Nucleolar immunofluorescence in human hematological malignancies.

Rabbit antibodies to the nuclear Tris extract of HeLa cells which have been shown by the indirect immunofluorescence technique to localize in nucleoli of a variety of human malignant tumors but not in a number of nontumor tissues also produced bright fluorescence in nucleoli of tumor cells in several hematological malignancies. The tumors studied included Hodgkins malignant lymphoma, non-Hodgkins malignant lymphoma, acute myeloid and acute myelomonocytic leukemia, chronic lymphatic and chronic myeloid leukemia. In contrast, none of the corresponding normal cell lines in the bone marrow exhibited bright nucleolar fluorescence. In addition, neither the cells of patients with acute infectious mononucleosis nor lymphoid hyperplasia exhibited bright nucleolar fluorescence. These studies suggest that antibodies to HeLa cell nucleolar antigens may be useful in immunodiagnosis of human malignancies.     

Proliferating cell nuclear antigen (PCNA) and human malignant tumor nucleolar antigens (HMTNA) in nucleoli of human hematological malignancies

Lymphoma (Lymphocytic non-Hodgkin's malignant lymphoma) and leukemic (chronic lymphocytic, acute and chronic myeloid, myelomonocytic leukemia) cells were studied by indirect immunofluorescence to evaluate the presence of proliferating cell nuclear antigen (PCNA) and human malignant tumor nuclear antigen (HMTNA) in their nucleoli. Most cells in lymph node smears of lymphocytic non-Hodgkin's malignant lymphoma (NHML) developed a bright nucleolar fluorescence with HMTNA antibodies. PCNA was detected in nucleoli of a limited number of cells which apparently represent the proliferating cell population in these lymphomas. Similarly, in the bone marrow smears of patients with chronic lymphocytic leukemia most cells possessed a nucleolar fluorescence for HMTNA and PCNA was present in nucleoli of a limited number of cells. In the bone marrow smears of patients with myeloid or myelomonocytic leukemias most blastic or monocytoid cells also developed a bright nucleolar fluorescence with HMTNA antibodies and PCNA was present only in a small percentage of these cells. Leukemic cells with PCNA in their nucleoli like thekhuntigen might represent a proliferating cell population in late G1-early S phase.     

Different nucleolar antigen expression in resting and proliferating human lymphocytes as studied by fluorescence microscopy and flow cytometry

Abstract. The aim of this study was to investigate the use of a nucleolar antigen to discriminate between proliferating and resting cells. Antinucleolar antibodies (Si87) were obtained from a scleroderma patient. The specificity of immunostaining was verified and morphological changes in nucleoli were monitored using a fluorescence microscope. Fluorescence of propidium iodide-stained DNA and nucleolar immunofluorescence were measured by flow cytometry.
Following phytohaemagglutinin stimulation the number of nucleoli of normal human peripheral blood lymphocytes increased about 3-fold, accompanied by enlargement of nucleolar size. Simultaneously a mean increase in total immunofluorescence per cell by a factor of three was detected. The method developed and applied here allows a discrimination between resting and proliferating human lumphocytes on the basis of their nucleolar antigen content.     

Different nucleolar antigen expression in resting and proliferating human lymphocytes as studied by fluorescence microscopy and flow cytometry

The aim of this study was to investigate the use of a nucleolar antigen to discriminate between proliferating and resting cells. Antinucleolar antibodies (Si87) were obtained from a scleroderma patient. The specificity of immunostaining was verified and morphological changes in nucleoli were monitored using a fluorescence microscope. Fluorescence of propidium iodide-stained DNA and nucleolar immunofluorescence were measured by flow cytometry. Following phytohaemagglutinin stimulation the number of nucleoli of normal human peripheral blood lymphocytes increased about 3-fold, accompanied by enlargement of nucleolar size. Simultaneously a mean increase in total immunofluorescence per cell by a factor of three was detected. The method developed and applied here allows a discrimination between resting and proliferating human lymphocytes on the basis of their nucleolar antigen content.     

Automated analysis of rat breast tumors. Comparison of four methods

Chemically-induced malignant rat breast tumors pose diagnostic dilemmas since the majority are well-differentiated, noninvasive papillary lesions that are barely distinguishable from benign papillary lesions. This study compared several automated modalities to see which best separated benign from malignant breast tumors. Thirty-three carcinogen-induced rat breast tumors (13 adenomas, 10 papillary carcinomas and 10 invasive carcinomas) were evaluated by static (image) cytometry (ICM) of integrated optical density, by flow cytometry (FCM) and by two automated morphometric protocols, contextual analysis and single-gland analysis. DNA ploidy analysis, by either ICM or FCM, did not discriminate between the benign and malignant tumors. Contextual analysis correctly identified 11 of 13 benign and 17 of 20 malignant lesions (P less than .01). Single-gland analysis correctly identified all 13 benign and 17 of 20 malignant lesions (P less than .01). No method distinguished invasive from noninvasive carcinomas. The data suggest that architectural features are more important than nuclear features in differentiating benign from malignant rat breast tumors.     

Characterization of a monoclonal antibody, OVB1, which binds to a unique determinant in human ovarian carcinomas and myeloid cells

A monoclonal antibody, OVB1, was generated against a human ovarian carcinoma cell line, OVCAR-3. The antigen reacting with this antibody was strongly expressed on the external surface of the plasma membrane of OVCAR-3 cells and cells of 4/4 other ovarian carcinoma lines. Variable density and homogeneity of expression was found on cells from 5/5 breast carcinoma lines. Various ovarian tumor specimens and normal human tissues were frozen, cryostat-sectioned, and examined for OVB1 reactivity using immunoperoxidase methods. A strong, uniform, homogeneous reaction on 10/10 ovarian carcinoma specimens and variable, non-homogeneous reactions on breast tumors were seen. Normal tissues reacting with the antibody include thyroid, pituitary pars intermedia, breast ductal epithelium, Auerbach's plexus and neuronal processes in the GI tract, colonic mucosal epithelium, and salivary gland ductal epithelium. Polymorphonuclear leukocytes, eosinophils, and approximately 13% of peripheral lymphocytes, as well as cells around germinal centers in lymph nodes and spleen, showed strong reactivity by immunofluorescence and/or immunoperoxidase. Expression of the OVB1 antigen in the myeloid cells of normal human bone marrow occurred from the promyelocyte stage through to more mature cells in a subpopulation of myeloblasts. Indirect immunofluorescence of live peripheral blood cells showed localization to the surface of PMNs, eosinophils, and certain lymphocytes. Double-immunofluorescence studies (with a direct fluorescein-anti-lactoferrin antibody conjugate) showed co-localization of OVB1 and OKM1 (anti-C3bi receptor) antibodies to specific granules of PMNs. Localization of OVB1 and OKM1 antibodies to granular structures in the PMN was confirmed by electron microscopy using the ferritin bridge technique. The antigen reacting with the OVB1 antibody was shown to be neuraminidase sensitive, but protease insensitive. The OVB1 monoclonal antibody may be useful in identification of ovarian tumors and subclassification of myeloid leukemias.     

Correlation between AgNOR count and subjective AgNOR pattern assessment score in cytology and histology of breast lumps.

OBJECTIVE: To find the correlation of argyrophilic nucleolar organizer region (AgNOR) count and subjective AgNOR pattern assessment (SAPA) score in cytology and histology of breast lumps. STUDY DESIGN: The study group consisted of 73 patients (46 malignant, 27 benign) with breast lumps. In all cases, fine needle aspiration cytology (FNAC) samples and histologic specimens were studied by conventional and silver staining for AgNORs. RESULTS: AgNOR count and SAPA score were helpful in differentiating benign from malignant tumors in both the cytologic smear and histologic specimen. AgNOR count was 6.94+/-2.74 in FNAC and 6.57+/-2.73 in histology of malignant tumors, while in benign tumors it was 2.75+/-0.74 in FNAC and 2.68+/-0.77 in histology. SAPA score was 9.02+/-4.60 in FNAC and 8.76+/-2.34 in histology in malignant tumors and 5.87+/-0.93 in FNAC and 5.82+/- 0.83 in histology in benign tumors. CONCLUSION: Both AgNOR count and SAPA score gave similar results, but SAPA score is a more convenient, reproducible and rapid method of AgNOR evaluation.     

Secretory component in differentiating normal epithelium, benign lesions and malignancy in the human breast as monitored by monoclonal antibodies

An immunohistochemical study of the expression of the secretory component (SC) in human mammary gland epithelium at various stages of differentiation, as well as in benign and malignant breast tumours, was undertaken using three mouse monoclonal antibodies. Antibody RICEO-SC-05 (SC-05), raised against a partially purified preparation of human SC, and reacting with a reduction-resistant epitope present in both free and polymeric immunoglobulin-bound SC, was compared in immunoperoxidase and immunofluorescence studies on a diverse range of normal tissues, to 2 reference anti-SC antibodies (LICR-LONLC28 and RICEO-MFG-12). All three antibodies reacted with secretory epithelia only, consistent with known patterns of expression of SC in tissues, although there was an unexpected reaction by all anti-SC antibodies with some Hassal's corpuscles of the thymus. Staining patterns seen in the normal resting, pregnant, lactating and regressing (after weaning) breast provide evidence for differentiation-associated changes in the production of SC, and support the concept of terminal ductal lobular units (TDLUs) as functional compartments of the mammary gland. SC was detected in all but one benign breast lesion (n = 53) as compared to only 24% positive cases with heterogeneous expression of SC found among 176 primary and metastatic breast carcinomas examined. In a series of 40 primary breast carcinomas and their corresponding lymph node metastases, a good overall correlation was found between the expression of SC in the matched specimens; aside from 3 heterogeneously SC-positive carcinomas whose metastatic counterparts were SC-negative. Our results demonstrate a potential application for monoclonal antibodies to SC in the study of human mammary gland differentiation, but suggest that the value of an assay for SC in the diagnosis of breast carcinomas is questionable due to the generally low expression of SC by either primary or metastatic breast lesions.     

Monoclonal antibodies to antigens abnormally expressed in breast cancer

We report the production, screening, and characterization of ten murine monoclonal antibodies directed at antigens that are expressed abnormally in human breast tumors. Immunoperoxidase staining of frozen and fixed tissues shows the antigens to be present at low levels on the luminal membrane of normal breast cells and at high levels in the cytoplasm and surface membrane of breast tumor cells. The ten antibodies appear to recognize six different epitopes on the basis of their quantitative differences in reactivity against four antigen preparations, as measured by ELISA. Immunoblots show that eight of the ten antibodies recognize a 300,000 MW molecule from breast tumor preparations; six of these antibodies also react with a second molecule from the same tumor preparations of 280,000 MW. Seven antibodies react with an antigen from milk fat globule membrane of 330,000 MW. It therefore appears that the two molecules from tumor tissue and the one molecule from normal tissue share common epitopes. Selected antibodies were tested for reactivity against 25 primary breast tumors and 14 pairs of primary and metastatic breast tumors. Three antibodies have broad reactivity and stain more than 80% of primary tumors; the three other antibodies identify subsets of those tumors. Results of staining pairs of primary and metastatic lesions show that metastases continue to express antigens of the primary lesion in a high percentage of cells.     

Flow cytometric analysis of DNA content and keratins by using CK7, CK8, CK18, CK19, and KL1 monoclonal antibodies in benign and malignant human breast tumors.

We have used a double-labelling flow cytometry analysis of keratin (CK) and DNA in breast cancer. Five monoclonal anti-keratin antibodies were tested: KL1 recognizing Mr 55,000-57,000 keratins, and "anti-glandular epithelia," LE41, RGE-53, and LP2K specific for CK n. 7, 8, 18, and 19 of Moll's classification, respectively. Flow cytometric (DNA-CK) analysis was performed on 10 benign and 19 malignant human breast tumors. All the benign tumors were diploid and 63% of the malignant tumors were aneuploid. This technique permits the analysis of DNA in the epithelial fraction alone. In aneuploid tumors, gating the DNA-keratin-positive population allowed accurate DNA analysis without interference due to debris background and non-epithelial cells. Moreover, double-labelling using the CK19 antibody gave a better identification of near-diploid tumors. An enhancement of keratin expression in malignant tumors was observed with CK 19 (P less than 0.001), KL1 (P less than 0.01), CK 8 (P less than 0.05), and CK18 (n.s.) compared to benign tumors. The comparison of keratin expression in aneuploid and diploid malignant tumors revealed reduced CK8, CK18, and CK19 in the former.     

Human tumor and normal tissue reactivity of the anti-(breast cancer) monoclonal antibody BA-Br-3 and its similarity to the anti-(epithelial membrane antigen) monoclonal antibody E29

Summary A mouse monoclonal antibody (BA-Br-3) raised against the breast carcinoma cell line CAMA-1 was previously shown to react with a 300-kDa globule-like glycoprotein from human milk fat also expressed in the cytoplasm and on the surface of human carcinoma cells of different histological types. In this report the reactivity of this mAb with a large number of normal and malignant human tissues was analyzed using immunoperoxidase techniques. When tested on sections of both fresh-frozen tissues and formalin-fixed, paraffin-embedded tissues, BA-Br-3 reacted with a formalin-resistant antigenic determinant expressed by normal and malignant epithelial cells. Preferential reactivity was observed at the apical portion of ductal epithelial cells in normal breast and in glandular epithelia distributed in several other organs. Reactivity with mucin-like secretions in the lumina of ducts was also found. BA-Br-3 reacted mostly in heterogenous staining patterns with 88% of 49 breast carcinoma specimens tested, regardless of their histological type or whether they were primary or secondary neoplasms. Testing of epithelial malignant tumors other than breast carcinomas with this antibody showed that 127 of 151 (84%) were also reactive. mAb BA-Br-3 and E29 (a commercially available anti-(epithelial membrane antigen) shared very similar staining patterns and distributions of reactivity with breast and other epithelial tumors. However, BA-Br-3 showed a significantly higher percentage of reactivity with melanoma (33% versus 6%,P = 0.003) and a trend toward a higher percentage of reactivity with sarcoma (55% versus 27%,P >0.05). This antibody, therefore, defines a molecule that is a member of the mucin-like epithelial membrane antigen family. Further studies are warranted to determine its usefulness in antibody-directed cancer diagnosis, prognosis, and immunotherapy.     

The synthesis of a proteinase inhibitor, α-1-antichymotrypsin,by human breast epithelial cells

The synthesis and release of glycoproteins were studied in organ cultures of human breast surgical specimens and in established breast epithelial cell lines, MCF-7 and MDA-MB-231. Biosynthesis was monitored by the incorporation of ¹⁴C-glucosamine. Labeled macromolecules in the culture supernatants were analyzed by biochemical and immunological techniques. One to 8% of the labeled glycoproteins from benign breast and infiltrating ductal carcinoma specimens was precipitated by antibodies produced against human serum 7α-1-antichymotrypsin. Twelve percent of the total glycoproteins from the culture supernatants of the MCF-7 cell line was identified as α-1-antichymo-trypsin. Both the normal serum and the human breast epithelia-derived proteinase inhibitor can be resolved into similar subclasses by two-dimensional gel electrophoresis. MDA-MB-231 and MCF-7 cells which were extensively washed with EDTA, serum-free medium, and phosphate-buffered saline retain this proteinase inhibitor on their cell surfaces. Three to 4% of the total cell-surface iodinated components was immunoprecipitated by these specific antibodies. Since α-1-antichymotrypsin is a potent inhibitor of neutral proteinases such as cathepsin G, the demonstration of its synthesis by benign and malignant breast epithelial cells is of considerable interest. This glycoprotein may represent the epithelia's own protective shield of cell surface components and the cell's attempt to moderate the effects of invading leukocytes. In addition, it may play a regulatory role in the maintenance of three-dimensional glandular structures.     

Silver-binding nucleoli and nucleolar organizer regions in fine needle aspiration cytology of the breast

Silver staining was used to demonstrate nucleoli and nucleolar organizer regions (NORs) in cytopreparations from breast fine needle aspiration (FNA) biopsies, with the resulting black dots being a combination of silver-binding nucleoli and dispersed NORs. Discrete black dots in 200 nuclei were manually counted in 25 silver-stained biopsies; the cytologic diagnoses were made on routine Papanicolaou-stained cytopreparations from the same aspirates. Although malignant breast lesions showed higher counts than did benign breast disease, an overlap of one malignant and three benign lesions occurred. Therefore, the method cannot be recommended for reliably discriminating between malignant and benign routine breast specimens obtained by FNA; it may have some value in assessing tumor behavior.     

Levels of O6-methylguanine acceptor protein in extracts of human breast tumor tissues.

We have measured the abilities of extracts of tissues from human breast tumors to demethylate adducts of O6-meG in exogenous DNA by transfer of the methyl group to an acceptor protein. The results have shown that all 21 specimens examined (including 5 non-neoplastic, 11 malignant tumors and 5 benign growth) contained significant amounts of O6-meG acceptor activity, removing on average 221.1 +/- 2.1 (SEM) fmol O6-meG per mg protein or 10.07 +/- 0.98 (SEM) fmol O6-megG per microgram DNA in the extracts. There were also wide interindividual variations, which were not age-dependent, and there were no significant differences between the non-neoplastic and neoplastic tissues obtained from individuals with benign or with malignant disease. It was estimated that the average number of O6-meG acceptor molecules per cell in normal human breast tissues was calculated as 46,000 +/- 7000 (SEM).     

上皮生长因子受体和癌胚抗原分子内血型Y配基表达的免疫生化分析

以抗CEA、EGF-γ和血型前体Y配基抗原的单抗进行分析,结果表明:结肠癌组织中表达CEA和血型前体Y配基较强,而EGF-γ表达水平极低;进一步鉴定分析,识别血型前体Y配基抗原决定簇的单抗C_(14)与肿瘤具有较好的反应性。并发现这种决定簇存在于各种生物大分子中,包括以糖蛋白和糖脂形式存在,并表达于EGF-γ与CEA分子中。这一结果提示血型前体抗原过量表达于肿瘤细胞中,不但是血型组织相容抗原,可能也参与到一些特殊生物分子中,应深入研究和鉴定其功能。     

Expression of genes coding for pS2, c-erbB2, estrogen receptor and the H23 breast tumor-associated antigen. A comparative analysis in breast cancer

Expression of the gene coding for a new breast tumor-associated antigen, H23, was compared to expression of genes coding for pS2, c-erbB2 and estrogen receptor (ER). Comparison involved mRNA expression in normal and malignant breast tissues as well as in non-breast tumors. Results obtained by RNA dot blot and Northern hybridizations showed that expression of the H23 antigen coding gene is a discriminatory marker in human breast cancer. It is expressed in 92% of breast tumors whereas 69%, 62% and 56% of breast tumors demonstrate significant mRNA levels of c-erbB2, ER and pS2, respectively. Non-malignant or normal breast tissue expresses much lower levels of the H23 antigen mRNA. From the comparative analysis presented here it is concluded that the gene coding for H23 antigen furnishes a most useful marker for human breast cancer.     

Characterization of nucleolar organizers in carcinomatous mammmary lesions

An argyrophil stain for nucleolar organizer regions (NORs) has been applied to paraffin sections of 24 malignant and 3 benign breast tumors. It was found that the total number of Ag-NORs in malignant breast lesions (3.66) significantly exceeded those in benign lesions (1.65). Relationship between this index and some clinical parameters was studied. A positive correlation between NORs and histological grading and prognostic was found.     

Validation of new aromatase monoclonal antibodies for immunohistochemistry: progress report

Intratumoral aromatase is a potential therapeutic target for the treatment of postmenopausal estrogen-dependent breast cancers. Therefore, reliable methods should be developed for routine application for the detection of intratumoral aromatase. A multi-center collaborative group has been established to generate and validate new aromatase monoclonal antibodies (MAbs). A recombinant GST–aromatase fusion protein was expressed in baculovirus and the purified protein was used for immunization of mice either as a native or formalin-fixed antigen. Hybridomas were generated using standard techniques and screened biochemically prior to immunohistochemistry (IHC) evaluation in human placenta, ovary and breast cancer tissues. Twenty-three MAbs selected by biochemical assays were further evaluated by IHC of paraffin-embedded tissue sections including normal ovary, and placenta, and a small series of 10 breast carcinomas. Of the 23 MAbs, 2 (clones 677 and F2) were determined to specifically stain cell types known to express aromatase in normal tissues. In breast carcinomas staining of malignant epithelium, adipose tissue, normal/benign and stromal compartments was detected. IHC was performed and independently evaluated by three pathologists (HS, TJA and SGS), each using the same evaluation criteria for staining intensity and proportion of immunopositive cells. With these two MAbs, interpathologist and intralaboratory variations were minimal in comparison with differences which could be detected between tissue specimens and antibodies.     

Estrogen receptor mutations in breast cancer

The malignant potential of solid tumors is related to the ability to invade adjacent tissue and to metastasize. These properties of cancer cells depend on the synthesis of proteolytic enzymes which are able to digest adjacent connective tissue and basement membranes. We hypothesized that all elements of the plasminogen activation system might be overexpressed in malignant human breast tumors, functioning as an essential element in tumor invasion and metastasis. As determined by histopathological methods, the malignant tumors showed statistically significantly higher expression of urokinase plasminogen activator (uPA), type-1 plasminogen activator inhibitor (PAI-1), and especially urokinase plasminogen activator receptor (uPAR) than benign tissues. All those elements were present in higher amounts in the cancer cells than in the cells of benign or normal breast tissues. High exhibition of tissue plasminogen activator (tPA) found in cancer seems to be random and not related to the malignant or benign state, since benign and malignant tumors show overexpression of tissue plasminogen activator with similar frequency. When the tumors express high amounts of uPA, they express a high amount of uPAR in 50% of cases and PAI-1 in 57.3% of cases. When urokinase is expressed in low amount, the receptor is low in 28.6% and inhibitor in 21.4% of malignant breast tumors. This statistically significant consensus, 78.6% in the case of urokinase and its receptor and 78.6% in case of urokinase and its inhibitor, suggests that these activities may be the result of a unique mechanism of control, activated in the last steps of malignant transformation.     

Classification of breast lesions based on a dual S-shaped logistic model in dynamic contrast enhanced magnetic resonance imaging

This study proposes a novel dual S-shaped logistic model for automatically quantifying the characteristic kinetic curves of breast lesions and for distinguishing malignant from benign breast tumors on dynamic contrast enhanced (DCE) magnetic resonance (MR) images. D(α,β) is the diagnostic parameter derived from the logistic model. Significant differences were found in D(α,β) between the malignant benign groups. Fisher's Linear Discriminant analysis correctly classified more than 90% of the benign and malignant kinetic breast data using the derived diagnostic parameter (D(α,β)). Receiver operating characteristic curve analysis of the derived diagnostic parameter (D(α,β)) indicated high sensitivity and specificity to differentiate malignancy from benignancy. The dual S-shaped logistic model was effectively used to fit the kinetic curves of breast lesions in DCE-MR. Separation between benign and malignant breast lesions was achieved with sufficient accuracy by using the derived diagnostic parameter D(α,β) as the lesion's feature. The proposed method therefore has the potential for computer-aided diagnosis in breast tumors.