HER2 status in ovarian carcinomas: a multicenter GINECO study of 320 patients

Aberrant expression of WWOX protein in epithelial ovarian cancer: a clinicopathologic and immunohistochemical study

Epithelial ovarian cancer is the most frequent cause of death from gynecologic cancer. The WW domain-containing oxidoreductase (WWOX) gene is located at 16q23.3-24.1, a region that spans the second most common human fragile site, FRA16D. Abnormalities affecting WWOX at the genomic and/or expression level(s) have been reported in numerous neoplasias and cancer-derived cell lines. The goal of the study was to evaluate WWOX protein expression in epithelial ovarian carcinoma tissues to determine whether they correlated with clincopathologic parameters. We performed WWOX expression analyses by means of immunohistochemistry on 112 epithelial ovarian carcinoma tissues, and ovarian carcinoma-derived SKOV3, 3AO cells. The basic significant level was fixed at P<0.05. Loss of WWOX expression was observed in 32 (28.6%) of 112 ovarian carcinoma samples and was positively correlated with negative estrogen receptor (ER) (P<0.001) and negative progesterone receptor (PR) (P=0.001). A statistically significant correlation was observed between the lack of WWOX expression and the advanced International Federation of Gynecology and Obstetrics (FIGO) stages (P=0.02). Furthermore, negative WWOX staining was significantly correlated with lymph node metastasis (P=0.013), whereas no significant differences were found between WWOX and HER-2/neu staining (P=0.79). WWOX protein expression was moderately detectable in SKOV3 cells but not in 3AO cells. Our results indicate that loss of WWOX expression in epithelial ovarian carcinomas correlates with negative ER, negative PR, advanced FIGO stages, and lymph node metastases.

Prognostic impact of prechemotherapy serum levels of HER2, CA125, and HE4 in ovarian cancer patients

OBJECTIVE

Human epididymis protein 4 (HE4) has attracted a lot of interest as a relatively novel biomarker for ovarian carcinoma. Research focus has been directed at HE4 as a diagnostic tool with potential for better triage of women with adnexal masses but the prognostic aspect of HE4 in ovarian cancer patients remains to be elucidated. The aim of the present study was to investigate the prognostic value of prechemotherapy serum HER2, cancer antigen 125 (CA125), and HE4 levels in ovarian cancer patients receiving standard combination chemotherapy.

METHODS

Serum from 139 patients with newly diagnosed ovarian cancer was analyzed for HER2, CA125, and HE4 using enzyme-linked immunosorbent assay assays. Samples were collected just before first-line chemotherapy, and all patients were treated with carboplatin-paclitaxel combination chemotherapy.

RESULTS

Increasing levels of serum HE4 (grouped into quartiles) was significantly associated with worse progression-free survival (PFS) (P < 10) and overall survival (P < 10). After adjustment in the Cox model, HE4 serum levels remained an independent prognostic parameter for PFS, with a hazard ratio of 1.77 (95% confidence interval, 1.03-3.04; P = 0.040) for patients with HE4 levels above the median compared with patients with HE4 levels below the median. The shorter PFS for patients with high levels of HE4 also translated into an independent significant difference in overall survival (hazard ratio, 3.17 [95% confidence interval, 1.41-7.10]; P = 0.005).Serum HER2 and CA125 levels did not demonstrate an independent prognostic value.

CONCLUSIONS

High levels of serum HE4 is a strong and independent indicator of worse prognosis in epithelial ovarian cancer patients.

Human epidermal growth factor receptor 2 overexpression in breast cancer of patients with anti-Yo--associated paraneoplastic cerebellar degeneration

Isolated case reports suggest that breast tumors from patients with paraneoplastic cerebellar degeneration (PCD) and Yo antibodies overexpress human epidermal growth factor receptor 2 (HER2). HER2 overexpression is present in 15%-25% of breast cancers and is associated with poor prognosis. We retrospectively analyzed the status of HER2 in breast tumors of 27 patients with anti-Yo-associated PCD to evaluate whether HER2 overexpression in this group of patients is higher than expected. In addition, we analyzed HER2 status of 19 breast tumors from patients with paraneoplastic neurological syndromes and Ri antibodies to see whether HER2 was specifically related to anti-Yo-associated PCD. We also assessed cdr2 expression (the onconeural antigen recognized by Yo antibodies) in 21 HER2-positive breast tumors from patients without paraneoplastic neurological syndromes. HER2 was overexpressed in 26 patients (96.3%) with anti-Yo-associated PCD but only in 2 patients (10.5%) with paraneoplastic neurological syndromes associated with Ri antibodies (P< .0001). Only 5 (23.8%) of the 21 HER2-positive breast tumors showed cdr2 immunoreactivity. This study shows a very high frequency of HER2 overexpression in breast cancers in patients with anti-Yo-associated PCD but not in those from patients with Ri antibodies. Although the expression of cdr2 onconeural antigen is not high in HER2-positive breast cancers, HER2 overexpression seems to be an important requirement to develop an anti-Yo-associated PCD.

Ovarian cancer: opportunity for targeted therapy

Ovarian cancer is a common cause of cancer mortality in women with limited treatment effectiveness in advanced stages. The limitation to treatment is largely the result of high rates of cancer recurrence despite chemotherapy and eventual resistance to existing chemotherapeutic agents. The objective of this paper is to review current concepts of ovarian carcinogenesis. We will review existing hypotheses of tumor origin from ovarian epithelial cells, Fallopian tube, and endometrium. We will also review the molecular pathogenesis of ovarian cancer which results in two specific pathways of carcinogenesis: (1) type I low-grade tumor and (2) type II high-grade tumor. Improved understanding of the molecular basis of ovarian carcinogenesis has opened new opportunities for targeted therapy. This paper will also review these potential therapeutic targets and will explore new agents that are currently being investigated.

The human epidermal growth factor receptor 2 (HER2)

The declared "war on cancer" aimed to eradicate this disease using our knowledge of cancer cell biology to develop novel therapeutics. One such target of these novel therapies has been the human epidermal growth factor receptor 2 (HER2) gene. Unique in the approach to abolishing function of this gene coded receptor, it was the first target of new monoclonal antibody therapy targeting the extracellular receptor and now also a target of small molecule drugs against the intracellular tyrosine kinase domain. In this instance, it was also one of the first applications of personalized medicine requiring companion diagnostics. In this manuscript, we review the biology and clinical applications of HER2 as a biomarker of disease and as a therapeutic target.

Dual-colour HER2/chromosome 17 chromogenic in situ hybridisation enables accurate assessment of HER2 genomic status in ovarian tumours

BACKGROUND

Ovarian cancer is a leading cause of gynaecological cancer-related morbidity and mortality. There has been increasing interest in the potential utility of anti-human epidermal growth factor receptor 2 (anti-HER2) agents in the treatment of this disease, with the attendant need to identify suitable predictive biomarkers of response to treatment.

AIMS/METHODS

The authors studied the prevalence of HER2 genomic amplification and overexpression in 85 ovarian tumours in the local patient cohort of this study, as well as the concordance rate between immunohistochemistry, fluorescent in situ hybridisation (FISH) and a dual-colour HER2/chromosome 17 centromere chromogenic in situ hybridisation (CISH) assay.

RESULTS

The authors identified HER2 genomic amplification and protein overexpression in 35.3% (6/17) and 29.4% (5/17), respectively, of primary ovarian mucinous carcinomas. No other cancer subtypes displayed HER2 amplification or protein overexpression. The authors also found a perfect concordance between FISH and dual-colour CISH analysis (κ coefficient 1.0, p<0.001).

CONCLUSION

The results of this study support existing reports that HER2 genomic amplification and protein overexpression are predominantly found in primary ovarian mucinous carcinomas. Given the perfect concordance between the FISH and dual-colour CISH assays and the advantages of CISH over FISH analysis, future clinical trials investigating the use of anti-HER2 therapeutics in ovarian carcinomas should incorporate dual-colour CISH as part of the HER2 status assessment algorithm.

Immunity and immune suppression in human ovarian cancer

Clinical outcomes in ovarian cancer are heterogeneous, independent of common features such as stage, response to therapy and grade. This disparity in outcomes warrants further exploration into tumor and host characteristics. One compelling issue is the response of the patient's immune system to her ovarian cancer. Several studies have confirmed a prominent role for the immune system in modifying disease course. This has led to the identification and evaluation of novel immune-modulating therapeutic approaches such as vaccination and antibody therapy. Antitumor immunity, however, is often negated by immune suppression mechanisms present in the tumor microenvironment. Thus, in the future, research into immunotherapy targeting ovarian cancer will probably become increasingly focused on combination approaches that simultaneously augment immunity while preventing local immune suppression. In this article, we summarize important immunological issues that could influence ovarian cancer outcome, including tumor antigens, endogenous immune responses, immune escape and new and developing immunotherapeutic strategies.

CXCL12 expression by healthy and malignant ovarian epithelial cells

Background

CXCL12 has been widely reported to play a biologically relevant role in tumor growth and spread. In epithelial ovarian cancer (EOC), CXCL12 enhances tumor angiogenesis and contributes to the immunosuppressive network. However, its prognostic significance remains unclear. We thus compared CXCL12 status in healthy and malignant ovaries, to assess its prognostic value.

Methods

Immunohistochemistry was used to analyze CXCL12 expression in the reproductive tracts, including the ovaries and fallopian tubes, of healthy women, in benign and borderline epithelial tumors, and in a series of 183 tumor specimens from patients with advanced primary EOC enrolled in a multicenter prospective clinical trial of paclitaxel/carboplatin/gemcitabine-based chemotherapy (GINECO study). Univariate COX model analysis was performed to assess the prognostic value of clinical and biological variables. Kaplan-Meier methods were used to generate progression-free and overall survival curves.

Results

Epithelial cells from the surface of the ovary and the fallopian tubes stained positive for CXCL12, whereas the follicles within the ovary did not. Epithelial cells in benign, borderline and malignant tumors also expressed CXCL12. In EOC specimens, CXCL12 immunoreactivity was observed mostly in epithelial tumor cells. The intensity of the signal obtained ranged from strong in 86 cases (47%) to absent in 18 cases (<10%). This uneven distribution of CXCL12 did not reflect the morphological heterogeneity of EOC. CXCL12 expression levels were not correlated with any of the clinical parameters currently used to determine EOC prognosis or with HER2 status. They also had no impact on progression-free or overall survival.

Conclusion

Our findings highlight the previously unappreciated constitutive expression of CXCL12 on healthy epithelia of the ovary surface and fallopian tubes, indicating that EOC may originate from either of these epithelia. We reveal that CXCL12 production by malignant epithelial cells precedes tumorigenesis and we confirm in a large cohort of patients with advanced EOC that CXCL12 expression level in EOC is not a valuable prognostic factor in itself.

Trial Registration

ClinicalTrials.gov: NCT00052468

Targeted agents in ovarian cancer

Despite recent advances in the treatment of ovarian cancer, a large majority of women with this diagnosis will die from recurrence of their disease. Targeted therapies, in the form of monoclonal antibodies and small molecule tyrosine kinase inhibitors have significantly altered the management of many solid tumors and hematologic malignancies. No such agents have been approved by the US FDA for use in ovarian cancer, although Phase II data suggests excellent single-agent activity of some of these drugs. Antiangiogenic agents in combination with chemotherapy are being evaluated in Phase III clinical trials, both in the adjuvant setting and in recurrent platinum-sensitive disease. Poly-ADP-ribose polymerase inhibitors are promising agents in BRCA1/2-mutated breast and ovarian cancers. Ongoing clinical trials are exploring the anti-tumor effect of poly-ADP-ribose polymerase inhibitors administered as single agents and in combination with chemotherapy. Many other new drugs are in earlier grades of development. In this article, we review the state of the art in targeted therapies for ovarian cancer and identify future directions for their development in the management of this often devastating disease.

The HER2 gene copies per tumor cell either before or after correction for chromosome-17 correlated significantly with HER2 IHC results in epithelial ovarian cancer in a tissue microarray study

BACKGROUND

HER2 gene amplification and HER2 protein overexpression are important factors in predicting clinical sensitivity to anti-HER2 monoclonal antibody therapy in breast cancer patients. The purpose of this study is to evaluate the correlation between HER2 protein expressions and the HER2 gene copies per tumor cell either before or after chromosome-17 correction in epithelial ovarian cancer (EOC).

METHODS

Adopting 2007 ASCO/CAP guideline recommendations for HER2 testing, 27 tissue microarray (TMA) samples from EOC patients were analyzed by immunohistochemistry (IHC) using Dako, c-erb-B2 antibody and subsequently examined by fluorescence in situ hybridization (FISH) using Abbott/Vysis, PathVysion HER2 DNA Probe Kit.

RESULTS

The overall concordance revealed 81.5% between HER2 IHC and HER2 FISH results. Additionally, HER2 gene copies prior to chromosome-17 correction increased significantly in a stepwise order through the negative, equivocal, and positive IHC result categories (P = 0.026), as did the HER2 gene copies after chromosome-17 correction (P = 0.028). On the other hand, HER2 IHC results correlated significantly with both chromosome-17 uncorrected HER2 gene copy numbers (ρ = 0.430, P = 0.025) and chromosome-17 corrected HER2 gene copy numbers (ρ = 0.524, P = 0.027).

CONCLUSION

We demonstrated that both chromosome-17 corrected and uncorrected HER2 gene copies correlated significantly with HER2 IHC result categories; and tests for the HER2 gene copies per tumor cell either before or after correction for chromosome-17 can be applied as a potentially valuable tool in analyzing the HER2 status in EOC.

Prognostic significance of HER2 expression in neuroblastic tumors

HER2 is essential for normal embryonic development and has a critical function in oncogenesis and progression of some types of cancer. Neuroblastic tumors create a heterogenous group of pediatric embryonal tumors of sympathoadrenal lineage. The biological and prognostic function of HER2 in these tumors is not well established. In this study, we evaluated the status of HER2, its prognostic significance, and clinicopathological correlations in series of 79 untreated neuroblastoma. The immunohistochemical assessment of HER2 and Ki-67 (proliferation index) as well as HER2 copy number status were performed on tissue microarrays. HER2 expression characterized 63 tumors, including 34 with low and 29 with high level, showing either membranous or mixed membranous-cytoplasmic pattern. Sixteen cases were HER2 immunonegative. The pattern of immunolabeling depended on the maturity of neuroblastic cells, being the most intense in differentiating neuroblasts. None of the tumors revealed HER2 amplification. In the examined group, 20% of patients died of disease from 4 to 107 months (median 18) from the diagnosis, and the survivors were followed up for 14-149 months (median 59). Patients' age, stage of disease, tumor location, mitosis/karyorrhexis index (MKI), and presence of HER2 expression were statistically significantly related to survival probability as detected by the Cox proportional hazard model. In the univariate analysis, Kaplan-Meier curves revealed significantly poorer outcome of HER2 negative than HER2-positive tumors (either low or high expression). The immunonegativity was associated with adverse clinicopathological parameters, including poor survival, metastatic stage of disease, un- or poorly differentiated histology, high MKI, and higher proliferation index. In conclusion, HER2 expression, not accompanied by gene amplification, is common in neuroblastic tumors. HER2 positivity seems to have a positive prognostic significance. HER2 expression with a variable pattern is a marker of the stage of neuroblastic cells differentiation.

Predictive and prognostic protein biomarkers in epithelial ovarian cancer: recommendation for future studies

Epithelial ovarian cancer is the most lethal gynecological malignancy. Due to its lack of symptoms, this disease is diagnosed at an advanced stage when the cancer has already spread to secondary sites. While initial rates of response to first treatment is >80%, the overall survival rate of patients is extremely low, mainly due to development of drug resistance. To date, there are no reliable clinical factors that can properly stratify patients for suitable chemotherapy strategies. Clinical parameters such as disease stage, tumor grade and residual disease, although helpful in the management of patients after their initial surgery to establish the first line of treatment, are not efficient enough. Accordingly, reliable markers that are independent and complementary to clinical parameters are needed for a better management of these patients. For several years, efforts to identify prognostic factors have focused on molecular markers, with a large number having been investigated. This review aims to present a summary of the recent advances in the identification of molecular biomarkers in ovarian cancer patient tissues, as well as an overview of the need and importance of molecular markers for personalized medicine in ovarian cancer.

Trastuzumab Sensitizes Ovarian Cancer Cells to EGFR-targeted Therapeutics

Background

Early studies have demonstrated comparable levels of HER2/ErbB2 expression in both breast and ovarian cancer. Trastuzumab (Herceptin), a therapeutic monoclonal antibody directed against HER2, is FDA-approved for the treatment of both early and late stage breast cancer. However, clinical studies of trastuzumab in epithelial ovarian cancer (EOC) patients have not met the same level of success. Surprisingly, however, no reports have examined either the basis for primary trastuzumab resistance in ovarian cancer or potential ways of salvaging trastuzumab as a potential ovarian cancer therapeutic.

Methods

An in vitro model of primary trastuzumab-resistant ovarian cancer was created by long-term culture of HER2-positive ovarian carcinoma-derived cell lines with trastuzumab. Trastuzumab treated vs. untreated parental cells were compared for HER receptor expression, trastuzumab sensitivity, and sensitivity to other HER-targeted therapeutics.

Results

In contrast to widely held assumptions, here we show that ovarian cancer cells that are not growth inhibited by trastuzumab are still responsive to trastuzumab. Specifically, we show that responsiveness to alternative HER-targeted inhibitors, such as gefitinib and cetuximab, is dramatically potentiated by long-term trastuzumab treatment of ovarian cancer cells. HER2-positive ovarian carcinoma-derived cells are, therefore, not "unresponsive" to trastuzumab as previously assumed, even when they not growth inhibited by this drug.

Conclusions

Given the recent success of EGFR-targeted therapeutics for the treatment of other solid tumors, and the well-established safety profile of trastuzumab, results presented here provide a rationale for re-evaluation of trastuzumab as an experimental ovarian cancer therapeutic, either in concert with, or perhaps as a "primer" for EGFR-targeted therapeutics.

Inhibition of functional HER family members increases the sensitivity to docetaxel in human ovarian cancer cell lines

Human epidermal growth factor (HER) family-targeted therapy combined with standard cytotoxic agents might improve the treatment of ovarian cancer. Human ovarian cancer cell lines OVCAR-3, IGROV-1, and SKOV-3 with differential EGFR, HER2, and HER3 expression levels were used to study whether EGFR-directed (cetuximab) or HER2-directed (trastuzumab, pertuzumab) monoclonal antibodies inhibited cell growth and abrogated activated receptor signaling routes. Possible increase of antiproliferative effects and further activation of caspase-3 as a read-out for apoptosis were analyzed when monoclonal antibodies were combined with docetaxel. Cetuximab alone inhibited cell growth in OVCAR-3 and IGROV-1, which was more pronounced when combined with pertuzumab in OVCAR-3. SKOV-3 cell growth was not significantly affected by any of the antibodies. Cetuximab increased the 50% growth-inhibiting effects of docetaxel in OVCAR-3 and IGROV-1, but not in SKOV-3. Coaddition of pertuzumab to cetuximab plus docetaxel in OVCAR-3 and IGROV-1, and, to a lesser extent trastuzumab in OVCAR-3, inhibited cell growth even further. Caspase-3 activation by docetaxel was enhanced after addition of cetuximab in OVCAR-3 and after addition of cetuximab plus pertuzumab in IGROV-1 and SKOV-3. Functional EGFR-signaling, HER2-signaling, and HER3-signaling routes as shown from abrogation of EGF-stimulated and heregulin-stimulated phosphorylated ERK1/2 by cetuximab, trastuzumab, and pertuzumab, respectively, were shown in OVCAR-3 and IGROV-1, but hardly in SKOV-3. Pertuzumab was able to abrogate phosphorylated HER2 by EGF and heregulin, except in SKOV-3. In conclusion, a combination of docetaxel with inhibitors of HER family members, such as cetuximab plus pertuzumab, may be considered for a clinical trial in ovarian carcinomas with functional receptors.

Serous papillary peritoneal carcinoma: unknown primary tumour, ovarian cancer counterpart or a distinct entity? A systematic review

INTRODUCTION

Serous peritoneal papillary carcinoma (SPPC), though managed according to ovarian cancer therapeutic principles, has been variably considered as an ovarian cancer counterpart, a peritoneal malignancy with distinct characteristics or a cancer of unknown primary (CUP).

PATIENTS AND METHODS

We systematically reviewed all publications studying molecular pathophysiology, clinical presentation, management and outcome of at least 10 patients with SPPC from 1980 to 2008 in anglophone medical journals and critically analysed the data.

RESULTS

Molecular profiling of CUP was performed in eight papers reporting on 211 patients with stage III/IV SPPC by means of immunohistochemistry or PCR-based assays. Twenty-five clinical series, mostly retrospective, reported management and outcome of 579 patients with SPPC, in several cases matched to advanced ovarian cancer controls. Though we did not identify statistically significant differences in molecular biology, clinical presentation, management and outcome of SPPC and ovarian cancer cases, some subtle differences emerged: patterns of loss of heterozygosity at several chromosomal loci differed from those seen in ovarian cancer, while the overexpression of the HER2 oncogene was encountered more often. Serous peritoneal tumours affected older patients and were more frequently multifocal or exhibited virulent clonal expansion in metastatic sites. Diffuse micronodular spread formed a high total load of malignancy in omental, peritoneal surfaces, difficult to debulk optimally. Despite effective chemotherapeutic cytoreduction and occasional long-term remissions, SPPC patients survived 2-6 months less than ovarian cancer patients.

CONCLUSIONS

Patients with SPPC should not be classified in the poor-risk CUP category, in view of the therapeutic and prognostic differences. Still, the assimilation of the SPPC entity by ovarian cancer hindered further research into its genotypic and phenotypic characteristics that may differ from ovarian cancer. Subgroup analyses of large ovarian cancer trials may shed light in this issue.

Assessing HER2 gene amplification as a potential target for therapy in invasive urothelial bladder cancer with a standardized methodology: results in 1005 patients

Background: This study assessed the human epidermal growth factor receptor-2 (HER2) protein expression and its relationship with gene amplification in invasive bladder carcinoma, using the same criteria than for breast cancer.

Patients and methods: In 1005 patients, paraffin-embedded tissues of transurethral resection or cystectomy were evaluated by immunohistochemistry (IHC), using antibodies against HER2. All samples with a 2+ or 3+ HER2 overexpression were evaluated by FISH.

Results: HER2 overexpression was observed in 93 (9.2%) tumors (2+: 42 tumors and 3+: 51 tumors). Using FISH, all HER2 3+ tumors had a gene amplification, whereas no amplification was found in 2+ tumors. Intratumoral heterogeneity was observed in 35% of cases. These tumors showed the same heterogeneous pattern, with adjacent 3+ positive and negative areas by both IHC and FISH.

Conclusions: This study showed that 5.1% of invasive bladder carcinomas had a HER2 gene amplification. These findings may have clinical implications for the management of patients with HER2-positive locally advanced or metastatic bladder cancer, as they could be potential candidates for targeted therapy.

Immunoselection of breast and ovarian cancer cells with trastuzumab and natural killer cells: selective escape of CD44high/CD24low/HER2low breast cancer stem cells

Although trastuzumab (Herceptin) has substantially improved the overall survival of patients with mammary carcinomas, even initially well-responding tumors often become resistant. Because natural killer (NK) cell-mediated antibody-dependent cell-mediated cytotoxicity (ADCC) is thought to contribute to the therapeutic effects of trastuzumab, we have established a cell culture system to select for ADCC-resistant SK-OV-3 ovarian cancer and MCF7 mammary carcinoma cells. Ovarian cancer cells down-regulated HER2 expression, resulting in a more resistant phenotype. MCF7 breast cancer cells, however, failed to develop resistance in vitro. Instead, treatment with trastuzumab and polyclonal NK cells resulted in the preferential survival of individual sphere-forming cells that displayed a CD44(high)CD24(low) "cancer stem cell-like" phenotype and expressed significantly less HER2 compared with non-stem cells. Likewise, the CD44(high)CD24(low) population was also found to be more immunoresistant in SK-BR3, MDA-MB231, and BT474 breast cancer cell lines. When immunoselected MCF7 cells were then re-expanded, they mostly lost the observed phenotype to regenerate a tumor cell culture that displayed the initial HER2 surface expression and ADCC-susceptibility, but was enriched in CD44(high)CD24(low) cancer stem cells. This translated into increased clonogenicity in vitro and tumorigenicity in vivo. Thus, we provide evidence that the induction of ADCC by trastuzumab and NK cells may spare the actual tumor-initiating cells, which could explain clinical relapse and progress. Moreover, our observation that the "relapsed" in vitro cultures show practically identical HER2 surface expression and susceptibility toward ADCC suggests that the administration of trastuzumab beyond relapse might be considered, especially when combined with an immune-stimulatory treatment that targets the escape variants.

Modulation of HER3 is a marker of dynamic cell signaling in ovarian cancer: implications for pertuzumab sensitivity

This study was designed to evaluate the expression of HER receptors as a marker of sensitivity to the humanized anti-HER2 monoclonal antibody pertuzumab in ovarian cancer cells. In a recent clinical trial, low levels of HER3 mRNA have been shown to associate with pertuzumab response when combined with gemcitabine. We sought to define how pertuzumab modulated HER expression levels in ovarian cancer using cell line models to better understand differential and dynamic receptor expression in therapeutic response. Changes in HER3 mRNA expression were also assessed in pertuzumab-treated xenografts. HER3 mRNA and, to a lesser extent, HER2, were down-regulated after stimulation both with heregulin-beta1 and epidermal growth factor in a range of ovarian cancer cell lines either growth sensitive or growth resistant to pertuzumab. Pertuzumab reversed this down-regulation and the magnitude of the reversal correlated with pertuzumab sensitivity. The change in HER3 mRNA expression correlated inversely to how much the extracellular signal-regulated kinase and phosphoinositide 3-kinase pathways were dynamically activated with stimulation. Finally, up-regulation of HER3 mRNA was found in cancer xenografts treated with pertuzumab. We conclude that HER3 mRNA is down-regulated by both heregulin-beta1 and epidermal growth factor activation. This suggests that in some tumors, low HER3 mRNA expression is driven by, or dependent on, growth factor. HER3 mRNA expression is effectively reversed in pertuzumab-sensitive tumors. These data are consistent with low HER3 mRNA identifying a pertuzumab-sensitive phenotype.

Chemosensitivity and chemoresistance testing in ovarian cancer

PURPOSE OF REVIEW

Sensitivity testing in ovarian cancer to individualize therapy remains an active area of interest and this has been renewed recently by results from several groups. The clinical results of assay-directed therapy are invariably better than would be expected from empirical treatment, but it has proved difficult to get these tests into practice.

RECENT FINDINGS

Several recent studies suggest that cellular individualized tumour response tests, particularly the ATP-based tumour chemosensitivity assay, can improve the chance of response and probably survival for individual patients. Most tumour response tests show excellent correlation with clinical resistance, but vary in their ability to predict sensitivity. Molecular assays of sensitivity and resistance are less developed in ovarian cancer than in breast cancer, but those using multiple gene signatures show considerable promise.

SUMMARY

Individualized therapy has the ability to guide the use of chemotherapy as well as newer agents. The development of companion diagnostics for drugs used in ovarian cancer has considerable potential for the future and such assays are already proving useful where there is clinical evidence of equivalence between possible treatments.

Modest effect of p53, EGFR and HER-2/neu on prognosis in epithelial ovarian cancer: a meta-analysis

BACKGROUND

P53, EGFR and HER-2/neu are the most frequently studied molecular biological parameters in epithelial ovarian cancer, but their prognostic impact is still unequivocal. We performed a meta-analysis to more precisely estimate their prognostic significance.

METHODS

Published studies that investigated the association between p53, EGFR and HER-2/neu status and survival were identified. Meta-analysis was performed using a DerSimonian-Laird model. Publication bias was investigated using funnel plots and sources of heterogeneity were identified using meta-regression analysis.

RESULTS

A total of 62 studies were included for p53, 15 for EGFR and 20 for HER-2/neu. P53, EGFR and HER-2/neu status had a modest effect on overall survival (pooled HR 1.47, 95% CI 1.33-1.61 for p53; HR 1.65, 95% CI 1.25-2.19 for EGFR and HR 1.67, 95% CI 1.34-2.08 for HER-2/neu). Meta-regression analysis for p53 showed that FIGO stage distribution influenced study outcome. For EGFR and HER-2/neu, considerable publication bias was present.

CONCLUSIONS

Although p53, EGFR and HER-2/neu status modestly influences survival, these markers are, by themselves, unlikely to be useful as prognostic markers in clinical practice. Our study highlights the need for well-defined, prospective clinical trials and more complete reporting of results of prognostic factor studies.

Cdc7 kinase is a predictor of survival and a novel therapeutic target in epithelial ovarian carcinoma

PURPOSE

There is a lack of prognostic and predictive biomarkers in epithelial ovarian carcinoma, and the targeting of oncogenic signaling pathways has had limited impact on patient survival in this highly heterogeneous disease. The origin licensing machinery, which renders chromosomes competent for DNA replication, acts as a convergence point for upstream signaling pathways. We tested the hypothesis that Cdc7 kinase, a core component of the licensing machinery, is predictive of clinical outcome and may constitute a novel therapeutic target in epithelial ovarian carcinoma.

EXPERIMENTAL DESIGN

A total of 143 cases of ovarian cancer and 5 cases of normal ovary were analyzed for Cdc7 protein expression dynamics and clinicopathologic features. To assess the therapeutic potential of Cdc7, expression was down-regulated by RNA interference in SKOV-3 and Caov-3 ovarian cancer cells.

RESULTS

Increased Cdc7 protein levels were significantly associated with arrested tumor differentiation (P = 0.004), advanced clinical stage (P = 0.01), genomic instability (P < 0.001), and accelerated cell cycle progression. Multivariate analysis shows that Cdc7 predicts disease-free survival independent of patient age, tumor grade and stage (hazard ratio, 2.03; confidence interval, 1.53-2.68; P < 0.001), with the hazard ratio for relapse increasing to 10.90 (confidence interval, 4.07-29.17) for the stages 3 to 4/upper Cdc7 tertile group relative to stages 1 to 2/lower Cdc7 tertile tumors. In SKOV-3 and Caov-3 cells, Cdc7 siRNA knockdown triggered high levels of apoptosis, whereas untransformed cells arrest in G(1) phase and remain viable.

CONCLUSIONS

Our findings show that Cdc7 kinase predicts survival and is a potent anticancer target in epithelial ovarian carcinoma, highlighting its potential as a predictor of susceptibility to small molecule kinase inhibitors currently in development.

Functional genomics and proteomics approaches to study the ERBB network in cancer

Substantial progress in functional genomic and proteomic technologies has opened new perspectives in biomedical research. The sequence of the human genome has been mostly determined and opened new visions on its complexity and regulation. New technologies, like RNAi and protein arrays, allow gathering knowledge beyond single gene analysis. Increasingly, biological processes are studied with systems biological approaches, where qualitative and quantitative data of the components are utilized to model the respective processes, to predict effects of perturbations, and to then refine these models after experimental testing. Here, we describe the potential of applying functional genomics and proteomics, taking the ERBB family of growth-factor receptors as an example to study the signaling network and its impact on cancer.

Status of HER1 and HER2 in peritoneal, ovarian and colorectal endometriosis and ovarian endometrioid adenocarcinoma

A role for the EGF system, in particular HER1 and 2, in growth of the endometrium has been suggested but HER1 and 2 have not been studied in all locations of endometriosis and in ovarian endometrioid adenocarcinoma (OEC) which is a rare form of malignant transformation of endometriosis. Immunohistochemistry (IHC) was used for studying HER1 and HER2 in ovarian (n = 10), peritoneal (n = 10), colorectal endometriosis (n = 20) and OEC (n = 10). Fluorescent in situ hybridisation (FISH) was used for analysing the status of HER2 gene in colorectal endometriosis and OEC. All samples were negative for HER2 in both glandular and stromal cells and in glandular cells for HER1 by IHC. In 15 out of 20 colorectal endometriosis, there was a weak expression in stromal cells. Following FISH, two colorectal samples had a partial 17 aneusomy and three OEC, a 17 polysomy. The other samples were 17 disomic without HER2 amplification; HER1 and 2 do not seem to have a role in endometriosis physiopathology.

Preclinical studies and clinical utilization of monoclonal antibodies in epithelial ovarian cancer

OBJECTIVE

To present an overview of selected monoclonal antibodies (mAbs) that have been studied in epithelial ovarian cancer with a focus on combination treatment with conventional chemotherapy.

METHODS

The authors perform a narrative review of the literature. Preclinical studies that provided rationale for mAb use are examined, and selected clinical trials that evaluated efficacy and tolerability are reviewed.

RESULTS

Numerous mAbs have been utilized in epithelial ovarian cancer, including bevacizumab (anti-vascular endothelial growth factor), trastuzumab (anti-human epidermal growth factor-2), cetuximab (anti-epidermal growth factor receptor), and oregovomab (anti-CA125). Favorable preclinical results have lead to the development of a number of clinical trials. Side-effects have been minimal and combination therapy has been well-tolerated. Efficacy has been variable in the clinical trials.

CONCLUSIONS

Targeted treatment with mAbs in conjunction with cytotoxic chemotherapy has been an important research area during the last decade. This therapeutic approach holds promise for improved outcomes in patients with ovarian cancer.

The impact of T-cell immunity on ovarian cancer outcomes

Ovarian cancer remains a challenging disease for which improved treatments are urgently needed. Most patients present with advanced disease that is highly responsive to surgery combined with platinum- and taxane-based chemotherapy, with a state of minimal residual disease being achieved in many cases. However, chemotherapy-resistant recurrent tumors typically appear within 1-5 years and are ultimately fatal. Recently, several groups have shown that ovarian tumors are often infiltrated by activated T cells at the time of diagnosis, and patients with dense infiltrates of CD3+CD8+ T cells experience unexpectedly favorable progression-free and overall survival. Other cell types in the immune infiltrate oppose anti-tumor immunity, including CD4+CD25+FoxP3+ regulatory T cells, CD8+ regulatory T cells, macrophages, and dendritic cells. The composition of immune infiltrates is shaped by the expression of cytokines, chemokines, antigens, major histocompatibility complex molecules, and costimulatory molecules. The relationship between these various immunological factors is reviewed here with a strong emphasis on outcomes data so as to create a knowledge base that is well grounded in clinical reality. With improved understanding of the functional properties of natural CD8+ T-cell responses to ovarian cancer, there is great potential to improve clinical outcomes by amplifying host immunity.

Genome-wide copy number alterations detection in fresh frozen and matched FFPE samples using SNP 6.0 arrays

SNP arrays offer the opportunity to get a genome-wide view on copy number alterations and are increasingly used in oncology. DNA from formalin-fixed paraffin-embedded material (FFPE) is partially degraded which limits the application of those technologies for retrospective studies. We present the use of Affymetrix GeneChip SNP6.0 for identification of copy number alterations in fresh frozen (FF) and matched FFPE samples. Fifteen pairs of adenocarcinomas with both frozen and FFPE embedded material were analyzed. We present an optimization of the sample preparation and show the importance of correcting the measured intensities for fragment length and GC-content when using FFPE samples. The absence of GC content correction results in a chromosome specific "wave pattern" which may lead to the misclassification of genomic regions as being altered. The highest concordance between FFPE and matched FF were found in samples with the highest call rates. Nineteen of the 23 high level amplifications (83%) seen using FF samples were also detected in the corresponding FFPE material. For limiting the rate of "false positive" alterations, we have chosen a conservative False Discovery Rate (FDR). We observed better results using SNP probes than CNV probes for copy number analysis of FFPE material. This is the first report on the detection of copy number alterations in FFPE samples using Affymetrix GeneChip SNP6.0.

[Ovarian carcinoma. Do the subtypes reflect different diseases?]

Lack of therapeutic options and poor reproducibility of histopathological subtypes have been the reasons that ovarian carcinomas are currently treated as monolithic entity. Histopathological grading is used to identify those patients who can be spared adjuvant therapy. With slight modifications of the WHO based subtype classification we have shown that subtypes (i.e. serous, endometrioid, clear cell, mucinous) can be reproducibly used to stratify patients according to disease-specific survival. As these pathologically identifiable subtypes have different epidemiologic and genetic risk factors, precursor lesions, molecular abnormalities and clinical behaviour, screening and management strategies have to be subtype-specific.

Critical molecular abnormalities in high-grade serous carcinoma of the ovary

Ovarian carcinomas show more morphological heterogeneity than adenocarcinomas of any other body site. It has recently become clear that the morphologically defined subtypes of ovarian carcinoma are distinct diseases, with different risk factors, molecular events during oncogenesis, likelihood of spread, responses to chemotherapy, and outcomes. This review focuses on molecular abnormalities (in genes expressing BRCA1/2, TP53 and RB1/CCND1/CDKN2A/E2F) found in high-grade serous carcinomas of the ovary, which account for most ovarian cancer deaths. These highly aggressive but chemosensitive tumours are associated with perturbation of molecular pathways leading to genomic instability and extreme mutability and present unique challenges in oncological research and practice.