Suha Deen

Hormone-receptor expression and ovarian cancer survival: an Ovarian Tumor Tissue Analysis consortium study

BACKGROUND Few biomarkers of ovarian cancer prognosis have been established, partly because subtype-specific associations might be obscured in studies combining all histopathological subtypes. We examined whether tumour expression of the progesterone receptor (PR) and oestrogen receptor (ER) was associated with subtype-specific survival. METHODS 12 studies participating in the Ovarian Tumor Tissue Analysis consortium contributed tissue microarray sections and clinical data to our study. Participants included in our analysis had been diagnosed with invasive serous, mucinous, endometrioid, or clear-cell carcinomas of the ovary. For a patient to be eligible, tissue microarrays, clinical follow-up data, age at diagnosis, and tumour grade and stage had to be available. Clinical data were obtained from medical records, cancer registries, death certificates, pathology reports, and review of histological slides. PR and ER statuses were assessed by central immunohistochemistry analysis done by masked pathologists. PR and ER staining was defined as negative (<1% tumour cell nuclei), weak (1 to <50%), or strong (≥50%). Associations with disease-specific survival were assessed. FINDINGS 2933 women with invasive epithelial ovarian cancer were included: 1742 with high-grade serous carcinoma, 110 with low-grade serous carcinoma, 207 with mucinous carcinoma, 484 with endometrioid carcinoma, and 390 with clear-cell carcinoma. PR expression was associated with improved disease-specific survival in endometrioid carcinoma (log-rank p<0·0001) and high-grade serous carcinoma (log-rank p=0·0006), and ER expression was associated with improved disease-specific survival in endometrioid carcinoma (log-rank p<0·0001). We recorded no significant associations for mucinous, clear-cell, or low-grade serous carcinoma. Positive hormone-receptor expression (weak or strong staining for PR or ER, or both) was associated with significantly improved disease-specific survival in endometrioid carcinoma compared with negative hormone-receptor expression, independent of study site, age, stage, and grade (hazard ratio 0·33, 95% CI 0·21-0·51; p<0·0001). Strong PR expression was independently associated with improved disease-specific survival in high-grade serous carcinoma (0·71, 0·55-0·91; p=0·0080), but weak PR expression was not (1·02, 0·89-1·18; p=0·74). INTERPRETATION PR and ER are prognostic biomarkers for endometrioid and high-grade serous ovarian cancers. Clinical trials, stratified by subtype and biomarker status, are needed to establish whether hormone-receptor status predicts response to endocrine treatment, and whether it could guide personalised treatment for ovarian cancer. FUNDING Carraresi Foundation and others.

Vascular Endothelial Growth Factor Expression in Ovarian Cancer: A Model for Targeted Use of Novel Therapies?

Purpose: Angiogenesis has a vital role in tumor growth and metastasis, and vascular endothelial growth factor (VEGF) represents a potent cytokine in this process. However, the influence of VEGF in ovarian cancer remains controversial. Interest has focused on the use of antiangiogenic drugs in ovarian cancer. This study aims to establish the pattern of expression and effect on prognosis of VEGF in a large population of ovarian cancer patients and to potentially identify a cohort in whom antiangiogenic therapy is appropriate. Experimental Design: Using a tissue microarray of 339 primary ovarian cancers, the expression of VEGF was assessed immunohistochemically. Coupled to a comprehensive database of clinicopathologic variables, its effect on these factors and survival was studied. Results: Tumors expressing high levels of VEGF had significantly poorer survival (P = 0.04). Factors shown to predict prognosis independently of each other were age, International Federation of Gynecologists and Obstetricians stage, and the absence of macroscopic disease after surgery. VEGF was independently predictive of prognosis on multivariate analysis (P = 0.02). There was no correlation between VEGF and any clinicopathologic variable. High expression of VEGF was seen in only 7% of the tumors, suggesting that the role of antiangiogenic drugs may be limited to a small subset of patients. Conclusion: High VEGF expression occurs in a small proportion of ovarian cancers, and this independently predicts poor prognosis. The small percentage of tumors with high levels of VEGF activity suggests that the role of bevacizumab may potentially be limited to a few patients; these patients could be targeted by molecular profiling.

The chemokine, CXCL12, is an independent predictor of poor survival in ovarian cancer.

Background:The chemokine CXCL12 and its cognate receptor, CXCR4, have been implicated in numerous tumour types where expression promotes tumour growth, angiogenesis, metastasis and suppresses tumour immunity.Methods:Using a tissue microarray of 289 primary ovarian cancers coupled to a comprehensive database of clinicopathological variables, the expression of CXCL12 and CXCR4 was assessed by immunohistochemistry and its impact in terms of survival and clinicopathological variables was determined.Results:Patients whose tumours expressed high levels of CXCL12 had significantly poorer survival (P=0.026) than patients whose tumours failed to produce this chemokine. Lack of CXCL12 expression within tumours was associated with a 51-month survival advantage for patients when compared with patients whose tumours expressed high levels of CXCL12. FIGO stage, adjuvant chemotherapy and the absence of macroscopic disease after surgery were all shown to predict prognosis independently of each other in this cohort of patients. CXCL12 was independently predictive of prognosis on multivariate analysis (P=0.016). There was no correlation between CXCL12 and any clinicopathological variable.Conclusion:The chemokine CXCL12 is an independent predictor of poor survival in ovarian cancer. High expression of CXCL12 was seen in only 20% of the tumours, suggesting a role for anti-CXCL12/CXCR4 therapy in the management of these patients.

Human Leukocyte Antigen Class I Antigen Expression Is an Independent Prognostic Factor in Ovarian Cancer

Purpose: Despite improvements in cancer treatment, the prognosis of ovarian cancer remains low and imperfectly predicted by traditional pathologic criteria. Biomarkers that predict prognosis independently of such criteria shed light on important molecular variations, aiding in the development and targeting of novel therapies. Previous work has shown human leukocyte antigen (HLA) class I antigen expression to be independently predictive of prognosis in colorectal and breast cancer. We investigated the prognostic potential of HLA class I antigen expression by studying a large series of ovarian cancers. Experimental Design: A tissue microarray of 339 ovarian cancer cases linked to prospectively recorded clinicopathologic and follow-up data was constructed. This was stained following a standard immunohistochemical protocol for HLA class I heavy chain (HC-10) and β2-microglobulin (β2-m). HLA class I antigen expression was compared with clinicopathologic factors and overall disease-specific survival using the Pearson χ2 test, Kaplan-Meier curves, and the log-rank test. Cox regression was used to test for the independence and magnitude of effects. Results: There were no univariate correlations between HLA class I antigen expression and clinicopathologic factors. Deviation from an HC-10+/β2-m+ phenotype correlated with reduced survival in univariate analysis (log-rank, 5.69; P = 0.017); a retained HC-10+/β2-m+ phenotype predicted improved prognosis independently of age, stage, level of cytoreduction, and chemotherapy usage on multivariate analysis (hazard ratio, 0.587; 95% confidence interval, 0.442-0.781; P < 0.001). Conclusions: HLA class I antigen expression is an independent prognostic marker in ovarian cancer, its loss correlating with a poor prognostic outcome.

Combined image and genomic analysis of high-grade serous ovarian cancer reveals PTEN loss as a common driver event and prognostic classifier.

BackgroundTP53 and BRCA1/2 mutations are the main drivers in high-grade serous ovarian carcinoma (HGSOC). We hypothesise that combining tissue phenotypes from image analysis of tumour sections with genomic profiles could reveal other significant driver events.ResultsAutomatic estimates of stromal content combined with genomic analysis of TCGA HGSOC tumours show that stroma strongly biases estimates of PTEN expression. Tumour-specific PTEN expression was tested in two independent cohorts using tissue microarrays containing 521 cases of HGSOC. PTEN loss or downregulation occurred in 77% of the first cohort by immunofluorescence and 52% of the validation group by immunohistochemistry, and is associated with worse survival in a multivariate Cox-regression model adjusted for study site, age, stage and grade. Reanalysis of TCGA data shows that hemizygous loss of PTEN is common (36%) and expression of PTEN and expression of androgen receptor are positively associated. Low androgen receptor expression was associated with reduced survival in data from TCGA and immunohistochemical analysis of the first cohort.ConclusionPTEN loss is a common event in HGSOC and defines a subgroup with significantly worse prognosis, suggesting the rational use of drugs to target PI3K and androgen receptor pathways for HGSOC. This work shows that integrative approaches combining tissue phenotypes from images with genomic analysis can resolve confounding effects of tissue heterogeneity and should be used to identify new drivers in other cancers.

Preventing endometrial cancer risk in polycystic ovarian syndrome (PCOS) women: Could metformin help?

Current data indicate that there is a significant risk of endometrial cancer (EC) in women with polycystic ovarian syndrome (PCOS), although further research needed to clarify the exact molecular mechanisms. Endometrial hyperplasia is a premalignant condition that usually heralds EC and it shares identical risk factors with EC. Metabolic syndrome with a triad of obesity, hyperinsulinaemia and diabetes, which is commonly observed in PCOS appears to be a key mechanism in EC pathogenesis. Measures to improve insulin resistance could therefore play a role in reducing the risk of EC in women with PCOS. Metformin is an insulin sensitising agent which is safe, widely available and currently licensed for type-2 diabetes. It has been clearly shown in both animal and human studies that metformin is of value in reversing endometrial hyperplasia. Metformin may therefore prevent EC in PCOS. This article reviews the use of metformin in reducing EC risk in PCOS and makes a case for future research on this topic.

The cadherin switch in ovarian high-grade serous carcinoma is associated with disease progression

Ovarian high-grade serous carcinoma (HGSC) often has a poor prognosis because of late presentation, lack of sensitivity and specificity of screening modalities and the development of chemoresistance. New targeted therapy is required if survival in these cases is to improve. The profile of E-, P- and N-cadherins in ovarian cancer and its association with survival remain poorly understood. Reduced expression of E-cadherin in prostate cancer associated with increase in the expression of N- and P-cadherins is described as cadherin switch. We hypothesised that there is a switch in the expression of cadherins that regulates the behaviour of HGSC and possibly its outcome. To identify the stages of the cadherin switch in HGSC, we studied the immunoexpression of E-, P- and N-cadherins in a cohort of 177 cases of HGSC. High expression of P-cadherin was associated with poor patient survival and was significantly higher in stage 2 disease when compared with stage 1 and stage 3 disease (P = 0.033). In contrast, loss of E-cadherin was observed in stage 3 HGSC when compared with other stages (P = 0.050). E-, P- and N- cadherin expressions were significantly associated with disease outcome when assessed individually and in various combinations with an interesting profile. Our results indicate that the cadherin switch alters through progression of HGSC. The profile of combined cadherin expressions in association with survival raises expectations in targeted therapy.

Loss of IFNγ Receptor Is an Independent Prognostic Factor in Ovarian Cancer

Purpose: There is evidence that IFNγ plays an important role in ovarian cancer development. IFNγ produces numerous antitumor effects and it may be evasion of these effects which allows tumor progression. We postulate that genetic instability in tumor cells may lead to modulation of expression of the IFNγ receptor, thus leading to altered tumor biology and patient prognosis. This hypothesis would support the theory of immunoediting in ovarian cancer. Experimental Design: Using tissue microarray technology of 339 primary ovarian cancers, the expression of IFNγ receptor was assessed immunohistochemically. Coupled to a comprehensive database of clinicopathologic variables, its effect on these factors was studied. Results: Tumors expressing high levels of IFNγ receptor had significantly improved survival (P = 0.017) compared with tumors expressing low levels of the receptor; this was also seen with complete receptor loss (P = 0.014). Factors shown to predict prognosis independently of each other were the following: age, International Federation of Gynecologists and Obstetricians stage, and the absence of macroscopic disease after surgery. The level of IFNγ receptor expression and complete receptor loss were independently predictive of prognosis on multivariate analysis. There was no correlation between receptor status and any of the standard clinicopathologic variables. Conclusions: Loss of IFNγ receptor independently predicts poor prognosis in ovarian cancer. Loss of receptor expression may be responsible for the limited success in the therapeutic use of IFNγ in ovarian cancer trials and highlights a subgroup of high expressing IFNγ receptor tumors which are more likely to be susceptible to such treatments.

Redox protein expression predicts progression-free and overall survival in ovarian cancer patients treated with platinum-based chemotherapy

Ovarian cancer is primarily treated with platinum-based chemotherapy, with ROS generation implicated in cytotoxicity. We examined redox protein expression in ovarian tumors, focusing on the thioredoxin system, to determine the role it might play in mediating response to therapy. Nuclear and cytoplasmic expression of thioredoxin, thioredoxin reductase, thioredoxin-interacting protein, metallothionein, and glutathione S-transferase Pi was assessed, using standard immunohistochemical techniques, on a tissue microarray of 154 primary ovarian carcinomas obtained from patients subsequently treated with adjuvant platinum-based chemotherapy. Low cytoplasmic expression of thioredoxin (p=0.032) and negative nuclear expression of metallothionein (p=0.04) significantly correlated with better progression-free survival. When nuclear and cytoplasmic expression patterns were combined those patients with tumors with low cytoplasmic but high nuclear expression of thioredoxin exhibited better progression-free (p=0.003) and overall survival (p=0.004). This combination was, using multivariate analysis, an independent predictive factor for overall survival (p=0.034). Improved progression-free survival was also seen with negative expression of metallothionein, cytoplasmic and nuclear (p=0.038), and was independent of other clinical parameters (p=0.048). Such results support the suitability of using redox protein expression to predict response and, potentially, to alter treatment options accordingly.

Evidence for a time-dependent association between FOLR1 expression and survival from ovarian carcinoma: implications for clinical testing. An Ovarian Tumour Tissue Analysis consortium study

Background:Folate receptor 1 (FOLR1) is expressed in the majority of ovarian carcinomas (OvCa), making it an attractive target for therapy. However, clinical trials testing anti-FOLR1 therapies in OvCa show mixed results and require better understanding of the prognostic relevance of FOLR1 expression. We conducted a large study evaluating FOLR1 expression with survival in different histological types of OvCa.Methods:Tissue microarrays composed of tumour samples from 2801 patients in the Ovarian Tumour Tissue Analysis (OTTA) consortium were assessed for FOLR1 expression by centralised immunohistochemistry. We estimated associations for overall (OS) and progression-free (PFS) survival using adjusted Cox regression models. High-grade serous ovarian carcinomas (HGSC) from The Cancer Genome Atlas (TCGA) were evaluated independently for association between FOLR1 mRNA upregulation and survival.Results:FOLR1 expression ranged from 76% in HGSC to 11% in mucinous carcinomas in OTTA. For HGSC, the association between FOLR1 expression and OS changed significantly during the years following diagnosis in OTTA (Pinteraction=0.01, N=1422) and TCGA (Pinteraction=0.01, N=485). In OTTA, particularly for FIGO stage I/II tumours, patients with FOLR1-positive HGSC showed increased OS during the first 2 years only (hazard ratio=0.44, 95% confidence interval=0.20–0.96) and patients with FOLR1-positive clear cell carcinomas (CCC) showed decreased PFS independent of follow-up time (HR=1.89, 95% CI=1.10–3.25, N=259). In TCGA, FOLR1 mRNA upregulation in HGSC was also associated with increased OS during the first 2 years following diagnosis irrespective of tumour stage (HR: 0.48, 95% CI: 0.25–0.94).Conclusions:FOLR1-positive HGSC tumours were associated with an increased OS in the first 2 years following diagnosis. Patients with FOLR1-negative, poor prognosis HGSC would be unlikely to benefit from anti-FOLR1 therapies. In contrast, a decreased PFS interval was observed for FOLR1-positive CCC. The clinical efficacy of FOLR1-targeted interventions should therefore be evaluated according to histology, stage and time following diagnosis.