Prognostic Marker In Ovarian Cancer Research Articles

Human Kallikrein 8 Protein Is a Favorable Prognostic Marker in Ovarian Cancer

Human Kallikrein 8 Protein Is a Favorable Prognostic Marker in Ovarian Cancer

Human Kallikrein 8 Protease Confers a Favorable Clinical Outcome in Non–Small Cell Lung Cancer by Suppressing Tumor Cell Invasiveness

The human kallikrein 8 (KLK8) gene, a member of the human tissue kallikrein gene family, encodes a serine protease. The KLK8 protein (hK8) is known to be a favorable prognostic marker in ovarian cancer, but the biological basis of this is not understood. We found that overexpressing the KLK8 gene in highly invasive lung cancer cell lines suppresses their invasiveness. This role in invasiveness was further confirmed by the fact that inhibition of endogenous KLK8 expression with a specific short hairpin RNA reduced cancer cell invasiveness. In situ degradation and cell adhesion assays showed that proteins produced from KLK8 splice variants modify the extracellular microenvironment by cleaving fibronectin. DNA microarray experiments and staining of cells for actin filaments revealed that the degradation of fibronectin by hK8 suppresses integrin signaling and retards cancer cell motility by inhibiting actin polymerization. In addition, studies in a mouse model coupled with the detection of circulating tumor cells by quantitative PCR for the human Alu sequence showed that KLK8 suppresses tumor growth and invasion in vivo. Finally, studies of clinical specimens from patients with non-small cell lung cancer showed that the time to postoperative recurrence was longer for early-stage patients (stages I and II) with high KLK8 expression (mean, 49.9 months) than for patients with low KLK8 expression (mean, 22.9 months). Collectively, these findings show that KLK8 expression confers a favorable clinical outcome in non-small cell lung cancer by suppressing tumor cell invasiveness.

Gene expression profiling of human ovarian tumours

There is currently a lack of reliable diagnostic and prognostic markers for ovarian cancer. We established gene expression profiles for 120 human ovarian tumours to identify determinants of histologic subtype, grade and degree of malignancy. Unsupervised cluster analysis of the most variable set of expression data resulted in three major tumour groups. One consisted predominantly of benign tumours, one contained mostly malignant tumours, and one was comprised of a mixture of borderline and malignant tumours. Using two supervised approaches, we identified a set of genes that distinguished the benign, borderline and malignant phenotypes. These algorithms were unable to establish profiles for histologic subtype or grade. To validate these findings, the expression of 21 candidate genes selected from these analyses was measured by quantitative RT–PCR using an independent set of tumour samples. Hierarchical clustering of these data resulted in two major groups, one benign and one malignant, with the borderline tumours interspersed between the two groups. These results indicate that borderline ovarian tumours may be classified as either benign or malignant, and that this classifier could be useful for predicting the clinical course of borderline tumours. Immunohistochemical analysis also demonstrated increased expression of CD24 antigen in malignant versus benign tumour tissue. The data that we have generated will contribute to a growing body of expression data that more accurately define the biologic and clinical characteristics of ovarian cancers.

Analysis of Gene Amplification and Prognostic Markers in Ovarian Cancer Using Comparative Genomic Hybridization for Microarrays and Immunohistochemical Analysis for Tissue Microarrays

To identify oncogene amplification involved in ovarian carcinogenesis, we studied 21 ovarian carcinomas and 5 serous borderline tumors using conventional comparative genomic hybridization (CGH) and CGH to a genomic DNA microarray. Immunohistochemical analysis of the proteins encoded by the genes that were amplified frequently (FGF3/4, FGFR1, CCNE1, PAK1, JUNB, and MDM2) was performed on a tissue microarray comprising 254 cases of ovarian neoplasms. Regarding histologic type, characteristic patterns of copy number changes were revealed. They correlated with histologic tumor type and with intratumoral heterogeneity. Gain of FGF3/4 and CCNE1 was found in all serous carcinomas. Endometrioid carcinomas most frequently showed gain of JUNB (83%), KRAS2 (67%), MYCN (50%), ESR (50%), and CCND2 (50%). Of the serous borderline tumors, 80% harbored amplification of FGFR1 and MDM2 and a 75% gain of PIK3CA. Only CCNE1 immunoreactivity was significantly correlated with CGH results (P < .05) and postoperative survival (P < .05). Microarray-based genomic analysis in combination with immunohistochemical analysis was found to be a powerful technique for identification of clinically relevant gene amplification in human ovarian cancer.

Human Kallikrein 8 Protein Is a Favorable Prognostic Marker in Ovarian Cancer

Human kallikrein 8 (hK8/neuropsin/ovasin; encoded by KLK8) is a steroid hormone-regulated secreted serine protease differentially expressed in ovarian carcinoma. KLK8 mRNA levels are associated with a favorable patient prognosis and hK8 protein levels are elevated in the sera of 62% ovarian cancer patients, suggesting that KLK8/hK8 is a prospective biomarker. Given the above, the aim of the present study was to determine if tissue hK8 bears any prognostic significance in ovarian cancer. Using a newly developed ELISA, hK8 was quantified in 136 ovarian tumor extracts and correlated with clinicopathologic variables and outcome [progression-free survival (PFS); overall survival (OS)] over a median follow-up period of 42 months. hK8 levels in ovarian tumor cytosols ranged from 0 to 478 ng/mg total protein, with a median of 30 ng/mg. An optimal cutoff value of 25.8 ng/mg total protein (74th percentile) was selected based on the ability of hK8 values to predict the PFS of the study population and to categorize tumors as hK8 positive or negative. Women with hK8-positive tumors most often had lower-grade tumors (G1), no residual tumor after surgery, and optimal debulking success (P < 0.05). Univariate and multivariate analyses revealed that patients with hK8-positive tumors had a significantly longer PFS and OS than hK8-negative patients (P < 0.05). Kaplan-Meier survival curves further confirmed a reduced risk of relapse and death in women with hK8-positive tumors (P = 0.001 and P = 0.014, respectively). These results indicate that hK8 is an independent marker of favorable prognosis in ovarian cancer.

Molecular prognostic markers in ovarian cancer: toward patient-tailored therapy

In ovarian cancer the ceiling seems to be reached with chemotherapeutic drugs. Therefore a paradigm shift is needed. Instead of treating all patients according to standard guidelines, individualized molecular targeted treatment should be aimed for. This means that molecular profiles of the distinct ovarian cancer subtypes should be established. Until recently, most studies trying to identify molecular targets were single-marker studies. The prognostic role of key components of apoptotic and prosurvival pathways such as p53, EGFR, and HER2 has been extensively studied because resistance to chemotherapy is often caused by failure of tumor cells to go into apoptosis. However, it is more than likely that different ovarian cancer subtypes with extensive molecular heterogeneity exist. Therefore, exploration of the potential of specific tumor-targeted therapy, based on expression of a prognostic tumor profile, may be of interest. Recently, new profiling techniques, such as DNA and protein microarrays, have enabled high-throughput screening of tumors. In this review an overview of the current status of prognostic marker and molecular targeting research in ovarian cancer, including microarray studies, is presented.

Molecular prognostic markers in ovarian cancer: toward patient-tailored therapy

In ovarian cancer the ceiling seems to be reached with chemotherapeutic drugs. Therefore a paradigm shift is needed. Instead of treating all patients according to standard guidelines, individualized molecular targeted treatment should be aimed for. This means that molecular profiles of the distinct ovarian cancer subtypes should be established. Until recently, most studies trying to identify molecular targets were single-marker studies. The prognostic role of key components of apoptotic and prosurvival pathways such as p53, EGFR, and HER2 has been extensively studied because resistance to chemotherapy is often caused by failure of tumor cells to go into apoptosis. However, it is more than likely that different ovarian cancer subtypes with extensive molecular heterogeneity exist. Therefore, exploration of the potential of specific tumor-targeted therapy, based on expression of a prognostic tumor profile, may be of interest. Recently, new profiling techniques, such as DNA and protein microarrays, have enabled high-throughput screening of tumors. In this review an overview of the current status of prognostic marker and molecular targeting research in ovarian cancer, including microarray studies, is presented.

Hypermethylation of 18S and 28S Ribosomal DNAs Predicts Progression-Free Survival in Patients with Ovarian Cancer

Repetitive ribosomal DNA (rDNA) genes are GC-rich clusters in the human genome. The aim of the study was to determine the methylation status of two rDNA subunits, the 18S and 28S genes, in ovarian tumors and to correlate methylation levels with clinicopathologic features in a cohort of ovarian cancer patients. 18S and 28S rDNA methylation was examined by quantitative methylation-specific PCR in 74 late-stage ovarian cancers, 9 histologically uninvolved, and 11 normal ovarian surface epithelial samples. In addition, methylation and gene expression levels of 18S and 28S rDNAs in two ovarian cancer cell lines were examined by reverse transcription-PCR before and after treatment with the demethylating drug 5'-aza-2'-deoxycytidine. The methylation level (amount of methylated rDNA/beta-actin) of 18S and 28S rDNAs was significantly higher (P < 0.05) in tumors than in normal ovarian surface epithelial samples. Methylation of 18S and 28S rDNA was highly correlated (R2= 0.842). Multivariate analysis by Cox regression found that rDNA hypermethylation [hazard ratio (HR), 0.25; P < 0.01], but not age (HR, 1.29; P = 0.291) and stage (HR, 1.09; P = 0.709), was independently associated with longer progression-free survival. In ovarian cancer cell lines, methylation levels of rDNA correlated with gene down-regulation and 5'-aza-2'-deoxycytidine treatment resulted in a moderate increase in 18S and 28S rDNA gene expressions. This is the first report of rDNA hypermethylation in ovarian tumors. Furthermore, rDNA methylation levels were higher in patients with long progression-free survival versus patients with short survival. Thus, rDNA methylation as a prognostic marker in ovarian cancer warrants further investigation.

Plasma Bikunin As a Favorable Prognostic Factor in Ovarian Cancer

Bikunin is a multifunctional glycoprotein, which mediates suppression of tumor cell invasion and metastasis. The measurement of bikunin levels in the tissue of patients with malignant diseases has been introduced as a new and simple diagnostic tool for the evaluation of prognosis. The high bikunin expression in ovarian cancer tissue would enable the use of soluble bikunin protein present in the circulation of ovarian cancer patients as a biomarker of disease. We developed a double-antibody immunoassay for bikunin and detected its presence in normal human circulation. We quantified, by enzyme-linked immunosorbent assay and/or immunoblot assay bikunin in sera from 200 healthy women (controls), 200 patients with benign gynecologic diseases, and 327 patients with ovarian cancer before surgical removal of the tumor. When the values of bikunin corresponding to the median were used as the cutoff value (11.5 microg/mL), low plasma bikunin was strongly associated with late-stage, suboptimal debulking with large residual tumor (> 2 cm) and low response to chemotherapy. The median survival time of the patients with a high bikunin level was more than 60 months as compared with 26 months among those with low bikunin level (P = .002). This difference corresponded to a 2.2-fold increased risk of dying for the lower plasma bikunin patients (hazard ratio, 0.45; P = .023) and remained significant in multivariate analysis (hazard ratio, 0.63; P = .041). Preoperative plasma bikunin concentration is a strong and independent favorable prognostic marker for ovarian cancer.

Expression of progesterone receptor is a favorable prognostic marker in ovarian cancer

Objective Receptors for estrogen (ER), progesterone (PR), or androgen (AR) are predictive and prognostic markers of malignancy of multiple endocrine organs, including endometrial and breast cancer. However, the role of ERs, PRs, or ARs in the carcinogenesis of ovarian cancer, another sex hormone-dependent malignancy, is still controversial despite numerous studies that have attempted to determine their role. The disagreement in the findings may result from the fact that the numbers of tumor samples in studies have been small and that different immunohistochemical methods have been used that can introduce variation in the scoring of the histology. We therefore examined the pattern of expression of ERs, PRs, and ARs in a large number of samples of primary ovarian carcinoma by using a tissue microarray technique. Methods We constructed a tissue microarray with 322 samples of primary ovarian carcinoma obtained at surgery performed at The University of Texas M. D. Anderson Cancer Center between 1990 and 2000. Immunohistochemistry studies were performed by using the immunoperoxidase technique against primary antibodies (ER, PR, and AR). Results ERs, PRs, and ARs were differently expressed in different histotypes of ovarian cancer: ERs were expressed in 77.3% of all cases but more highly expressed in serous and endometrioid types; PRs were expressed in 26.2% of all cases but most highly expressed in the endometrioid type < 64.2%; and ARs were expressed in 43.7% of all cases but were most highly expressed in serous (47.5%) carcinomas. Of particular importance, the expression of PRs, but not ERs or ARs, was associated with better survival ( P < 0.0001) in univariate and multivariate analyses. Conclusions The PR is an independent marker, with its overexpression associated with a favorable prognosis in women with ovarian cancer.

Amplicon profiling reveals cytoplasmic overexpression of MUC1 protein as an indicator of resistance to platinum-based chemotherapy in patients with ovarian cancer

Chromosomal gains of 1q21-q22 and 13q12-q14 were closely related with the chemoresistance of patients with ovarian cancer in our previous CGH (comparative genomic hybridization) study. We conducted the present study to determine the amplified genes on chromosome 1q. Comparisons of relative copy numbers of clinically platinum-sensitive ovarian tumors (CR-group, n=14) and platinum-resistant tumors (PD-group, n=14) were carried out using real-time PCR from ten different gene loci on chromosome 1q. Increased copy numbers were frequently observed in PD-group tumors, especially in the region between WI-8123 and MUC1. Relative copy number of MUC1 over 1.5 was observed in 13 (92%) of 14 PD-group tumors and 3 (21%) of 14 CR-group tumors (p<0.05). Moreover, cytoplasmic expressions of MUC1 protein were significantly higher in PD-group than those in CR-group (p<0.01). We concluded that the cytoplasmic overexpression of MUC1 might be an indicator of resistance to platinum-based chemotherapy and a prognostic marker in ovarian cancer.

Kallikrein 4 is associated with paclitaxel resistance in ovarian cancer

Objective. Carcinoma of the ovary is the most fatal malignancy of the female genital tract in western countries. The effectiveness of chemotherapy is limited by the acquisition of drug resistance. Several members of the kallikrein ( KLK) family were recently shown to be expressed in ovarian cancer and implicated in disease prognosis. One of these is KLK4, whose increased mRNA expression was identified as a poor prognostic marker in ovarian cancer. The goal of this study was to investigate if KLK4 protein (hK4) is expressed in ovarian carcinoma lesions and if it is associated with paclitaxel resistance. Methods. Immunohistochemistry was used to assess hK4 expression. The 126 lesions were from a cohort of 46 patients with platinum-resistant tumors, which were treated with weekly paclitaxel for recurrent disease. The overall response rate to weekly paclitaxel was 52% (24 of 46) and for patients with tumors resistant to standard three weekly paclitaxel treatment 48% (16 of 33). Results. Immunohistochemistry indicated that 85% (79 of 93) of lesions from paclitaxel-resistant patients expressed hK4, while only 61% (20 of 33) of lesions were positive for hK4 from paclitaxel sensitive patients. Statistical analysis showed that the intensity of hK4 staining was significantly associated with paclitaxel resistance ( P = 0.005), whereas hK4 staining extent showed marginal significance ( P = 0.05), but was significantly correlated with higher histological grade ( P < 0.001). Conclusion. These data show that hK4 is expressed in ovarian cancer and suggest that hK4 expression might be a predictive marker for paclitaxel resistance.

Critical evaluation of p53 as a prognostic marker in ovarian cancer.

The tumour suppressor gene encoding p53 has been shown from experimental studies to have a crucial role in how cells respond to DNA damage. p53 has important functions in apoptosis, cell-cycle arrest and DNA repair, largely mediated by its activity on gene transcription. However, despite this wealth of in vitro data, its role in how tumours respond to DNA damage induced by chemotherapeutic drugs remains controversial. In this review, we highlight some of the problems surrounding design and analysis of studies of p53 as a prognostic marker of clinical outcome, using ovarian cancer as an example. We aim to build on the knowledge of the published literature in ovarian cancer to identify criteria for clinical studies that should give a more definitive estimate of the role of p53 in clinical drug resistance. A search of three public databases using keywords combined with Boolean operators identified 64 clinical publications investigating the relationship of p53 to clinical outcome following chemotherapy in ovarian cancer. Although 43% of 215 published analyses from the 64 papers reported a significant correlation between p53 status and a clinical endpoint relevant to chemoresistance, only six analyses fulfil minimum criteria and none of these finds a statistically significant correlation of p53 with chemotherapy-resistance endpoints. The results from published clinical studies suggest a more complex role of p53 mutation in the mechanism of resistance in ovarian cancer than is suggested by in vitro studies.

Oviductal glycoprotein, a new differentiation-based indicator present in early ovarian epithelial neoplasia and cortical inclusion cysts

Objective. With neoplastic progression, the precursor of epithelial ovarian cancers, the ovarian surface epithelium (OSE), undergoes Mullerian differentiation, usually of the oviductal type. The aim of this study was to examine the expression of oviduct-specific glycoprotein (OGP), a marker of normal oviductal epithelium, for use as a diagnostic or prognostic marker for ovarian cancer. Methods and materials. Immunohistochemical analysis for OGP was performed on 389 ovarian tumors and 19 normal ovaries, as well as 433 cases representing 45 normal tissues and 51 benign and malignant tumor types from 37 different tissues. Results. OGP was absent in OSE but present in 28 of 31 epithelial inclusion cysts, 13 of 14 (93%) serous cystadenomas, and 46 of 65 (71%) serous borderline tumors. Of 183 serous adenocarcinomas, 26 (14%) were positive for OGP, including 5 of 8 (63%) grade I, 7 of 41 (17%) grade II, and 14 of 134 (10%) grade III carcinomas. OGP was found in 7 of 14 (50%) borderline and 9 of 15 (60%) malignant mucinous ovarian tumors and in 10 of 39 (26%) endometrioid adenocarcinomas. The localization of OGP in the lumen of glandular structures suggested that it was secreted. OGP was absent in 41 of 45 normal tissues and positive in oviduct and, weakly, in salivary gland, duodenum, and ileum. Forty-six types of nongynecologic tumors were negative, as were gynecologic neoplasms except for 2 of 47 cervical and 3 of 56 endometrial carcinomas. Conclusion. OGP is a new tubal differentiation marker which characterizes benign and borderline serous neoplasms and may indicate early events in ovarian carcinogenesis.

TNF-α Up-regulated the Expression of HuR, a Prognostic Marker for Ovarian Cancer and Hu Syndrome, in BJAB Cells

Background: Hu syndrome, a neurological disorder, is characterized by the remote effect of small cell lung cancer on the neural degeneration. The suspicious effectors for this disease are anti-Hu autoantibodies or Hu-related CD8+ T lymphocytes. Interestingly, the same effectors have been suggested to act against tumor growth and this phenomenon may represent natural tumor immunity. For these diagnostic and therapeutic reasons, the demand for antibodies against Hu protein is rapidly growing. Methods: Polyclonal and monoclonal antibodies were generated using recombinant HuR protein. Western blot analyses were performed to check the specificity of generated antibodies using various recombinant proteins and cell lysates. Extracellular stimuli for HuR expression had been searched and HuR-associated proteins were isolated from polysome lysates and then separated in a 2-dimensional gel. Results: Polyclonal and monoclonal antibodies against HuR protein were generated and these antibodies showed HuR specificity. Antibodies were also useful to detect and immunoprecipitate endogenous HuR protein in Jurkat and BJAB. This report also revealed that TNF-ǯ treatment in BJAB up-regulated HuR expression. Lastly, protein profile in HuR-associated mRNAprotein complexes was mapped by 2-dimensional gel electrophoresis. Conclusion: This study reported that new antibodies against HuR protein were successfully generated. Currently, project to develop a diagnostic kit is in process. Also, this report showed that TNF-ǯ up-regulated HuR expression in BJAB and protein profile associated with HuR protein was mapped. (Immune Network 2004;4(3):184-189)

Steroid hormone regulation and prognostic value of the human kallikrein gene 14 in ovarian cancer.

To study KLK14 gene expression in endocrine-related cancers, we studied its hormonal regulation in breast and ovarian cancer cell lines. Our kinetic and blocking experiments suggest that this up-regulation is mediated through the androgen receptor. We then studied the expression of KLK14 by quantitative reverse transcriptase-polymerase chain reaction in 155 consecutive ovarian tumors and correlated these findings with clinicopathologic parameters, response to chemotherapy, and survival. A stepwise reduction was observed in the levels of KLK14 messenger RNA in normal, benign, and cancerous tissues (P < .001). Expression levels were significantly higher in patients with early stage disease and optimal debulking and in patients who responded to chemotherapy. Kaplan-Meier survival curves demonstrated longer progression-free and overall survival in patients with KLK14-positive tumors than in patients with KLK14-negative tumors (P < .001). When all other prognostic variables were controlled in the multivariate analysis, KLK14 retained its prognostic significance (progression-free and overall survival, respectively, hazard ratios, 0.43 and 0.53; P = .027 and .014). A weak negative correlation was found between KLK14 expression and serum CA-125. KLK14 is a new, independent, and favorable prognostic marker for ovarian cancer.

Steroid Hormone Regulation and Prognostic Value of the Human Kallikrein Gene 14 in Ovarian Cancer

To study KLK14 gene expression in endocrine-related cancers, we studied its hormonal regulation in breast and ovarian cancer cell lines. Our kinetic and blocking experiments suggest that this up-regulation is mediated through the androgen receptor. We then studied the expression of KLK14 by quantitative reverse transcriptase–polymerase chain reaction in 155 consecutive ovarian tumors and correlated these findings with clinicopathologic parameters, response to chemotherapy, and survival. A stepwise reduction was observed in the levels of KLK14 messenger RNA in normal, benign, and cancerous tissues (P < .001). Expression levels were significantly higher in patients with early stage disease and optimal debulking and in patients who responded to chemotherapy. Kaplan-Meier survival curves demonstrated longer progression-free and overall survival in patients with KLK14-positive tumors than in patients with KLK14-negative tumors (P < .001). When all other prognostic variables were controlled in the multivariate analysis, KLK14 retained its prognostic significance (progression-free and overall survival, respectively, hazard ratios, 0.43 and 0.53; P = .027 and .014). A weak negative correlation was found between KLK14 expression and serum CA-125. KLK14 is a new, independent, and favorable prognostic marker for ovarian cancer.

Tumor-reactive immunoglobulins in ovarian cancer: diagnostic and therapeutic significance? (review).

Inhibition of the immune system has been observed in association with most stages of ovarian cancer; however, the mechanisms involved in the induction and maintenance of this chronic immune unresponsiveness associated with cancer progression are poorly understood. This immunosuppressed state is primarily defined as the failure to eradicate the tumor. This immunosuppressed state is generally associated with decreased numbers and reactivity of lymphoid cells in women with ovarian cancer. The degree of immune dysfunction in ovarian cancer patients has been demonstrated to correlate with patient survival. While ovarian cancer patients generally fail to exhibit effective immunosurveillance, as manifested by continued tumor growth and progression, the presence of tumor-reactive immunoglobulins can be demonstrated in these women, indicating the continued presence of immune recognition. We have not only demonstrated the presence of tumor-reactive antibodies in ovarian cancer patients, but have also shown that the levels of these antibodies increase as the disease progresses. The antigens recognized by the patients' humoral response have been identified as either membrane-associated or intra-cellular. In general, the localization of these antigens tend to be linked to the patient's prognosis. The presence of a humoral response against intracellular proteins are correlated with poor prognosis, while autoantibodies reactive with surface components appear to have a better prognosis. In addition to general antigen recognition, these reactive antibodies have been utilized to define specific epitopes on tumor-associated proteins. Certain specific antigenic epitopes exhibit common recognition among patients with the same tumor type. The specific recognition of certain epitopes can provide early evidence of aberrant protein expression and this aberrant expression of certain proteins, such as procathepsin D, appear to be linked to the tumor's acquisition of specific malignant characteristics, including metastasis formation and chemoresistance. Despite the existence of circulating tumor-reactive immunoglobulins, their presence correlates, in general, with poor prognosis and poor host survival. Since tumor-reactive immunoglobulins are elicited and can be detected early in the development of tumors and their enhanced synthesis is induced prior to the clinical manifestation of recurrence, the assessment of the tumor-reactive immune response against specific antigenic epitopes should represent an early significant diagnostic and prognostic marker in ovarian cancer.

Elevated serum levels of a c-erbB-2 oncogene product in ovarian cancer patients and in pregnancy.

Amplification of the proto-oncogene c-erbB-2 (HER-2/neu) has been shown to be a prognostic marker in ovarian cancer. In order to obtain further information on the biological role of the c-erbB-2 gene product p185 it is necessary to quantify expression levels. In this study we evaluated an enzyme-linked immunosorbent assay (ELISA) for the extracellular domain of p185 to determine whether a soluble oncoprotein fragment can be detected in the serum of ovarian cancer patients and in the serum of pregnant women. Sera from 199 women (57 previously untreated ovarian cancer patients, 62 pregnant women and 80 healthy controls) were assayed in a sandwich ELISA utilizing two mouse monoclonal antibodies. To study c-erbB-2 overexpression in ovarian cancer tissue samples we have used an immunohistochemical technique involving a monoclonal antibody specifically reactive with the external domain of the protein p185. The mean serum value for the normal controls was 1203 HNU/ml with a standard deviation (SD) of 279 HNU/ml and a range of 595-1947 HNU/ml. We chose a level of 1761 HNU/ml (2 SD above the mean) as a cut-off to distinguish individuals with elevated levels. The ovarian cancer patients' serum values ranged from 526 to 16,332 HNU/ml. Immunohistochemically detectable p185 was noted in 8 of 57 ovarian cancer patients. The oncoprotein fragment levels in the sera from these 8 patients ranged from 878 to 16,332 HNU/ml. Of 8 patients with p185 overexpression in their tumors, 4 had elevated serum levels. In the sera from the 49 cancer patients without overexpression the values were distributed in the range 526-2892 HNU/ml. There was no association between serum oncoprotein fragment levels and tumor stage, histological type or grading. Serum concentrations of the p185 fragment in pregnancy ranged from 612 to 3265 HNU/ml. The highest levels were found in the third trimester. The results of the present study raise the possibility that the soluble c-erbB-2 protein level in serum is an indicator for cell proliferation and therefore deserves further evaluation as a diagnostic tool in ovarian cancer patients and pregnancy.

Pre-operative plasma tetranectin as a prognostic marker in ovarian cancer patients.

Plasma tetranectin (TN) was tested as a biochemical prognostic marker in ovarian cancer on 39 patients. In stage I + II the 5-year survival was 33% (2/6) if plasma TN was < or = 6.7 mg l-1 and 100% (15/15) with plasma TN > 6.7 mg l-1. For stage III + IV the survival was 0% (0/11) at 26 months for patients with plasma TN < or = 6.7 mg l-1 and 29% (2/7) after 5 years with plasma TN > 6.7 mg l-1. By multivariate testing the relative hazard (RH) of death was found to be 73 times higher in patients with plasma TN < or = 6.7 mg l-1 compared to patients with values above 6.7 mg l-1 (p < 0.001). For comparison, the maximal RH for the other tested variables were: 15 for advanced stage, 2.5 for grade, four for residual tumour and 2.5 for younger age.