Immunofluorescence studies on sera of patients with breast carcinoma

Natural and adaptive IgM antibodies in the recognition of tumor-associated antigens of breast cancer (Review)

For early detection of cancer, education and screening are important, but the most critical factor is the development of early diagnostic tools. Methods that recognize the warning signs of cancer and take prompt action lead to an early diagnosis; simple tests can identify individuals in a healthy population who have the disease but have not developed symptoms. Early detection of cancer is significant and is one of the most promising approaches by which to reduce the growing cancer burden and guide curative treatment. The early diagnosis of patients with breast cancer is challenging, since it is the most common cancer in women worldwide. Despite the advent of mammography in screening for breast cancer, low-resource, low-cost alternative tools must be implemented to complement mammography findings. IgM is part of the first line of defense of an organism and is responsible for recognizing and eliminating infectious particles and removing transformed cells. Most studies on breast cancer have focused on the development of IgG-like molecules as biomarkers or as a treatment for the advanced stages of cancer, but autoantibodies (IgM) and tumor-associated antigens (proteins or carbohydrates with aberrant structures) have not been examined as early diagnostic tools for breast cancer. The present review summarizes the function of natural and adaptive IgM in eliminating cancer cells in the early stages of pathology and their value as early diagnostic tools. IgM, as a component of the immune system, is being used to identify tumor-associated antigens and tumor-associated carbohydrate antigens.

Bovine-associated mucoprotein: de novo synthesis by nonmammary tissues

Bovine tissues were cultured in vitro in the presence of carbon-14 amino acids and tritiated hexosamine to examine the de novo synthesis of the milk fat globule glycoprotein bovine-associated mucoprotein, by selected tissues. Among tissues examined, the relative synthesis of bovine-associated mucoprotein was highest in mammary tissue. The de novo synthesized bovine-associated mucoprotein in mammary and lacrimal gland cultures when examined for incorporation of carbon-14, had similar sedimentation profiles in sucrose density gradients and incorporated the same relative amount of carbohydrate. The bovine-associated mucoprotein synthesized by lung and spleen cultures sedimented in similar fashion to mammary gland bovine-associated mucoprotein when incorporation of carbon-14 was used as the marker, but it displayed greater heterogeneity when evaluated for tritium incorporation. Bovine-associated mucoprotein in the lung and spleen incorporated relatively less carbohydrate than that synthesized by mammary tissue. These findings support the concept of intertissue heterogeneity, which had been suggested by previous studies.

Circulating anti-tumor and autoantibodies in breast carcinoma: relationship to stage and prognosis

Serum antibodies to breast tumor antigen(s) and circulating autoantibodies were tested in 175 patients with various stages of carcinoma of the breast, followed for a mean period of 51 months. Antibodies to surface membrane and to cytoplasmic antigens of autologous and allogeneic tumor cells were measured. Peripheral lymphocyte count and skin reaction to six recall antigens were also tested. Patients with metastatic disease had significantly lower prevalence of antibodies to autologous tumor cells and lower total lymphocyte count than patients with early breast cancer. Patients with locally advanced disease (greater than or equal to 4 positive axillary nodes) had the highest frequency of anti-tumor antibodies, the second highest lymphocyte count, but with the lowest prevalance of autoantibodies. Presence or absence of anti-tumor or autoantibody did not correlate with results of skin tests or other standard blood tests. Among patients with locally advanced or metastatic breast cancer, those who had a positive skin test or whose lymphocyte count was 1500 to 2500 per cu mm had significantly better 5-year absolute survival rates (p = 0.04, p = 0.002, respectively). This study suggests that in patients with locally advanced or metastatic breast cancers, skin test reactivity and optimal peripheral lymphocyte count may be useful prognostic indicators. In contrast, neither the presence of anti-tumor antibodies to membrane or cytoplasmic antigens, nor the presence of autoantibodies, correlates with prognosis in patients with early or late breast cancers.

Leukocyte adherence inhibition assay in human pulmonary neoplasia

The hemocytometer leukocyte adherence inhibition technique was used to study cell-mediated immuno-activity of patients with lung cancer. KCl extracts (3.5 M) from the lung cancer cell line Calu-1 and the breast cancer cell line MCF-7 were used as antigens. Of 138 patients with lung cancer, 85% showed a positive response against the Calu-1 antigen. The response was independent of the histological type of the tumor and was the same among untreated patients, patients undergoing different types of treatment and patients who died within 3 months after blood collection. Twenty-five percent of the untreated lung cancer patients also reacted against the breast cancer antigen. Among lung cancer patients undergoing different types of treatment, 36% reacted while 50% of the patients who died within 3 months after blood collection reacted against the breast cancer antigen.

Role of circulating antibodies in the humoral leukocyte adherence inhibition response of lung and breast cancer patients

A modified leukocyte adherence inhibition (H-LAI) assay has recently been developed in which 0.25% serum from the patient is added to the assay system in combination with the relevant antigen. Trypsinized leukocytes from control persons are used as indicator cells. In the present work, the nature of the humoral factor in serum from breast and lung cancer patients is studied. 3.5 M KCl extracts from the cell lines MCF-7 and Calu-1 were used as breast and lung cancer antigen, respectively. It was found that the humoral factor involved in the H-LAI response was precipitated from the sera by addition of ammonium sulphate to 50% saturation. This factor could be removed by passage through an affinity column with the relevant antigen bound to the matrix. Stable complexes were formed between the humoral factor and the relevant antigen, and could be precipitated by polyethylene glycol. When different anti-immunoglobulins were added to the sera, the humoral factor was specifically removed by addition of anti-IgG antibodies. The data presented indicate that the humoral factor in sera from patients with breast and lung cancer is antitumor antibodies of IgG nature.

Autologous and homologous immunofluorescent antibody to established breast cancer cell lines

Indirect immunofluorescence tests were performed on 14 established human breast cancer cell lines using sera from a variety of subjects. Autologous reactions were studied on 10 cell lines, with positive reactions demonstrable in 8. Tests using sera from a randomly selected population of breast cancer patients showed reactivity in 40 to 66% depending on the target cell line used. Reactivity to other nonbreast cancer cell lines was rare. Several control populations were tested, including normal blood bank donors, persons with benign breast disease, and persons with other forms of cancer; immunofluorescent antibody was detected much less frequently in sera from these populations than those from the breast cancer group. Positive reactions remained in spite of absorption of serum with heterophile antigens, normal human breast tissue, and AB+ red blood cells. Thus established cell lines of human breast cancer possess antigens commonly recognized by sera from breast cancer patients.

Virus-like particles and macromolecules in human milk and breast tumors

Relevant data pertaining to present evidence for virus-like particles and virus-related macromolecules in human milk and breast tumors are presented. A critical review and discussion of reported observations concerning virus-related macromolecules will include RNA-directed DNA polymerase, viral antigens, and RNA related to murine mammary tumor virus and/or Mason-Pfizer monkey virus. From the standpoint of clinical applications, the finding of viral-related antigens in human breast tumors and evidence for specific host immune responses to one or more of these antigens may be especially pertinent. The latter data, therefore, will be discussed in depth as to possible employment of these parameters in diagnosis, prognosis and possible management of the human disease.

Fibroadenoma in oral contraceptive users: a histopathologic evaluation of epithelial atypia

We have reviewed histologically a series of 120 fibroadenomas which formed part of the case material from a previous case-control epidemiological investigation of the relationship between oral contraceptive use and breast disease. We evaluated the epithelial component of the fibroadenoma for degree of cytologic atypia. This study indicates that the reduced risk for fibroadenoma among long-term users of oral contraceptives does not vary according to the degree of epithelial atypia present. This is in contrast to our previously reported findings for fibrocystic disease, in which the decreased frequency of occurrence of the disease in long-term users of oral contraceptives was found only for cases with no minimal epithelial atypia.

Fibrocystic breast disease in oral-contraceptive users. A histopathological evaluation of epithelial atypia

Epidemiological studies show a lower frequency of fibrocystic breast disease among long-term users of oral contraceptives than among women who have never used them. Fibrocystic disease may be a precursor of breast cancer; yet the incidence of breast cancer does not appear to differ between pill-takers and nontakers. To resolve this conflict, we examined the problem from a histologic standpoint in 205 premenopausal women, and found that this decreased frequency applied only to fibrocystic disease in which epithelial atypia was minimal or absent. In women with marked atypia there was no significant difference in frequency among long-term users as compared to women who have never used oral contraceptives. These findings suggest that a spectrum of cystic disease exists and that the long-term use of oral contraceptives protects against the forms of fibrocystic disease that are not firmly associated with an increased risk of breast cancer, but not against the premalignant forms.

Immunology, tumor markers, and breast cancer

Although our knowledge of immunologic processes in breast cancer is still inadequate, many preliminary studies described here may yield valuable information after long-term patient follow-up. At present, there is no specific tumor marker diagnostic of breast cancer, but markers such as CEA, ferritin, immune complexes, and specially estrogen receptors have strong potential as prognostic indicators. As a group, breast cancer patients, as do those with other malignancies, demonstrate reduced immunologic capacity, therefore assays of nonspecific immune function may not be relevant. Assays of "specific" reactivity to breast tumor antigens, however, warrant further investigation as clinical tools. Application of immunotherapy to breast cancer is relatively recent and few trials have more than preliminary data. Determination of estrogen receptors should be included in future clinical immunotherapy protocols so that true evaluation of immunologic responses may benefit, hopefully, from our awareness of the endocrine milieu.

Isolation from patients with breast cancer of antibodies specific for antigens associated with breast cancer and other malignant diseases

Antibodies were specifically purified, with the use of pleural fluid antigens entrapped in a polyacrylamide gel as immunoadsorbent, from a pool of sera from patients with breast cancer and from the pleural effusion of an individual patient. The purified antibodies were radioiodinated and tested for capacity to bind to the pleural fluid adsorbent. Binding of the radiolabeled antibodies was inhibited by many of the sera from women with breast cancer to a much greater extent than by sera of healthy women. With purified antibodies originating from the serum, 52% of the breast cancer sera and 16% of sera from patients with other malignancies were more inhibitory than were 95% of the sera of healthy women. In the tests with antibodies eluted from pleural fluid, 24% of the breast cancer sera and 25% of the sera from patients with other neoplastic diseases were more inhibitory than were 95% of the normal sera. We concluded that sera of patients with breast cancer may contain antibodies against antigens associated with breast cancer as well as additional antibodies against antigens that are also found in patients with other neoplastic diseases or in normal individuals. Individual breast cancer sera may inhibit binding of the labeled antibodies against breast cancer owing to their content of antibodies, antigen(s), or both.

[Association between tumor immunology, stromal reaction, and tumor endocarditis (author's transl)]

Based on the observation that adenomatous carcinomas are frequently associated with tumor endocarditis, whereas undifferentiated tumors are not, autopsy material of tumor cases was examined for differences in the immune response with regard to the histological typing of the tumors. In the former group signs of stimulated cellular and humoral immune mechanisms were markedly stronger developed than in the latter group. From these findings it is suggested that tumor endocarditis represents an immune complex disease.

Immunofluorescence detection of casein in human mammary dysplastic and neoplastic tissues

To detect and localize casein in human mammary dysplastic and neoplastic tissues, an indirect immunofluorescence method has been devised. Anti-casein antibodies have been obtained from rabbits immunized with casein isolated from human milk. Cryostat sections post-fixed in alcohol and paraffin sections from routinely formalin-fixed tissues proved suitable. The immuno-fluorescence method revealed the presence of casein in epithelial cells in mammary dysplasia and in some, but not all, cases of carcinoma of the breast. Well differentiated (Grade I) carcinomas were shown to contain casein, mainly localized at the inner border of the epithelial cells; the milk protein was present also in cells metastatic in lymph nodes. In Paget's disease of the nipple, casein could be detected in neoplastic cells in the ducts and also in cells identifiable with the typical intra-epidermal Paget cells. This finding is evidence of a functional differentiation of Paget cells along lines proper to the mammary epithelium.

Breast cancer and the immune response

Patients with malignant disease including that of the breast may show specific immune reactions against their own tumours, and as the disease progresses other immune reactions may be depressed. The current controversy surrounding regional lymph node therapy in early breast cancer is discussed. Ideas about the further immunological investigation of patients with breast cancer are outlined.

Specific Immunogenicity of Human Breast Carcinoma Extracts in Rabbits

Absorbed serum from a rabbit immunized with an extract of a pool of 5 breast carcinomas yielded a single precipitation line when tested on the pooled tumors used to immunize and on single breast carcinomas, whether participating in the immunization or not. No precipitation was seen with control normal mammary tissues from the same patients. Antisera from 5 out of 9 rabbit immunized with different single breast carcinomas gave one precipitin line against the tumor used to immunize and also in cross-reaction against the other 4 mammary carcinomas positive in the direct test. No bands were obtained with normal mammary tissue extracts or with a fibroadenoma extract. A rabbit antiserum against the fibroadenoma was always negative on all the breast carcinoma extracts tested.