Flow cytometric analysis of estrogen, progesterone receptor expression and DNA content in formalin-fixed, paraffin-embedded human breast tumors.

Flow cytometric analysis of estrogen (ER) and progesterone (PgR) receptor expression in archival human breast tumors is relatively difficult. We have used enzyme digestion and microwave antigen retrieval procedures for multiparametric flow cytometric analysis of ER and PgR expression and DNA content in nuclei isolated from formalin-fixed/paraffin-embedded primary breast tumors. Deparaffinized rehydrated tissue sections treated with pepsin were subjected to microwave irradiation for unmasking of ER and PgR antigenic sites. Biotinylated ER antibody and streptavidin-fluorescein isothiocyanate (FITC) were used for ER labeling and PgR antibody with phycoerythrin labeled goat anti-mouse antibody was used for PgR labeling. Counter staining with propidium iodide-RNase was used for determination of cellular DNA content. Our results show that enzyme digestion and microwave treatment of formalin-fixed, paraffin-embedded breast tumors can be successfully used for the multiparametric analysis of nuclear hormone receptor expression and DNA content by flow cytometry.     

Flow cytometric determination of DNA content in malignant and benign bone tumours

The nuclear DNA content of 38 malignant and 25 benign bone tumours was measured by flow cytometry. The specimens were taken either from biopsies or from surgical specimens. Seventeen of 26 primary malignant bone tumours were aneuploid, 15 had a single aneuploid DNA content, and 2 had a biclonal abnormality. Thirteen of 15 osteosarcomas were aneuploid, but only 2 of 6 chondrosarcomas showed an aneuploid DNA content. Six of 12 metastatic malignant bone tumours were also aneuploid. All 25 benign tumours had a diploid DNA content. Cell cycle analysis showed that the proportion of cells in S- and G2M-phases was higher in the malignant compared to benign tumours, indicating a higher proliferative activity. The increase was statistically significant (p less than 0.05) both in diploid and in aneuploid tumours. Among five tumours studied after chemotherapy, four displayed a marked hyperdiploid abnormality. Aneuploidy and high proliferative activity both were highly associated with malignant bone tumours, suggesting that DNA flow cytometry may be an adjunct in the assessment of malignancy of bone tumours.     

Flow cytometric analysis of DNA content for ploidy determination in human solid tumors.

Flow cytometric studies of cellular DNA content were conducted in 26 patients with a variety of neoplasms. Cell dispersal was achieved with pepsin treatment, and a combination of ethidium bromide and mithramycin was used as DNA specific staining procedure. All measurements were conducted with a new sheath flow chamber in a PHYWE ICP 11 pulse cytophotometer. All but one patient with multiple myeloma had unimodal tumor cell DNA distributions. With human granulocytes as reference standard, 24 of 26 tumors were aneuploid; and of these, 23 showed varying degrees of hyperdiploidy. Except for one patient, ploidy abnormalities were stable on repeat examination.     

Flow cytometric study of DNA distribution in cytopunctures of benign and malignant breast lesions

One hundred seventy-eight cytopunctures of mammary lesions were obtained for cytologic diagnosis and flow cytometric (FCM) analysis of the nuclear DNA content. All lesions were excised and evaluated histologically; 106 were carcinomas and 72 were benign lesions. The benign lesions showed a diploid DNA content, with one exception. Among the 106 carcinomas, 35 (33%) were diploid, 14 (13%) were tetraploid and 57 (54%) were aneuploid. For 79 carcinomas, the relationship between ploidy and (1) "T" and "N" of TNM staging, (2) the histologic grading of Scarff, Bloom and Richardson, (3) axillary nodal involvement, (4) the presence of estrogen and progesterone receptors, (5) age and (6) menopausal status was investigated. The percentage of aneuploidy was significantly higher (P less than .05) in grade III tumors as compared to grade I tumors. There was no significant relationship between aneuploidy and the other factors. However, a trend was observed between the lack of steroid receptors and a high probability of the tumor being aneuploid. FCM DNA analysis was also carried out on breast carcinomas obtained at surgery in 40 patients for whom FCM DNA analysis had previously been performed on breast cytopuncture specimens. The FCM DNA analyses were found to be best performed on the samples obtained by cytopuncture, which may increase the yield of tumor cells.     

Keratin polypeptide distribution in benign and malignant breast tumors: subdivision of ductal carcinomas using monoclonal antibodies

Monoclonal antibodies which recognize one or only a few keratin polypeptides have been used to study the distribution of different keratins in benign and malignant breast lesions by immunocytochemical methods. Seven monoclonal antibodies which recognized either different keratin polypeptides by immunoblotting techniques, or identified different epithelial cell types in complex tissues were used. In two mastopathies and three fibroadenomas the antibody lu5 stained luminal cells as well as myoepithelial cells. In contrast the antibodies CK7, Troma 1, CK2 and KA4 labeled only luminal cells, whereas antibody CKB1 decorated only myoepithelial cells. All 15 ductal carcinomas showed a uniform staining of tumor cells with the antibodies Troma 1, CK2, KA4 and lu5. The antibody CK7 also stained all ductal carcinomas, but in two specimens the staining was heterogeneous. The antibody CKB1 decorated only the pre-existing myoepithelial cells in 11 of 12 ductal carcinomas but in the remaining specimen the tumor cells were also strongly positive. Tumor cells in lobular carcinomas were labeled by antibodies CK7, Troma 1, CK2, KA4, bu not by CKB1. The antibody CKS1 showed no staining of any of the benign and malignant breast lesions.     

DNA content in fresh versus paraffin-embedded tissue. Flow cytometric analysis of 100 tumors.

DNA ploidy analysis was determined on 100 consecutive tumors from a wide variety of sites using both fresh and paraffin-embedded tissue on the same specimen. The correlation coefficient (r) value between the methods was 0.85. Aneuploidy was detected by both methods in 51/100 (51%) of the cases. Fresh tissue analysis yielded 10 additional cases (overall 61% aneuploidy) not detected on corresponding paraffin-embedded sections, whereas paraffin-embedded analysis detected 4 additional cases (overall 55% aneuploidy) not revealed by fresh tissue analysis. Fresh tissue analysis produced lower coefficients of variation and resulted in a cleaner preparation with less cellular debris. Fresh tissue analysis was also superior to paraffin for the detection of hypodiploid, near-diploid and multiple peaks. Analysis of paraffin-embedded material allows examination of archival tissue and provides a more rapid means of long-term follow-up and statistical correlations for prognostic studies. Although the overall correlation of both methodologies for DNA analysis showed a minimal variation in results, in our experience fresh tissue analysis has an advantage and is preferable, when available, for ploidy analysis.     

Flow cytometric analysis of DNA aneuploidy in primary and metastatic human solid tumors

DNA histograms were measured by flow cytometry for 656 human solid tumors (365 primary and 291 metastatic). The proportion of aneuploid cells in cell suspensions obtained by mechanical disaggregation was significantly higher than those obtained after enzymatic disaggregation (collagenase + DNAse) of the same tumor. A strong correlation was observed between the values of DNA-indices measured after staining with propidium iodide and with 4',-6-diamidino-2-phenylindole (r = 0.97). Aneuploid cells were observed in 430 tumors (66%); 30 of these had two aneuploid stemlines, and two had three aneuploid stemlines. The overall frequency of aneuploidy was 61% among primary and 71% among metastatic tumors. The median value of the DNA index was 1.67 for 224 primary aneuploid tumors and 1.68 for 206 metastatic aneuploid tumors. For most diseases, the largest proportion of aneuploid primary and metastatic tumors had DNA-indices in the hypertriploid region. No major differences in frequency and degree of aneuploidy was observed between primary and metastatic tumors. For carcinomas of the bladder and prostate, frequency of aneuploidy was higher among poorly differentiated, than among moderately and well-differentiated tumors. For carcinomas of the breast and for sarcomas, tumors with DNA-indices of greater than 2.0 were observed mostly in the poorly differentiated group. For patients with carcinomas of the bladder and prostate most tumors at earlier stages of disease were diploid; whereas most tumors at later stages of disease were aneuploid. For patients with carcinomas of the ovary, colon, and kidney, no relationship between stage of disease and aneuploidy was evident.     

Flow cytometric analysis of human breast tumors and assessment of in vitro chemosensitivity by clonogenic assays

We report a double-agar clonogenic system adapted to human breast cancer. We optimized the conditions for cell growth and clonogenicity with respect to hormones (insulin, estradiol, progesterone) and components of the extracellular matrix (collagen, laminin and fibronectin). Using our experimental improvements, 67% of the breast tumor samples received were grown successfully. Tests on 21 tumors with three agents: Doxorubicin, Methotrexate and 5-Fluorouracil permit objective discrimination of the in vitro pharmacosensitivity of human breast tumors. Flow cytometric analysis reveal that 64% of the tumors were diploid and 36% were aneuploid. The aneuploid tumors grew better in the double agar layer system used for the clonogenic assay. The diploid tumors were especially rich in estrogen (ER⁺) and progesterone (PR⁺) receptors whereas the aneuploid tumors were mostly estrogen and progesterone receptors negative (ER^–/PR^–). Finally, we noted no difference in drug responsiveness depending on the tumor ploidy and steroid receptor content.Abbreviations DCC dextran coated charcoal - DI DNA index - DXB Doxorubicin - ECM extracellular matrix component - ER estrogen receptors - FCM flow cytometry - 5-FU 5-Fluorouracil - HTSCA human tumor stem cell assay - MTX Methotrexate - PBC primary breast carcinoma - PI proliferative index - PR progesterone receptors - SPF S phase fraction     

Flow cytometric DNA content of fresh tumor specimens using keratin-antibody as second stain for two-parameter analysis.

Studies concerning flow cytometric assessed DNA content reveal problems in interpretating DNA histograms of tumor specimens. The main problems are histograms with a broad coefficient of variation in the G0/G1 fraction; a high G2M fraction and samples with a low percentage of tumor cells. Therefore, in the present study, 382 fresh tumor specimens of carcinomas were analysed routinely, double labeled with, on the one hand, propidium-iodide for assessing DNA content and, on the other, a monoclonal keratin-antibody for marking epithelial and tumor cells. Of the 311 tumor samples, using single parameter analysis 165 (54%) were classified as DNA aneuploid and 146 (46%) as DNA "euploid." By double parameter analysis, 224 (72%) samples were keratin positive and 87 (27%) keratin negative and, of the 224 keratin positive tumors, 175 (78%) were DNA aneuploid and 49 (22%) DNA euploid. The DNA histograms of single and double parameter analysis were compared and it was concluded that in 24 cases (11%) keratin labeling was necessary to recognize DNA aneuploidy. In another 23 (10%) cases, keratin labeling was helpful in assessing DNA aneuploidy. Finally when the results of the 311 samples were combined, 215 (68%) were scored as DNA aneuploid and 99 (32%) DNA euploid. Thus the overall gain in assessing DNA aneuploidy using the double labeling technique is 14%. In conclusion, it is shown that keratin labeling on fresh tumor cell suspensions of epithelial tumors is of additional value in establishing DNA content. Because single parameter DNA assessment is adequate in approximately 60% of the tested samples, the double labeling technique can be performed routinely, or after initial single parameter DNA assessment. Histograms having a broad CV and/or a high G2M are good candidates for the double labeling technique. Using this technique, DNA-content assessment becomes more reliable.     

Flow cytometric analysis of DNA stemline heterogeneity in primary and metastatic breast cancer.

Flow cytometric DNA-ploidy analysis was used to investigate intratumor DNA stemline heterogeneity in primary breast carcinomas and lymph node metastases (LNM). The study was done in tumor specimens from 44 patients 35 of whom had LNM. In all, measurements were done in 214 different samples of primary tumors and 211 lymph nodes. Sixty-one percent (27/44) of the primary tumors were found to have multiple DNA aneuploid stemlines when the data of the separate samples per tumor (mean 4.9) were compared. Only five of 44 (11%) primary tumors were DNA diploid; two of these had DNA aneuploid metastases. Statistical analysis of these results indicated that, on average, four samples are needed for reliable determination of the DNA ploidy status of primary tumors by flow cytometry. In the majority of the cases (26/35), distinct tumor DNA stemlines found in LNM were also present in the primary tumor, which suggests that the generation of DNA ploidy diversity may have taken place prior to metastasis. Multiploidy was not related to tumor size but, particularly for LNM, was significantly correlated with age (r = 0.40, P = 0.02). The results of this study support the view that breast cancer is an extremely heterogeneous disease and that underestimation of this factor might account for the disagreement in literature about the prognostic value of DNA ploidy determinations.     

Flow cytometric analysis of erythrocyte populations in Tn syndrome blood using monoclonal antibodies to glycophorin A and the Tn antigen.

Flow cytometric analysis employing monoclonal antibodies to the Tn antigen and glycophorin A was used to characterize the erythrocyte populations present in blood samples from individuals with Tn syndrome. Four monoclonal antibodies specific for the Tn antigen, Gal-NAc monosaccharide, on human erythrocytes were obtained from a fusion of splenocytes from a Biozzi mouse immunized with red cells from a Tn individual. These monoclonal antibodies specifically recognize GalNAc monosaccharide sites located on the erythrocyte cell surface sialoglycoproteins, glycophorin A and glycophorin B, and do not bind to fixed normal red cells presenting the Neu-NAc alpha 2-3Gal beta 1-3(NeuNAc alpha 2-6)GalNAc alpha 1-O-Ser(Thr) tetrasaccharide or to fixed neuraminidase-digested cells presenting the Gal-GalNAc disaccharide. The percentages of Tn-positive red cells in samples from six unrelated Tn donors ranged from 28 to 99%. Binding of the glycophorin A-specific monoclonal antibodies showed that the erythrocytes composing the Tn-negative fraction presented normal amounts of the M and N epitopes on glycophorin A. The presumed somatic mutational origin of Tn-positive cells was tested in blood samples from five normal donors; three possible Tn cells were observed after analysis of a total of 1.1 x 10(7) erythrocytes, suggesting that the frequency of such cells in normal individuals is less than 1 x 10(-6).     

Differential expression of decorin by human malignant and benign vascular tumors.

An increasing amount of evidence indicates that a small extracellular chondroitin/dermatan sulfate proteoglycan, decorin, is indirectly involved in angiogenesis. Given that angiogenesis is a sine qua non for tumor growth and progression, we attempted to examine whether human malignant vascular tumors differ from human benign vascular tumors in terms of their decorin expression and synthesis. CD31 immunostaining demonstrated that the human malignant vascular tumors Kaposi's sarcoma and angiosarcoma were filled with capillary-like structures, whereas in benign cavernous and capillary hemangiomas, blood vessels were not as abundantly present. By utilizing in situ hybridization and immunocytochemical assays for decorin, we showed that there was no detectable decorin mRNA expression or immunoreactivity within the tumor mass in the Kaposi's sarcoma or angiosarcoma group. Instead, decorin was expressed in the connective tissue stroma lining the sarcoma tissue. In contrast to sarcomas, in hemangiomas, decorin mRNA expression and immunoreactivity were observed also within the tumor mass, particularly in the connective tissue stroma surrounding the clusters of intratumoral blood vessels. Finally, distribution of type I collagen was found to be similar to that of decorin in these tumor tissues. Our findings can be explained with different states of angiogenesis in dissimilar growths. In sarcomas, angiogenesis is extremely powerful, whereas in hemangiomas, angiogenesis has ceased. Thus, decorin is likely to possess a suppressive effect on human tumor angiogenesis in vivo, as previously described by studies using different experimental models. Decorin certainly provides a usable biomarker for distinguishing between benign and malignant vascular tumors in patients.     

Flow cytometric analysis and sorting of human endometrial cells after immunocytochemical labeling for cytokeratin using a monoclonal antibody

Endometrial cells in suspension were stained with propidium iodide and a monoclonal antibody against a cytokeratin intermediate filament protein specific for glandular and columnar cells (RGE 53). In this way columnar epithelial cells of the normal endometrium and of adenocarcinomas can be distinguished and separated by flow cytometry from non-epithelial cells (fibroblasts and inflammatory cells) and squamous epithelial cells, all of which are negative for RGE 53. This makes it possible to analyse and also sort pure fractions of this particular tissue type for further studies. The use of propidium iodide allows simultaneous DNA flow cytometry of these columnar epithelial cells. Therefore, the use of antibodies to cytokeratin in combination with propidium iodide can be of help in analyzing and sorting pure fractions of both normal and malignant cells. This allows a more refined examination of complex cell mixtures using flow cytometry.     

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.     

Flow cytometric DNA analysis of the human cervix affected by human papillomavirus and/or intraepithelial neoplasia

The relative DNA contents of 164 cellular samples from 59 patients affected by the viral cytopathic effects (VCE) of human papillomavirus (HPV) infection and/or by cervical intraepithelial neoplasia (CIN) and 12 cellular samples from 12 normal donors were analyzed by flow cytometry (FCM) with the aim of correlating the cytometric measurements with the morphologic and etiologic parameters. The unselected group of 59 patients was found to be characterized by statistically significant differences in average ages in the VCE and CIN (31.4 years) and CIN only (44.8 years) subgroups. Of the pathologic samples, 32 (54%) exhibited at least one cell subpopulation with an abnormal DNA content; in all but 2 of those cases, a diploid cell subpopulation was also present. The results indicate a relationship between the FCM ploidy and the morphologic classification, as shown by the increase in the occurrence of subpopulations with abnormal DNA contents from VCE only (38%) to VCE + CIN 1 (57%), to VCE + CIN 2/3 (70%). These results suggest that cytometric parameters, in association with the determination of the HPV types and in parallel to the colpocytohistopathologic criteria, can contribute to a more accurate characterization of cervical lesions in diagnostic and prognostic terms.     

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

Summary 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 RI-CEO-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-LON-LC28 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.     

Flow and image cytometric DNA ploidy,including 5c exceeding cells,of serous borderline malignant ovarian tumors. Correlation with clinicopathologic characteristics

OBJECTIVE: To analyze DNA ploidy of serous borderline ovarian tumors by flow cytometry (FCM) and image cytometry (ICM), with 5c exceeding cells also analyzed, and to evaluate their correlation with clinicopathologic characteristics of patients and tumors. STUDY DESIGN: Cell suspensions were prepared according to a modified Hedley method from formalin-fixed, paraffin-embedded tissue blocks of 43 tumors. One part of the suspension was used for flow cytometric measurement; from the other part, filter slides were prepared for ICM. RESULTS: FCM and ICM found 2 aneuploid (peridiploid) serous borderline ovarian tumors, and FCM found 1. ICM found 3 tumors with 5c exceeding cells and 2 tumors with octaploid cells. There was no correlation between DNA aneuploidy and presence of 5c exceeding cells with tumor size, International Federation of Gynecology and Obstetrics stage or survival. CONCLUSION: The results confirm a good correlation between FCM and ICM DNA ploidy and the ability of ICM to detect 5c exceeding cells. The prognostic value of DNA ploidy and 5c exceeding cells in serous borderline malignant ovarian tumors warrant further evaluation.