETV5 knockdown slowed the growth of CRC cells and repressed the G1/S transition. We also found p21 as a downstream target of ETV5. p21 knockdown resulted in faster CRC cell growth and in more cells being driven from the G0/1 phase into the S phase. Co-IP experiments showed that p21 banding to CDK2, CDK4, and CDK6 inhibited p130 phosphorylation. Using the ChIP and luciferase reporter assay, we confirmed that ETV5 bound to the p21 promoter and repressed p21 expression. CRC patients with high ETV5 expression and low p21 expression showed the worst prognosis. Finally, by targeting p21 to regulate CDK function, ETV5 also changed drug-sensitivity to palbociclib and dinaciclib. In conclusion, ETV5 promoted cell cycle G1/S transition through transcriptional inhibition of p21, thereby accelerating tumor growth. Moreover, ETV5 changed drug-sensitivity to palbociclib and dinaciclib. Therefore, therapeutic regimens targeting ETV5 may be promising in improving the efficacy of target-CDK treatment in CRC.

Forkhead box D1 promotes EMT and chemoresistance by upregulating lncRNA CYTOR in oral squamous cell carcinoma

Chemotherapy regimens containing cisplatin remain the first-line treatments for patients with oral squamous cell cancer (OSCC); however, the treatment effect is often transient because of chemoresistance and recurrence. Understanding the mechanisms of chemoresistance in OSCC might provide novel targetable vulnerabilities. In the present study, we revealed that Forkhead box D1 (FOXD1) is upregulated in OSCC and predicted poor prognosis. Moreover, ectopic expression of FOXD1 promoted, while silencing of FOXD1 inhibited, the epithelial-mesenchymal transition (EMT) and chemoresistance of OSCC, both in vitro and in vivo. Mechanistically, FOXD1 binds to the promoter of long non-coding RNA Cytoskeleton Regulator RNA (CYTOR) and activates its transcription. CYTOR then acts as a competing endogenous RNA to inhibit miR-1252-5p and miR-3148, thus upregulating lipoma preferred partner (LPP) expression. Importantly, the CYTOR/LPP axis was proven to be essential for FOXD1-induced EMT and chemoresistance in OSCC. These findings reveal a novel mechanism for the chemotherapy resistance of OSCC, suggesting that FOXD1 might be a potential prognostic marker and anti-resistance therapeutic target.

Expression of lipoma preferred partner in mammary and extramammary Paget disease

BACKGOUND

This study aims to identify the expression of lipoma preferred partner (LPP) in Paget disease (PD) and to further understand the pathogenesis of PD.

METHODS

Tissue microarray was used to evaluate the expression of LPP by immunohistochemistry in 40 PD patients. The results of LPP expression were combined with clinical and histopathological characteristics. Patient files were analyzed retrospectively.

RESULTS

Twenty-one cases were mammary Paget disease (MPD) and 19 extramammary Paget disease (EMPD) involving the vulva, scrotum, and penis. LPP was expressed in PD and this expression was significantly greater in MPD versus EMPD (P = .031). The expression of LPP in MPD was significantly related with age (P = .009) and expression of Ki-67 (P = .011). No statistically significant differences were observed in LPP expression as related to sex, body location, and time of PD diagnosis.

CONCLUSIONS

While LPP is expressed in both MPD and EMPD, the intensity of this expression is greater in MPD. LPP expression is positively correlated with Ki-67 and is more prevalent in middle-aged versus senior MPD patients. Further research is needed to determine its potential role in tumorigenesis and distribution.

Identification of early stage recurrence endometrial cancer biomarkers using bioinformatics tools

Endometrial cancer (EC) is the sixth most common cancer in women worldwide. Early diagnosis is critical in recurrent EC management. The present study aimed to identify biomarkers of EC early recurrence using a workflow that combined text and data mining databases (DisGeNET, Gene Expression Omnibus), a prioritization algorithm to select a set of putative candidates (ToppGene), protein-protein interaction network analyses (Search Tool for the Retrieval of Interacting Genes, cytoHubba), association analysis of selected genes with clinicopathological parameters, and survival analysis (Kaplan-Meier and Cox proportional hazard ratio analyses) using a The Cancer Genome Atlas cohort. A total of 10 genes were identified, among which the targeting protein for Xklp2 (TPX2) was the most promising independent prognostic biomarker in stage I EC. TPX2 expression (mRNA and protein) was higher (P<0.0001 and P<0.001, respectively) in ETS variant transcription factor 5-overexpressing Hec1a and Ishikawa cells, a previously reported cell model of aggressive stage I EC. In EC biopsies, TPX2 mRNA expression levels were higher (P<0.05) in high grade tumors (grade 3) compared with grade 1–2 tumors (P<0.05), in tumors with deep myometrial invasion (>50% compared with <50%; P<0.01), and in intermediate-high recurrence risk tumors compared with low-risk tumors (P<0.05). Further validation studies in larger and independent EC cohorts will contribute to confirm the prognostic value of TPX2.

FXYD5/Dysadherin, a Biomarker of Endometrial Cancer Myometrial Invasion and Aggressiveness: Its Relationship With TGF-β1 and NF-κB Pathways

Objective: Endometrial cancer (EC) is the second most common gynecological cancer worldwide. Myometrial invasion (MI) is a key event in EC dissemination. This study aimed to evaluate FXYD5/dysadherin (FXYD5/Dys) expression in EC tissue and uterine aspirate (UA) biopsies and to assess molecular/functional changes associated with its expression in cellular models. Methods: FXYD5/Dys messenger RNA (mRNA) levels were determined in EC tissue and UA biopsies. FXYD5/Dys expression was evaluated in EC RNAseq data from The Cancer Genome Atlas (TCGA) and GENEVESTIGATOR tools. FXYD5/Dys impact on E-cadherin expression and cell behavior was assessed in EC Hec1a cells treated with transforming growth factor (TGF)-β1, stably transfected with ETV5, and transiently transfected with FXYD5/Dys small interfering RNA (siRNA) or pcDNA3-FXYD5/Dys plasmid. Results: FXYD5/Dys was associated with EC aggressiveness, finding high mRNA levels in tumors depicting MI > 50%, Grade 3, and intermediate/high risk of recurrence. FXYD5/Dys was highly expressed at the tumor invasive front compared to the superficial area. Most results were recapitulated in UA biopsies. FXYD5/Dys modulation in Hec1a cells altered cell migration/adhesion and E-cadherin expression. TGF-β1 treatment of Hec1a cells induced FXYD5/Dys expression. TCGA-UCEC RNAseq analysis revealed a positive correlation between FXYD5/Dys, TGF-β1, and plasminogen activator inhibitor (PAI)-1 mRNA levels. FXYD5/Dys induced nuclear factor (NF)-κB pathway activation in Hec1a cells. FXYD5/Dys mRNA levels positively correlated with transcriptional activation of NF-κB p65-regulated genes. Survival analysis revealed patient segregation into low- and high-risk groups, the latter depicting the highest FXYD5/Dys, PAI-1, tumor necrosis factor (TNF)-α, and TGF-β1 mRNA levels and shorter survival rates. Conclusion: FXYD5/Dys is a novel biomarker of EC progression related to TGF-β1 and NF-κB pathways that collectively promote tumor dissemination and result in poor patient prognosis.

Heterogeneity in Circulating Tumor Cells: The Relevance of the Stem-Cell Subset

The release of circulating tumor cells (CTCs) into vasculature is an early event in the metastatic process. The analysis of CTCs in patients has recently received widespread attention because of its clinical implications, particularly for precision medicine. Accumulated evidence documents a large heterogeneity in CTCs across patients. Currently, the most accepted view is that tumor cells with an intermediate phenotype between epithelial and mesenchymal have the highest plasticity. Indeed, the existence of a meta-stable or partial epithelial–mesenchymal transition (EMT) cell state, with both epithelial and mesenchymal features, can be easily reconciled with the concept of a highly plastic stem-like state. A close connection between EMT and cancer stem cells (CSC) traits, with enhanced metastatic competence and drug resistance, has also been described. Accordingly, a subset of CTCs consisting of CSC, present a stemness profile, are able to survive chemotherapy, and generate metastases after xenotransplantation in immunodeficient mice. In the present review, we discuss the current evidence connecting CTCs, EMT, and stemness. An improved understanding of the CTC/EMT/CSC connections may uncover novel therapeutic targets, irrespective of the tumor type, since most cancers seem to harbor a pool of CSCs, and disclose important mechanisms underlying tumorigenicity.

ETS variant 5 promotes colorectal cancer angiogenesis by targeting platelet-derived growth factor BB

ETS transcription factors play important roles in tumor cell invasion, differentiation and angiogenesis. In this study, we initially demonstrated that ETS translocation variant 5 (ETV5) is abnormally upregulated in colorectal cancer (CRC), is positively correlated with CRC tumor size, lymphatic metastasis and tumor node metastasis (TNM) stage and indicates shorter survival and disease-free survival in CRC patients. In vitro and in vivo experiments revealed that the downregulation of ETV5 could significantly suppress CRC cell proliferation. Moreover, overexpression of ETV5 could stimulate CRC angiogenesis in vitro and in vivo, which is consistent with RNA-seq results. Then, we identified platelet-derived growth factor BB (PDGF-BB) as a direct target of ETV5 that plays an important role in ETV5-mediated CRC angiogenesis through an angiogenesis antibody microarray. Additionally, PDGF-BB could activate VEGFA expression via the PDGFR-β/Src/STAT3 pathway in CRC cells and appeared to be positively correlated with ETV5 in CRC tissues. Finally, we revealed that ETV5 could bind directly to the promoter region of PDGF-BB and regulate its expression through ChIP and luciferase assays. Overall, our study suggested that the transcription factor ETV5 could stimulate CRC malignancy and promote CRC angiogenesis by directly targeting PDGF-BB. These findings suggest that EVT5 may be a potential new diagnostic and prognostic marker in CRC and that targeting ETV5 might be a potential therapeutic option for inhibiting CRC angiogenesis.

Proteomic Characterization of Epithelial-Like Extracellular Vesicles in Advanced Endometrial Cancer

Endometrial cancer (EC) is the most frequent gynecological cancer. Tumor dissemination affecting ∼20% of EC patients is characterized at the primary carcinoma by epithelial-to-mesenchymal transition (EMT) associated with myometrial infiltration. At distant sites, the interaction of circulating tumor cells (CTCs) with the microenvironment is crucial for metastatic colonization, with a participation of the extracellular vesicles (EVs). We comprehensively approached these primary and secondary sites to study the impact of tumor EVs on the metastatic efficiency of CTCs in EC. Tumor EVs in circulation reproduce the epithelial phenotype predominant in the primary carcinoma, whereas CTCs are characterized by an EMT phenotype. We modeled this EMT-related clinical scenario in the Hec1A endometrial cell line and characterized the epithelial-like EVs in circulation by SILAC proteome analysis. The identification of proteins involved in cell-cell and cell-matrix interaction and binding, together with in vitro evidence of an improved adhesion of CTC to a functionalized endothelium, suggests a contribution of the epithelial-like EVs in the homing of CTCs at metastatic sites. Accordingly, adhesion protein LGALS3BP was found to be significantly enriched in circulating EVs from a cohort of EC patients with a high risk of recurrence by targeted proteomics (multiple reaction monitoring), highlighting its potential in liquid biopsy in EC.

Identification of Novel Genes in Osteoarthritic Fibroblast-Like Synoviocytes Using Next-Generation Sequencing and Bioinformatics Approaches

Synovitis in osteoarthritis (OA) the consequence of low grade inflammatory process caused by cartilage breakdown products that stimulated the production of pro-inflammatory mediators by fibroblast-like synoviocytes (FLS). FLS participate in joint homeostasis and low grade inflammation in the joint microenvironment triggers FLS transformation. In the current study, we aimed to identify differentially expressed genes and potential miRNA regulations in human OA FLS through deep sequencing and bioinformatics approaches. The 245 differentially expressed genes in OA FLS were identified, and pathway analysis using various bioinformatics databases indicated their enrichment in functions related to altered extracellular matrix organization, cell adhesion and cellular movement. Moreover, among the 14 dysregulated genes with potential miRNA regulations identified, src kinase associated phosphoprotein 2 (SKAP2), adaptor related protein complex 1 sigma 2 subunit (AP1S2), PHD finger protein 21A (PHF21A), lipoma preferred partner (LPP), and transcription factor AP-2 alpha (TFAP2A) showed similar expression patterns in OA FLS and OA synovial tissue datasets in Gene Expression Omnibus database. Ingenuity Pathway Analysis identified the dysregulated LPP participated in cell migration and cell spreading of OA FLS, which was potentially regulated by miR-141-3p. The current findings suggested new perspectives into understanding the novel molecular signatures of FLS involved in the pathogenesis of OA, which may be potential therapeutic targets.

New susceptibility loci for cutaneous melanoma risk and progression revealed using a porcine model

Despite major advances, it is estimated that a large part of melanoma predisposing genes remains to be discovered. Animal models of spontaneous diseases are valuable tools and experimental crosses can be used to identify and fine-map new susceptibility loci associated with melanoma. We performed a Genome-Wide Association Study (GWAS) of melanoma occurrence and progression (clinical ulceration and presence of metastasis) in a porcine model of spontaneous melanoma, the MeLiM pig. Five loci on chromosomes 2, 5, 7, 8 and 16 showed genome-wide significant associations (p < 5 × 10^–6) with either one of these phenotypes. Suggestive associations (p < 5 × 10^–5) were also found at 16 additional loci. Moreover, comparison of the porcine results to those reported by human melanoma GWAS indicated shared association signals notably at CDKAL1 and TERT loci but also nearby CCND1, FTO, PLA2G6 and TMEM38B-RAD23B loci. Extensive search of the literature revealed a potential key role of genes at the identified porcine loci in tumor invasion (DST, PLEKHA5, CBY1, LIMK2 and ETV5) and immune response modulation (ETV5, HERC3 and DICER1) of the progression phenotypes. These biological processes are consistent with the clinico-pathological features of MeLiM tumors and can open new routes for future melanoma research in humans.

ALCAM shedding at the invasive front of the tumor is a marker of myometrial infiltration and promotes invasion in endometrioid endometrial cancer

Endometrial cancer (EC) is the sixth deadliest cancer in women. The depth of myometrial invasion is one of the most important prognostic factors, being directly associated with tumor recurrence and mortality. In this study, ALCAM, a previously described marker of EC recurrence, was studied by immunohistochemistry at the superficial and the invasive tumor areas from 116 EC patients with different degree of myometrial invasion and related to a set of relevant epithelial and mesenchymal markers. ALCAM expression presented a heterogeneous functionality depending on its localization, it correlated with epithelial markers (E-cadherin/β-catenin) at the superficial area, and with mesenchymal markers at the invasive front (COX-2, SNAIL, ETV5, and MMP-9). At the invasive front, ALCAM-negativity was an independent marker of myometrial invasion. This negativity, together with an increase of soluble ALCAM in uterine aspirates from patients with an invasive EC, and its positive correlation with MMP-9 levels, suggested that ALCAM shedding by MMP-9 occurs at the invasive front. In vivo and in vitro models of invasive EC were generated by ETV5-overexpression. In those, we demonstrated that ALCAM shedding was related to a more invasive pattern and that full-ALCAM recovery reverted most of the ETV5-cells mesenchymal abilities, partially through a p-ERK dependent-manner.

Emerging roles for LPP in metastatic cancer progression

LIM domain containing proteins are important regulators of diverse cellular processes, and play pivotal roles in regulating the actin cytoskeleton. Lipoma Preferred Partner (LPP) is a member of the zyxin family of LIM proteins that has long been characterized as a promoter of mesenchymal/fibroblast cell migration. More recently, LPP has emerged as a critical inducer of tumor cell migration, invasion and metastasis. LPP is thought to contribute to these malignant phenotypes by virtue of its ability to shuttle into the nucleus, localize to adhesions and, most recently, to promote invadopodia formation. In this review, we will examine the mechanisms through which LPP regulates the functions of adhesions and invadopodia, and discuss potential roles of LPP in mediating cellular responses to mechanical cues within these mechanosensory structures.

Metabolomic and Lipidomic Profiling Identifies The Role of the RNA Editing Pathway in Endometrial Carcinogenesis

Endometrial cancer (EC) remains the most common malignancy of the genital tract among women in developed countries. Although much research has been performed at genomic, transcriptomic and proteomic level, there is still a significant gap in the metabolomic studies of EC. In order to gain insights into altered metabolic pathways in the onset and progression of EC carcinogenesis, we used high resolution mass spectrometry to characterize the metabolomic and lipidomic profile of 39 human EC and 17 healthy endometrial tissue samples. Several pathways including lipids, Kynurenine pathway, endocannabinoids signaling pathway and the RNA editing pathway were found to be dysregulated in EC. The dysregulation of the RNA editing pathway was further investigated in an independent set of 183 human EC tissues and matched controls, using orthogonal approaches. We found that ADAR2 is overexpressed in EC and that the increase in expression positively correlates with the aggressiveness of the tumor. Furthermore, silencing of ADAR2 in three EC cell lines resulted in a decreased proliferation rate, increased apoptosis, and reduced migration capabilities in vitro. Taken together, our results suggest that ADAR2 functions as an oncogene in endometrial carcinogenesis and could be a potential target for improving EC treatment strategies.

Epithelial-to-Mesenchymal Transition in the Female Reproductive Tract: From Normal Functioning to Disease Pathology

Epithelial-to-mesenchymal transition (EMT) is a physiological process that is vital throughout the human lifespan. In addition to contributing to the development of various tissues within the growing embryo, EMT is also responsible for wound healing and tissue regeneration later in adulthood. In this review, we highlight the importance of EMT in the development and normal functioning of the female reproductive organs (the ovaries and the uterus) and describe how dysregulation of EMT can lead to pathological conditions, such as endometriosis, adenomyosis, and carcinogenesis. We also summarize the current literature relating to EMT in the context of ovarian and endometrial carcinomas, with a particular focus on how molecular mechanisms and the tumor microenvironment can govern cancer cell plasticity, therapy resistance, and metastasis.

A human endogenous retrovirus-derived gene that can contribute to oncogenesis by activating the ERK pathway and inducing migration and invasion

Endogenous retroviruses are cellular genes of retroviral origin captured by their host during the course of evolution and represent around 8% of the human genome. Although most are defective and transcriptionally silenced, some are still able to generate retroviral-like particles and proteins. Among these, the HERV-K(HML2) family is remarkable since its members have amplified relatively recently and many of them still have full length coding genes. Furthermore, they are induced in cancers, especially in melanoma, breast cancer and germ cell tumours, where viral particles, as well as the envelope protein (Env), can be detected. Here we show that HERV-K(HML2) Env per se has oncogenic properties. Its expression in a non-tumourigenic human breast epithelial cell line induces epithelial to mesenchymal transition (EMT), often associated with tumour aggressiveness and metastasis. In our model, this is typified by key modifications in a set of molecular markers, changes in cell morphology and enhanced cell motility. Remarkably, microarrays performed in 293T cells reveal that HERV-K(HML2) Env is a strong inducer of several transcription factors, namely ETV4, ETV5 and EGR1, which are downstream effectors of the MAPK ERK1/2 and are associated with cellular transformation. We demonstrate that HERV-K(HML2) Env effectively activates the ERK1/2 pathway in our experimental setting and that this activation depends on the Env cytoplasmic tail. In addition, this phenomenon is very specific, being absent with every other retroviral Env tested, except for Jaagsiekte Sheep Retrovirus (JSRV) Env, which is already known to have transforming properties in vivo. Though HERV-K Env is not directly transforming by itself, the newly discovered properties of this protein may contribute to oncogenesis.

Nearly half the DNA of mammals consists of reitarated, selfish elements that can move and amplify within the genome. With time, some of these elements are recruited by the host and the proteins they encode are used to fulfill physiological functions, whereas other elements have conserved some of their pathological properties and contribute to the development of diseases. The human HERV-K(HML2) elements originated from an ancestral infection of the primate germline by an infectious retrovirus that has been maintained and amplified in the human lineage. It is associated with several pathologies in modern humans, in particular cancer of the breast, germline and skin. We show that the HERV-K(HML2) envelope protein is able to activate a major cellular signalling pathway often involved in human cancers, and that its expression promotes a series of cellular changes that are characteristic of cancer development. Altogether, this study indicates that the expression of HERV-K(HML2) elements is not only a marker of cancer, but can also directly participate to tumourigenesis via the newly discovered oncogenic properties carried by the envelope protein.

Dual effects of constitutively active androgen receptor and full-length androgen receptor for N-cadherin regulation in prostate cancer

Constitutively active androgen receptor (AR) variants have been involved in the expression of mesenchymal markers such as N-cadherin in prostate cancer (PCa). However, the underlying molecular mechanisms remain elusive. It remains unclear, whether N-cadherin gene (CDH2) is a direct transcriptional target of AR variants or whether the observed upregulation is due to indirect effects through additional regulatory factors. Moreover, the specific contribution of full-length AR and AR variants in N-cadherin regulation in PCa has never been explored deeply. To investigate this, we artificially mimicked the co-expression of AR variants together with a full-length AR and performed miRNA-seq, RNA-seq and ChIP assays. Our results were in favor of a direct AR variants action on CDH2. Our data also revealed a distinctive mode of action between full-length AR and AR variants to regulate N-cadherin expression. Both wild type AR and AR variants could interact with a regulatory element in intron 1 of CDH2. However, a higher histone H4 acetylation in this genomic region was only observed with AR variants. This suggests that full-length AR may play an occluding function to impede CDH2 upregulation. Our data further highlighted a negative effect of AR variants on the expression of the endogenous full-length AR in LNCaP. These differences in the mode of action of AR variants and full-length AR for the control of one key gene for prostate cancer progression could be worth considering for targeting AR variants in PCa.

Activated leukocyte cell adhesion molecule (ALCAM) is a marker of recurrence and promotes cell migration, invasion, and metastasis in early-stage endometrioid endometrial cancer

Endometrial cancer is the most common gynaecological cancer in western countries, being the most common subtype of endometrioid tumours. Most patients are diagnosed at an early stage and present an excellent prognosis. However, a number of those continue to suffer recurrence, without means of identification by risk classification systems. Thus, finding a reliable marker to predict recurrence becomes an important unmet clinical issue. ALCAM is a cell-cell adhesion molecule and member of the immunoglobulin superfamily that has been associated with the genesis of many cancers. Here, we first determined the value of ALCAM as a marker of recurrence in endometrioid endometrial cancer by conducting a retrospective multicentre study of 174 primary tumours. In early-stage patients (N = 134), recurrence-free survival was poorer in patients with ALCAM-positive compared to ALCAM-negative tumours (HR 4.237; 95% CI 1.01-17.76). This difference was more significant in patients with early-stage moderately-poorly differentiated tumours (HR 9.259; 95% CI 2.12-53.47). In multivariate analysis, ALCAM positivity was an independent prognostic factor in early-stage disease (HR 6.027; 95% CI 1.41-25.74). Then we demonstrated in vitro a role for ALCAM in cell migration and invasion by using a loss-of-function model in two endometrial cancer cell lines. ALCAM depletion resulted in a reduced primary tumour size and reduced metastatic local spread in an orthotopic murine model. Gene expression analysis of ALCAM-depleted cell lines pointed to motility, invasiveness, cellular assembly, and organization as the most deregulated functions. Finally, we assessed some of the downstream effector genes that are involved in ALCAM-mediated cell migration; specifically FLNB, TXNRD1, and LAMC2 were validated at the mRNA and protein level. In conclusion, our results highlight the potential of ALCAM as a recurrent biomarker in early-stage endometrioid endometrial cancer and point to ALCAM as an important molecule in endometrial cancer dissemination by regulating cell migration, invasion, and metastasis. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

EGFR-Based Immunoisolation as a Recovery Target for Low-EpCAM CTC Subpopulation

Circulating tumour cells (CTCs) play a key role in the metastasis process, as they are responsible for micrometastasis and are a valuable tool for monitoring patients in real-time. Moreover, efforts to develop new strategies for CTCs isolation and characterisation, and the translation of CTCs into clinical practice needs to overcome the limitation associated with the sole use of Epithelial Cell Adhesion Molecule (EpCAM) expression to purify this tumour cell subpopulation. CTCs are rare events in the blood of patients and are believed to represent the epithelial population from a primary tumour of epithelial origin, thus EpCAM immunoisolation is considered an appropriate strategy. The controversy stems from the impact that the more aggressive mesenchymal tumour phenotypes might have on the whole CTC population. In this work, we first characterised a panel of cell lines representative of tumour heterogeneity, confirming the existence of tumour cell subpopulations with restricted epithelial features and supporting the limitations of EpCAM-based technologies. We next developed customised polystyrene magnetic beads coated with antibodies to efficiently isolate the phenotypically different subpopulations of CTCs from the peripheral blood mononuclear cells (PBMCs) of patients with metastatic cancer. Besides EpCAM, we propose Epidermal Growth Factor Receptor (EGFR) as an additional isolation marker for efficient CTCs detection.

Tumor progression, metastasis, and modulators of epithelial-mesenchymal transition in endometrioid endometrial carcinoma: an update

Endometrioid endometrial carcinoma (EEC), also known as type 1 endometrial cancer (EC), accounts for over 70-80% of all cases that are usually associated with estrogen stimulation and often develops in a background of atypical endometrial hyperplasia. The increased incidence of EC is mainly confined to this type of cancer. Most EEC patients present at an early stage and generally have a favorable prognosis; however, up to 30% of EEC present as high risk tumors, which have invaded deep into the myometrium at diagnosis and progressively lead to local or extra pelvic metastasis. The poor survival of advanced EC is related to the lack of effective therapies, which can be attributed to poor understanding of the molecular mechanisms underlying the progression of disease toward invasion and metastasis. Multiple lines of evidence illustrate that epithelial-mesenchymal transition (EMT)-like events are central to tumor progression and malignant transformation, endowing the incipient cancer cell with invasive and metastatic properties. The aim of this review is to summarize the current knowledge on molecular events associated with EMT in progression, invasion, and metastasis of EEC. Further, the role of epigenetic modifications and microRNA regulation, tumor microenvironment, and microcystic elongated and fragmented glands like invasion pattern have been discussed. We believe this article may perhaps stimulate further research in this field that may aid in identifying high risk patients within this clinically challenging patient group and also lead to the recognition of novel targets for the prevention of metastasis - the most fatal consequence of endometrial carcinogenesis.

EMT-Inducing Molecular Factors in Gynecological Cancers

Gynecologic cancers are the unregulated growth of neoplastic cells that arise in the cervix, ovaries, fallopian tubes, uterus, vagina, and vulva. Although gynecologic cancers are characterized by different signs and symptoms, studies have shown that they share common risk factors, such as smoking, obesity, age, exposure to certain chemicals, infection with human immunodeficiency virus (HIV), and infection with human papilloma virus (HPV). Despite recent advancements in the preventative, diagnostic, and therapeutic interventions for gynecologic cancers, many patients still die as a result of metastasis and recurrence. Since mounting evidence indicates that the epithelial-mesenchymal transition (EMT) process plays an essential role in metastatic relapse of cancer, understanding the molecular aberrations responsible for the EMT and its underlying signaling should be given high priority in order to reduce cancer morbidity and mortality.

Nidogen 1 and Nuclear Protein 1: novel targets of ETV5 transcription factor involved in endometrial cancer invasion

Endometrial cancer is the most frequent malignancy of the female genital tract in western countries. Our group has previously characterized the upregulation of the transcription factor ETV5 in endometrial cancer with a specific and significant increase in those tumor stages associated with myometrial invasion. We have shown that ETV5 overexpression in Hec1A endometrial cancer cells induces epithelial to mesenchymal transition resulting in the acquisition of migratory and invasive capabilities. In the present work, we have identified Nidogen 1 (NID1) and Nuclear Protein 1 (NUPR1) as direct transcriptional targets of ETV5 in endometrial cancer cells. Inhibition of NID1 and NUPR1 in ETV5 overexpressing cells reduced cell migration and invasion in vitro and reduced tumor growth and dissemination in an orthotopic endometrial cancer model. Importantly, we confirmed a significant increase of NUPR1 and NID1 protein expression in the invasion front of the tumor compared to their paired superficial zone, concomitant to ETV5 overexpression. Altogether, we conclude that NID1 and NUPR1 are novel targets of ETV5 and are actively cooperating with ETV5 at the invasion front of the tumor in the acquisition of an invasive phenotype to jointly drive endometrial cancer invasion.

Molecular profiling of circulating tumor cells links plasticity to the metastatic process in endometrial cancer

BACKGROUND

About 20% of patients diagnosed with endometrial cancer (EC) are considered high-risk with unfavorable prognosis. In the framework of the European Network for Individualized Treatment in EC (ENITEC), we investigated the presence and phenotypic features of Circulating Tumor Cells (CTC) in high-risk EC patients.

METHODS

CTC isolation was carried out in peripheral blood samples from 34 patients, ranging from Grade 3 Stage IB to Stage IV carcinomas and recurrences, and 27 healthy controls using two methodologies. Samples were subjected to EpCAM-based immunoisolation using the CELLection™ Epithelial Enrich kit (Invitrogen, Dynal) followed by RTqPCR analysis. The phenotypic determinants of endometrial CTC in terms of pathogenesis, hormone receptor pathways, stem cell markers and epithelial to mesenchymal transition (EMT) drivers were asked. Kruskal-Wallis analysis followed by Dunn's post-test was used for comparisons between groups. Statistical significance was set at p < 0.05.

RESULTS

EpCAM-based immunoisolation positively detected CTC in high-risk endometrial cancer patients. CTC characterization indicated a remarkable plasticity phenotype defined by the expression of the EMT markers ETV5, NOTCH1, SNAI1, TGFB1, ZEB1 and ZEB2. In addition, the expression of ALDH and CD44 pointed to an association with stemness, while the expression of CTNNB1, STS, GDF15, RELA, RUNX1, BRAF and PIK3CA suggested potential therapeutic targets. We further recapitulated the EMT phenotype found in endometrial CTC through the up-regulation of ETV5 in an EC cell line, and validated in an animal model of systemic dissemination the propensity of these CTC in the accomplishment of metastasis.

CONCLUSIONS

Our results associate the presence of CTC with high-risk EC. Gene-expression profiling characterized a CTC-plasticity phenotype with stemness and EMT features. We finally recapitulated this CTC-phenotype by over-expressing ETV5 in the EC cell line Hec1A and demonstrated an advantage in the promotion of metastasis in an in vivo mouse model of CTC dissemination and homing.

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

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

Integrating gene expression and epidemiological data for the discovery of genetic interactions associated with cancer risk

Dozens of common genetic variants associated with cancer risk have been identified through genome-wide association studies (GWASs). However, these variants only explain a modest fraction of the heritability of disease. The missing heritability has been attributed to several factors, among them the existence of genetic interactions (G × G). Systematic screens for G × G in model organisms have revealed their fundamental influence in complex phenotypes. In this scenario, G × G overlap significantly with other types of gene and/or protein relationships. Here, by integrating predicted G × G from GWAS data and complex- and context-defined gene coexpression profiles, we provide evidence for G × G associated with cancer risk. G × G predicted from a breast cancer GWAS dataset identified significant overlaps [relative enrichments (REs) of 8-36%, empirical P values < 0.05 to 10(-4)] with complex (non-linear) gene coexpression in breast tumors. The use of gene or protein data not specific for breast cancer did not reveal overlaps. According to the predicted G × G, experimental assays demonstrated functional interplay between lipoma-preferred partner and transforming growth factor-β signaling in the MCF10A non-tumorigenic mammary epithelial cell model. Next, integration of pancreatic tumor gene expression profiles with pancreatic cancer G × G predicted from a GWAS corroborated the observations made for breast cancer risk (REs of 25-59%). The method presented here can potentially support the identification of genetic interactions associated with cancer risk, providing novel mechanistic hypotheses for carcinogenesis.

Loss of a negative feedback loop involving pea3 and cyclin d2 is required for pea3-induced migration in transformed mammary epithelial cells

The Ets family transcription factor Pea3 (ETV4) is involved in tumorigenesis especially during the metastatic process. Pea3 is known to induce migration and invasion in mammary epithelial cell model systems. However, the molecular pathways regulated by Pea3 are still misunderstood. In the current study, using in vivo and in vitro assays, Pea3 increased the morphogenetic and tumorigenic capacity of mammary epithelial cells by modulating their cell morphology, proliferation, and migration potential. In addition, Pea3 overexpression favored an epithelial-mesenchymal transition (EMT) triggered by TGF-β1. During investigation for molecular events downstream of Pea3, Cyclin D2 (CCND2) was identified as a new Pea3 target gene involved in the control of cellular proliferation and migration, a finding that highlights a new negative regulatory loop between Pea3 and Cyclin D2. Furthermore, Cyclin D2 expression was lost during TGF-β1-induced EMT and Pea3-induced tumorigenesis. Finally, restored Cyclin D2 expression in Pea3-dependent mammary tumorigenic cells decreased cell migration in an opposite manner to Pea3. As such, these data demonstrate that loss of the negative feedback loop between Cyclin D2 and Pea3 contributes to Pea3-induced tumorigenesis.

IMPLICATIONS

This study reveals molecular insight into how the Ets family transcription factor Pea3 favors EMT and contributes to tumorigenesis via a negative regulatory loop with Cyclin D2, a new Pea3 target gene.

A complex containing LPP and α-actinin mediates TGFβ-induced migration and invasion of ErbB2-expressing breast cancer cells

Transforming growth factor β (TGFβ) is a potent modifier of the malignant phenotype in ErbB2-expressing breast cancers. We demonstrate that epithelial-derived breast cancer cells, which undergo a TGFβ-induced epithelial-to-mesenchymal transition (EMT), engage signaling molecules that normally facilitate cellular migration and invasion of mesenchymal cells. We identify lipoma preferred partner (LPP) as an indispensable regulator of TGFβ-induced migration and invasion of ErbB2-expressing breast cancer cells. We show that LPP re-localizes to focal adhesion complexes upon TGFβ stimulation and is a critical determinant in TGFβ-mediated focal adhesion turnover. Finally, we have determined that the interaction between LPP and α-actinin, an actin cross-linking protein, is necessary for TGFβ-induced migration and invasion of ErbB2-expressing breast cancer cells. Thus, our data reveal that LPP, which is normally operative in cells of mesenchymal origin, can be co-opted by breast cancer cells during an EMT to promote their migration and invasion.

Erg is a crucial regulator of endocardial-mesenchymal transformation during cardiac valve morphogenesis

During murine embryogenesis, the Ets factor Erg is highly expressed in endothelial cells of the developing vasculature and in articular chondrocytes of developing bone. We identified seven isoforms for the mouse Erg gene. Four share a common translational start site encoded by exon 3 (Ex3) and are enriched in chondrocytes. The other three have a separate translational start site encoded by Ex4 and are enriched in endothelial cells. Homozygous Erg^ΔEx3/ΔEx3 knockout mice are viable, fertile and do not display any overt phenotype. By contrast, homozygous Erg^ΔEx4/ΔEx4 knockout mice are embryonic lethal, which is associated with a marked reduction in endocardial-mesenchymal transformation (EnMT) during cardiac valve morphogenesis. We show that Erg is required for the maintenance of the core EnMT regulatory factors that include Snail1 and Snail2 by binding to their promoter and intronic regions.

The EMT signaling pathways in endometrial carcinoma

Endometrial cancer (EC) is the most common gynecologic malignancy of the female genital tract and the fourth most common neoplasia in women. In EC, myometrial invasion is considered one of the most important prognostic factors. For this process to occur, epithelial tumor cells need to undergo an epithelial to mesenchymal transition (EMT), either transiently or stably, and to differing degrees. This process has been extensively described in other types of cancer but has been poorly studied in EC. In this review, several features of EMT and the main molecular pathways responsible for triggering this process are investigated in relation to EC. The most common hallmarks of EMT have been found in EC, either at the level of E-cadherin loss or at the induction of its repressors, as well as other molecular alterations consistent with the mesenchymal phenotype-like L1CAM and BMI-1 up-regulation. Pathways including progesterone receptor, TGFβ, ETV5 and microRNAs are deeply related to the EMT process in EC.

Lipoma preferred partner is a mechanosensitive protein regulated by nitric oxide in the heart

Adaptor proteins play an important role in signaling pathways by providing a platform on which many other proteins can interact. Malfunction or mislocalization of these proteins may play a role in the development of disease. Lipoma preferred partner (LPP) is a nucleocytoplasmic shuttling adaptor protein. Previous work shows that LPP plays a role in the function of smooth muscle cells and in atherosclerosis. In this study we wanted to determine whether LPP has a role in the myocardium. LPP expression increased by 56% in hearts from pressure overload aortic-banded rats (p < 0.05 n = 4), but not after myocardial infarction, suggesting hemodynamic load regulates its expression. In vitro, LPP expression was 87% higher in cardiac fibroblasts than myocytes (p < 0.05 n = 3). LPP expression was downregulated in the absence of the actin cytoskeleton but not when microtubules were disassembled. We mechanically stretched cardiac fibroblasts using the Flexcell 4000 for 48 h (1 Hz, 5% maximum strain), which decreased total LPP total expression and membrane localization in subcellular fractions (p < 0.05, n = 5). However, L-NAME, an inhibitor of nitric oxide synthase (NOS), significantly upregulated LPP expression. These findings suggest that LPP is regulated by a complex interplay between NO and mechanical cues and may play a role in heart failure induced by increased hemodynamic load.