Lewis and related tumor-associated determinants on ovarian carcinoma

Tumor-associated glycans and their role in gynecological cancers: accelerating translational research by novel high-throughput approaches

Glycans are important partners in many biological processes, including carcinogenesis. The rapidly developing field of functional glycomics becomes one of the frontiers of biology and biomedicine. Aberrant glycosylation of proteins and lipids occurs commonly during malignant transformation and leads to the expression of specific tumor-associated glycans. The appearance of aberrant glycans on carcinoma cells is typically associated with grade, invasion, metastasis and overall poor prognosis. Cancer-associated carbohydrates are mostly located on the surface of cancer cells and are therefore potential diagnostic biomarkers. Currently, there is increasing interest in cancer-associated aberrant glycosylation, with growing numbers of characteristic cancer targets being detected every day. Breast and ovarian cancer are the most common and lethal malignancies in women, respectively, and potential glycan biomarkers hold promise for early detection and targeted therapies. However, the acceleration of research and comprehensive multi-target investigation of cancer-specific glycans could only be successfully achieved with the help of a combination of novel high-throughput glycomic approaches.

What are the current best immunohistochemical markers for the diagnosis of epithelioid mesothelioma? A review and update

Numerous immunohistochemical markers that can assist in the diagnosis of epithelioid mesotheliomas, some of which have only recently been recognized, are currently available. Because the various types of carcinomas express these markers differently, their selection for inclusion in a diagnostic panel can vary according to the differential diagnosis. This article provides a critical review of all of the information that is presently available on those markers that are believed to have the greatest potential for assisting in distinguishing between epithelioid mesotheliomas and those carcinomas with which they are most likely to be confused. Information is also provided regarding the panels of immunohistochemical markers that are, at present, recommended in these differential diagnoses.

Flow cytometric immunophenotyping of cancer cells in effusion specimens: Diagnostic and research applications

Flow cytometry (FCM) immunophenotyping is frequently used as an ancillary technique for the diagnosis of hematological malignancies or for measurement of DNA content. In recent years, we applied FCM to the diagnosis of metastatic adenocarcinoma and malignant mesothelioma in effusions. We established a panel of antibodies that allows for rapid and effective differentiation between epithelial cells, mesothelial cells, and leukocytes. FCM was subsequently used for quantitative analysis of integrin subunits. Recently, we studied different parameters of the immune response, including HLA molecules and chemokine receptors, using this method. Our data suggest that FCM is an effective method for the characterization of cancer cells in clinical effusion specimens in both the diagnostic and research setting, and that this method is comparable to immunohistochemistry in terms of sensitivity and specificity, with the additional advantage of providing quantitative data. This review discusses previous work in this area and the future potential of this method in the characterization of tumor cells in serous effusions.

Monocyte/macrophage and T-cell infiltrates in peritoneum of patients with ovarian cancer or benign pelvic disease

Background

We previously showed that tumor-free peritoneum of patients with epithelial ovarian cancer (EOC) exhibited enhanced expression of several inflammatory response genes compared to peritoneum of benign disease. Here, we examined peritoneal inflammatory cell patterns to determine their concordance with selected enhanced genes.

Methods

Expression patterns of selected inflammatory genes were mined from our previously published data base. Bilateral pelvic peritoneal and subjacent stromal specimens were obtained from 20 women with EOC and 7 women with benign pelvic conditions. Sections were first stained by indirect immunoperoxidase and numbers of monocytes/macrophages (MO/MA), T cells, B cells, and NK cells counted. Proportions of CD68+ cells and CD3+ cells that coexpressed MO/MA differentiation factors (CD163, CCR1, CXCR8, VCAM1, and phosphorylated cytosolic phospholipase A₂ [pcPLA₂]), which had demonstrated expression in EOC peritoneal samples, were determined by multicolor immunofluorescence.

Results

MO/MA were present on both sides of the pelvic peritoneum in EOC patients, with infiltration of the subjacent stroma and mesothelium. CD68+ MO/MA, the most commonly represented population, and CD3+ T cells were present more often in EOC than in benign pelvic tumors. NK cells, B cells, and granulocytes were rare. CXCL8 (IL-8) and the chemokine receptor CCR1 were coexpressed more frequently on MO/MA than on CD3+ cells contrasting with CD68+/CD163+ cells that coexpressed CXCL8 less often. An important activated enzyme in the eicosanoid pathway, pcPLA₂, was highly expressed on both CD68+ and CD163+ cells. The adherence molecule Vascular Cell Adhesion Molecule-1 (VCAM1) was expressed on CD31+ endothelial cells and on a proportion of CD68+ MO/MA but rarely on CD3+ cells.

Conclusion

The pelvic peritoneum in EOC exhibits a general pattern of chronic inflammation, represented primarily by differentiated MO/MA, and distinct from that in benign conditions concordant with previous profiling results.

Value of immunohistochemistry in distinguishing peritoneal mesothelioma from serous carcinoma of the ovary and peritoneum: a review and update

At present, a large number of immunohistochemical markers that can be used in the differential diagnosis between epithelioid peritoneal mesotheliomas and serous carcinomas are available. However, great differences of opinion exist regarding the individual value of some of these markers. This article provides a critical review of all of the information that is currently available on those markers that have the greatest potential for assisting in distinguishing between peritoneal mesotheliomas and serous carcinomas. The conclusion of this review indicates that the positive serous carcinoma markers, by and large, have a higher degree of sensitivity and specificity in assisting in discriminating between these malignancies than the positive mesothelioma markers. From a practical point of view, a combination of MOC-31 (or Ber-EP4), estrogen receptors, and calretinin immunostaining should allow a clear distinction to be made between epithelioid peritoneal mesotheliomas and serous carcinomas in most cases.

The diagnostic utility of immunohistochemistry and electron microscopy in distinguishing between peritoneal mesotheliomas and serous carcinomas: a comparative study

The histologic distinction between peritoneal epithelioid mesotheliomas and serous carcinomas diffusely involving the peritoneum may be difficult, but it can be facilitated by the use of immunohistochemistry and electron microscopy. D2-40 and podoplanin are two recently recognized lymphatic endothelial markers that can be expressed in normal mesothelial cells and mesotheliomas. The purpose of this study is to compare the value of these new mesothelial markers with those that are commonly used for discriminating between mesotheliomas and serous carcinomas, and also to determine the current role of electron microscopy in distinguishing between these malignancies. A total of 40 peritoneal epithelioid mesotheliomas and 45 serous carcinomas of the ovary (15 primary, 30 metastatic to the peritoneum) were investigated for the expression of the following markers: D2-40, podoplanin, calretinin, keratin 5/6, thrombomodulin, MOC-31, Ber-EP4, B72.3 (TAG-72), BG-8 (Lewis(Y)), CA19-9, and leu-M1 (CD15). All 40 (100%) of the mesotheliomas reacted for calretinin, 93% for D2-40, 93% for podoplanin, 93% for keratin 5/6, 73% for thrombomodulin, 13% for Ber-EP4, 5% for MOC-31, 3% for BG-8, and none for B72.3, CA19-9, or leu-M1. All 45 (100%) serous carcinomas were positive for Ber-EP4, 98% for MOC-31, 73% for B72.3, 73% for BG-8, 67% for CA19-9, 58% for leu-M1, 31% for keratin 5/6, 31% for calretinin, 13% for D2-40, 13% for podoplanin, and 4% for thrombomodulin. After analyzing the results, it is concluded that Ber-EP4 and MOC-31 are the best negative mesothelioma markers for differentiating between epithelioid mesotheliomas and serous carcinomas. The best discriminators among the positive markers for mesotheliomas are D2-40, podoplanin, and calretinin. From a practical point of view, Ber-EP4 and MOC-31, in combination with calretinin, and/or D2-40 or podoplanin allow the differential diagnosis to be established between mesothelioma and serous carcinoma in nearly all instances. As a clear distinction could be made between these two malignancies in all of the cases in which electron microscopy was performed, this technique can be very useful in establishing the correct diagnosis when the immunohistochemical results are equivocal or further support of a diagnosis of either mesothelioma or serous carcinoma is needed.

The immunohistochemical diagnosis of mesothelioma: a comparative study of epithelioid mesothelioma and lung adenocarcinoma

A large number of immunohistochemical markers that can facilitate the distinction between epithelioid pleural mesotheliomas and pulmonary peripheral adenocarcinomas have recently become available. The aim of this study is to compare the value of these new markers with others that are already commonly used for this purpose and to determine which are, at present, the best for discriminating between these malignancies. Sixty epithelioid mesotheliomas and 50 lung adenocarcinomas were investigated for expression of the following markers: calretinin, cytokeratin 5/6, WT1, thrombomodulin, mesothelin, CD44S, HBME-1, N-cadherin, E-cadherin, MOC-31, thyroid transcription factor-1 (TTF-1), BG-8 (Lewisy), carcinoembryonic antigen (CEA), Ber-EP4, B72.3 (TAG-72), leu-M1 (CD15), CA19-9, epithelial membrane antigen (EMA), and vimentin. All (100%) of the mesotheliomas reacted for calretinin, cytokeratin 5/6, and mesothelin, 93% for WT1, 93% for EMA, 85% for HBME-1, 77% for thrombomodulin; 73% for CD44S, 73% for N-cadherin, 55% for vimentin, 40% for E-cadherin, 18% for Ber-EP4, 8% for MOC-31, 7% for BG-8, and none for CEA, B72.3, leu-M1, TTF-1, or CA19-9. Of the adenocarcinomas, 100% were positive for MOC-31, Ber-EP4, and EMA, 96% for BG-8, 88% for CEA, 88% for E-cadherin, 84% for B72.3, 74% for TTF-1, 72% for leu-M1, 68% for HBME-1, 48% for CD44S, 48% for CA19-9, 38% for mesothelin, 38% for vimentin, 30% for N-cadherin, 14% for thrombomodulin, 8% for calretinin, 2% for cytokeratin 5/6, and none for WT1. After analyzing the results, it is concluded that calretinin, cytokeratin 5/6, and WT1 are the best positive markers for differentiating epithelioid malignant mesothelioma from pulmonary adenocarcinoma. The best discriminators among the antibodies considered to be negative markers for mesothelioma are CEA, MOC-31, Ber-EP4, BG-8, and B72.3. A panel of four markers (two positive and two negative) selected based upon availability and which ones yield good staining results in a given laboratory is recommended. Because of their specificity and sensitivity for mesotheliomas, the best combination appears to be calretinin and cytokeratin 5/6 (or WT1) for the positive markers and CEA and MOC-31 (or B72.3, Ber-EP4, or BG-8) for the negative markers. An extensive and detailed review of the literature is also provided.

Immunohistochemical diagnosis of epithelioid mesotheliomas: a critical review of old markers, new markers

Numerous new immunohistochemical markers that can be used in the diagnosis of mesothelioma have recently become available. As a result, new panels of antibodies that could be useful for distinguishing between epithelioid mesotheliomas and adenocarcinomas have been proposed. However, great differences of opinion exist regarding the individual value of some of these markers, especially when compared with those whose value has already been established. This article provides a critical review of the currently available information on those markers that could be useful in the diagnosis of epithelioid mesotheliomas or whose utility remains controversial. A practical approach to the diagnosis of these tumors is also provided.

Expression of carbohydrate antigens in advanced-stage ovarian carcinomas and their metastases-A clinicopathologic study

OBJECTIVE

Up-regulated expression or loss of expression of various carbohydrate antigens on the surface of cancer cells has been associated with a metastatic phenotype and poor survival in epithelial malignancies of different origins. The object of this study was to investigate the expression of carbohydrate antigens in two groups of patients diagnosed with advanced-stage ovarian carcinoma-one with an extremely favorable outcome and the other with a uniformly poor survival.

METHODS

Sections from 76 paraffin-embedded blocks (primary ovarian carcinomas and metastatic lesions) from 45 patients diagnosed with advanced-stage ovarian carcinomas (FIGO stages III-IV) were immunohistochemically stained using five monoclonal antibodies for Lewis(y) (Le(y))(two antibodies), Sialyl Lewis(x) (Slex), Tn, and Sialyl Tn (STn) antigens. Patients were divided in two groups based on outcome. Long-term survivors (21 patients) and short-term survivors (24 patients) were defined using a double cut-off of 36 months for disease-free survival (DFS) and 60 months for overall survival (OS). Staining results for primary tumors and metastases were analyzed separately.

RESULTS

Mean follow-up period was 70 months. The mean values for DFS and OS were 109 and 125 months for long-term survivors and 3 and 25 months for short-term survivors. Staining for all four antigens was seen in the majority of cases (range = 72-96%) and tended to be comparable in primary tumors and their metastases. However, absence of immunoreactivity for STn was seen in 9/38 (24%) metastatic lesions and only 1/38 (3%) primary tumors. This finding did not reach statistical significance (P > 0.05). A combined pattern of membranous and cytoplasmic staining was predominant in the majority of cases. Enhanced staining for Le(y) and STn was detected in the invasive front of some tumors, while Slex and Tn immunoreactivity did not relate to cell location. Primary tumors and metastatic lesions of long-term survivors displayed immunoreactivity patterns that were comparable to those of short-term survivors. In the evaluation of survival curves, more diffuse staining for Slex showed marginal correlation with poor survival (P = 0.05), while a trend toward poorer survival was seen in tumors that were more extensively stained for Le(y) and Tn (P > 0.05).

CONCLUSIONS

Le(y), Slex, STn, and Tn antigens are widely expressed in primary ovarian carcinomas and their metastases. Altered expression of Sialyl Tn is observed with tumor progression in a fraction of ovarian carcinomas. Expression of membrane carbohydrate residues is prevalent in tumors of both long-term and short-term survivors and does not appear to be a strong predictor of disease outcome. However, larger studies are needed to further elucidate the role of these molecules in ovarian carcinogenesis.

Selection of carbohydrate antigens in human epithelial ovarian cancers as targets for immunotherapy: serous and mucinous tumors exhibit distinctive patterns of expression

Expression of blood group-related carbohydrate antigens was examined in frozen sections from a series of ovarian carcinomas of different histological types using an indirect immunoperoxidase technique. Antigenic specificities belonging to the O(H) and Lewis blood group families (H-1, H-2, Le(a), sLe(a), Le(x), sLe(x), Le(b) and Le(y)) or the mucin-core family (Tn, sTn and TF) were studied. A distinct difference in antigen expression between mucinous and other ovarian carcinomas (serous and endometrioid) was observed. Specifically, mucinous tumors tended to express sTn, Le(a) and sLe(a) strongly and homogeneously, whereas serous and endometrioid tumors rarely expressed these specificities and, in contrast, expressed Le(y) and H type 2 antigen strongly. When expressed in serous tumors, sTn was usually distributed in a heterogeneous pattern, whereas sTn expression in mucinous tumors was much more homogeneous. The distribution of Le(y) in serous tumors was noticeably homogeneous. H-1, Le(x), sLe(x), Le(b), TF and Tn specificities were rarely expressed in any type of ovarian carcinoma. Our results provide further support for the different histogenesis of mucinous and non-mucinous tumors and indicate alternative differentiation pathways for the 3 pathological subtypes of ovarian tumor. They also provide the basis for the choice of carbohydrate antigens for active and passive immunotherapy of ovarian carcinomas.

Role of immunohistochemistry in distinguishing epithelial peritoneal mesotheliomas from peritoneal and ovarian serous carcinomas

The histologic distinction between epithelial peritoneal mesothelioma and papillary serous carcinoma diffusely involving the peritoneum may be difficult. Although some investigators have indicated that immunohistochemistry can facilitate this differential diagnosis. only a few studies using a limited number of markers have been published. In this study, the immunoreactivity of keratin 5/6, vimentin, epithelial membrane antigen, thrombomodulin, calretinin, MOC-31, Ber-EP4, carcinoembryonic antigen, TAG-72 (B72.3), CD15 (Leu-M1), placental alkaline phosphatase, CA19-9, CA-125, HBME-1, 44-3A6, and S-100 protein was investigated in 35 epithelial peritoneal mesotheliomas, and 45 papillary serous carcinomas [30 ovarian (10 primary and 20 metastatic to the peritoneum) and 15 papillary serous carcinomas of the peritoneum]. After analyzing the results, it is concluded that calretinin, thrombomodulin, and keratin 5/6 are the best positive markers for differentiating epithelial malignant mesotheliomas from papillary serous carcinomas diffusely involving the peritoneum. The best diagnostic discriminators among the antibodies considered to be negative markers for mesothelioma are MOC-31, B72.3, Ber-EP4, CA19-9, and Leu-M1. Immunostaining for carcinoembryonic antigen, placental alkaline phosphatase, epithelial membrane antigen, vimentin, HBME-1, 44-3A6, CA-125, or S-100 have little or no diagnostic utility in establishing the differential diagnosis between these conditions. The results of this study also confirm previous observations indicating that both papillary serous carcinomas of the peritoneum and serous carcinomas of the ovary have a similar phenotype and, therefore, immunohistochemical studies are not useful in separating these entities.

Altered expression of Lewis blood group and related antigens in fetal, normal adult and malignant tissues of the uterine endometrium

The expression of the Lewis blood group and its related antigens in fetal, normal adult and malignant tissues of the uterine endometrium was examined immunohistochemically using a panel of mouse monoclonal antibodies with specificities for Lewis-a (La), Sialyl Lewis-a (SLa), Lewis-b (Lb), Lewis-X (LX), Sialyl Lewis-X (SLX) and Lewis-Y (LY) antigens. La, SLa and SLX having one fucose residue were detected in a small number of fetal tissues, while Lb and LY having two fucose residues were found in most cases. In the adult endometrium, expression of Lb and LY was considerably lower than those in fetal tissues, although expression of La and SLa was not different between these two tissues. Expression of LX and SLX was pronounced in adult when compared with fetal tissues. Malignant endometrial glands expressed La, SLa, Lb and LY, extensively, while LX and SLX were expressed less than in normal tissues. Lb and LY can thus be considered oncofetal antigens, extensively expressed in fetal and malignant tissues but not in normal adult tissues. Expression of Lb and LY was greater than that of La and SLA in carcinoma; an increase in the activity of fucose transferase might be associated with malignant transformation in the uterine endometrium.

Biochemical characterization of glycoprotein components in human ovarian cyst fluids by lectins

1. Perchloric acid-soluble glycoprotein fractions (PASFs) were separated, in yields of 180-610 mg per 100 ml of cyst fluid, from the cyst fluids of human ovarian cystadenomas (OCAs) in benign and borderline and ovarian clear cell carcinoma (OCC) in malignant, and then identified as glycoproteins with 19.1-69.5% carbohydrate by their chemical composition analyses. 2. These PASFs reacted with anti-A, -B, -Lea and/or -Leb sera, but did not react with anti-H, -M and -N sera. All of the PASFs reacted with Ricinus communis lectin (RCA-I). Among these PASFs, PASFs from the cyst fluids of OCA in benign did not react with Arachis hypogaea anti-T lectin (PNA) and both of the anti-N lectins of Vicia graminea (VGA) and Vicia unijuga (VUA), and PASFs from OCA in borderline reacted with only PNA and PASFs from OCC in malignant reacted with the three lectins, PNA, VGA and VUA. However, none of PASFs from human normal sera and various normal organ tissues reacted with any of RCA, PNA, VGA and VUA. 3. The above-mentioned results seem to show that the examination of glycoproteins of ovarian cyst fluids by the combined use of RCA-I, PNA and VGA (or VUA) permits biochemical diagnosis of the canceration degree of ovarian cystomas.

Observer variation in histologic classification of malignant and borderline ovarian tumors

Eight hundred sixty-nine primary malignant or borderline ovarian tumors reported to the Norwegian Cancer Registry were reviewed. The histologic slides were randomly distributed to six observers and classified according to the World Health Organization classification of ovarian tumors. By rotation of slides, each tumor was successively reviewed by three observers. Each observer was given approximately 40 duplicates of slides he or she had typed before, mixed in with the slides for the third review. A contracted version of the classification with 27 entries was used in the analysis. Mean intraobserver reproducibility was 62% (kappa, 0.53), varying from 50% to 75% (kappa, 0.34 to 0.70) for the individual observers. The mean rate of agreement between two observers was 56% (kappa, 0.46), varying from 46% to 65% for the individual pairs of observers. The rate of full agreement among three observers was 41%. The most common disagreements were between different specific types of carcinoma, between undifferentiated and differentiated carcinoma, between borderline and malignant tumors, between unclassified and classified carcinoma, and between mixed and pure types of carcinoma. Very low reproducibility was obtained for mixed and unclassified carcinoma.