Oestrogen receptor 1 mRNA is a prognostic factor in ovarian cancer patients treated with neo-adjuvant chemotherapy: determination by array and kinetic PCR in fresh tissue biopsies

An overview on Estrogen receptors signaling and its ligands in breast cancer

Estrogen governs the regulations of various pathological and physiological actions throughout the body in both males and females. Generally, 17β-estradiol an endogenous estrogen is responsible for different health problems in pre and postmenopausal women. The major activities of endogenous estrogen are executed by nuclear estrogen receptors (ERs) ERα and ERβ while non-genomic cytoplasmic pathways also govern cell growth and apoptosis. Estrogen accomplished a fundamental role in the formation and progression of breast cancer. In this review, we have hyphenated different studies regarding ERs and a thorough and detailed study of estrogen receptors is presented. This review highlights different aspects of estrogens ranging from receptor types, their isoforms, structures, signaling pathways of ERα, ERβ and GPER along with their crystal structures, pathological roles of ER, ER ligands, and therapeutic strategies to overcome the resistance.

miR-9-5p facilitates hepatocellular carcinoma cell proliferation, migration and invasion by targeting ESR1

The study aimed to explore the relationship between miR-9-5p and ESR1, and clarify the underlying functional mechanism in the occurrence and development of hepatocellular carcinoma (HCC). Expression data including miRNAs and mRNAs of HCC downloaded from TCGA database were processed for differential analysis, and corresponding clinical data were collected for survival analysis to identify the target miRNA miR-9-5p. Bioinformatics databases were applied for predicting downstream target mRNAs of miR-9-5p. qRT-PCR was used to evaluate expression of miR-9-5p. Western blot was used to detect protein expression of ESR1. MTT, wound healing assay and Transwell assay were used to detect HCC cell proliferation, migration and invasion, respectively. Dual-luciferase reporter gene assay was used to identify the targeting relationship between miR-9-5p and ESR1. Research suggested that miR-9-5p was highly expressed in HCC cells but ESR1 was poorly expressed. Overexpression of miR-9-5p could improve the proliferation, invasion and migration of cells. Dual-luciferase reporter assay showed that ESR1 was the downstream target of miR-9-5p in HCC. Overexpression of miR-9-5p markedly reduced ESR1 mRNA and protein levels in HCC cells, whereas inhibition of miR-9-5p expression produced the contrary results. Silencing ESR1 could noticeably reverse the effect of miR-9-5p knockdown on the proliferation, migration and invasion of HCC cells. As an oncogene, miR-9-5p fostered the proliferation, migration and invasion of HCC cells by targeting and inhibiting ESR1 expression.

Correlation between estrogen receptor expression and prognosis in epithelial ovarian cancer: a meta-analysis

OBJECTIVE

Accumulated studies have investigated the prognostic significance of estrogen receptor expression in epithelial ovarian cancer, but results remain controversial. The aim of this study was to perform a meta-analysis to clarify the prognostic value of estrogen receptor expression in epithelial ovarian cancer.

METHODS

A systematic search was performed in PUBMED, EMBASE, and COCHRANE databases to identify relevant studies up to December 2016. The pooled hazard rates (HR) with 95% confidence intervals (CIs) for overall survival and time to tumor progression were calculated and then weighted and pooled in this meta-analysis with a random-effect model.

RESULTS

Thirty-five studies with a total of 5824 patients were included. In brief, the expression of estrogen receptor was associated with an improved overall survival (HR = 0.86, 95% CI = 0.76-0.97), whereas there was no significant difference between estrogen receptor and time to tumor progression among epithelial ovarian cancer patients. Subgroup analysis revealed that estrogen receptor expression was significantly correlated with overall survival in different subgroups, such as in unclassified epithelial ovarian cancer (HR= 0.80, 95% CI = 0.66-0.95), studies using immunohistochemistry detection method (HR= 0.85, 95% CI = 0.73-1.00), European population (HR= 0.75, 95% CI = 0.60-0.94) and estrogen receptor α subtype (HR= 0.78, 95% CI = 0.62-0.98).

CONCLUSIONS

Estrogen receptor, especially estrogen receptor α, was associated with an improved overall survival in epithelial ovarian cancer. Estrogen receptor expression may be a promising prognostic factor in epithelial ovarian cancer patients.

Identifying candidate drivers of drug response in heterogeneous cancer by mining high throughput genomics data

BACKGROUND

With advances in technologies, huge amounts of multiple types of high-throughput genomics data are available. These data have tremendous potential to identify new and clinically valuable biomarkers to guide the diagnosis, assessment of prognosis, and treatment of complex diseases, such as cancer. Integrating, analyzing, and interpreting big and noisy genomics data to obtain biologically meaningful results, however, remains highly challenging. Mining genomics datasets by utilizing advanced computational methods can help to address these issues.

RESULTS

To facilitate the identification of a short list of biologically meaningful genes as candidate drivers of anti-cancer drug resistance from an enormous amount of heterogeneous data, we employed statistical machine-learning techniques and integrated genomics datasets. We developed a computational method that integrates gene expression, somatic mutation, and copy number aberration data of sensitive and resistant tumors. In this method, an integrative method based on module network analysis is applied to identify potential driver genes. This is followed by cross-validation and a comparison of the results of sensitive and resistance groups to obtain the final list of candidate biomarkers. We applied this method to the ovarian cancer data from the cancer genome atlas. The final result contains biologically relevant genes, such as COL11A1, which has been reported as a cis-platinum resistant biomarker for epithelial ovarian carcinoma in several recent studies.

CONCLUSIONS

The described method yields a short list of aberrant genes that also control the expression of their co-regulated genes. The results suggest that the unbiased data driven computational method can identify biologically relevant candidate biomarkers. It can be utilized in a wide range of applications that compare two conditions with highly heterogeneous datasets.

Dynamic modulation of phosphoprotein expression in ovarian cancer xenograft models

Background

The dynamic changes that occur in protein expression after treatment of a cancer in vivo are poorly described. In this study we measure the effect of chemotherapy over time on the expression of a panel of proteins in ovarian cancer xenograft models. The objective was to identify phosphoprotein and other protein changes indicative of pathway activation that might link with drug response.

Methods

Two xenograft models, platinum-responsive OV1002 and platinum-unresponsive HOX424, were used. Treatments were carboplatin and carboplatin-paclitaxel. Expression of 49 proteins over 14 days post treatment was measured by quantitative immunofluorescence and analysed by AQUA.

Results

Carboplatin treatment in the platinum-sensitive OV1002 model triggered up-regulation of cell cycle, mTOR and DDR pathways, while at late time points WNT, invasion, EMT and MAPK pathways were modulated. Estrogen receptor-alpha (ESR1) and ERBB pathways were down-regulated early, within 24 h from treatment administration. Combined carboplatin-paclitaxel treatment triggered a more extensive response in the OV1002 model modulating expression of 23 of 49 proteins. Therefore the cell cycle and DDR pathways showed similar or more pronounced changes than with carboplatin alone. In addition to expression of pS6 and pERK increasing, components of the AKT pathway were modulated with pAKT increasing while its regulator PTEN was down-regulated early. WNT signaling, EMT and invasion markers were modulated at later time points. Additional pathways were also observed with the NFκB and JAK/STAT pathways being up-regulated. ESR1 was down-regulated as was HER4, while further protein members of the ERBB pathway were upregulated late. By contrast, in the carboplatin-unresponsive HOX 424 xenograft, carboplatin only modulated expression of MLH1 while carboplatin-paclitaxel treatment modulated ESR1 and pMET.

Conclusions

Thirteen proteins were modulated by carboplatin and a more robust set of changes by carboplatin-paclitaxel. Early changes included DDR and cell cycle regulatory proteins associating with tumor volume changes, as expected. Changes in ESR1 and ERBB signaling were also observed. Late changes included components of MAPK signaling, EMT and invasion markers and coincided in time with reversal in tumor volume reduction. These results suggest potential therapeutic roles for inhibitors of such pathways that may prolong chemotherapeutic effects.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2212-6) contains supplementary material, which is available to authorized users.

Genomic and transcriptomic plasticity in treatment-naive ovarian cancer

Intra-tumor heterogeneity is a hallmark of many cancers and may lead to therapy resistance or interfere with personalized treatment strategies. Here, we combined topographic mapping of somatic breakpoints and transcriptional profiling to probe intra-tumor heterogeneity of treatment-naïve stage IIIC/IV epithelial ovarian cancer. We observed that most substantial differences in genomic rearrangement landscapes occurred between metastases in the omentum and peritoneum versus tumor sites in the ovaries. Several cancer genes such as NF1, CDKN2A, and FANCD2 were affected by lesion-specific breakpoints. Furthermore, the intra-tumor variability involved different mutational hallmarks including lesion-specific kataegis (local mutation shower coinciding with genomic breakpoints), rearrangement classes, and coding mutations. In one extreme case, we identified two independent TP53 mutations in ovary tumors and omentum/peritoneum metastases, respectively. Examination of gene expression dynamics revealed up-regulation of key cancer pathways including WNT, integrin, chemokine, and Hedgehog signaling in only subsets of tumor samples from the same patient. Finally, we took advantage of the multilevel tumor analysis to understand the effects of genomic breakpoints on qualitative and quantitative gene expression changes. We show that intra-tumor gene expression differences are caused by site-specific genomic alterations, including formation of in-frame fusion genes. These data highlight the plasticity of ovarian cancer genomes, which may contribute to their strong capacity to adapt to changing environmental conditions and give rise to the high rate of recurrent disease following standard treatment regimes.

The validation of estrogen receptor 1 mRNA expression as a predictor of outcome in patients with metastatic non-small cell lung cancer

The prognostic role of estrogen receptors in lung cancer is not validated. Results from patients with early stage non-small lung cancer patients indicate a prognostic role of estrogen receptor 1 (ESR1) mRNA expression in these patients. Automated RNA extraction from paraffin and RT-quantitative PCR was used for evaluation of tumoral ESR1 and progesterone receptor (PGR) mRNA expression. The test cohort consisted of 31 patients with advanced or metastatic non-small cell lung cancer (NSCLC) patients, treated in a first-line registry trial. For validation, 53 patients from a randomized multicentre first-line study with eligible tumor samples were evaluated. There was no significant correlation of ESR1 expression with clinical characteristics. ESR1 high expression was of significant positive prognostic value in the training set with a median overall survival (OS) of 15.9 versus 6.2 months for high versus low ESR1 expression patients (p = 0.0498, HR 0.39). This could be confirmed in the validation cohort with a median OS of 10.9 versus 5.0 months in ESR1 high versus low patients, respectively (p = 0.0321, HR 0.51). In the multivariate analysis adjusted for histological subtype, gender, age and performance status, ESR1 expression remained an independent prognostic parameter for survival in both cohorts. In contrast to ESR1, PGR expression was not able to separate prognostic groups or to predict outcome significantly (for OS; p = 0.94). Our study shows that ESR1 mRNA as assessed by qPCR represents a reliable method for detecting ESR1 expression in NSCLC and that ESR1 expression is an independent prognostic factor in metastatic NSCLC.

Association of somatic DNA methylation variability with progression-free survival and toxicity in ovarian cancer patients

BACKGROUND

We have addressed whether inter-individual methylation variation in somatic (white blood cells, WBCs) DNA of ovarian cancer patients provides potential for prognostic and/or pharmacoepigenetic stratification.

PATIENTS AND METHODS

WBC DNA methylation was analysed by bisulphite pyrosequencing at ataxia telangiectasia mutated (ATM), estrogen receptor 1 (ESR1), progesterone receptor (PGR), mutL homologue 1 (MLH1), breast cancer susceptibility gene (BRCA1), secreted frizzled-related protein 1 (SFRP1), stratifin (SFN), retinoic acid receptor beta (RARB) loci and the repetitive element LINE1 in 880 SCOTROC1 trial patients [paclitaxel (Taxol)-carboplatin versus docetaxel (Taxotere)-carboplatin as primary chemotherapy for stage Ic-IV epithelial ovarian cancer].

RESULTS

We observed no significant associations (P < 0.005, after correction for multiple testing) for progression-free survival (PFS) using test and validation sets. However, we did identify mean SFN methylation associated with PFS (hazard ratio, HR = 1.01 per 1% increase in methylation, q = 0.028); particularly in the paclitaxel (HR = 1.01, q = 0.006), but not in the docetaxel arm in stratified analyses. Furthermore, higher methylation within the ESR1 gene was associated with CA125 response (odds ratio, OR = 1.06, q = 0.04) and with neuropathy (HR = 0.95, q = 0.002), but only in the paclitaxel arm of the trial.

CONCLUSIONS

This is the first study linking DNA methylation variability in WBC to clinical outcomes for any tumour type; the data generated on novel prognostic and pharmacoepigenetic DNA methylation biomarkers in the circulation now need independent further evaluation.

Prognostic and predictive value of estrogen receptor 1 expression in completely resected non-small cell lung cancer

Adjuvant chemotherapy (ACT) leads to a modest improvement in survival among patients with completely resected non-small cell lung cancer (NSCLC) but molecular predictors are still rare. Publicly available gene microarray, clinical and follow-up data from two different studies on early-stage NSCLC were used to determine the expression of estrogen receptor 1 (ESR1). Expression values were calculated against clinical and survival data in a training set (n = 138) and a test set (subpopulation from the adjuvant JBR.10 study) allowing the determination of the prognostic effect of ESR1 in the observational arm as well as the predictive effect of ESR1 regarding ACT. Data were well balanced in terms of ESR1 expression. ESR1 high expression was of significant positive prognostic value in the training set and this could be confirmed in the test set cohort (hazard ratio for overall survival 0.248, 95% confidence interval: 0.088-0.701; p = 0.008). Additionally, ESR1 low tumors showed a benefit from ACT in terms of 5-year survival (33.3% observation arm and 77.8% ACT arm; p = 0.003), whereas patients with ESR1 high tumors did not have any benefit from ACT (test of interaction p = 0.024). ESR1 is an independent positive prognostic factor for survival in early-stage NSCLC patients. Patients with ESR1 high tumors did not benefit from ACT.

Modulation of estrogenic action in clear cell carcinoma of the ovary (Review)

Two histologic types, clear cell carcinoma (CCC) and endometrioid adenocarcinoma (EAC), are the common histology in ovarian cancer patients who have associated endometriosis. However, both tumor types have distinct clinicopathological characteristics and molecular phenotypes. EAC is predominantly positive for estrogen receptor (ER), but CCC specifically exhibits lower ER expression. This study reviews the current understanding of the role of the ER information in the pathogenesis of CCC, as well as the English language literature for biochemical studies on ER expression and estrogenic action in CCC. The iron-mediated oxidative stress occurs due to repeated hemorrhage in endometriosis, then this compound oxidatively modifies genomic DNA and, subsequently, ER depletion may be observed. There are a number of factors that interfere with ER expression and estrogen activity, which include DNA methylation of the promoter region, histone deacetylation, heme and iron binding, chromatin remodeling and ubiquitin ligase activity. Loss of estrogen function may be a turning point in CCC progression and aggressiveness.

The different roles of ER subtypes in cancer biology and therapy

By eliciting distinct transcriptional responses, the oestrogen receptors (ERs) ERα and ERβ exert opposite effects on cellular processes that include proliferation, apoptosis and migration and that differentially influence the development and the progression of cancer. Perturbation of ER subtype-specific expression has been detected in various types of cancer, and the differences in the expression of ERs are correlated with the clinical outcome. The changes in the bioavailability of ERs in tumours, together with their specific biological functions, promote the selective restoration of their activity as one of the major therapeutic approaches for hormone-dependent cancers.

Combination of osteopontin and activated leukocyte cell adhesion molecule as potent prognostic discriminators in HER2- and ER-negative breast cancer

BACKGROUND

To analyse the discriminative impact of osteopontin (OPN) and activated leukocyte cell adhesion molecule (ALCAM), combined with human epidermal growth factor 2 (HER2) and oestrogen receptor (ER) in breast cancer.

METHODS

Osteopontin, ALCAM, HER2 and ER mRNA expression in breast cancer tissues of 481 patients were analysed (mRNA microarray analysis, kinetic RT-PCR). Hierarchical clustering was performed in training cohort A (N=100, adjuvant treatment) and validation cohorts B (N=200, no adjuvant treatment, low-risk) and C (N=181, adjuvant treatment, high-risk).

RESULTS

Negative/low ER and HER2, high OPN and low ALCAM mRNA expression helped to identify patients at particularly high risk, showing shorter DFS, P<0.001, and OAS, P=0.001. Although both validation cohorts showed diverse risk and treatment profiles, this marker constellation was concordantly associated with shorter DFS and OAS (P<0.001 and P=0.075 for cohort B and P=0.043 and P<0.001 for cohort C, respectively). In multivariate analysis, this algorithm was the main independent prognostic factor. Cohort B: DFS, P=0.0065, OAS, not significant; cohort C: DFS, P=0.026, OAS, P<0.001.

CONCLUSION

Activated leukocyte cell adhesion molecule and OPN mRNA expression has a strong discriminative impact on survival within cancer patients with low or negative expression of ER and HER2, so called 'high-risk' breast cancers, and might help in identifying patients who could benefit from new treatment approaches like targeted therapies in the adjuvant setting.

Vascular endothelial growth factor C mRNA expression is a prognostic factor in epithelial ovarian cancer as detected by kinetic RT-PCR in formalin-fixed paraffin-embedded tissue

Vascular endothelial growth factor C (VEGF-C) is a well described chemotactic and growth factor for lymphatic endothelial cells. Its inhibition leads to suppression of lymphatic and distant metastases in mouse models. In ovarian cancer, the relationship between VEGF-C expression and tumor behavior has not yet been determined by a quantitative method in vivo. Therefore, we used a new technique of RNA extraction from formalin-fixed paraffin-embedded tissue samples and determined the expression levels of VEGF-C mRNA in a study group of 97 ovarian cancer patients. Expression levels were correlated with clinicopathological features and patient survival. High VEGF-C expression was associated with worse overall (p = 0.0393) and progression-free (p = 0.0155) patient survival. In the subgroups of serous tumors and high-grade tumors, VEGF-C mRNA was still a negative indicator for patient survival (p = 0.0190 and 0.0311, respectively). A trend was observed among patients with high clinical stage (p = 0.0634). In multivariate survival analysis VEGF-C mRNA retained its prognostic influence on progression-free survival (p = 0.006, HR = 0.319 with a 95% confidence interval of 0.142-0.720). High VEGF-C expression was further associated with an increased residual tumor mass after primary cytoreductive surgery. We found no correlation of VEGF-C expression with tumor grade, FIGO stage, lymph node, or distant metastases. Our study demonstrates that high VEGF-C expression is associated with aggressive tumor behavior in ovarian cancer. mRNA extracted from paraffin-embedded tumor samples is suitable for VEGF-C gene expression studies.