Epigenetic Regulation of Claudin-1 in the Development of Ovarian Cancer Recurrence and Drug Resistance.

Over 21,000 women are diagnosed with ovarian cancer (OC) in the United States each year and over half that number succumb to this disease annually, often due to recurrent disease. A deeper understanding of the molecular events associated with recurrent disease is needed to identify potential targets. Using genome-scale DNA methylation and gene expression data for 16 matched primary-recurrent advanced stage serous epithelial OCs, we discovered that Claudin-1 (CLDN1), a tight junction protein, shows a stronger correlation between expression and methylation in recurrent versus primary OC at multiple CpG sites (R= -0.47 to -0.64 versus R= -0.32 to -0.57, respectively). An independent dataset showed that this correlation is stronger in tumors from short-term (<3y) survivors than in tumors from long-term (>7y) survivors (R= -0.41 to -0.46 versus R= 0.06 to -0.19, respectively). The presence of this inverse correlation in short-term survivors and recurrent tumors suggests an important role for this relationship and potential predictive value for disease prognosis. CLDN1 expression increased following pharmacologic inhibition of DNA methyltransferase activity (p< 0.001), thus validating the role of methylation in CLDN1 gene inhibition. CLDN1 knockdown enhanced chemosensitivity and suppressed cell proliferation, migration, and wound healing (p< 0.05). Stable CLDN1 knockdown in vivo resulted in reduced xenograft tumor growth but did not reach significance. Our results indicate that the relationship between CLDN1 methylation and expression plays an important role in OC aggressiveness and recurrence.

Costs, effectiveness, and workload impact of management strategies for women with an adnexal mass.

BACKGROUND: We compared the estimated clinical outcomes, costs, and physician workload resulting from available strategies for deciding which women with an adnexal mass should be referred to a gynecologic oncologist. METHODS: We used a microsimulation model to compare five referral strategies: 1) American Congress of Obstetricians and Gynecologists (ACOG) guidelines, 2) Multivariate Index Assay (MIA) algorithm, 3) Risk of Malignancy Algorithm (ROMA), 4) CA125 alone with lowered cutoff values to prioritize test sensitivity over specificity, 5) referral of all women (Refer All). Test characteristics and relative survival were obtained from the literature and data from a biomarker validation study. Medical costs were estimated using Medicare reimbursements. Travel costs were estimated using discharge data from Surveillance, Epidemiology and End Results-Medicare and State Inpatient Databases. Analyses were performed separately for pre- and postmenopausal women (60 000 "subjects" in each), repeated 10 000 times. RESULTS: Refer All was cost-effective compared with less expensive strategies in both postmenopausal (incremental cost-effectiveness ratio [ICER] $9423/year of life saved (LYS) compared with CA125) and premenopausal women (ICER $10 644/YLS compared with CA125), but would result in an additional 73 cases/year/subspecialist. MIA was more expensive and less effective than Refer All in pre- and postmenopausal women. If Refer All is not a viable option, CA125 is an optimal strategy in postmenopausal women. CONCLUSIONS: Referral of all women to a subspecialist is an efficient strategy for managing women with adnexal masses requiring surgery, assuming sufficient capacity for additional surgical volume. If a test-based triage strategy is needed, CA125 with lowered cutoff values is a cost-effective strategy.

Metastatic adenocarcinoma after laparoscopic supracervical hysterectomy with morcellation: A case report.

•Uterine morcellation is common in minimally invasive hysterectomy but should be performed with caution due to risk of unsuspected malignancy.•Intraoperative techniques should be considered to minimize dissemination of endometrial tissue during morcellation.•Strategies to ensure accurate pathologic evaluation of morcellated specimens and to improve preoperative risk stratification before morcellation procedures are necessary.

TP53 Status is Associated with Thrombospondin1 Expression In vitro.

OBJECTIVES: To elucidate the association between thrombospondin1 (THBS1) expression and TP53 status and THBS1 promoter methylation in epithelial ovarian cancer (EOC). METHODS: Epithelial ovarian cancer cell lines with known TP53 status were analyzed for THBS1 gene expression using Affymetrix U133 microarrays and promoter methylation by pyrosequencing. THBS1 mRNA expression was obtained pre- and post-exposure to radiation and hypoxia treatment in A2780 parent wild-type (wt) and mutant (m)TP53 cells. THBS1 expression was compared to tumor growth properties. RESULTS: THBS1 gene expression was higher in cells containing a wtTP53 gene or null TP53 mutation (p = 0.005) and low or absent p53 protein expression (p = 0.008) compared to those harboring a missense TP53 gene mutation and exhibiting high p53 protein expression. Following exposure to radiation, there was a 3.4-fold increase in THBS1 mRNA levels in the mTP53 versus wtTP53 A2780 cells. After exposure to hypoxia, THBS1 mRNA levels increased approximately fourfold in both wtTP53 and mTP53 A2780 cells. Promoter methylation levels were low (median = 8.6%; range = 3.5-88.8%). There was a non-significant inverse correlation between THBS1 methylation and transcript levels. There was no association between THBS1 expression and population doubling time, invasive capacity, or anchorage-independent growth. CONCLUSION: THBS1 expression may be regulated via the TP53 pathway, and induced by hypoxic tumor microenvironment conditions. Overall low levels of THBS1 promoter methylation imply that methylation is not the primary driver of THBS1 expression in EOC.

Validation of ovarian cancer gene expression signatures for survival and subtype in formalin fixed paraffin embedded tissues.

INTRODUCTION: Gene expression signatures have been identified for epithelial ovarian cancer survival (TCGA) and intrinsic subtypes (Tothill et al.). One obstacle to clinical translation is that these signatures were developed using frozen tissue, whereas usually only formalin-fixed, paraffin embedded (FFPE) tissue is available. The aim of this study was to determine if gene expression signatures can be translated to fixed archival tissues. METHODS: RNA extracted from FFPE sections from 240 primary ovarian cancers was analyzed by DASL on Illumina BeadChip arrays. Concordance of expression at the individual gene level was assessed by comparing array data from the same cancers (30 frozen samples analyzed on Affymetrix arrays versus FFPE DASL). RESULTS: The correlation between FFPE and frozen survival signature estimates was 0.774. The TCGA signature using DASL was predictive of survival in 106 advanced stage high grade serous ovarian cancers (median survival 33 versus 60 months, estimated hazard ratio for death 2.30, P=0.0007). Similar to Tothill, we found using DASL that most high grade serous ovarian cancers (102/110, 93%) were assigned to subtypes 1, 2, 4 and 5, whereas most endometrioid, clear cell, mucinous and low grade serous cases (39/57, 68%) were assigned to subtypes 3 and 6 (P<10e-15). CONCLUSIONS: Although individual probe estimates of microarrays may be weakly correlated between FFPE and frozen samples, combinations of probes have robust ability to predict survival and subtype. This suggests that it may be possible to use these signatures for prognostic and predictive purposes as we seek to individualize the treatment of ovarian cancer.

Cost comparison of strategies for the management of venous thromboembolic event risk following laparotomy for ovarian cancer.

OBJECTIVE: To evaluate the costs and effectiveness of thromboprophylaxis strategies following laparotomy for ovarian cancer. METHODS: We constructed a decision model to evaluate six strategies for management of postoperative venous thromboembolism (VTE) risk: (1) no thromboprophylaxis; (2) inpatient sequential compression device (SCD); (3) inpatient unfractionated heparin (UFH) 5000 units TID; (4) inpatient low molecular weight heparin (LMWH) 40 mg daily; (5) UFH 5000 units TID×1 month; (6) LMWH 40 mg daily×1 month. Rates of VTE, heparin-induced thrombocytopenia, and significant bleeding for each strategy were obtained from published literature. Costs were based on institutional charges or obtained from the Agency for Healthcare Research and Quality Nationwide Inpatient Sample database for 2008 and average wholesale pricing. Sensitivity analyses were performed to account for uncertainty in estimates. RESULTS: In the base case, UFH×1 month was the least expensive (mean cost $1611) and most effective (VTE risk 1.9%) strategy. LMWH×1 month was equally effective but more expensive ($2197). Inpatient UFH, inpatient LMWH, and SCDs were less effective and more expensive than UFH×1 month. In the sensitivity analysis, cost rankings remained unchanged unless the baseline probability of VTE was assumed <6.5%, the cost of VTE treatment was <$20,000, or the cost of bleeding was >$4500. LMWH×1 month became least expensive when cost was decreased 38%. CONCLUSION: Based on current evidence, extended prophylaxis with UFH is the least expensive and most effective strategy to prevent postoperative VTE following laparotomy for ovarian cancer.

A review of cost-effectiveness studies in ovarian cancer.

BACKGROUND: Ovarian cancer is the fifth leading cause of all cancer-related deaths among women. While the costs of diagnosis and treatment impact the affected individual and the health system, the most important costs for the patient are often the pain and suffering associated with ovarian cancer. The quality of life associated with any management decision should be closely examined. Cost-effectiveness models take into account costs, effects, and quality of life and provide clinicians with useful tools to aid in making these difficult decisions. METHODS: A comprehensive review of cost-effectiveness analyses was undertaken concerning screening for and treatment of ovarian cancer. RESULTS: Screening methods to detect ovarian cancer are unproven, and the majority of women present with advanced-stage disease. Multimodal screening strategies with high specificities targeted at the highest-risk individuals are the most likely strategies to be cost-effective. Primary treatment with intravenous paclitaxel and platinum regimens has proven to be cost-effective in multiple studies. Studies evaluating intraperitoneal chemotherapy show that this strategy is potentially cost-effective over a long-term time horizon. A cost-effectiveness analysis of the management of recurrent platinum-sensitive ovarian cancer showed that treatment with carboplatin and paclitaxel is cost-effective compared to single-agent therapy. However, the preferred option for patients with recurrent platinum-resistant ovarian cancer appears to be supportive care (no chemotherapy) or single-agent therapy. CONCLUSIONS: Many therapeutic choices are cost-effective in the treatment of ovarian cancer. Cost-effectiveness models offer one way to examine options in the management of a disease. The quality of life of the patient should be the most important factor in any management decision and is incorporated into well-designed studies on cost-effectiveness.

Robotic surgery in gynecologic oncology fellowship programs in the USA: a survey of fellows and fellowship directors.

BACKGROUND: In order to understand how robotic surgery impacts gynecologic oncology fellowship training and surgical practices, a survey of fellows and fellowship directors was conducted. METHODS: Questionnaires designed to determine the prevalence, application, and acceptance of robotics were sent to fellows and fellowship directors in approved U.S. programs. RESULTS: Of the respondents, 95% have a robot at their institution and 95% utilize it. Most responding fellowship directors (70%) reported that fellow education is enhanced by robotic surgery. Most fellows (65%) who responded feel comfortable using the robot, and 94% plan on performing robotic surgery upon completion of fellowship training. CONCLUSIONS: This survey demonstrates that robotic surgery is utilized in the majority of responding gynecologic oncology fellowship programs for a wide array of indications. Fellowship directors and fellows-in-training generally have a favorable view of this evolving technology. Based on these responses, robotic surgery will play an increasingly important role in the future.

Expression signatures of TP53 mutations in serous ovarian cancers.

BACKGROUND: Mutations in the TP53 gene are extremely common and occur very early in the progression of serous ovarian cancers. Gene expression patterns that relate to mutational status may provide insight into the etiology and biology of the disease. METHODS: The TP53 coding region was sequenced in 89 frozen serous ovarian cancers, 40 early stage (I/II) and 49 advanced stage (III/IV). Affymetrix U133A expression data was used to define gene expression patterns by mutation, type of mutation, and cancer stage. RESULTS: Missense or chain terminating (null) mutations in TP53 were found in 59/89 (66%) ovarian cancers. Early stage cancers had a significantly higher rate of null mutations than late stage disease (38% vs. 8%, p < 0.03). In advanced stage cases, mutations were more prevalent in short term survivors than long term survivors (81% vs. 30%, p = 0.0004). Gene expression patterns had a robust ability to predict TP53 status within training data. By using early versus late stage disease for out of sample predictions, the signature derived from early stage cancers could accurately (86%) predict mutation status of late stage cancers. CONCLUSIONS: This represents the first attempt to define a genomic signature of TP53 mutation in ovarian cancer. Patterns of gene expression characteristic of TP53 mutation could be discerned and included several genes that are known p53 targets or have been described in the context of expression signatures of TP53 mutation in breast cancer.

The risk of gastrointestinal perforation and/or fistula in patients with recurrent ovarian cancer receiving bevacizumab compared to standard chemotherapy: a retrospective cohort study.

OBJECTIVE: To determine the rate of gastrointestinal perforation and/or fistula in patients with recurrent ovarian cancer treated with and without bevacizumab. METHODS: A retrospective chart review from January 2004 to August 2007 identified two cohorts of patients with recurrent ovarian cancer: 1) patients who were receiving bevacizumab either alone or in combination with standard chemotherapy; 2) patients who were receiving standard chemotherapy alone. Gastrointestinal toxicity (perforation and fistula) was assessed using NCI Common Toxicity Criteria. Relative risk and 95% confidence intervals were calculated. Chi square test and student's t test were used for statistical analysis. RESULTS: Sixty-eight patients receiving bevacizumab for recurrent ovarian cancer were identified. 67% of these patients received chemotherapy in combination with bevacizumab. For comparison, 195 patients receiving standard chemotherapy alone for recurrent ovarian cancer were identified. A history of previous gastrointestinal resection (40% vs. 37%; p=0.79) and gastrointestinal obstruction (30% vs. 27%; p=0.74) was similar in both cohorts. Five patients (7.2%) developed a gastrointestinal perforation and/or fistula in the bevacizumab cohort compared to 13 patients (6.5%) in the chemotherapy alone cohort. The relative risk for developing a perforation and/or fistula is 1.09 (95% CI, 0.40 to 2.96). CONCLUSIONS: Although a substantial number of patients with recurrent ovarian cancer experience gastrointestinal obstruction, the rate of gastrointestinal perforation and/or fistula is relatively low. Treatment with bevacizumab does not significantly increase gastrointestinal toxicity compared to standard salvage chemotherapy.