Rates of topoisomerase II-alpha and HER-2 gene amplification and expression in epithelial ovarian carcinoma

Nucleic Acid Tests for Clinical Translation

Nucleic acids, including deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), are natural biopolymers composed of nucleotides that store, transmit, and express genetic information. Overexpressed or underexpressed as well as mutated nucleic acids have been implicated in many diseases. Therefore, nucleic acid tests (NATs) are extremely important. Inspired by intracellular DNA replication and RNA transcription, in vitro NATs have been extensively developed to improve the detection specificity, sensitivity, and simplicity. The principles of NATs can be in general classified into three categories: nucleic acid hybridization, thermal-cycle or isothermal amplification, and signal amplification. Driven by pressing needs in clinical diagnosis and prevention of infectious diseases, NATs have evolved to be a rapidly advancing field. During the past ten years, an explosive increase of research interest in both basic research and clinical translation has been witnessed. In this review, we aim to provide comprehensive coverage of the progress to analyze nucleic acids, use nucleic acids as recognition probes, construct detection devices based on nucleic acids, and utilize nucleic acids in clinical diagnosis and other important fields. We also discuss the new frontiers in the field and the challenges to be addressed.

Integrated bioinformatics analysis for the screening of hub genes and therapeutic drugs in ovarian cancer

Background

Ovarian cancer (OC) ranks fifth as a cause of gynecological cancer-associated death globally. Until now, the molecular mechanisms underlying the tumorigenesis and prognosis of OC have not been fully understood. This study aims to identify hub genes and therapeutic drugs involved in OC.

Methods

Four gene expression profiles (GSE54388, GSE69428, GSE36668, and GSE40595) were downloaded from the Gene Expression Omnibus (GEO), and the differentially expressed genes (DEGs) in OC tissues and normal tissues with an adjusted P-value < 0.05 and a |log fold change (FC)| > 1.0 were first identified by GEO2R and FunRich software. Next, Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) analyses were performed for functional enrichment analysis of these DEGs. Then, the hub genes were identified by the cytoHubba plugin and the other bioinformatics approaches including protein-protein interaction (PPI) network analysis, module analysis, survival analysis, and miRNA-hub gene network construction was also performed. Finally, the GEPIA2 and DGIdb databases were utilized to verify the expression levels of hub genes and to select the candidate drugs for OC, respectively.

Results

A total of 171 DEGs were identified, including 114 upregulated and 57 downregulated DEGs. The results of the GO analysis indicated that the upregulated DEGs were mainly involved in cell division, nucleus, and protein binding, whereas the biological functions showing enrichment in the downregulated DEGs were mainly negative regulation of transcription from RNA polymerase II promoter, protein complex and apicolateral plasma membrane, and glycosaminoglycan binding. As for the KEGG-pathway, the upregulated DEGs were mainly associated with metabolic pathways, biosynthesis of antibiotics, biosynthesis of amino acids, cell cycle, and HTLV-I infection. Additionally, 10 hub genes (KIF4A, CDC20, CCNB2, TOP2A, RRM2, TYMS, KIF11, BIRC5, BUB1B, and FOXM1) were identified and survival analysis of these hub genes showed that OC patients with the high-expression of CCNB2, TYMS, KIF11, KIF4A, BIRC5, BUB1B, FOXM1, and CDC20 were statistically more likely to have poorer progression free survival. Meanwhile, the expression levels of the hub genes based on GEPIA2 were in accordance with those based on GEO. Finally, DGIdb database was used to identify 62 small molecules as the potentially targeted drugs for OC treatment.

Conclusions

In summary, the data may produce new insights regarding OC pathogenesis and treatment. Hub genes and candidate drugs may improve individualized diagnosis and therapy for OC in future.

Expression of p53 and HER2/Neu in Kenyan Women With Primary Ovarian Carcinoma

Ovarian carcinomas are a leading cause of cancer mortality among women. Two of the more commonly described markers of prognostic significance in primary ovarian carcinomas are p53 and HER2/neu. Overexpression of both markers is associated with poor prognosis. This study aimed to determine the frequency and pattern of p53 and HER2/neu expression in primary ovarian carcinomas in Kenyan women and to describe the clinical and pathologic features of ovarian carcinomas diagnosed at 3 different hospitals in Kenya. Primary ovarian carcinomas diagnosed at the Departments of Pathology at Aga Khan University Hospital, Nairobi; the Aga Khan Hospital, Kisumu; and the AIC Kijabe Hospital in Kenya over a period of 3 years from January 2009 to December 2011 were recorded. Sixty-seven ovarian carcinomas were identified and blocks retrieved from archives. Hematoxylin-eosin-stained slides of these were reviewed and appropriate sections were stained for p53 and HER2/neu using standard immunohistochemical techniques. The primary outcome was presence and intensity of staining for p53 and HER2/neu. The most frequent malignancy was serous carcinoma. A total of 43.3% (95% confidence interval, 32.1%-55.2%) of carcinomas were positive for p53, and 13.4% (95% confidence interval, 7.2%-23.6%) were positive for HER2/neu. Serous carcinoma and adenocarcinoma, not otherwise specified were more likely to be positive for p53. There was no association noted between the histologic grade or pathologic stage and positivity for either p53 or HER2/neu. The expression of p53 and HER2/neu in primary ovarian carcinomas in Kenyan women is not different from that described in the literature.

TOP2A gene copy gain predicts response of epithelial ovarian cancers to pegylated liposomal doxorubicin: TOP2A as marker of response to PLD in ovarian cancer

OBJECTIVE

The treatment of platinum resistant/refractory epithelial ovarian cancer (EOC) is a challenge for oncologists. One of the most utilized drugs in these patients is pegylated liposomal doxorubicin (PLD). As PLD is active only in a small subset of patients and causes side effects, selection of responsive patients is an unmet need and might be guided by the status of the DNA topoisomerase II alpha (TOP2A) that is poisoned by the drug.

METHODS

From 176 ovarian cancers treated in three institutions, we selected 38 patients treated with PLD monotherapy as second/third line of treatment. TOP2A gene copies were measured using Fluorescent In Situ Hybridization (FISH) and expression evaluated using immunohistochemistry. Patients' derived xenografts (PDXs) of ovarian cancers were used to assess the correlation between TOP2A protein expression and response to PLD.

RESULTS

Clinical data showed that TOP2A gene gain that is paralleled by increased expression of the protein, was associated with a higher probability of clinical benefit from PLD. Treatment of PDXs demonstrated that only xenografts showing a high percentage of TOP2A expressing cells underwent tumor shrinkage when treated with PLD.

CONCLUSIONS

These data show that TOP2A gene gain and protein over-expression might predict activity of PLD in platinum resistant/refractory EOC.

Expressions of fatty acid synthase and HER2 are correlated with poor prognosis of ovarian cancer

The present study was designed to explore the cross talk between fatty acid synthase (FASN) and HER2 (ErbB2) in ovarian cancer. A total of 60 ovarian cancer patients and 15 normal ovarian tissues were enrolled. Tissue array was conducted by using a tissue microarray instrument. Immunohistochemistry was performed to quantify the expressions of HER2 and FASN. The FASN was detected to be distributed in the cell cytoplasm and was significantly correlated with cancer grade (p = 0.000) and FIGO staging (p = 0.000). Patients with FASN overexpression in ovarian cancer tend to have a worse overall survival rate (p = 0.000). HER2 was also stained to be distributed in the cell cytoplasm associated with higher expression in high-grade cancer. It was also disclosed that FASN expression level is not correlated with HER2 status in ovarian cancer. These results for the first time indicated that a cross talk in FASN and HER2 expressions might be associated with prognosis in malignant ovarian cancer.

Targeting signaling pathways in epithelial ovarian cancer

Ovarian carcinoma (OC) is the most lethal gynecological malignancy. Response to platinum-based chemotherapy is poor in some patients and, thus, current research is focusing on new therapy options. The various histological types of OC are characterized by distinctive molecular genetic alterations that are relevant for ovarian tumorigenesis. The understanding of these molecular pathways is essential for the development of novel therapeutic strategies.

P53, MAPK, topoisomerase II alpha and Ki67 immunohistochemical expression and KRAS/BRAF mutation in ovarian serous carcinomas

Background

We investigated the immunohistochemical expression of p53, MAPK, topoisomerase II alpha (topoII alpha) and Ki67 in ovarian serous carcinomas (OSCs) along with mutational analysis for KRAS and BRAF.

Methods

Eighty one cases of OSCs were reviewed and examined immunohistochemically using antibodies against p53, MAPK, topoII alpha and Ki67. Staining was evaluated as a percentage of immunopositive cells with cut-off levels at 10% for p53 and topoII alpha, and 5% for MAPK. The Ki67 immunoexpression was assessed by means of Olympus Image Analysis System as a percentage of immunopositive cells in 1000 tumor cells. KRAS and BRAF mutational analysis was performed on 73 available microdissected samples.

Results

Of 81 cases of OSCs 13.6% were of low-grade and 86.4% were of high-grade morphology. In the high-grade group there was a significantly higher immunoexpression of p53 (P < 0.001) and topoII alpha (P = 0.001), with Ki67 median 56.5 vs. 19 in low-grade group (P < 0.001). The difference in immunoexpression of active MAPK between low- and high-grade group was also significant (P = 0.003). MAPK positive immunostaining was detected in 63.6% of low-grade vs. 17.1% of high-grade OSCs. The frequency of KRAS mutation was significantly higher in low-grade as compared to high-grade group (P = 0.006). None of the samples had BRAF mutation. In addition, we detected positive MAPK immunoexpression in 13/59 samples with wild-type KRAS, suggesting that activation of MAPK pathway is not ultimately related either to KRAS or BRAF mutation. Seven morphologically high-grade samples (11.7%) showed both KRAS mutation and p53 immunopositivity.

Conclusions

Although this study is limited by its humble number of low-grade samples, our data fit the proposed dualistic pathway of ovarian carcinogenesis. Mutational analysis for KRAS and BRAF discloses some possible interactions between different tumorigenic pathways of low- and high-grade carcinomas. Immunohistochemical staining for MAPK was not sufficiently sensitive, nor specific, to precisely predict the KRAS mutation. However, it appears to be quite reliable in ruling out a KRAS mutation if the staining is negative.

Virtual Slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/9283563368804632

Zusammenfassung

Hintergrund

Wir untersuchten die Immunohistochemische Expression der p53, MAPK, topoisomerase II alpha (topoII alpha) und Ki67 in Ovarialkarzinomen (OSCs) anbei mit Mutationsanalyse für KRAS und BRAF.

Methode

81 OSCs Fälle wurden analysiert und Immunohistochemisch untersucht mit Antikörper gegen p53, MAPK, topoII alpha und Ki67. Die Färbung war ausgewertet als der Prozent von immunopositiven Zellen mit den “cut-of” Niveau an 10% für p53 und topoII alpha und 5% für MAPK. Die Ki67 Expression war bewertet mittels Olympus Image Analysis System als der Prozent von immunopositiven Zellen in 1000 Tumorzellen. KRAS and BRAF Mutationsanalyse wurde in 73 verfügbaren microdissections Stichproben aufgeführt.

Ergebnisse

Von 81 OSCs Fälle 13.6% zeigte “low-grade” und 86.4% “high-grade” Morphologie. In der “high-grade” Gruppe war eine statistisch bedeutende höhere Expression von p53 (P < 0.001) und topoII alpha (P = 0.001) mit Ki67 median von 56.5 im Gegensatz zu 19 in der “low-grade” Gruppe (P < 0.001). Die Differenz in Immunoexpression von aktiver MAPK zwischen der “low-grade” und “high-grade” Gruppe war statistisch bedeutend (P = 0.003). MAPK positive Expression war in 63.6% der “low-grade” im Gegensatz von 17.1% der “high-grade” Karzinoms bemerkt. Die Häufigkeit der KRAS Mutation war bedeutend höher in “low-grade” im Verglich zu der “high-grade” Gruppe (P = 0.006). Keiner der Stichproben hate BRAF Mutation. Wir haben auch eine positive MAPK Expression in 13/59 der Stichproben mit “wild-type” KRAS bemerkt, was sugeriert das die Aktivation des MAPK Pfads ist nicht letztmalig mit KRAS oder BRAF verbunden. Sieben der “high-grade” Stichproben (11.7%) waren KRAS Mutation und p53 Expression positive.

Schlussworte

Obwohl diese Studie mit bescheiden Nummer von “low-grade” Stichproben limitiert ist, unsere Daten passen in das dualistische Modell von Ovarial Karzinogenesis. Mutationsanalyse für KRAS und BRAF enthüllen einige mögliche Interaktionen zwischen verschieden tumorigenen Wege von “low”- and “high-grade” Karcinomen.

Die Immunohistochemische Expression für MAPK war nicht empfindlich oder spezifisch genüg um den KRAS mutations Status des Tumor genau vorauszusagen.

Es scheint das die MAPK Expression ziemlich verlässlich ist in ausschließen der KRAS Mutation, wenn die Expression negative ist.

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.

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.

Therapeutic advances in women's cancers

Cytotoxic therapy and surgery have improved outcomes for patients with gynecologic malignancies over the last twenty years, but women's cancers still account for over ten percent of cancer related deaths annually. Insights into the pathogenesis of cancer have led to the development of drugs that target molecular pathways essential to tumor survival including angiogenesis, DNA repair, and apoptosis. This review outlines several of the promising new biologically targeted drugs currently being tested to treat gynecologic malignancies.

Clinical significance of P-glycoprotein and topoisomerase II expression in gastric cancer

AIM: To investigate the correlation of P-glycoprotein (P-gp) and topoisomerase II (Topo II) protein expression with the clinicopathological characteristics of gastric cancer.

METHODS: A total of 1 107 surgical specimens of gastric cancer were collected from patients treated at Fuzhou General Hospital of Nanjing Military Command from January 2006 to August 2009. The protein expression of P-gp and Topo II in 775 specimens from gastric cancer patients having complete clinical data was examined by immunohistochemistry.

RESULTS: The overexpression rates of P-gp and Topo II proteins in patients with gastric cancer were 52.39% (406/775) and 58.45% (453/775), respectively. P-gp protein overexpression was associated with depth of invasion, TNM stage, and lymph node metastasis (all P < 0.05), but not with sex, age, tumor site, histotype, differentiation, and distant metastasis (all P > 0.05). Topo II protein overexpression was associated with age, tumor site, depth of invasion, histotype, differentiation, and lymph node metastasis (all P < 0.05), but not with sex, TNM stage and distant metastasis (all P > 0.05).

CONCLUSION: Detection of P-gp and Topo II protein expression may be used to assess the malignant biological behavior and prognosis of gastric cancer and can therefore provide a theoretical basis for choice of chemotherapy drugs for gastric cancer.

Topoisomerase II alpha as a universal tumor antigen: antitumor immunity in murine tumor models and H-2K(b)-restricted T cell epitope

Topoisomerase II alpha (Top2alpha) is an attractive candidate to be used as a tumor antigen for cancer immunotherapy, because it is abundantly expressed in various tumors and serves as a target for a number of chemotherapeutic agents. In this study, we demonstrated the immunogenicity of Top2alpha, using dendritic cells (DC) electroporated with RNA encoding the Top2alpha C-terminus (Top2alphaCRNA/DC). Top2alphaCRNA/DC were able to demonstrate in vitro stimulation of T cells from mice that were previously vaccinated with Top2alpha-expressing tumor lysate-pulsed DC. Vaccination with Top2alphaCRNA/DC induced Top2alpha-specific T cell responses in vivo as well as antitumor effects in various murine tumor models including MC-38, B16F10, and GL26. DC pulsed with p1327 (DSDEDFSGL), defined as an epitope presented by H-2K(b), also induced Top2alpha-specific immune responses and antitumor effects. Based on these data, Top2alpha is suggested to be a universal target for cancer immunotherapy.

HER2 overexpression and amplification is present in a subset of ovarian mucinous carcinomas and can be targeted with trastuzumab therapy

BACKGROUND

The response rate of ovarian mucinous carcinomas to paclitaxel/carboplatin is low, prompting interest in targeted molecular therapies. We investigated HER2 expression and amplification, and the potential for trastuzumab therapy in this histologic subtype of ovarian cancer.

METHODS

HER2 status was tested in 33 mucinous carcinomas and 16 mucinous borderline ovarian tumors (BOT)). Five cases with documented recurrence and with tissue from the recurrence available for testing were analyzed to determine whether HER2 amplification status changed over time. Three prospectively identified recurrent mucinous ovarian carcinomas were assessed for HER2 amplification and patients received trastuzumab therapy with conventional chemotherapy.

RESULTS

Amplification of HER2 was observed in 6/33 (18.2%) mucinous carcinomas and 3/16 (18.8%) BOT. HER2 amplification in primary mucinous carcinomas was not associated with an increased likelihood of recurrence. The prospectively identified recurrent mucinous carcinomas showed overexpression and amplification of HER2; one patient's tumor responded dramatically to trastuzumab in combination with conventional chemotherapy, while another patient experienced an isolated central nervous system recurrence after trastuzumab therapy.

CONCLUSION

HER2 amplification is relatively common in ovarian mucinous carcinomas (6/33, 18.2%), although not of prognostic significance. Trastuzumab therapy is a treatment option for patients with mucinous carcinoma when the tumor has HER2 amplification and overexpression.

Associations between ERBB2 amplification and progression-free survival and overall survival in advanced stage, suboptimally-resected epithelial ovarian cancers: a Gynecologic Oncology Group Study

OBJECTIVE(S)

The Gynecologic Oncology Group (GOG) examined the association between ERBB2 amplification and clinical covariates, tumor response, disease status post-chemotherapy, progression-free survival (PFS), and overall survival (OS) in epithelial ovarian cancer (EOC).

METHODS

Women with suboptimally-resected, advanced stage EOC who participated in GOG-111, a multi-center randomized phase III trial of cyclophosphamide+cisplatin versus paclitaxel+cisplatin, and provided a tumor block through the companion protocol GOG-9404 were eligible. ERBB2 amplification was examined using fluorescence in situ hybridization (FISH) with probes for ERBB2 and the centromere of chromosome 17 (CEP17).

RESULTS

ERBB2 amplification, defined as >2 copies of ERBB2/CEP17, was a rare event in EOC with 7% (9/133) of women exhibiting between 2.2 and 33.7 copies of ERBB2/CEP17, and was not associated with patient age, race, GOG performance status, stage, cell type, grade, measurable disease status, volume of ascites, tumor response or disease status post-chemotherapy. Women with >2 verses < or =2 copies of ERBB2/CEP17 did not have a reduced risk of disease progression (hazard ratio [HR]=0.56; 95% confidence interval [CI]=0.27-1.16; p=0.120) or death (HR=0.57; 95% CI=0.26-1.23; p=0.152), and ERBB2 amplification was not an independent prognostic factor for PFS or OS. ERBB2 amplification, defined as >4 copies of ERBB2/nuclei, was observed in 9% (12/133) of women with levels ranging from 4.2 to 49.2 copies of ERBB2/nuclei, and was associated with older age and volume of ascites, but not with the other clinical covariates or outcome.

CONCLUSION(S)

ERBB2 amplification is a rare event and has no predictive or prognostic value in suboptimally-resected, advanced stage EOC treated with platinum-based combination chemotherapy.

Prognostic role of topoisomerase-IIalpha in advanced ovarian cancer patients

To our knowledge, very few data about the role of Topoisomerase IIalpha (TOPO-IIalpha), an enzyme involved in critical steps of tumour cell proliferation and chemoresistance are currently available in ovarian cancer patients. The aim of this study was to investigate the prognostic value of TOPO-IIalpha expression in a large, single institution series of 96 primary untreated advanced ovarian cancer patients admitted to the Gynecologic Oncology Unit, Catholic University of Campobasso and Rome. Immunohistochemistry was carried out by using the MoAb anti-human TOPO-IIalpha antibody (clone Ki-S1). TOPO-IIalpha immunoreaction was observed in 70 out of 96 cases (72.9%), and the percentages of positively stained cells ranged between 1 and 83% (median=10%). There was no association with clinico-pathological parameters. During the follow up period, progression and death of disease were observed in 76 (79.2%) and 45 (46.9%) cases. A statistically significant direct association between the percentages of positively immunostained tumour cells and the relative risk of death was observed (chi(2)=6.6, P-value=0.0101). In multivariate analysis, only platinum resistance, advanced stage of disease and high levels of TOPO-IIalpha expression retained an independent negative prognostic role for OS. The unfavourable role of high TOPO-IIalpha expression was maintained only in the subgroup of platinum resistant recurrent ovarian cancer patients, be TOPO-IIalpha expression evaluated as continuous variable (chi(2)=5.1, P-value=0.024), or by means of the defined cutoff point. Our study suggests that the assessment of TOPO-IIalpha could be helpful to identify poor prognosis platinum-resistant ovarian cancer patients, potentially candidates to investigational agents.

Clinical implications of the ErbB/epidermal growth factor (EGF) receptor family and its ligands in ovarian cancer

The ERBB or EGF receptor (EGFR) proto-oncogene family, which consists of four structurally-related transmembrane receptors (i.e., EGFR, ErbB2, ErbB3, and ErbB4), plays an etiological role in the molecular pathogenesis of cancer and is a key therapeutic target in many types of cancer, including ovarian cancer. These ErbB/EGF receptor tyrosine kinases play important physiologic roles in cell proliferation, survival, adhesion, motility, invasion, and angiogenesis. It is, therefore, not surprising that gene amplification, genetic mutation, and altered transcription/translation result in aberrant ErbB/EGF receptor expression and/or signal transduction, contributing to the development of malignant transformation. Clinically, the diagnostic, prognostic, and theragnostic significance of any single ErbB receptor and/or ErbB ligand is controversial, but generally, ErbB receptor overexpression has been correlated with poor prognosis and decreased therapeutic responsiveness in ovarian cancer patients. Thus, anticancer agents targeting ErbB/EGF receptors hold great promise for personalized cancer treatment. Yet, challenges remain in designing prospective clinical trials to assess the clinical utility of ErbB receptors and their ligands to diagnose cancer; to predict progression-free and overall survival, therapeutic responsiveness, and disease recurrence; and to monitor treatment responsiveness. Here, we review the tissue expression and serum biomarker studies that have evaluated the diagnostic, prognostic, and theragnostic utility of ErbB/EGF receptors, their circulating soluble isoforms (sEGFR/sErbBs), and their cognate ligands in ovarian cancer patients.

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

BACKGROUND

Despite a typically good response to first-line combination chemotherapy, the prognosis for patients with advanced ovarian cancer remains poor because of acquired chemoresistance. The use of targeted therapies such as trastuzumab may potentially improve outcomes for patients with ovarian cancer. HER2 overexpression/amplification has been reported in ovarian cancer, but the exact percentage of HER2-positive tumors varies widely in the literature. In this study, HER2 gene status was evaluated in a large, multicentric series of 320 patients with advanced ovarian cancer, including 243 patients enrolled in a multicenter prospective clinical trial of paclitaxel/carboplatin-based chemotherapy.

METHODOLOGY/PRINCIPAL FINDINGS

The HER2 status of primary tumors and metastases was evaluated by both immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) analysis of paraffin-embedded tissue on conventional slides. The prognostic impact of HER2 expression was analyzed. HER2 gene was overexpressed and amplified in 6.6% of analyzed tumors. Despite frequent intratumoral heterogeneity, no statistically significant difference was detected between primary tumors and corresponding metastases.

CONCLUSIONS/SIGNIFICANCE

Our results show that the decision algorithm usually used in breast cancer (IHC as a screening test, with equivocal results confirmed by FISH) is appropriate in ovarian cancer. In contrast to previous series, HER2-positive status did not influence outcome in the present study, possibly due to the fact that patients in our study received paclitaxel/carboplatin-based chemotherapy. This raises the question of whether HER2 status and paclitaxel sensitively are linked.

Effect of HER-2/neu overexpression on chemoresistance and prognosis in ovarian carcinoma

AIM

To investigate the effect of HER-2/neu protein overexpression on chemoresistance and prognosis in patients with epithelial ovarian carcinoma.

METHODS

A total of 141 ovarian carcinoma tissues surgically resected between 1987 and 2003 were assessed by immunohistochemistry (IHC). The characteristic of the patients and immunohistochemical results were compared by chi2-test. Survival analysis was performed by the Kaplan-Meier method and the log-rank test.

RESULTS

HER-2/neu overexpression was detected in 18 cases (12.8%). There were no significant differences in histopathological subtypes (P = 0.3550), FIGO stages (P = 0.8858), or residual tumor size at first surgery (P = 0.6607) between the cases with HER-2/neu overexpression and the cases without HER-2/neu overexpression. Among the 58 cases which responded to chemotherapy, only five cases (8.6%) showed HER-2/neu overexpression. However, among the 38 cases which did not respond to chemotherapy, eight cases (21.1%) showed HER-2/neu overexpression. Overexpression of HER-2/neu had a tendency to relate with chemoresistance of epithelial ovarian carcinoma, but there were no statistically significant differences (P = 0.0817). No association was observed between HER-2/neu overexpression and cumulative survival rate (P = 0.4970).

CONCLUSIONS

The results of the current study show that although HER-2/neu overexpression has a tendency to be associated with chemoresistance, it can not be a prognostic factor for the patients with epithelial ovarian carcinoma.

Evaluation of topoisomerase IIa expression in pancreatic ductal adenocarcinoma: a pilot study using chromogenic in situ hybridization and immunohistochemistry on tissue microarrays

BACKGROUND/AIMS

To co-evaluate topoisomerase IIa (Topo IIa) protein expression and gene status in pancreatic ductal adenocarcinoma, determining the potential prognostic impact of its alterations.

METHODS

Using tissue microarrays, 50 sporadic, primary pancreatic ductal adenocarcinomas were cored twice and re-embedded into one paraffin block with a core diameter of 1 mm. Immunohistochemistry and chromogenic in situ hybridization were performed in serial tissue sections for the detection of protein expression levels, chromosome 17 and Topo IIa gene status, respectively. Finally using a semi-automated image analysis system we evaluated the levels of protein expression.

RESULTS

A significant proportion of the tumors showed Topo IIa overexpression (32/50 or 64%). Gene amplification and deletion were detected in 9 and 4 cases, respectively, associated with protein overexpression. Aneuploidy regarding chromosome 17 was observed in 19/50 tumors and correlated with poor survival rate (Cox regression test: p = 0.001). Topo IIa protein expression was strongly correlated with stage (p = 0.021) and grade (p = 0.034).

CONCLUSIONS

Topo IIa gene amplification correlates with protein overexpression, but not vice versa. This is a crucial observation for the application of targeted chemotherapies, such as anthracyclines, only in subgroups of patients, according to molecular deregulation criteria and not only to immunohistochemical results. Also, chromosome 17 and not Topo IIa gene instability can be used as a potential independent prognostic factor.

The prognostic importance of cyclooxygenase 2 and HER2 expression in epithelial ovarian cancer

Both cyclooxygenase 2 (COX2) and human epidermal growth factor receptor 2 (HER2, also called c-erbB-2) overexpression have been related to a worse prognosis in epithelial ovarian cancer (EOC), but the data are conflicting and the percentage of tumors with overexpression varies widely in different studies. The aim of this study was to investigate the potential prognostic value of COX2 and HER2 expression in EOC. A further purpose was to investigate a possible coexpression of the two markers, and finally, to elucidate the agreement between fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) for evaluation of the HER2 status in EOC. Immunostaining was performed for COX2/HER2 together with FISH analysis for HER2 gene amplification in 160 patients with EOC, FIGO stages IIB-IV. Follow-up was more than 10 years. COX2 overexpression was found in 20.0% of the tumors. With HER2 staining, 64.4% were scored as 0, 24.4% as 1+, 6.9% as 2+, and 4.4% as 3+. Median survival time for COX2-negative tumors was 21.6 versus 36 months for COX2-positive tumors. The longer survival for COX2 positive was significant by both univariate analysis (P= 0.015) and multivariate analysis (P= 0.025). Positive immunostaining for HER2 was associated with poor overall survival (P= 0.03). Agreement between IHC and FISH was seen in all cases (P < 0.0000001). With long-term observation, patients with negative COX2 expression had significantly shorter survival compared to patients with COX2-positive tumors. Positive HER2 expression also notified a grave prognosis, but the low rate of overexpression reduces its potential clinical application.

In vivo tracking of macrophage activated killer cells to sites of metastatic ovarian carcinoma

Radio-labelling of blood cells is an established technique for evaluating in vivo migration of normal cells to sites of pathology such as infection and haemorrhage. A limitation of cellular immunotherapies to induce anti-tumour responses is in part due to the uncertain ability of cellular effectors to reach their intended target. We extended the approach of cell radiolabelling to accurately examine the in vivo distribution of cellular immunotherapy with ex-vivo macrophage activated killer (MAK) cells. We describe the use of two methods of cell labelling for tracking the destination of autologous-derived macrophage activated killer (MAK) cells linked to the bi-specific antibody MDX-H210 delivered either by intravenous (i.v.) or intraperitoneal (i.p.) injection in ten patients with peritoneal relapse of epithelial ovarian carcinoma. Our results demonstrate the feasibility of generating high numbers and purity of GMP quality MAK cells, which can be radiolabelled with (18)F-FDG or (111)In-oxime. MAK cell administration produced minimal infusional toxicity and demonstrated a reproducible pattern of in vivo distribution and active in vivo tracking to sites of known tumour following 8 of 16 i.v. infusions or 4 of 6 i.p. infusions. However, the leakage of (18)F-FDG limited the ability to confidently confirm the tracking of MAK cells to tumour in all cases and improved PET labels are required. The addition of MDX-H210 bispecific antibody did not alter the distribution of cells to tumour sites, but did accelerate the clearance of i.v. administered MAK cells from the pulmonary circulation. This data demonstrates that cellular cancer immunotherapies may be successfully delivered to the sites of active tumour following either i.v. or i.p. injection in a proportion of patients with metastatic cancer. Incorporation of tracking studies in early cycles of cellular immunotherapy may allow selection of patients who demonstrate successful targeting of the immunotherapy for ongoing treatment.

The 17q12-q21 amplicon: Her2 and topoisomerase-IIalpha and their importance to the biology of solid tumours

Her2 and topoisomerase-IIalpha (T2A) gene amplification are separate events, although the latter is more frequently seen in Her2 amplified (34-90%) than in Her2 non-amplified (5-10%) tumours. There is a better correlation between Her2 amplification and protein overexpression in breast cancer (BC) than in other tumour types. This marker is also considered a powerful prognostic factor in BC, with similar data emerging in other solid tumours such as bladder, ovarian, endometrial, gastro-oesophageal and non-small cell lung cancer. Her2 amplification and/or overexpression are highly predictive of response to HER2-targeted compounds such as trastuzumab and lapatinib but have been inconsistent predictors of response to cytotoxic chemotherapy. There is also evidence that these tumours are relatively resistant to anti-oestrogen therapy (tamoxifen) but not to oestrogen deprivation (e.g. with aromatase inhibitors). T2A aberrations are uncommon events in solid tumours, with an overall prevalence of approximately 10%. T2A amplification has shown inconsistent correlation with T2A protein expression in preclinical and clinical studies, mainly because non-genetic events such as proliferation rate can also affect protein expression. Expression of T2A protein has not been shown to reliably predict response to T2A inhibitors, despite the fact that this enzyme is the direct target for these compounds. In BC, T2A amplification appears to be a good predictor of response to anthracyclines, but these data are still in the process of validation. The significance of T2A deletions is currently under investigation, but contrary to what was previously thought, it may also predict benefit from treatment with T2A inhibitors. The prognostic significance of T2A aberrations is currently unknown.

Altered expression pattern of topoisomerase IIalpha in ovarian tumor epithelial and stromal cells after platinum-based chemotherapy

OBJECTIVE

The aim of this study was to evaluate the expression of topoisomerase IIalpha (TOP2A) in epithelial and stromal cells of ovarian cancer.

METHODS

TOP2A expression was analyzed prospectively in normal and tumor epithelial and adjacent stromal cells using quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) after laser microdissection (n = 38), RNA in situ hybridization (n = 13), and immunohistochemistry (n = 69).

RESULTS

TOP2A mRNA was detected by RNA in situ hybridization in all ovarian cancer samples, with stronger hybridization signals in tumor epithelial cells compared to adjacent stromal cells. The same expression pattern was found by immunohistochemistry (P = .0001). Very interestingly, specific change was found in recurrent ovarian cancer after platinum-based chemotherapy: TOP2A expression decreased in tumor epithelial cells of recurrent ovarian cancer compared to primary ovarian cancer (P = .056), whereas it increased in tumor-adjacent stromal cells in carboplatin-treated recurrent tumors compared to primary ovarian cancer (P = .023).

CONCLUSION

TOP2A mRNA and protein expression in ovarian cancer exhibits specific patterns in tumor epithelial and adjacent stromal cells, which are differentially modulated after platinum-based chemotherapy. These data support the recently discovered importance of the stromal compartment in tumor progression and suggest that tumor stromal cells might be relevant to the development of chemotherapy resistance in ovarian cancer.

Targeting topoisomerase IIa in endometrial adenocarcinoma: a combined chromogenic in situ hybridization and immunohistochemistry study based on tissue microarrays

Topoisomerase IIa is a nucleic enzyme that affects the topological structure of DNA and also is a target for chemotherapy (ie, anthracyclines). In this study, we coevaluated its protein expression with chromosome 17 and gene status. Using tissue microarrays, 40 cases of sporadic, primary endometrial adenocarcinomas, 5 cases of atypical hyperplasia, and 5 cases of benign hyperplasia were obtained and reembedded into two paraffin blocks with a core diameter of 1 mm. Immunohistochemistry combined with chromogenic in situ hybridization was performed in 2 and 5 microm sections, respectively. Finally using a semiautomated Image Analysis System, we evaluated the levels of Nuclear labeling index of topoisomerase IIa expression. Statistical analysis was performed by SPSS version 11.0 software. The results indicate that chromosome 17 instability (aneuploidy in 7/40 cases) and Topo IIa gene deregulation (amplification in 3/40 and deletion in 1/40 cases) are significant genetic events correlated with biologic behavior in endometrial adenocarcinoma. Because protein overexpression was observed in a significant proportion of the tumors (18/40), detection of the specific gene deregulation mechanism is a crucial process for application of targeted chemotherapies, which are characterized by different levels of cardiotoxicity and other serious effects.

Gene amplification, mutation, and protein expression of EGFR and mutations of ERBB2 in serous ovarian carcinoma

EGFR and erbB-2 are targets for specific cancer therapy. The purpose of this study was to examine the frequency and clinicopathological correlations of gene amplification, protein expression, and mutations of EGFR and ERBB2 in serous carcinoma, the most common and aggressive type of ovarian cancer. Tissue microarray constructed of 398 carcinomas was examined by chromogenic in situ hybridization (CISH) and by immunohistochemistry. Cases with amplification of EGFR by CISH were further analyzed by fluorescence in situ hybridization. One hundred ninety-eight samples were analyzed for mutations in exons 18, 19, or 21 of EGFR and in exon 20 of ERBB2 using denaturating high-performance liquid chromatography and direct sequencing. Amplification of EGFR was present in 12% (41/333), low-level gain in 43% (144/333), and protein overexpression in 17% (66/379) of the tumors. Both increased copy number and overexpression of EGFR were associated with high tumor grade, greater patient age, large residual tumor size, high proliferation index, aberrant p53, and poor patient outcome. Furthermore, increased copy number of EGFR was associated with increased copy number of ERBB2. No mutations were identified in EGFR, whereas one tumor had an insertion mutation in exon 20 of ERBB2. Both amplification and protein overexpression of EGFR occur in serous ovarian carcinoma, but EGFR copy number has a stronger prognostic value. This makes EGFR amplification a potentially useful criterion for selecting patients in clinical trials testing the effect of EGFR inhibitors in serous ovarian carcinoma.

Topoisomerase II-alpha expression increases with increasing Gleason score and with hormone insensitivity in prostate carcinoma

AIM

To investigate and compare topoisomerase II-alpha expression in benign prostatic hyperplasia (BPH), prostate cancer of varying Gleason scores and hormone-insensitive prostate cancer.

METHODS

The immunohistochemical expression of topoisomerase II-alpha antibody in the above-mentioned diagnostic categories was investigated and compared.

RESULTS

Increased expression of topoisomerase II-alpha was seen in the prostate cancers of Gleason scores 7 and 8-10 (p = 0.000) compared with prostate cancers of Gleason score 6 and BPH (p = 0.245). Statistically significant differences were found in the topoisomerase II-alpha gene expression between prostate cancers categorised by Gleason Score. Also, increased expression of topoisomerase II-alpha was seen in the known hormone-resistant prostate carcinomas compared with prostate cancers with no hormone treatment in the subgroup with Gleason scores 8-10, which approached statistical significance (p = 0.081). No statistically significant difference was observed in topoisomerase II-alpha expression between the groups with BPH and prostate carcinoma of Gleason score 6 (p = 0.245).

CONCLUSION

Topoisomerase II-alpha expression was found to increase with the known prognostic marker Gleason score and with hormone insensitivity. Objective evidence is provided for clinical trials with drugs targeting topoisomerase II-alpha to be targeted to patients with prostate cancers of Gleason Score >6 and, in particular, prostate cancers of Gleason Scores 8-10.

Prognostic, predictive and therapeutic implications of HER2 in invasive epithelial ovarian cancer

The HER2 oncogene encodes a transmembrane protein partially homologous to epidermal growth factor receptor. This oncogene has been studied mainly in breast cancer where it has prognostic, predictive and therapeutic target value. The expression of HER2 in epithelial ovarian cancer has been less studied. HER2 expression can be determined through IHC, FISH, CISH and ELISA among other tests, with reported positivity frequencies of overexpression varying from 1.8% to 76%. In some studies HER2 overexpression has been associated with advanced stages, poorly differentiated tumors, resistance to chemotherapy and shortened survival. Although trastuzumab is able to produce a low response rate as a single agent in pretreated ovarian cancer patients with overexpression of HER2, its usefulness is limited due to the low frequency of strong expression. To date there is not enough bases for assessment and HER2-based therapies in epithelial ovarian cancer.

Antibody Immunity to the p53 Oncogenic Protein Is a Prognostic Indicator in Ovarian Cancer

Purpose

Presence of intratumoral T-cell infiltration has been linked to improved survival in ovarian cancer patients. We questioned whether antibody immunity specific for ovarian cancer tumor antigens would predict disease outcome. We evaluated humoral immune responses against ovarian cancer antigens p53, HER-2/neu, and topoisomerase IIα.

Patients and Methods

Serum was collected from 104 women (median age, 59 years; range, 34 to 89 years) at the time of their initial definitive surgery for ovarian cancer. Serum was analyzed by enzyme-linked immunosorbent assay for antibodies to p53, HER-2/neu, and topoisomerase IIα proteins. Antibody immunity to tetanus toxoid was assessed as a control. The incidence of humoral immunity at the time of diagnosis to any of these three antigens was tabulated. For patients with advanced-stage disease (III/IV), correlation was made between the presence of tumor-specific immunity at the time of diagnosis and overall survival. Patients were followed for a median of 1.8 years.

Results

Multivariate analysis showed the presence of p53 antibodies to be an independent variable for prediction of overall survival in advanced-stage patients. Overall survival was significantly higher for patients with antibodies to p53 when compared with patients without p53 antibodies (P = .01). The median survival for p53 antibody-positive patients was 51 months (95% CI, 23.5 to 60.5 months) compared with 24 months (95% CI, 19.4 to 28.6 months) for patients without antibodies to p53.

Conclusion

Data presented here demonstrate that advanced stage ovarian cancer patients can have detectable tumor-specific antibody immunity and that immunity to p53 may predict improved overall survival in patients with advanced-stage disease.

Advances in real-time PCR: application to clinical laboratory diagnostics

The polymerase chain reaction (PCR) has become one of the most important tools in molecular diagnostics, providing exquisite sensitivity and specificity for detection of nucleic acid targets. Real-time monitoring of PCR has simplified and accelerated PCR laboratory procedures and has increased information obtained from specimens including routine quantification and differentiation of amplification products. Clinical diagnostic applications and uses of real-time PCR are growing exponentially, real-time PCR is rapidly replacing traditional PCR, and new diagnostic uses likely will emerge. This review analyzes the scope of present and potential future clinical diagnostic applications of this powerful technique. Critical discussions focus on basic concepts, variations, data analysis, instrument platforms, signal detection formats, sample collection, assay design, and execution of real-time PCR.

Assessment of Her-1, Her-2, And Her-3 expression and Her-2 amplification in advanced stage ovarian carcinoma

The human epidermal growth factor receptor (Her) family of receptor tyrosine kinases includes Her-1, Her-2, and Her-3. The overexpression of Her-1 and Her-2 have been reported previously in surface epithelial ovarian cancer. Although up to one-third of ovarian carcinomas have been found to have amplification or overexpression of Her-2, responses to trastuzumab therapy in these patients have been disappointing. In this study, we examined Her-1, Her-2, and Her- 3 protein expression as well as the frequency of Her-2 amplification in a series of 103 high-grade, advanced-stage (FIGO stage III or IV) ovarian surface epithelial carcinomas. Immunohistochemical staining using commercially available antibodies against Her-1-3 and fluorescence in situ hybridization (FISH) using probes against Her-2 and chromosome 17 centromere (CEP) were performed on a tissue microarray containing cores of tumor from 103 surface epithelial carcinomas (85 serous, 6 mixed surface epithelial, 5 clear cell, 3 endometrioid, 3 undifferentiated, 1 mucinous). Nine of 99 (9.1%) tumors were positive for Her-1 expression and 5 of 102 (4.9%) tumors were positive for Her-2 expression, with 1 showing strong immunoreactivity. None of the Her-1 positive tumors exhibited Her-2 immunoreactivity. There was no correlation between Her-1 or Her-2 expression and survival. Using Her-2:centromere fluorescence ratios of 2.0 or 1.5 as cutoffs in assessment of Her-2 amplification, 8 of 75 (10.7%) and 25 of 75 (33.3%) tumors, respectively, showed Her-2 amplification. Two of eight tumors that showed higher level (>2) Her-2 amplification by FISH also were positive for Her-2 by immunohistochemistry. Only 3 of 103 tumors expressed Her-3. Immunoreactivity for Her-1 and Her-2 was less frequently observed in this series than has been previously reported. The strong correlation between Her-2 immunostaining and amplification characteristic of breast carcinoma is not seen in ovarian carcinoma. These results indicated that few patients with ovarian carcinoma have tumors that would benefit from therapy targeted specifically against Her-1, Her-2, or Her-3.

Determination of HER2/neu status in uterine serous papillary carcinoma: Comparative analysis of immunohistochemistry and fluorescence in situ hybridization

OBJECTIVE

To evaluate and compare HER2/neu protein overexpression and gene amplification in uterine serous papillary endometrial cancer (USPC).

STUDY DESIGN

Immunohistochemical (IHC) and fluorescent in situ hybridization (FISH) assays were used to analyze and compare HER2/neu protein expression and gene amplification, respectively, in paraffin blocks from 26 women harboring stage IA to IV USPC treated at the University of Arkansas for Medical Sciences from 1997 to 2004. Chromosome 17 polysomy status by FISH was also assessed in all specimens.

RESULTS

Moderate-to-strong expression of HER2/neu protein was noted in 16 (62%) of 26 USPC samples evaluated, with 7 (27%) samples showing moderate staining (2+) and 9 (35%) showing strong staining (3+) for HER2/neu. Amplification of the ERBB2 gene by FISH was observed in 11 of the 26 (42%) cases. Protein overexpression and gene amplification were found to correlate in 100% (9 of 9) of the 3+ positive tumors and 2 out of 7 (29%) of the 2+ positive tumors. Heterogeneity was noted in 3 cases in the amplification of the HER2/neu gene within the same tumor samples with pockets of amplified tumor cells amidst nonamplified tumor cells. None of the 10 USPC cases scored by IHC as 0 or 1+ was found positive for ERBB2 amplification by FISH.

CONCLUSIONS

Amplification of the HER2/neu oncogene represents a common finding in USPC. FISH analysis should be used for confirmation of gene amplification in USPC showing 2+ expression of HER2/neu. Prior screening and selection of appropriate immunohistochemistry-positive areas may be beneficial in the selection of some USPC patients undergoing FISH analysis.