Methylation Signature Implicated in Immuno-Suppressive Activities in Tubo-Ovarian High-Grade Serous Carcinoma

BACKGROUND

Better understanding of prognostic factors in tubo-ovarian high-grade serous carcinoma (HGSC) is critical, as diagnosis confers an aggressive disease course. Variation in tumor DNA methylation shows promise predicting outcome, yet prior studies were largely platform-specific and unable to evaluate multiple molecular features.

METHODS

We analyzed genome-wide DNA methylation in 1,040 frozen HGSC, including 325 previously reported upon, seeking a multi-platform quantitative methylation signature that we evaluated in relation to clinical features, tumor characteristics, time to recurrence/death, extent of CD8+ tumor-infiltrating lymphocytes (TIL), gene expression molecular subtypes, and gene expression of the ATP-binding cassette transporter TAP1.

RESULTS

Methylation signature was associated with shorter time to recurrence, independent of clinical factors (N = 715 new set, hazard ratio (HR), 1.65; 95% confidence interval (CI), 1.10-2.46; P = 0.015; N = 325 published set HR, 2.87; 95% CI, 2.17-3.81; P = 2.2 × 10-13) and remained prognostic after adjustment for gene expression molecular subtype and TAP1 expression (N = 599; HR, 2.22; 95% CI, 1.66-2.95; P = 4.1 × 10-8). Methylation signature was inversely related to CD8+ TIL levels (P = 2.4 × 10-7) and TAP1 expression (P = 0.0011) and was associated with gene expression molecular subtype (P = 5.9 × 10-4) in covariate-adjusted analysis.

CONCLUSIONS

Multi-center analysis identified a novel quantitative tumor methylation signature of HGSC applicable to numerous commercially available platforms indicative of shorter time to recurrence/death, adjusting for other factors. Along with immune cell composition analysis, these results suggest a role for DNA methylation in the immunosuppressive microenvironment.

IMPACT

This work aids in identification of targetable epigenome processes and stratification of patients for whom tailored treatment may be most beneficial.

Disparity of ovarian cancer survival between urban and rural settings

Objective

To determine if there is a difference in overall survival of patients with epithelial ovarian cancer in rural, urban, and metropolitan settings in the United States.

Methods

We performed a retrospective cohort study using 2004–2016 National Cancer Database (NCDB) data including high and low grade, stage I-IV disease. Bivariate analyses used Student’s t-test for continuous variables and χ² test for dichotomous variables. Kaplan-Meier curves estimated survival of patients based on location of residence, and univariate analyses using Cox proportional HR assessed survival based on baseline characteristics. Multivariate analysis was performed to account for significant covariates. Propensity score matching was used to validate the multivariate survival model. For all tests, p<0.05 was considered statistically significant.

Results

A total of 111 627 patients were included with a mean age of 62.5 years for metroolitan (range 18–90), 64.0 years for rural (range 19–90) and 63.2 years for urban areas (range 18–90). Of all patients included, 94 290 were in a metropolitan area (counties >1 million population or 50 000–999 999), 15 386 were in an urban area (population of 10 000–49 999), and 1951 were in a rural area (non-metropolitan/non-core population). Univariate Cox proportional hazards models showed clinically significant differences in survival in patients from metropolitan, urban, and rural areas. Multivariate Cox proportional hazards models showed a clinically significant increase in HRs for patients in rural settings (HR 1.17; 95% CI 1.06 to 1.29). Increasing age and stage, non-insured status, non-white race, and comorbidity were also significant for poorer survival.

Conclusion

Patients with ovarian cancer who live in rural settings with small populations and greater distance to tertiary care centers have poorer survival. These differences hold after controlling for stage, age, and other significant risk factors related to poorer outcomes. To improve clinical outcomes, we need further studies to identify which of these factors are actionable.

Identification of Novel Fusion Transcripts in High Grade Serous Ovarian Cancer

Fusion genes are structural chromosomal rearrangements resulting in the exchange of DNA sequences between genes. This results in the formation of a new combined gene. They have been implicated in carcinogenesis in a number of different cancers, though they have been understudied in high grade serous ovarian cancer. This study used high throughput tools to compare the transcriptome of high grade serous ovarian cancer and normal fallopian tubes in the interest of identifying unique fusion transcripts within each group. Indeed, we found that there were significantly more fusion transcripts in the cancer samples relative to the normal fallopian tubes. Following this, the role of fusion transcripts in chemo-response and overall survival was investigated. This led to the identification of fusion transcripts significantly associated with overall survival. Validation was performed with different analytical platforms and different algorithms to find fusion transcripts.

Creation and validation of models to predict response to primary treatment in serous ovarian cancer

Nearly a third of patients with high-grade serous ovarian cancer (HGSC) do not respond to initial therapy and have an overall poor prognosis. However, there are no validated tools that accurately predict which patients will not respond. Our objective is to create and validate accurate models of prediction for treatment response in HGSC. This is a retrospective case–control study that integrates comprehensive clinical and genomic data from 88 patients with HGSC from a single institution. Responders were those patients with a progression-free survival of at least 6 months after treatment. Only patients with complete clinical information and frozen specimen at surgery were included. Gene, miRNA, exon, and long non-coding RNA (lncRNA) expression, gene copy number, genomic variation, and fusion-gene determination were extracted from RNA-sequencing data. DNA methylation analysis was performed. Initial selection of informative variables was performed with univariate ANOVA with cross-validation. Significant variables (p < 0.05) were included in multivariate lasso regression prediction models. Initial models included only one variable. Variables were then combined to create complex models. Model performance was measured with area under the curve (AUC). Validation of all models was performed using TCGA HGSC database. By integrating clinical and genomic variables, we achieved prediction performances of over 95% in AUC. Most performances in the validation set did not differ from the training set. Models with DNA methylation or lncRNA underperformed in the validation set. Integrating comprehensive clinical and genomic data from patients with HGSC results in accurate and robust prediction models of treatment response.

Prediction of Epithelial Ovarian Cancer Outcomes With Integration of Genomic Data

Some of the patients with epithelial ovarian cancer will not respond to initial therapy. These patients have a poor prognosis. Our aim was to identify patients with a worse prognosis by integrating clinical, pathologic, and genomic data. Using publicly available genomic data and integrating it with clinical data, we significantly improved the prediction of patients with worse surgical outcomes and those who do not respond to initial chemotherapy. We further improved these models with more precise data collection and better understanding of the genetic background of the studied population. Better prediction will lead to better patient classification and opportunities for individualized treatment.

Abstract PO032: Bacterial, archaea and viral transcripts (BAVT) expression in endometrial cancer

Objectives: Microbes are found virtually everywhere, including the human body. High-throughput sequencing of microbial genome, also known as metagenomic sequencing, may help to understand interactions between human and microbial processes. In this pilot study we aimed to determine differences of bacterial, archaea and viral expression between normal fallopian tube samples and ovarian and endometrial cancer samples. Then, we assessed these differentially expressed transcripts in endometrial and ovarian cancer from TCGA data. Methods: RNA was extracted and sequenced from 62 endometrial cancers, 104 high-grade serous ovarian cancers and 12 normal tubes specimens from our Biobank repository. Sequencing was performed using the Illumina HiSeq4000 platform that sequences 150 bp paired-end transcripts. Reads were processed with Centrifuge, a novel algorithm that classifies metagenomic sequences. We built our own index to differentiate between bacterial, archaea, viral and human transcripts. Resulting number of transcripts were normalized, log transformed and compared between tubal epithelium and ovarian and endometrial cancers (t-test). Lasso regression was used to identify significant independent transcripts between samples. TCGA ovarian and endometrial samples were processed as previously, and expression of significant probes were evaluated. Results: Bacterial, archaea and viral transcripts (BAVT) were 4.7% and 3,1% of all transcriptome in tubal and ovarian cancer respectively. 266 transcripts were differentially expressed between normal tubes and ovarian and endometrial cancer, with a p&lt;0.005. 11 bacteria and 1 virus were independently significant in the multivariate regression model. These microbes were mapped close to genome regulatory areas. In general, there were more BVAT in normal tube samples. The amount of BAVT decreased in endometrial cancer and even more in ovarian cancer, supporting this regulatory role of BAVT. BAVTs in TCGA were 0.8% of all transcriptome. Conclusions: BAVT expression is different between normal tissues and cancers in the gynecologic tract. Cancer amount of BAVT seems to decrease in malignant tissues, supporting a regulatory role of BAVT. Further studies are needed to determine the significance of BAVT amount and change of expression.

Citation Format: Silvana Pedra Nobre, Nicholas Cardillo, David Bender, Michael Goodheart, Eric Devor, Jesus Gonzalez Bosquet. Bacterial, archaea and viral transcripts (BAVT) expression in endometrial cancer [abstract]. In: Proceedings of the AACR Virtual Special Conference: Endometrial Cancer: New Biology Driving Research and Treatment; 2020 Nov 9-10. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(3_Suppl):Abstract nr PO032.

Association of a novel endometrial cancer biomarker panel with prognostic risk, platinum insensitivity, and targetable therapeutic options

During the past decade, the age-adjusted mortality rate for endometrial cancer (EC) increased 1.9% annually with TP53 mutant (TP53-mu) EC disproportionally represented in advanced disease and deaths. Therefore, we aimed to assess pivotal molecular parameters that differentiate clinical outcomes in high- and low-risk EC. Using the Cancer Genome Atlas, we analyzed EC specimens with available DNA sequences and quantitative gene-specific RNA expression data. After polymerase ɛ (POLE)-mutant specimens were excluded, differential gene-specific mutations and mRNA expressions were annotated and integrated. Consequent to TP53-mu failure to induce p21, derepression of multiple oncogenes harboring promoter p21 repressive sites was observed, including CCNA2 and FOXM1 (P < .001 compared with TP53 wild type [TP53-wt]). TP53-wt EC with high CCNA2 expression (CCNA2-H) had a targeted transcriptomic profile similar to that of TP53-mu EC, suggesting CCNA2 is a seminal determinant for both TP53-wt and TP53-mu EC. CCNA2 enhances E2F1 function, upregulating FOXM1 and CIP2A, as observed in TP53-mu and CCNA2-H TP53-wt EC (P < .001). CIP2A inhibits protein phosphatase 2A, leading to AKT inactivation of GSK3β and restricted oncoprotein degradation; PPP2R1A and FBXW7 mutations yield similar results. Upregulation of FOXM1 and failed degradation of FOXM1 is evidenced by marked upregulation of multiple homologous recombination genes (P < .001). Integrating these molecular aberrations generated a molecular biomarker panel with significant prognostic discrimination (P = 5.8×10⁻⁷); adjusting for age, histology, grade, myometrial invasion, TP53 status, and stage, only CCNA2-H/E2F1-H (P = .0003), FBXW7-mu/PPP2R1A-mu (P = .0002), and stage (P = .017) were significant. The generated prognostic molecular classification system identifies dissimilar signaling aberrations potentially amenable to targetable therapeutic options.

Interval debulking surgery is not worth the wait: a National Cancer Database study comparing primary cytoreductive surgery versus neoadjuvant chemotherapy

Objective

In previous studies, neoadjuvant chemotherapy followed by interval debulking surgery was not inferior to primary cytoreductive surgery as initial treatment for advanced epithelial ovarian cancer. Our study aimed to compare surgical and survival outcomes between the two treatments in a large national database.

Methods

Data were extracted from the National Cancer Database from January 2004 to December 2015. Patients with FIGO (International Federation of Gynecologists and Obstetricians) stage III-IV epithelial ovarian cancer and known sequence of treatment were included: primary cytoreductive (surgery=26 717 and neoadjuvant chemotherapy=9885). Tubal and primary peritoneal cancer diagnostic codes were not included. Residual disease after treatment was defined based on recorded data: R0 defined as microscopic or no residual disease; R1 defined as macroscopic residual disease. Multivariate Cox proportional HR was used for survival analysis. Multivariate logistic regression analysis was utilized to compare mortality between groups. Outcomes were adjusted for significant covariates. Validation was performed using propensity score matching of significant covariates.

Results

A total of 36 602 patients were included in the analysis. Patients who underwent primary cytoreductive surgery had better survival than those treated with neoadjuvant chemotherapy followed by interval surgery, after adjusting for age, co-morbidities, stage, and residual disease (p<0.001). Primary cytoreductive surgery patients with R0 disease had best median survival (62.6 months, 95% CI 60.5–64.5). Neoadjuvant chemotherapy patients with R1 disease had worst median survival (29.5 months, 95% CI 28.4–31.9). There were small survival differences between primary cytoreductive surgery with R1 (38.9 months) and neoadjuvant chemotherapy with R0 (41.8 months) (HR 0.93, 95% CI 0.87 to 1.0), after adjusting for age, co-morbidities, grade, histology, and stage. Neoadjuvant chemotherapy had 3.5 times higher 30-day mortality after surgery than primary cytoreductive surgery (95% CI 2.46 to 5.64). The 90-day mortality was higher for neoadjuvant chemotherapy in multivariate analysis (HR 1.31, 95% CI 1.06 to 1.61) but similar to primary cytoreductive surgery after excluding high-risk patients.

Conclusions

Most patients with advanced epithelial ovarian cancer may benefit from primary cytoreductive surgery. Patients treated with neoadjuvant chemotherapy should be those with co-morbidities unfit for surgery.

A Prediction Model for Preoperative Risk Assessment in Endometrial Cancer Utilizing Clinical and Molecular Variables

The utility of comprehensive surgical staging in patients with low risk disease has been questioned. Thus, a reliable means of determining risk would be quite useful. The aim of our study was to create the best performing prediction model to classify endometrioid endometrial cancer (EEC) patients into low or high risk using a combination of molecular and clinical-pathological variables. We then validated these models with publicly available datasets. Analyses between low and high risk EEC were performed using clinical and pathological data, gene and miRNA expression data, gene copy number variation and somatic mutation data. Variables were selected to be included in the prediction model of risk using cross-validation analysis; prediction models were then constructed using these variables. Model performance was assessed by area under the curve (AUC). Prediction models were validated using appropriate datasets in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. A prediction model with only clinical variables performed at 88%. Integrating clinical and molecular data improved prediction performance up to 97%. The best prediction models included clinical, miRNA expression and/or somatic mutation data, and stratified pre-operative risk in EEC patients. Integrating molecular and clinical data improved the performance of prediction models to over 95%, resulting in potentially useful clinical tests.

Abstract 3619: Role of MTDH in estrogen-regulated gene expression

Disruption of estrogen signaling is widely associated with the development of breast, endometrial, and ovarian cancers. As a multifunctional mediator of carcinogenesis, metadherin (MTDH)/AEG-1 overexpression has been associated with numerous types of cancers, with reported roles in tumor initiation, proliferation, invasion, metastasis and chemoresistance. At the molecular level, MTDH has been shown to interact with proteins that drive tumorigenesis, including NF-κB, PLZF, BCCIPα and SND1. Through analysis of the Cancer Genome Atlas (TCGA) datasets for ER-positive endometrial and breast cancers, we found that over 25% of all gene expression correlated with MTDH. Using Affymetrix microarrays, we characterized the differences in gene expression between estrogen-treated parental and MTDH-deficient endometrial and breast cancer cells. We also explored a possible interaction between MTDH and ER by immunoprecipitation and found that MTDH and ER associated in both breast and endometrial cancer cells in response to estrogen. Reciprocal co-immunoprecipitation analysis demonstrated that acute estrogen stimulation promoted the interaction of MTDH with ER in the nucleus. These data suggest that MTDH and ERα interact in the nucleus with estrogen treatment, and MTDH/ER co-regulated genes may have functions in drug resistance, metastasis and tumor progression.

Citation Format: Xiangbing Meng, Yujun Li, Jesus Gonzalez Bosquet, shujie yang, Kristina W. Thiel, Kimberly K. Leslie. Role of MTDH in estrogen-regulated gene expression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3619. doi:10.1158/1538-7445.AM2017-3619

Role of metadherin in estrogen-regulated gene expression

The disruption of estrogen signaling is widely associated with the development of breast, endometrial and ovarian cancers. As a multifunctional mediator of carcinogenesis, metadherin (MTDH)/astrocyte elevated gene-1 (AEG-1) overexpression has been associated with numerous types of cancer, with reported roles in tumor initiation, proliferation, invasion, metastasis and chemoresistance. At the molecular level, MTDH has been shown to interact with proteins that drive tumorigenesis, including nuclear factor-κB (NF-κB), promyelocytic leukaemia zinc finger (PLZF), BRCA2- and CDKN1A (p21Cip1/Waf-1/mda-6)-interacting protein α (BCCIPα) and staphylococcal nuclease and tudor domain containing 1 (SND1). Through the analysis of the Cancer Genome Atlas (TCGA) datasets for estrogen receptor (ER)-positive endometrial and breast cancers, we found that over 25% of all gene expression correlated with MTDH. Using Affymetrix microarrays, we characterized the differences in gene expression between estrogen-treated parental and MTDH-deficient endometrial and breast cancer cells. We also explored a possible interaction between MTDH and ER by immunoprecipitation, and found that MTDH and ER associated in both breast and endometrial cancer cells in response to estrogen. Reciprocal co-immunoprecipitation analysis demonstrated that acute estrogen stimulation promoted the interaction of MTDH with ER in the nucleus. These data, to the best of our knowledge, provide the first evidence that MTDH and ERα interact in the nucleus with estrogen treatment to regulate gene expression.

Prediction of chemo-response in serous ovarian cancer

Background

Nearly one-third of serous ovarian cancer (OVCA) patients will not respond to initial treatment with surgery and chemotherapy and die within one year of diagnosis. If patients who are unlikely to respond to current standard therapy can be identified up front, enhanced tumor analyses and treatment regimens could potentially be offered. Using the Cancer Genome Atlas (TCGA) serous OVCA database, we previously identified a robust molecular signature of 422-genes associated with chemo-response. Our objective was to test whether this signature is an accurate and sensitive predictor of chemo-response in serous OVCA.

Methods

We first constructed prediction models to predict chemo-response using our previously described 422-gene signature that was associated with response to treatment in serous OVCA. Performance of all prediction models were measured with area under the curves (AUCs, a measure of the model’s accuracy) and their respective confidence intervals (CIs). To optimize the prediction process, we determined which elements of the signature most contributed to chemo-response prediction. All prediction models were replicated and validated using six publicly available independent gene expression datasets.

Results

The 422-gene signature prediction models predicted chemo-response with AUCs of ~70 %. Optimization of prediction models identified the 34 most important genes in chemo-response prediction. These 34-gene models had improved performance, with AUCs approaching 80 %. Both 422-gene and 34-gene prediction models were replicated and validated in six independent datasets.

Conclusions

These prediction models serve as the foundation for the future development and implementation of a diagnostic tool to predict response to chemotherapy for serous OVCA patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-016-0548-9) contains supplementary material, which is available to authorized users.

Stratification of endometrioid endometrial cancer patients into risk levels using somatic mutations

OBJECTIVE

Patients with endometrioid endometrial cancer are stratified as high risk and low risk for extrauterine disease by surgical staging. Since patients with low-grade, minimally invasive disease do not benefit from comprehensive staging, pre-surgery stratification into a risk category may prevent unnecessary surgical staging in low risk patients. Our objective was to develop a predictive model to identify risk levels using somatic mutations that could be used preoperatively.

METHODS

We classified endometrioid endometrial cancer patients in The Cancer Genome Atlas (TCGA) dataset into high risk and low risk categories: high risk patients presented with stage II, III or IV disease or stage I with high-intermediate risk features, whereas low risk patients consisted of the remaining stage I patients with either no myometrial invasion or low-intermediate risk features. Three strategies were used to build the prediction model: 1) mutational status for each gene; 2) number of somatic mutations for each gene; and 3) variant allele frequencies for each somatic mutation for each gene.

RESULTS

Each prediction strategy had a good performance, with an area under the curve (or AUC) between 61% and 80%. Analysis of variant allele frequency produced a superior prediction model for risk levels of endometrial cancer as compared to the other two strategies, with an AUC=91%. Lasso and Ridge methods identified 53 mutations that together had the highest predictability for high risk endometrioid endometrial cancer.

CONCLUSIONS

This prediction model will assist future retrospective and prospective studies to categorize endometrial cancer patients into high risk and low risk in the preoperative setting.

Differentially expressed genes in preimplantation human embryos: potential candidate genes for blastocyst formation and implantation

Purpose

The aim of this study was to determine which genes and gene pathways are differentially expressed when comparing human blastocysts with cleavage-stage embryos.

Methods

We individually assessed gene expression in preimplantation human embryos at cleavage (n = 3) and blastocyst (n = 3) stages. Gene expression patterns were then validated in publically available datasets and then independently validated in vitro with additional human embryos using TaqMan gene expression assays. Immunolocalization studies were conducted to identify protein expression in intact blastocyst-stage embryos.

Results

Compared to cleavage-stage embryos, blastocyst-stage embryos differentially expressed 51 genes (p < 0.001), with overrepresentation in amoebiasis pathways and pathways in cancer. Of these 51 genes, 21 were found to be independently validated in a separate, publically available dataset, with a substantial agreement with our initial findings (κ = 0.8). In an independent set of cleavage- and blastocyst-stage embryos, we validated that six of eight tested genes were differentially expressed (p < 0.05) by RT-qPCR. Immunofluorescence studies documented the presence of two studied proteins in the trophectoderm of blastocyst-stage embryos.

Conclusions

Differentially expressed genes may be implicated in the invasion and proliferation of the early embryo. Our research highlights specific genes that may be further studied for their role in the implantation process and additionally raises questions about localized gene and/or protein expression in the trophectoderm, which could affect protocols for, and interpretation of, trophectoderm biopsies performed in in vitro fertilization cycles.

Electronic supplementary material

The online version of this article (doi:10.1007/s10815-016-0745-x) contains supplementary material, which is available to authorized users.

Analysis of chemotherapeutic response in ovarian cancers using publicly available high-throughput data

A third of patients with epithelial ovarian cancer (OVCA) will not respond to standard treatment. The determination of a robust signature that predicts chemoresponse could lead to the identification of molecular markers for response as well as possible clinical implementation in the future to identify patients at risk of failing therapy. This pilot study was designed to identify biologic processes affecting candidate pathways associated with chemoresponse and to create a robust gene signature for follow-up studies. After identifying common pathways associated with chemoresponse in serous OVCA in three independent gene-expression experiments, we assessed the biologic processes associated with them using The Cancer Genome Atlas (TCGA) dataset for serous OVCA. We identified differential copy-number alterations (CNA), mutations, DNA methylation, and miRNA expression between patients that responded to standard treatment and those who did not or recurred prematurely. We correlated these significant parameters with gene expression to create a signature of 422 genes associated with chemoresponse. A consensus clustering of this signature identified two differentiated clusters with unique molecular patterns: cluster 1 was significant for cellular signaling and immune response (mainly cell-mediated); and cluster 2 was significant for pathways involving DNA-damage repair and replication, cell cycle, and apoptosis. Validation through consensus clustering was performed in five independent OVCA gene-expression experiments. Genes were located in the same cluster with consistent agreement in all five studies (κ coefficient ≥ 0.6 in 4). Integrating high-throughput biologic data have created a robust molecular signature that predicts chemoresponse in OVCA.

Comparison of gene expression patterns between avian and human ovarian cancers

OBJECTIVES

A putative model of spontaneous cancer has been described in the laying hen that bears significant similarities to human ovarian cancer. Our objective was to characterize and compare the patterns of gene expression in chicken and human forms of this disease.

METHODS

RNA from 20 localized and metastatic ovarian and oviductal chicken tumor samples was isolated, amplified using in vitro transcription, and hybridized against normal ovarian epithelium to a customized cDNA microarray constructed for these studies. Differentially expressed genes were identified for localized ovarian, metastatic ovarian, and oviductal (or tubal) cancer by class comparison using BRB-ArrayTools. Results were validated with semi-quantitative PCR. A gene list (prediction model) constructed with the class prediction tool was used in a human ovarian cancer microarray obtained from the GEO datasets (GSE6008) in order to compare these results across species.

RESULTS

Class comparison analysis between localized ovarian, metastatic ovarian and oviductal cancer yielded 41 different informative probes that coded for 27 unique genes. Localized ovarian samples clustered between metastatic ovarian and oviductal cancer samples. Using our chicken data as a training set and leaving oviductal samples out of the analysis, we created a prediction model that classified early stage and advanced stage human ovarian cancer gene expression arrays with 78% overall accuracy.

CONCLUSIONS

Gene expression of spontaneous ovarian cancer in the chicken is comparable to gene expression patterns of human ovarian cancer.

No association between FTO or HHEX and endometrial cancer risk

INTRODUCTION

Obesity and diabetes are known risk factors for endometrial cancer; thus, the genetic risk factors of these phenotypes might also be associated with endometrial cancer risk. To evaluate this hypothesis, we genotyped tag-single nucleotide polymorphisms (SNP) and candidate SNPs in FTO and HHEX in a primary set of 417 endometrial cancer cases and 406 population-based controls, and validated significant findings in a replication set of approximately 2,347 cases and 3,140 controls from three additional studies.

METHODS

We genotyped 189 tagSNPs in FTO (including rs8050136) and five tagSNPs in HHEX (including rs1111875) in the primary set and one SNP each in FTO (rs12927155) and HHEX (rs1111875) in the validation set. Per allele odds ratios (OR) and 95% confidence intervals (CI) were calculated to estimate the association between the genotypes of each SNPs (as an ordinal variable) and endometrial cancer risk using unconditional logistic regression models, controlling for age and site.

RESULTS

In the primary study, the most significant finding in FTO was rs12927155 (OR, 1.56; 95% CI, 1.21-2.01; P = 5.8 x 10(-4)), and in HHEX, it was rs1111875 (OR, 0.80; 95% CI, 0.66-0.97; P = 0.026). In the validation studies, the pooled per allele OR, adjusted for age and study for FTO, was rs12927155 (OR, 0.94; 95% CI, 0.83-1.06; P = 0.29), whereas for HHEX, it was rs1111875 (OR, 1.00; 95% CI, 0.92-1.10; P = 0.96).

CONCLUSION

Our data indicate that common genetic variants in two genes previously related to obesity (FTO) and diabetes (HHEX) by genome-wide association scans were not associated with endometrial cancer risk.

IMPACT

Polymorphisms in FTO and HHEX are unlikely to have large effects on endometrial cancer risk but may have weaker effects.

Common genetic variation in the sex hormone metabolic pathway and endometrial cancer risk: pathway-based evaluation of candidate genes

BACKGROUND

Estrogen plays a major role in endometrial carcinogenesis, suggesting that common variants of genes in the sex hormone metabolic pathway may be related to endometrial cancer risk. In support of this view, variants in CYP19A1 [cytochrome P450 (CYP), family 19, subfamily A, polypeptide 1] have been associated with both circulating estrogen levels and endometrial cancer risk. Associations with variants in other genes have been suggested, but findings have been inconsistent.

METHODS

We examined 36 sex hormone-related genes using a tagging approach in a population-based case-control study of 417 endometrial cancer cases and 407 controls conducted in Poland. We evaluated common variation in these genes in relation to endometrial cancer risk using sequential haplotype scan, variable-sized sliding window and adaptive rank-truncated product (ARTP) methods.

RESULTS

In our case-control study, the strongest association with endometrial cancer risk was for AR (androgen receptor; ARTP P = 0.006). Multilocus analyses also identified boundaries for a region of interest in AR and in CYP19A1 around a previously identified susceptibility loci. We did not find evidence for consistent associations between previously reported candidate single-nucleotide polymorphisms in this pathway and endometrial cancer risk.

DISCUSSION

In summary, we identified regions in AR and CYP19A1 that are of interest for further evaluation in relation to endometrial cancer risk in future haplotype and subsequent fine mapping studies in larger study populations.

Patterns of inguinal groin metastases in squamous cell carcinoma of the vulva

OBJECTIVES

Assess the pattern of groin node metastases in squamous cell carcinoma (SCC) of the vulva in relation to the site of the primary lesion. Assess whether the identified pattern of lymphatic spread supports the current surgical practice of assessing contralateral nodes for lateral lesions with ipsilateral nodal involvement.

METHODS

A retrospective study of surgically staged patients with primary SCC of the vulva between 1955 and 1990 was conducted. This cohort of patients was divided in 4 subgroups by location of primary lesion: unilateral, bilateral, midline, and patients with mediolateral lesions. All clinical and pathological data were reviewed and updated to the 1988 TNM vulvar classification.

RESULTS

320 patients met the inclusion criteria, and almost all of them (>95%) underwent bilateral groin assessment. Of the 108 patients with positive groin lymph-node (LN) involvement, 77 presented with unilateral and 24 with bilateral inguinofemoral involvement. Of the 163 patients presenting with only unilateral vulvar lesions, 48 had inguinofemoral node involvement: 37 with ipsilateral-only nodal metastases, 8 with bilateral LN invasion, and only 3 (1.8%) had isolated contralateral nodal metastases. None of these patients with unilateral vulvar lesion that was either < or = 2 cm in biggest diameter or with invasion < or = 5 mm had bilateral groin LN involvement at diagnosis.

CONCLUSIONS

Ipsilateral lymphadenectomy is suitable for patients with unilateral lesions, distant from the midline, and either negative ipsilateral nodes, or with positive ipsilateral LN with lesions smaller than 2 cm.

Hepatic resection for metachronous metastases from ovarian carcinoma

Recently, several authors have reported that optimal primary cytoreduction of both hepatic and extrahepatic disease is not only feasible but improves survival. However, the role of hepatic resection in combination with secondary cytoreduction for epithelial ovarian cancer is unclear. Patients with recurrent ovarian cancer and metachronous intrahepatic metastases are often evaluated by a multidisciplinary team at the Mayo Clinic comprising pelvic and hepatobiliary surgeons for consideration of cytoreductive surgery. The purpose of this report is to update the outcome of cytoreductive surgery including hepatic resection for patients with metastatic ovarian carcinoma.

Epigenetic-mediated upregulation of progesterone receptor B gene in endometrial cancer cell lines

OBJECTIVES

To determine if epigenetic interference can restore progesterone receptor-B (PR-B) expression in PR-B negative endometrial adenocarcinoma cell lines, and to characterize the kinetics of PR-B induction mediated by DNA methyltransferase and histone deacetylase inhibitors.

METHODS

The PR-B negative endometrioid cancer cell lines KLE and HEC-1B were used as study models. PR-B mRNA and protein expression levels were measured using real-time PCR and Western blot analysis, respectively. DNA methylation levels of the PR-B promoter were determined by methylation-specific PCR. Dose-response correlations and the duration of response to aza-deoxycytidine (ADC) and trichostatin A (TSA) were characterized. Cell responses to prolonged and repeated drug treatment were also examined.

RESULTS

Relatively low concentrations of ADC and TSA over a 24-h period induced PR-B expression. Furthermore, ADC and TSA acted synergistically to reactivate PR-B expression. Depending on the cell line used, PR-B mRNA was induced 10-110 fold. This elevated PR-B expression continued for 48 h after drug withdrawal. Sustained upregulation of PR-B mRNA and protein was observed during prolonged and repeated drug treatment.

CONCLUSION

The epigenetically silenced PR-B gene remains sensitive to changes in DNA demethylation and histone acetylation in uterine adenocarcinoma cell lines. Treatment with ADC and/or TSA results in a robust and sustainable PR-B upregulation. These small molecule epigenetic modifying agents may be used to sensitize poorly differentiated, PR-B negative endometrial cancers to progestational therapy.

Long-term survival and disease recurrence in patients with primary squamous cell carcinoma of the vulva

OBJECTIVES

To assess time to failure and sites of failure with extended follow-up of patients with squamous cell carcinoma (SCC) of the vulva.

METHODS

A retrospective analysis of 330 patients with primary SCC of the vulva treated at Mayo Clinic between 1955 and 1990 was conducted. The main outcome measures were the rates of treatment failure. The Kaplan-Meier method and the log-rank test were used to estimate the rates of overall survival, disease-free survival, and recurrence. The Cox proportional hazards model was used to assess independent variables as prognostic factors for treatment failure.

RESULTS

All 330 patients in the cohort underwent lymphadenectomy; 113 patients (34.2%) had involvement of the inguinofemoral nodes and 88 patients (26.7%) had treatment failure. Treatment failures occurred more frequently in patients who presented with inguinal metastasis at the primary surgery and during the first 2 years of follow-up. After 2 years, both groups, with or without positive inguinal nodes, had similar treatment failure rates. Most patients with disease recurrence in the groin died within the first 2 years of follow-up. Involvement of the inguinal nodes was the main independent predictive factor for survival, disease recurrence, and metastasis.

CONCLUSIONS

Most treatment failures occurred during the 2 years after initial surgical management. However, in 35% of patients, disease reoccurred 5 years or more after diagnosis, which demonstrates the need for long-term follow-up. Complete ipsilateral or bilateral inguinofemoral lymph node dissection ensures a thorough evaluation and treatment of the groin.

Cytokeratin staining of resected lymph nodes may improve the sensitivity of surgical staging for endometrial cancer

OBJECTIVE

The presence of metastases to regional lymph nodes (LN) is the single most important risk factor in endometrial cancer. Advances in molecular biology have provided more sensitive methods for detecting micrometastasis. This was a pilot study to determine whether cytokeratin staining of LN from endometrial cancer patients is more sensitive than traditional histopathologic evaluation for the detection of micrometastasis.

METHODS

The inclusion criteria included patients with surgical stage I-II endometrial cancer having >50% myometrial invasion, lesions >2 cm, and negative LN together with one of the following: FIGO grade 3 or cervical or lymph-vascular involvement. A matched control group included patients with LN metastasis. The evaluation of the LN at the time of initial surgery consisted of a frozen section and a reevaluation on permanent sections with H&E. In the study, lymphadenectomy specimens were cut, stained again with H&E and with cytokeratin, and examined. Cytokeratin staining was performed with AE1/AE3 antibodies. There were 16 LN-negative cases and 9 LN-positive controls.

RESULTS

There was complete agreement between the LN assessment at time of surgery and the study H&E review prior to the staining for cytokeratin. However, 2 LN-negative cases (12.5%) had micrometastasis by cytokeratin staining. One of these patients developed recurrent disease in the para-aortic LN and died of disease at 2.8 years.

CONCLUSION

Cytokeratin staining may improve the sensitivity for detection of metastasis compared to traditional evaluation. This study strongly suggests that these micrometastasis are clinically significant. An approach incorporating cytokeratin analysis could improve the risk assessment of specific patients.

Risk of occult inguinofemoral lymph node metastasis from squamous carcinoma of the vulva

PURPOSE

This study was undertaken to correlate preoperative primary tumor size and American Joint Committee on Cancer and International Federation of Gynecology and Obstetrics categories with the risk of subclinical metastases from squamous carcinoma of the vulva to inguinofemoral nodes in patients with a palpably negative groin preoperatively.

METHODS AND MATERIALS

Clinical notes, operative reports, and pathology reports from 1955 to 1990 were reviewed to assign retrospectively 1969 American Joint Committee on Cancer N(0) and N(1) and 1988 International Federation of Gynecology and Obstetrics T categories.

RESULTS

Of 446 patients with primary carcinoma of the vulva, 226 had a groin without features indicative of lymph node metastasis. Occult groin node metastases were detected in 15.2%, 30.0%, 24.5%, and 0% of patients with T(1), T(2), T(3), and T(4) cancers, respectively. Subclinical node metastases were found in 7.0%, 22.2%, 26.9%, 34.1%, and 20.0% of patients with primary cancers measuring 1.0 cm or less, 1.1 to 2.0 cm, 2.1 to 3.0 cm, 3.1 to 5.0 cm, and larger than 5 cm, respectively.

CONCLUSIONS

Efficacy assessment for elective groin node irradiation and quantitative description of the radiation dose-control relationship for subclinical disease should be based on estimates of the risk of subclinical disease within the target volume. This study may help to assess the effectiveness of current therapies.

Small bowel obstruction associated with post-hysterectomy vaginal vault prolapse

BACKGROUND

Patients may present with post-hysterectomy vaginal vault prolapse in conjunction with small bowel obstruction. Prior pelvic surgery, malignancy, and radiation therapy may be associated with this presentation.

CASE

An 83-year-old multiparous woman with a history of poorly differentiated endometrial adenocarcinoma was treated with radiation therapy, total abdominal hysterectomy, and salpingo-oophorectomy. Anterior exenteration was performed for a recurrence. Seventeen years after her last pelvic operation, she had small bowel obstruction that coincided with a worsening post-hysterectomy vaginal vault prolapse. Surgical management included a side-to-side ileoileostomy and excision with closure of the vaginal apex.

CONCLUSION

Although pelvic organ prolapse primarily affects quality of life, clinicians should be alert for bowel obstruction occurring with post-hysterectomy vaginal vault prolapse.