Expression of the Ets transcription factor EHF in serous ovarian carcinoma effusions is a marker of poor survival

Transcription factor EHF drives cholangiocarcinoma development through transcriptional activation of glioma-associated oncogene homolog 1 and chemokine CCL2

Cholangiocarcinoma (CCA) is characterized by rapid onset and high chance of metastasis. Therefore, identification of novel therapeutic targets is imperative. E26 transformation-specific homologous factor (EHF), a member of the E26 transformation-specific transcription factor family, plays a pivotal role in epithelial cell differentiation and cancer progression. However, its precise role in CCA remains unclear. In this study, through in vitro and in vivo experiments, we demonstrated that EHF plays a profound role in promoting CCA by transcriptional activation of glioma-associated oncogene homolog 1 (GLI1). Moreover, EHF significantly recruited and activated tumor-associated macrophages (TAMs) through the C-C motif chemokine 2/C-C chemokine receptor type 2 (CCL2/CCR2) axis, thereby remodeling the tumor microenvironment. In human CCA tissues, EHF expression was positively correlated with GLI1 and CCL2 expression, and patients with co-expression of EHF/GLI1 or EHF/CCL2 had the most adverse prognosis. Furthermore, the combination of the GLI1 inhibitor, GANT58, and CCR2 inhibitor, INCB3344, substantially reduced the occurrence of EHF-mediated CCA. In summary, our findings suggest that EHF is a potential prognostic biomarker for patients with CCA, while also advocating the therapeutic approach of combined targeting of GLI1 and CCL2/CCR2-TAMs to inhibit EHF-driven CCA development.

Anticancer Effect of E26 Transformation-Specific Homologous Factor through the Induction of Senescence and the Inhibition of Epithelial-Mesenchymal Transition in Triple-Negative Breast Cancer Cells

The aim of the present study was to evaluate the effect of ETS homologous factor (EHF) in malignant breast cancer cells. The overexpression and knockdown of the EHF gene in human and mouse breast cancer cells were performed, and the TCGA dataset and Q-omics were analyzed. We found that the tumor suppressor NDRG2 is correlated with EHF gene expression in triple-negative breast cancer cells, that EHF overexpression results in reduced cell proliferation and that apoptosis is promoted by the chemotherapeutic reagent treatment of EHF-overexpressing cells. By EHF overexpression, senescence-associated β-galactosidase activity and p21WAF1/CIP1 expression were increased, suggesting that EHF may induce cellular senescence. In addition, the overexpression of EHF reduced the migratory ability and inhibited epithelial-mesenchymal transition (EMT). Furthermore, EHF inhibited the phosphorylation of STAT3. The overexpression of EHF also reduced the tumor size, and lung metastasis in vivo. At the tumor site, β-galactosidase activity was increased by EHF. Finally, the Kaplan-Meier-plotter analysis showed that TNBC patients with a high expression of EHF had a longer relapse-free survival rate. Our findings demonstrated that EHF inhibits breast tumor progression by inducing senescence and regulating EMT in TNBC cells.

Multi-Organ Nutrigenomic Effects of Dietary Grapes in a Mouse Model

As a whole food, the potential health benefits of table grapes have been widely studied. Some individual constituents have garnered great attention, particularly resveratrol, but normal quantities in the diet are meniscal. On the other hand, the grape contains hundreds of compounds, many of which have antioxidant potential. Nonetheless, the achievement of serum or tissue concentrations of grape antioxidants sufficient to mediate a direct quenching effect is not likely, which supports the idea of biological responses being mediated by an indirect catalytic-type response. We demonstrate herein with Hsd:ICR (CD-1® Outbred, 18-24 g, 3-4 weeks old, female) mice that supplementation of a semi-synthetic diet with a grape surrogate, equivalent to the human consumption of 2.5 servings per day for 12 months, modulates gene expression in the liver, kidney, colon, and ovary. As might be expected when sampling changes in a pool of over 35,000 genes, there are numerous functional implications. Analysis of some specific differentially expressed genes suggests the potential of grape consumption to bolster metabolic detoxification and regulation of reactive oxygen species in the liver, cellular metabolism, and anti-inflammatory activity in the ovary and kidney. In the colon, the data suggest anti-inflammatory activity, suppression of mitochondrial dysfunction, and maintaining homeostasis. Pathway analysis reveals a combination of up- and down-regulation in the target tissues, primarily up-regulated in the kidney and down-regulated in the ovary. More broadly, based on these data, it seems logical to conclude that grape consumption leads to modulation of gene expression throughout the body, the consequence of which may help to explain the broad array of activities demonstrated in diverse tissues such as the brain, heart, eye, bladder, and colon. In addition, this work further supports the profound impact of nutrigenomics on mammalian phenotypic expression.

Primary Ovarian Mesothelioma: A Case Series with Electron Microscopy Examination and Review of the Literature

Primary ovarian mesothelioma is a rare, aggressive neoplastic disease with a poor prognosis. At onset, the tumor is only rarely limited to the ovaries and usually already widespread in the peritoneum. The rarity of this entity and the difficulties differentiating it from either ovarian carcinoma or peritoneal mesothelioma may lead to frequent misdiagnoses and may raise some concerns about its histogenesis. Thus, reporting such rare cases is fundamental to gain greater awareness of this neoplasm and try to answer unsolved questions. Herein, we described four cases of histological diagnoses of ovarian mesothelioma extrapolated by the regional mesothelioma register of Apulia (southern Italy). In all cases, a detailed medical history was collected according to national mesothelioma register guidelines. A broad panel of antibodies was used for immunohistochemistry to confirm the diagnoses. Moreover, ovarian tissue samples were also examined by transmission and scanning electron microscopy, detecting asbestos fibers and talc crystals in two cases. Because of the few cases described, we reviewed the English literature in the Medline database, focusing on articles about ovarian mesothelioma "misclassification", "misdiagnosis", "diagnostic challenge" or "diagnostic pitfall" and on unsolved questions about its histogenesis and possible risk factors.

EHF enhances malignancy by modulating AKT and MAPK/ERK signaling in non‑small cell lung cancer cells

Overexpression of ETS‑homologous factor (EHF) in non‑small cell lung cancer (NSCLC) is associated with poor patient prognosis. To explore the mechanism of the effect of EHF in NSCLC, EHF expression was examined in NSCLC and its role in cell proliferation, invasion, cell cycle, and apoptosis of NSCLC cells was evaluated by overexpressing EHF and/or knocking down EHF expression in NSCLC cells in vitro and in cancer cell grafted mice in vivo. The results revealed that the knockdown of EHF expression in NSCLC with siRNA significantly inhibited cell proliferation and invasion, arrested the cell cycle at the G₀/G₁ phase, and induced apoptosis, whereas overexpression of EHF in NSCLC promoted cell proliferation, tumor growth, and cancer cell migration in vitro. The in vivo experiments demonstrated that siRNA‑mediated downregulation of EHF expression in NSCLC cells significantly suppressed tumor growth in xenografted nude mice as compared to cancer progression in the mice grafted with NSCLC cells transfected with non‑specific control siRNA. The biochemical analyses revealed that EHF promoted NSCLC growth by regulating the transcription of Erb‑B2 receptor tyrosine kinase 2/3 (ERBB2, ERBB3) and mesenchymal‑epithelial transition (MET) factor tyrosine kinase receptors and modulating the AKT and ERK signaling pathways in the NSCLC cells. The present findings indicated that EHF could be used as a prognostic marker for NSCLC, and tyrosine kinase receptors of ERBB2, ERBB3 and MET could be drug targets for NSCLC treatment.

Blockage of ETS homologous factor inhibits the proliferation and invasion of gastric cancer cells through the c-Met pathway

BACKGROUND

Gastric cancer (GC) is one of the most common and deadliest types of cancer worldwide due to its delayed diagnosis and high metastatic frequency, but its exact pathogenesis has not been fully elucidated. ETS homologous factor (EHF) is an important member of the ETS family and contributes to the pathogenesis of multiple malignant tumors. To date, whether EHF participates in the development of GC via the c-Met signaling pathway remains unclear.

AIM

To investigate the role and mechanism of EHF in the occurrence and development of GC.

METHODS

The expression of EHF mRNA in GC tissues and cell lines was measured by quantitative PCR. Western blotting was performed to determine the protein expression of EHF, c-Met, and its downstream signal molecules. The EHF expression in GC tissues was further detected by immunohistochemical staining. To investigate the role of EHF in GC oncogenesis, small interfering RNA (siRNA) against EHF was transfected into GC cells. The cell proliferation of GC cells was determined by Cell Counting Kit-8 and colony formation assays. Flow cytometry was performed following Annexin V/propidium iodide (PI) to identify apoptotic cells and PI staining to analyze the cell cycle. Cell migration and invasion were assessed by transwell assays.

RESULTS

The data showed that EHF was upregulated in GC tissues and cell lines in which increased expression of c-Met was also observed. Silencing of EHF by siRNA reduced the proliferation of GC cells. Inhibition of EHF induced significant apoptosis and cell cycle arrest in GC cells. Cell migration and invasion were significantly inhibited. EHF silencing led to c-Met downregulation and further blocked the Ras/c-Raf/extracellular signal-related kinase 1/2 (Erk1/2) pathway. Additionally, phosphatase and tensin homolog was upregulated and glycogen synthase kinase 3 beta was deactivated. Moreover, inactivation of signal transducer and activator of transcription 3 was detected following EHF inhibition, leading to inhibition of the epithelial-to-mesenchymal transition (EMT).

CONCLUSION

These results suggest that EHF plays a key role in cell proliferation, invasion, apoptosis, the cell cycle and EMT via the c-Met pathway. Therefore, EHF may serve as an antineoplastic target for the diagnosis and treatment of GC.

MET activation confers resistance to cetuximab, and prevents HER2 and HER3 upregulation in head and neck cancer

An understanding of the mechanisms underlying acquired resistance to cetuximab is urgently needed to improve cetuximab efficacy in patients with head and neck squamous cell carcinoma (HNSCC). Here, we present a clinical observation that MET pathway activation constitutes the mechanism of acquired resistance to cetuximab in a patient with HNSCC. Specifically, RNA sequencing and mass spectrometry analysis of cetuximab-sensitive (Cetux^Sen ) and cetuximab-resistant (Cetux^Res ) tumors indicated MET amplification and overexpression in the Cetux^Res tumor compared to the Cetux^Sen lesion. Stimulation of MET in HNSCC cell lines was sufficient to reactivate the MAPK pathway and to confer resistance to cetuximab in vitro and in vivo. In addition to the direct role of MET in reactivation of the MAPK pathway, MET stimulation abrogates the well-known cetuximab-induced compensatory feedback loop of HER2/HER3 expression. Mechanistically, we showed that the overexpression of HER2 and HER3 following cetuximab treatment is mediated by the ETS homologous transcription factor (EHF), and is suppressed by MET/MAPK pathway activation. Collectively, our findings indicate that evaluation of MET and HER2/HER3 in response to cetuximab in HNSCC patients can provide the rationale of successive line of treatment.

Increased expression of EHF contributes to thyroid tumorigenesis through transcriptionally regulating HER2 and HER3

E26 transformation-specific (ETS) transcription factor EHF plays a tumor suppressor role in prostate cancer and esophageal squamous cell carcinoma (ESCC), whereas it is overexpressed and may act as an oncogene in ovarian and mammary cancers. However, its biological role in thyroid cancer remains totally unknown. The aim of this study was to explore the biological functions of EHF and its potential as a therapeutic target in thyroid cancer. Using quantitative RT-PCR (qRT-PCR) assay, we evaluated mRNA expression of EHF in a cohort of primary papillary thyroid cancers (PTCs) and matched non-cancerous thyroid tissues. The functions of knockdown and ectopic expression of EHF in thyroid cancer cells were determine by a series of in vitro and in vivo experiments. Moreover, dual-luciferase reporter and chromatin immunoprecipitation (ChIP) assays were performed to identify its downstream targets. Our data showed that EHF expression was significantly increased in PTCs compared with matched non-cancerous thyroid tissues. EHF knockdown significantly inhibited thyroid cancer cell proliferation, colony formation, migration, invasion and tumorigenic potential in nude mice and induced cell cycle arrested and apoptosis by modulating the PI3K/Akt and MAPK/Erk signaling pathways. On the other hand, ectopic expression of EHF in thyroid cancer cells notably promoted cell growth and invasiveness. Importantly, EHF was identified as a new transcription factor for HER2 and HER3, contributing to thyroid tumorigenesis. Altogether, our findings suggest that EHF is a novel functional oncogene in thyroid cancer by transcriptionally regulating HER2 and HER3, and may represent a potential therapeutic target for this cancer.

miR‑206 inhibits cancer initiating cells by targeting EHF in gastric cancer

Cancer initiating cells (CIC) are defined as the unique subpopulation in the tumors that possess the ability to initiate tumor growth and sustain self-renewal as well as metastatic potential. In this study, we found that EHF overexpression promoted formation of CIC traits and silencing it inhibited the traits in gastric cancer NCI‑N87 cells. Overexpressing EHF downregulated the antitumor effect of 5-fluorouracil (5-FU) in NCI‑N87 cells. We found that miR‑206 downregulated EHF protein expression by targeting its 3'UTR in NCI‑N87 cells and GES-1 cells. Overexpressing miR‑206 inhibited formation of CIC in NCI‑N87 cells. In gastric cancer tissues, EHF protein expression was upregulated and miR‑206 was downregulated. We identified a negative correlation between EHF protein and miR‑206 expression in gastric cancer tissues. Thus, we concluded that miR‑206 inhibits formation of CICs by targeting EHF in gastric cancer.

The ETS family of oncogenic transcription factors in solid tumours

Findings over the past decade have identified aberrant activation of the ETS transcription factor family throughout all stages of tumorigenesis. Specifically in solid tumours, gene rearrangement and amplification, feed-forward growth factor signalling loops, formation of gain-of-function co-regulatory complexes and novel cis-acting mutations in ETS target gene promoters can result in increased ETS activity. In turn, pro-oncogenic ETS signalling enhances tumorigenesis through a broad mechanistic toolbox that includes lineage specification and self-renewal, DNA damage and genome instability, epigenetics and metabolism. This Review discusses these different mechanisms of ETS activation and subsequent oncogenic implications, as well as the clinical utility of ETS factors.

Increased expression of EHF via gene amplification contributes to the activation of HER family signaling and associates with poor survival in gastric cancer

The biological function of E26 transformation-specific (ETS) transcription factor EHF/ESE-3 in human cancers remains largely unknown, particularly gastric cancer. The aim of this study was to explore the role of EHF in tumorigenesis and its potential as a therapeutic target in gastric cancer. By using quantitative RT-PCR (qRT-PCR), immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) assays, we investigated the expression and copy number of EHF in a cohort of gastric cancers and control subjects. Specific EHF siRNAs was used to determine the biologic impacts and mechanisms of altered EHF expression in vitro and in vivo. Dual-luciferase reporter, chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift assay (EMSA) assays were performed to identify its downstream targets. Our results demonstrated that EHF was significantly upregulated and frequently amplified in gastric cancer tissues as compared with control subjects. Moreover, EHF amplification was positively correlated with its overexpression and significantly associated with poor clinical outcomes of gastric cancer patients. We also found that EHF knockdown notably inhibited gastric cancer cell proliferation, colony formation, migration, invasion and tumorigenic potential in nude mice and induced cell cycle arrest and apoptosis. Importantly, we identified EHF as a new HER2 transcription factor and the modulator of HER3 and HER4 in gastric cancer. Collectively, our findings suggest that EHF is a novel functional oncogene in gastric cancer by regulating the human epidermal growth factor receptor (HER) family of receptor tyrosine kinases and may represent a potential prognostic marker and therapeutic target for this cancer.

Identification of Transcription Factor-Gene Regulatory Network in Acute Myocardial Infarction

BACKGROUND

Acute myocardial infarction (AMI) is a common disease with serious mortality and morbidity, worldwide. The present study aimed to identify differentially expressed genes (DEGs) and construct a transcription factor-gene regulatory network to further study the early diagnosis of AMI.

METHODS

The integrated analysis of publicly available Gene Expression Omnibus datasets of AMI was performed. Differentially expressed genes were identified between AMI and normal blood samples. Gene Ontology enrichment analyses, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and the transcription factor-gene regulatory network were used to obtain insights into the functions of DEGs. Quantitative real-time polymerase chain reactions (qRT-PCR) were performed to validate the expression level of DEGs.

RESULTS

A total of 2,502 DEGs, including 917 up-regulated genes and 1,585 down-regulated genes, were identified between AMI and normal blood samples by integrating four expression profiles of AMI. Differentially expressed genes were significantly enriched in pathways including complement and coagulation cascades, Staphylococcus aureus infection, and cell adhesion molecules. Transcription factors were screened and performed to construct the regulatory network. The transcription factor-gene regulatory network consisted of 871 interactions between 80 transcription factors and 716 DEGs. ETS homologous factor (EHF) was one of transcription factors that had high connectivity with DEGs and regulated CACNB4 in the network. Verification by qRT-PCR revealed that EHF, KRT6A and DSG3 were significantly up-regulated, while CACNG4 was significantly down-regulated in AMI. Furthermore, CACNG6, CACNB4 and CLDN18 had a tendency to be down-regulated, and CALML3 had a tendency to be up-regulated in AMI.

CONCLUSIONS

The identification of important differentially expressed transcription factors and genes in the development of AMI would be the groundwork for the early diagnosis and early intervention of AMI.

Pre-analytical issues in effusion cytology

Effusions or body cavity fluids are amongst the most commonly submitted samples to the cytology laboratory. Knowledge of proper collection, storage, preservation and processing techniques is essential to ensure proper handling and successful analysis of the sample. This article describes how the effusions should be collected and proper conditions for submission. The different processing techniques to extract the cellular material and prepare slides satisfactory for microscopic evaluation are described such as direct smears, cytospins, liquid based preparations and cell blocks. The article further elaborates on handling the specimens for additional ancillary testing such as immunostaining and molecular tests, including predictive ones, as well as future research approaches.

Knockdown of EHF inhibited the proliferation, invasion and tumorigenesis of ovarian cancer cells

Ovarian cancer is the most lethal gynecologic malignancy worldwide. ETS homologous factor (EHF), a member of E26 transformation specific (ETS) transcription factors, has been reported overexpressed in ovarian cancer. However, the molecular mechanism underlying the biological function of EHF in ovarian cancer is still unclear. Here, we found that EHF was elevated in ovarian cancer tissues compared with non-tumorous tissues. Moreover, high EHF expression level was correlated with short survival time of patients with ovarian cancer. Knockdown of EHF in ovarian cancer cells, SKOV3 and OVCAR3, significantly inhibited cell proliferation and increased cells population in G1 phase. The proteins promoting cell cycles (Cyclin B1, Cyclin D1, and PCNA) were down-regulated and the protein negatively regulating cell cycle progression (P21) was up-regulated after EHF knockdown. Moreover, inhibition of EHF in ovarian cancer cells dramatically induced cell apoptosis, but impaired cell adhesion and cell invasion. Furthermore, phosphorylation levels of ERK and AKT were notably reduced in EHF knockdown cells. Finally, in vivo data showed that knockdown of EHF inhibited tumor growth in nude mice. Our data indicates that EHF could be a potential prognosis marker for ovarian cancer and work as an oncogene by targeting ERK and AKT signaling, which can serve as a new target for ovarian cancer treatment. © 2015 Wiley Periodicals, Inc.

Keratoacanthoma and squamous cell carcinoma are distinct from a molecular perspective

Keratoacanthoma is a controversial entity. Some consider keratoacanthoma as a variant of squamous cell carcinoma, whereas others see it as a distinct self-resolving squamoproliferative lesion. Our objective is to examine the relationship of keratoacanthoma with squamous cell carcinoma and normal skin by using DNA microarrays. DNA microarray studies were performed on formalin-fixed and paraffin-embedded blocks from ten cases of actinic keratoacanthoma utilizing the U133plus2.0 array. These results were compared with our previously developed microarray database of ten squamous cell carcinoma and ten normal skin samples. Keratoacanthoma demonstrated 1449 differentially expressed genes in comparison with squamous cell carcinoma (>5-fold change: P<0.01) with 908 genes upregulated and 541 genes downregulated. Keratoacanthoma showed 2435 differentially expressed genes in comparison with normal skin (>5-fold change: P<0.01) with 1085 genes upregulated and 1350 genes downregulated. The most upregulated genes, comparing keratoacanthoma with normal skin included MALAT1, S100A8, CDR1, TPM4, and CALM1. The most downregulated genes included SCGB2A2, DCD, THRSP, ADIPOQ, adiponectin, and ADH1B. The molecular biological pathway analysis comparing keratoacanthoma with normal skin showed that cellular development, cellular growth and proliferation, cell death/apoptosis, and cell cycle pathways are prominently involved in the pathogenesis of keratoacanthoma. The most enriched canonical pathways were clathrin-mediated endocytosis signaling, molecular mechanisms of cancer and integrin signaling. The distinctive gene expression profile of keratoacanthoma reveals that it is molecularly distinct from squamous cell carcinoma. The molecular pathways and genes differentially expressed in comparing keratoacanthoma with normal skin suggest that keratoacanthoma is a neoplasm that can regress due to upregulation of the cell death/apoptosis pathway.

miR-203 downregulates Yes-1 and suppresses oncogenic activity in human oral cancer cells

The purpose of this study was to elucidate the molecular mechanisms of microRNA-203 (miR-203) as a tumor suppressor in KB human oral cancer cells. MicroRNA microarray results showed that the expression of miR-203 was significantly down-regulated in KB cells compared with normal human oral keratinocytes. The viability of KB cells was decreased by miR-203 in the time- and dose-dependent manners. In addition, over-expressed miR-203 not only increased the nuclear condensation but also significantly increased the apoptotic population of KB cells. These results indicated that the over-expression of miR-203 induced apoptosis of KB cells. Furthermore, the target gene array analyses revealed that the expression of Yes-1, a member of the Src family kinases (SFKs), was significantly down-regulated by miR-203 in KB cells. Moreover, both the mRNA and protein levels of Yes-1 were strongly reduced in KB cells transfected with miR-203. Therefore, these results indicated that Yes-1 is predicted to be a potential target gene of miR-203. Through a luciferase activity assay, miR-203 was confirmed to directly targets the Yes-1 3' untranslated region (UTR) to suppress gene expression. Therefore, our findings indicate that miR-203 induces the apoptosis of KB cells by directly targeting Yes-1, suggesting its application in anti-cancer therapeutics.

Prediction of resistance to chemotherapy in ovarian cancer: a systematic review

Background

Patient response to chemotherapy for ovarian cancer is extremely heterogeneous and there are currently no tools to aid the prediction of sensitivity or resistance to chemotherapy and allow treatment stratification. Such a tool could greatly improve patient survival by identifying the most appropriate treatment on a patient-specific basis.

Methods

PubMed was searched for studies predicting response or resistance to chemotherapy using gene expression measurements of human tissue in ovarian cancer.

Results

42 studies were identified and both the data collection and modelling methods were compared. The majority of studies utilised fresh-frozen or formalin-fixed paraffin-embedded tissue. Modelling techniques varied, the most popular being Cox proportional hazards regression and hierarchical clustering which were used by 17 and 11 studies respectively. The gene signatures identified by the various studies were not consistent, with very few genes being identified by more than two studies. Patient cohorts were often noted to be heterogeneous with respect to chemotherapy treatment undergone by patients.

Conclusions

A clinically applicable gene signature capable of predicting patient response to chemotherapy has not yet been identified. Research into a predictive, as opposed to prognostic, model could be highly beneficial and aid the identification of the most suitable treatment for patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1101-8) contains supplementary material, which is available to authorized users.

Poly (ADP-ribose) polymerase 1 transcriptional regulation: a novel crosstalk between histone modification H3K9ac and ETS1 motif hypomethylation in BRCA1-mutated ovarian cancer

Poly (ADP-ribose) polymerase 1 (PARP1) plays a critical role in ovarian cancer progression. However, the epigenetic mechanism regulating PARP1 transcription remains largely unknown. Here, we show that the hypomethylated ETS1 motif is a key regulatory element for the PARP1 gene in BRCA1-mutated ovarian cancer. Mechanistically, the ETS1 motif hypomethylation-mediated increase of active histone marker H3K9ac and transcription factor ETS1 enrichment synergistically activates PARP1 transcription. Clinicopathological data indicate that a hypomethylated ETS1 motif was associated with high-grade tumors (P = 0.026) and pN1 (P = 0.002). Univariate survival analysis demonstrated an association between the hypomethylated ETS1 motif and an increased risk of death in BRCA1-mutated ovarian cancer patients. Our findings imply that the genetic (such as BRCA1 mutation) and epigenetic mechanisms (such as hypomethylated ETS1 motif, and histone modification H3K9ac and transcription factor ETS1 binding) are jointly involved in the malignant progression of PARP1-related ovarian cancer.

APOA1 mRNA expression in ovarian serous carcinoma effusions is a marker of longer survival

OBJECTIVES

We previously described the overexpression of APOA1 and GPX3 in ovarian/peritoneal serous carcinoma compared with breast carcinoma effusions using gene expression array analysis. The objective of the present study was to validate this finding and to analyze the association between these genes and clinicopathologic parameters, including survival, in advanced-stage ovarian serous carcinoma.

METHODS

APOA1 and GPX3 mRNA expression using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was analyzed in 121 effusions (101 ovarian, 20 breast carcinomas) and 85 solid ovarian carcinoma specimens (43 primary carcinomas, 42 metastases).

RESULTS

APOA1 and GPX3 transcript levels were significantly higher in ovarian carcinoma at all anatomic sites compared with breast carcinoma effusions (P < .001). GPX3 mRNA levels were significantly higher in primary carcinomas and solid metastases from patients who received neoadjuvant chemotherapy compared with chemo-naïve tumors (P = .016). APOA1 and GPX3 mRNA levels in the entire effusion series were unrelated to clinicopathologic parameters. However, higher APOA1 mRNA levels in primary diagnosis pre-chemotherapy effusions were significantly related to better overall survival (P = .045), a finding that retained its significance in Cox multivariate analysis (P = .016).

CONCLUSIONS

APOA1 and GPX3 mRNA levels on qRT-PCR effectively differentiate ovarian from breast carcinoma. APOA1 may be a novel prognostic marker in metastatic serous carcinoma.

Promoter hypomethylation, especially around the E26 transformation-specific motif, and increased expression of poly (ADP-ribose) polymerase 1 in BRCA-mutated serous ovarian cancer

BACKGROUND

Poly (ADP-ribose) polymerase 1 (PARP1) overexpression plays a critical role in ovarian cancer progression and the clinical development of PARP1 inhibitors to treat BRCA-mutated ovarian cancer has advanced rapidly. However, the mechanism regulating PARP1 expression remains unknown. Alterations in gene expression mediated by promoter methylation are being increasingly recognized and have frequently been reported in ovarian cancer. We therefore investigated the methylation status of the PARP1 promoter region and its correlation with PARP1 expression in BRCA-mutated ovarian cancer.

METHODS

DNA from BRCA-mutated serous ovarian cancer samples and adjacent normal ovarian tissues were analyzed by bisulfite sequence using primers focusing on the CpG island in the promoter region of PARP1. Expression levels of PARP1 were assessed by immunohistochemistry and real-time PCR.

RESULTS

Serous ovarian cancer tissues displayed decreased DNA methylation in the promoter region of PARP1 compared to normal tissue, and methylation intensity correlated inversely with PARP1 mRNA levels. More importantly, E26 transformation-specific (ETS) defined CpG sites were significantly less methylated in ovarian cancer samples.

CONCLUSIONS

These results indicate that hypomethylation of the promoter region, especially around the ETS motif might play a role in the upregulation of PARP1 expression in the progression of ovarian cancer.

AZGP1 and SPDEF mRNA expression differentiates breast carcinoma from ovarian serous carcinoma

The ANPEP, AZGP1, and SPDEF genes were previously found to be overexpressed in breast compared to ovarian carcinoma effusions. The present study validated this finding in a larger cohort consisting of both primary and metastatic tumors. ANPEP, AZGP1, and SPDEF mRNA expression was investigated in 83 breast carcinomas (57 primary carcinomas and 26 effusions) and 40 ovarian carcinomas (20 primary carcinomas and 20 effusions) using qPCR. ANPEP protein expression was immunohistochemically analyzed in 53 breast carcinoma effusions and patient-matched primary carcinomas (n = 25) and lymph node metastases (n = 16). mRNA and protein levels were studied for association with tumor type and anatomic site, and for clinical role in breast carcinoma. AZGP1 and SPDEF mRNA was overexpressed in breast compared to ovarian carcinoma (both p < 0.001). AZGP1 mRNA was overexpressed in primary breast carcinoma compared to effusions (p < 0.001), with opposite findings for ANPEP (p = 0.044). AZGP1 mRNA expression correlated with positive ER status (p = 0.032) and grade 1 histology (p = 0.011), whereas SPDEF mRNA levels were associated with positive ER (p = 0.002) and PR (p = 0.013) status and tamoxifen treatment (p = 0.004). ANPEP protein expression was higher in breast carcinoma effusions compared to primary tumors and lymph node metastases (both p = 0.001). ANPEP, AZGP1, and SPDEF levels were unrelated to disease-free or overall survival. This is the first study documenting ANPEP, AZGP1, and SPDEF expression in breast carcinoma effusions. AZGP1 and SPDEF may be novel molecular markers for the differentiation of breast from ovarian carcinoma. ANPEP may be involved in breast carcinoma progression in view of its overexpression in effusions compared to solid specimens.

Expression of ESE-3 isoforms in immunogenic and tolerogenic human monocyte-derived dendritic cells

Dendritic cells (DC) are the only hematopoietic cells expressing the epithelial specific Ets transcription factor ESE-3. Here we analyzed presence and quantity of isoforms ESE-3a, ESE-3b and ESE-3j in various immunogenic and tolerogenic human monocyte-derived DC (moDC) and blood DC populations using quantitative real time PCR and immunoblot analyses. ESE-3a and ESE-3b were detectable in all moDC populations with ESE-3b being the main transcript. ESE-3b expression was upregulated in immunogenic moDC and downregulated in tolerogenic moDC compared to immature moDC. ESE-3a had similar transcript levels in immature and immunogenic moDC and had very low levels in tolerogenic moDC. In blood DC populations only splice variant ESE-3b was detectable. ESE-3j was not detectable in any of the DC populations. These findings suggest that ESE-3b is the functionally most important ESE-3 isoform in DC.

Genes regulated in metastatic osteosarcoma: evaluation by microarray analysis in four human and two mouse cell line systems

Osteosarcoma (OS) is a rare bone neoplasm that affects mainly adolescents. It is associated with poor prognosis in case of metastases formation. The search for metastasis predicting markers is therefore imperative to optimize treatment strategies for patients at risk and important for the search of new drugs for the treatment of this devastating disease. Here, we have analyzed by microarray the differential gene expression in four human and two mouse OS cell line systems consisting of parental cell lines with low metastatic potential and derivatives thereof with increased metastatic potential. Using two osteoblastic cell line systems, the most common OS phenotype, we have identified forty-eight common genes that are differentially expressed in metastatic cell lines compared to parental cells. The identified subset of metastasis relevant genes in osteoblastic OS overlapped only minimally with differentially expressed genes in the other four preosteoblast or nonosteoblastic cell line systems. The results imply an OS phenotype specific expression pattern of metastasis regulating proteins and form a basis for further investigation of gene expression profiles in patients' samples combined with survival analysis with the aim to optimize treatment strategies to develop new drugs and to consequently improve the survival of patients with the most common form of osteoblastic OS.

PRAME (preferentially expressed antigen of melanoma) is a novel marker for differentiating serous carcinoma from malignant mesothelioma

The PRAME (preferentially expressed antigen of melanoma) gene was previously shown to be overexpressed in ovarian/primary peritoneal serous carcinoma compared with malignant mesothelioma using gene expression arrays. The objective of this study was to validate this finding at the messenger RNA (mRNA) and protein levels. Quantitative real-time polymerase chain reaction analysis of 126 müllerian carcinomas and 23 malignant mesotheliomas showed significantly higher PRAME mRNA expression in the former tumor (P < .001; test sensitivity and specificity, 89% and 91%, respectively). PRAME protein was expressed in 41 of 50 müllerian carcinomas and 0 of 30 mesotheliomas using Western blotting (P < .001; test sensitivity and specificity, 82% and 100%, respectively). PRAME levels in müllerian carcinoma were unrelated to survival; however, PRAME protein expression was up-regulated in solid metastases compared with primary carcinoma and effusions (P < .001). Our data confirm that PRAME effectively differentiates müllerian carcinoma from malignant mesothelioma at the mRNA and protein levels, suggesting a role in the diagnostic workup of serosal cancers.