Malignant Breast Epithelium Research Articles

Immunocytochemical Evaluation of Neoplastic and Non-Neoplastic Breast Diseases with Mab A-80

Five hundred breast tissue samples from 404 cases were immunostained with A-80, a murine IgM Mab that recognizes a mucinous glycoprotein associated with exocrine differentiation. Samples included 196 primary breast carcinomas, 30 breast carcinoma metastases, 118 fibrocystic disease (FCD), and a further group of 84 samples of FCD from cases known to have breast carcinoma. These samples represented a broad spectrum of common and rare variants of carcinoma and FCD. Samples of fibroadenomas, lactating adenomas, cystosarcoma phylloides, gynecomastia, and normal breasts were similarly studied. The vast majority of carcinomas, 203/212 (95.7%) were immunoreactive; staining varied in extent and intensity, and was virtually unrelated to histologic type and to the presence or absence of recognizable glands. In samples including in-situ and infiltrating ductal or lobular carcinoma, reactivity was frequently stronger in the infiltrating components. No significant difference in reactivity between primary and metastatic carcinomas was noted. Of the group of 118 FCD, 27 were negative whereas 91 showed focal and weak staining. Seventy-two/84 FCD with associated carcinoma were immunostained; in 13 of those 72, staining was strong and extensive. Fibroadenomas, lactating adenomas, gynecomastia, and normal "resting" and lactating breast samples stained focally or not at all. Our findings indicate that Mab A-80 is an excellent immunohistochemical marker for the overwhelming majority of breast carcinomas whereas it marks weakly or not at all the majority of benign neoplasms and normal breast. Moreover, Mab A-80 recognizes a subset of FCD that includes proliferative variants associated with an increased incidence of carcinoma, and FCD in association with carcinoma. Questions regarding rare breast carcinomas that do not react with Mab A-80 remain unclear; yet, we believe that Mab A-80 is a highly promising marker of malignant and dysplastic breast epithelium.

Immunohistochemical analysis of the binding of human IgM to secretory component present in normal adult colon epithelia, but not in colon cancer and fetal colon epithelia

We have analysed the binding of human IgM to fetal, normal adult and malignant colo-rectal tissues. Using an indirect immunoperoxidase technique on sections of frozen tissues human IgM binds to all normal adult colo-rectal epithelia (n = 15) tested. By contrast, 9 out of 25 colo-rectal adenocarcinomas were negative, and in the remaining 16 the staining reaction varied from staining of all the cancer areas to focal staining of a few areas. Human IgM did not bind to 14 samples of fetal intestinal epithelium (gestational age of 6-14 weeks). The binding of IgM was found to be mediated by secretory component (SC) as anti-SC antibody (anti-SC) showed a similar staining pattern as IgM and the IgM binding could be blocked by anti-SC. SC was also demonstrated in glandular epithelia of sections of all normal breast epithelia but only in 10 out of 15 breast adenocarcinomas. The loss of IgM binding and SC could not be correlated to the morphology of the adenocarcinomas. The observations on fetal, normal adult and malignant tissue suggest that IgM binding and SC may be gradually lost during dedifferentiation of normal cells, to malignant colo-rectal or breast epithelia.

Growth control of normal and malignant breast epithelium

SynopsisWe review information highlighting the multiple roles of both steroidal (primarily oestrogen) and polypeptide regulators of mammary epithelial cell growth, emphasising the work of our laboratory. Effects of both classes of hormones are complex and involve multiple interactions with non-tumour, host tissue. Oestrogen may induce growth regulatory polypeptide growth factors and interact with them in hormone dependent breast cancer. Progression of hormone-dependent breast cancer to hormone independence may involve multiple genetic mechanisms of oncogene activation, loss of the oestrogen receptor, or loss of hormone responsivity of other gene products. Initial carcinogenesis and progression of mammary epithelium to cancer probably also requires both proliferative stimuli (oestrogen, polypeptide growth factors) and genetic damage, leading to qualitatively different hormonal responses (hormone responsive cancer). Future therapies should be designed to block hormonal stimulation better and to interfere with necessary activated or induced components of malignant progression such as oncogenes or polypeptide growth factors receptor systems.

Internal Antigens Accessible in Breast Cancer: Implications for Tumor Targeting

Proponents of monoclonal antibody (MAb)-mediated cancer therapy often assume that a major limitation in clinical application of MAbs is their lack of absolute specificity for malignant cells. In addition, the presence of surface target antigens is thought to be essential. These requirements may be more stringent than necessary for the clinical usefulness of MAbs. We have demonstrated selective localization of a MAb to keratin polypeptides in malignant breast epithelium under conditions of passive infusion of antibody in fresh surgical specimens of breast carcinoma. Although these proteins are normal intracellular constituents of epithelial cells throughout the body, localization of antikeratin antibodies only within the tumor population is most probably associated with the presence of cells permeable to macromolecules. This permeable tumor cell fraction could be recruited for targeting neighboring impermeable tumor cells with radioisotopes or other antitumor agents conjugated to antibodies directed against intracellular antigens.

Structural distinctions among human breast epithelial cells revealed by the monclonal antikeratin antibodies AE1 and AE3

Two monoclonal antikeratin antibodies, AE1 and AE3, were used in indirect immunocytochemistry to examine keratin expression in normal, benign proliferative, and malignant human breast epithelium. Both antibodies reacted strongly with most luminal cells in ducts and acini of normal gland. While AE1 did not stain myoepithelium, AE3 recognized myoepithelial cells of ducts but not acini, implying a cytoskeletal difference between the myoepithelium of these two components. Moreover, the antibodies reacted differently with the myoepithelium of intracanalicular as compared with pericanalicular types of fibroadenomas. Tumour cells of infiltrating ductal carcinomas with a prominent intraductal component stained more homogeneously with AE1 and AE3 than those without intraductal growth. The results provide evidence for two phenotypes of myoepithelial cells and for the presence of cryptic keratin epitopes in human breast epithelial cells. The finding that neither AE1 nor AE3 is a universal detector of these cells has important clinical and experimental implications.

Peanut lectin binding in breast carcinoma: Lack of correlation with estrogen receptor content

Previous reports have shown binding of peanut agglutinin (PNA) by immunoperoxidase techniques in normal, benign proliferative, and malignant breast epithelia. Correlation of binding with maturity, secretory activity, hormonal milieu, and tissue hormone receptor content has been described. To investigate the relationship between PNA staining by the avidin-biotin complex technique and estrogen receptor (ER) content, 79 breast tumors of different types and known tissue ER content were studied. Thirty-eight of 50 ER-positive cases were PNA-positive. Twenty of 29 ER-negative cases were PNA-positive. Statistical analysis shows the two factors to be independent (0.5 less than P less than 0.9). The literature on blood group antigens in breast carcinoma and histochemical applications of PNA is reviewed.

Immunohistochemical detection of ras oncogene p21 product in benign and malignant mammary tissue in man.

The monoclonal antibody RAP-5 generated against a synthetic peptide corresponding to amino acid positions 10-17 of the ras p21 protein was used in an immunohistochemical study of the expression of ras in normal, benign, and malignant breast epithelium in man. The staining intensity and intracellular distribution of RAP-5 was similar in the three epithelial populations and extended to other tissue elements including myoepithelial cells, smooth muscle, myelin, capillary endothelium, and stromal fibroblasts, as well as sebaceous glands and sweat glands overlying the breast. These results suggest that RAP-5 recognises a normal cellular component, the expression of which is not more enhanced in hyperplastic or neoplastic conditions. The detection of mutant forms of p21 exclusively expressed in malignant tumours requires that alternative reagents be developed.

Clonal growth of normal and malignant human breast epithelia.

We have developed an efficient method for the growth of colonies from single breast epithelial cells derived from nonmalignant [6], primary [7], and metastatic [1] surgical specimens. The immediate sources of the cells were primary and secondary mass cultures. An enriched culture medium and fibroblast feeder layers were used. A linear relationship between the number of cells cultured and the number of colonies obtained was found. Efficiency of colony formation was higher for those derived from nonmalignant specimens (mean 24%) than those derived from malignant specimens (mean 11%). Fibroblast feeder layers increased the efficiency of colony formation and also supported extended growth of colonies.

Reliability of blood pressure measurements: Implications for evaluating control programs: Donald S. Shepard, Veterans Administration Outpatient Clinic, 17 Court St., Boston, Massachusetts 02108

Five hundred breast tissue samples from 404 cases were immunostained with A-80, a murine IgM Mab that recognizes a mucinous glycoprotein associated with exocrine differentiation. Samples included 196 primary breast carcinomas, 30 breast carcinoma metastases, 118 fibrocystic disease (FCD), and a further group of 84 samples of FCD from cases known to have breast carcinoma. These samples represented a broad spectrum of common and rare variants of carcinoma and FCD. Samples of fibroadenomas, lactating adenomas, cystosarcoma phylloides, gynecomastia, and normal breasts were similarly studied. The vast majority of carcinomas, 203/212 (95.7%) were immunoreactive; staining varied in extent and intensity, and was virtually unrelated to histologic type and to the presence or absence of recognizable glands. In samples including in-situ and infiltrating ductal or lobular carcinoma, reactivity was frequently stronger in the infiltrating components. No significant difference in reactivity between primary and metastatic carcinomas was noted. Of the group of 118 FCD, 27 were negative whereas 91 showed focal and weak staining. Seventy-two/84 FCD with associated carcinoma were immunostained; in 13 of those 72, staining was strong and extensive. Fibroadenomas, lactating adenomas, gynecomastia, and normal “resting” and lactating breast samples stained focally or not at all.Our findings indicate that Mab A-80 is an excellent immunohistochemical marker for the overwhelming majority of breast carcinomas whereas it marks weakly or not at all the majority of benign neoplasms and normal breast. Moreover, Mab A-80 recognizes a subset of FCD that includes proliferative variants associated with an increased incidence of carcinoma, and FCD in association with carcinoma. Questions regarding rare breast carcinomas that do not react with Mab A-80 remain unclear; yet, we believe that Mab A-80 is a highly promising marker of malignant and dysplastic breast epithelium.

Long-term treatment and compliance: Judith K. Skinner, Cardiovascular Clinic, 3300 Northwest 56th, Oklahoma City, Oklahoma 73112

Five hundred breast tissue samples from 404 cases were immunostained with A-80, a murine IgM Mab that recognizes a mucinous glycoprotein associated with exocrine differentiation. Samples included 196 primary breast carcinomas, 30 breast carcinoma metastases, 118 fibrocystic disease (FCD), and a further group of 84 samples of FCD from cases known to have breast carcinoma. These samples represented a broad spectrum of common and rare variants of carcinoma and FCD. Samples of fibroadenomas, lactating adenomas, cystosarcoma phylloides, gynecomastia, and normal breasts were similarly studied. The vast majority of carcinomas, 203/212 (95.7%) were immunoreactive; staining varied in extent and intensity, and was virtually unrelated to histologic type and to the presence or absence of recognizable glands. In samples including in-situ and infiltrating ductal or lobular carcinoma, reactivity was frequently stronger in the infiltrating components. No significant difference in reactivity between primary and metastatic carcinomas was noted. Of the group of 118 FCD, 27 were negative whereas 91 showed focal and weak staining. Seventy-two/84 FCD with associated carcinoma were immunostained; in 13 of those 72, staining was strong and extensive. Fibroadenomas, lactating adenomas, gynecomastia, and normal “resting” and lactating breast samples stained focally or not at all.Our findings indicate that Mab A-80 is an excellent immunohistochemical marker for the overwhelming majority of breast carcinomas whereas it marks weakly or not at all the majority of benign neoplasms and normal breast. Moreover, Mab A-80 recognizes a subset of FCD that includes proliferative variants associated with an increased incidence of carcinoma, and FCD in association with carcinoma. Questions regarding rare breast carcinomas that do not react with Mab A-80 remain unclear; yet, we believe that Mab A-80 is a highly promising marker of malignant and dysplastic breast epithelium.

A method for distinguishing benign from malignant breast lesions utilizing antibody present in normal human sera

A sensitive immunoperoxidase technique was utilized 1) to detect the presence in normal human serum of antibody directed against breast carcinoma cells (tumor associated antibody--TAA) and 2) to determine whether this antibody could be used to discriminate between benign and malignant breast epithelium in sections of formalin fixed paraffin embedded tissue. A total of 16 benign and 13 malignant breast lesions were examined for evidence of binding of human immunoglobulin, before and after application of normal human AB serum containing the putative tumor associated antibody--TAA. Malignant cells showed significant binding of human immunoglobulin (TAA); benign or normal cells did not. Clear immunohistological separation of benign and malignant breast lesions appears possible by this method.

The presence and significance of the Thomsen-Friedenreich antigen in breast cancer

Serum levels of antibodies against the Thomsen-Friedenreich (TF) antigen were determined for a group of patients with malignancies of the breast, as well as a control group of healthy persons and patients with no breast disease. Despite recent claims of anti-TF levels being severely depressed in patients with breast cancer, we were unable to show any significant differences between the two groups. Standardised anti-TF containing sera or solutions of the TF specific agglutinin from peanuts (PNA) were absorbed with membrane preparations from normal and cancerous breast tissue, but again no differences in absorption were noted. Histological examination, by contrast, showed both free and sialic acid-covered receptors to be present on both normal and malignant breast epithelium. Based on these findings it was concluded that determination of serum anti-TF is an unsatisfactory method of diagnosing breast cancer and that the TF antigen cannot be considered to be carcinoma associated.

Glycoprotein synthesis as a function of epithelial cell arrangement: Biosynthesis and release of glycoproteins by human breast and prostate cells in organ culture

We demonstrate that a technique is available to investigate glycoprotein synthesis in organ cultures of human breast and prostate surgical specimens where the 3-dimensional epithelial cell arrangement remains intact. Malignant breast and prostate epithelium maintained their capacity to synthesize glycoproteins for at least 3 days as followed by the incorporation of [3H]glucosamine into macromolecules. Over 70% of incorporation was by malignant cells as judged by autoradiography. Labeled glycoproteins were released into glandular lumina and consequently into the culture fluid. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed predominantly one group of macrmolecules released with an apparent molecular weight of 48,000 +/- 6,000 daltons. This glycoprotein was found in all of the breast specimens studied, which included 1 medullary, 1 infiltrating lobular, and 8 infiltrating duct carcinomas. The pattern was independent of the availability of estrogen receptors. A similar glycoprotein was also observed in the culture media from a Grade I and a Grade II well-differentiated infiltrating prostate carcinoma. Incorporation was below the level of detection in 4 of 6 cases of benign prostatic hyperplasia. A more complex pattern of labeled glycoproteins was found in the media of a Grade II and a Grade III poorly-differentiated prostate carcinoma. The established human mammary carcinoma cell line MCF-7 synthesized and released a similar 48,000 molecular weight glycoprotein but additional components with larger molecular weights were also released. An intriguing interpretation that 3-dimensional tissue integrity restricts some glycoprotein synthesis is discussed. Cells grown in 2-dimensional monolayers could escape from such a topographic restriction and express additional families of glycoproteins.

Tritiated thymidine labeling index of benign and malignant human breast epithelium.

38 specimens of benign breast tissue from young women and 92 primary breast carcinomas were evaluated for tritiated thymidine ([3H]TdR) labeling index (TLI) by in vitro pulse labeling. The TLI on nonneoplastic, terminal breast ducts was significantly higher during the latter half than during the first half of the menstrual cycle (P less than 0.001), and a geometric mean TLI of 1.5 during the latter half of the cycle is consistent with approximately 47% turnover of these cells during the menstrual cycle. Ducts of fibroadenomas showed similar menstrual variation TLI. The range of TLI observed in the carcinomas was 0.04-18.6, arithmetic mean 3.7, geometric mean 2.1. The TLI of carcinomas was not significantly correlated with size of the tumor, but tended to be higher in women less than 50 yr old than in women older than 50 yr (P less than 0.05), and in the presence of two or more metastatic axillary lymph nodes than when fewer than two nodes were involved (P less than 0.02).