Clinical relevance of immune complexes, associated antigen, and antibody in cancer

Role of Immune Response in the Prognosis of Carcinoma of the Uterine Cervix: Can in Vitro Analysis Provide a better Framework for more Effective Management?

Cancer of the uterine cervix is the single largest female malignancy in India and also remains a major problem facing oncologists in other parts of the world. While advances in radiation therapy and surgical techniques have made the treatment of cervical carcinoma impressive, limitations to successful management still remain. In fact, the 5-year survival rate, stage for stage, has not improved in the United States or world wide in the past 40 years. With an estimated half a million women developing this disease annually, this lack of improved survival poses an international unresolved health problem. Immune response has been shown to be a major factor involved In the course of the disease for this cancer. Immunologic monitoring was also shown to be of effective value in assessing the prognosis for cervical carcinoma. We studied the various immunologic abnormalities in cervical cancer, the effects of radiation therapy on immune function, prospects of an immunologic staging system, the relationship between human papillomavirus infection and the Immune response, and the possibility of using in vitro Immunologic assessment to provide a better framework for more effective management of cancer of the uterine cervix.

Breast cancer humoral immune response: involvement of Lewis y through the detection of circulating immune complexes and association with Mucin 1 (MUC1)

Background

In cancer patients, MUC1 glycoprotein may carry Lewis y which could be involved in immune response. Purposes: 1- to evaluate the presence of Lewis y and MUC1 in circulating immune complexes (Lewis y/CIC and MUC1/CIC, respectively) and their correlation; 2- to analyze the possible presence of Lewis y in carbohydrate chains of tumoral MUC1 glycoprotein and 3- to correlate serum and tissue parameters considered.

Methods

Pretreatment serum and tissue breast samples from 76 adenocarcinoma, 34 benign and 36 normal specimens were analyzed. Anti-MUC1 and anti-Lewis y MAbs were employed. To detect Lewis y/CIC and MUC1/CIC, ELISA tests were developed; serum samples containing MUC1 were previously selected by Cancer Associated Serum Antigen (CASA). Immunoprecipitation (IP) was performed in 9 malignant, benign and normal samples and analyzed by SDS-PAGE and Western blot. Lewis y and MUC1 expression was studied by immunohistochemistry (IHC). Statistical analysis was performed employing principal component analysis (PCA), ANOVA, Tukey HSD, Chi square test and classical correlation (p < 0.05).

Results

By ELISA, Lewis y/IgM/CIC levels showed statistically significant differences between breast cancer versus benign and normal samples; mean ± SD values expressed in OD units were: 0.525 ± 0.304; 0.968 ± 0.482 and 0.928 ± 0.447, for breast cancer, benign disease and normal samples, respectively, p < 0.05. Lewis y/IgG/CIC did not show any statistically significant difference. MUC1/IgM/CIC correlated with Lewis y/IgM/CIC. By CASA, 9 samples with MUC1 values above the cut off were selected and IP was performed, followed by SDS-PAGE and Western blot; bands at 200 kDa were obtained with each MAb in all the samples. By IHC, with C14 MAb, 47.5%, 31% and 35% of malignant, benign and normal samples, respectively, showed positive reaction while all the samples were positive with anti-MUC1 MAb; in both cases, with a different pattern of expression between malignant and non malignant samples.

Conclusion

Our findings support that in breast cancer there was a limited humoral immune response through Lewis y/IgM/CIC levels detection which correlated with MUC1/IgM/CIC. We also found that Lewis y might be part of circulating MUC1 glycoform structure and also that Lewis y/CIC did not correlate with Lewis y expression.

Monoclonal antibody-based ELISA to detect glycoprotein tumor-associated-antigen-specific immune complexes in cancer patients

This report describes the development and applicability of a tumor-associated-antigen-specific immune complex (IC) detection assay to denote the presence of tumor cells in a cancer host. This assay utilizes a murine monoclonal antibody, AD1-40F4, which was produced to a glycoprotein tumor-associated antigen (TAA). In Western blot, the murine monoclonal antibody recognized a 90-100 kD subunit of the antigen. This antigen is immunogenic in cancer patients and induces formation of endogenous antigen-antibody complexes. Analysis of 250 sera from normal individuals and 419 sera from cancer patients revealed that a significantly (P less than .0005) greater proportion (234/419; 55.9%) of cancer sera was positive for the marker than the normal sera (8/250; 3.2%). The incidence of the 90 kD-TAA-specific-IC was consistently and significantly higher in melanoma (58.5%; 38/65), sarcoma (52.9%; 83/157), and carcinoma of breast (50.9%; 58/114), lung (68.2%; 30/44), and colon (64.1%, 25/39) than in the normal group. The age of serum donors did not affect the incidence of the reactivity. Also, at least in the cancer group the gender of the serum donor did not affect the incidence of the 90 kD-TAA-specific-IC positivity. In a retrospective study where sequential serum samples obtained postoperatively from 105 patients with melanoma were analyzed, the 90 kD-TAA-specific-IC could be detected in 72 (69%) of patients several years before the appearance of clinically detectable disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunocompetence in lung cancer. Relationship to extent of tumor burden and histologic type

In vitro assays of immunocompetence were done in 60 patients with differing extents of tumor load and various histologic types of lung cancer and were compared to values obtained for 60 normal controls. Profound alterations in monoclonal antibody-defined T-lymphocytes and circulating B-cells were seen. All patients showed impaired blastogenic response to the mitogens used with the exception of a normal response to pokeweed mitogen (PWM) in patients with localized disease. Increase levels of serum IgG were seen in patients with localized disease whereas high levels of IgA was seen in patients with more advanced disease. Distant metastases were associated with low IgM levels. All patients studied regardless of stage and histologic type had elevated levels of circulating immunocomplexes. These findings indicate gross immunologic abnormalities in these patients.

Immune reactive proteins as prognostic and clinical markers in malignant cervical neoplasia

The significance of immune reactive proteins in malignant cervical neoplasia, with particular reference to its prognostic and clinical relevance, was studied in 229 patients. All stages of the disease showed elevated levels of circulating immune complexes (CIC). Patients with stages I/IIA showed elevated levels of IgG, whereas those with stages III and IV showed depressed IgM levels. In the case of IgA, the situation was reversed: patients with advanced disease showed increased levels. Radiotherapy resulted in highly elevated levels of CIC, IgG, and IgA. However, in patients who remained disease-free after radiation treatment, levels of these proteins came down, often falling below pretreatment levels. On the other hand, patients developing recurrent disease showed sustained, high levels of CIC and IgA, with IgG as an isolated case in stage I/IIA. The present study therefore shows that although these increases were non-tumour-specific, patients with persistent elevation of CIC and IgA levels were at much greater risk of developing recurrent disease, thereby proving the merit of these substances as markers in prognosticating the course of disease in malignant cervical neoplasia.

Tumor-associated blood group antigen expressions and immunoglobulins associated with tumors

As outlined in Figures 1 and 2, the biosynthetic pathways for the expression of the A, B and H, and the Lewis determinant carbohydrate sequence structures, as well as sialylated structures, involves both type 1 and type 2 precursor chains (which may be present as glycolipids and N- or O-linked glycoproteins), and many glycosyltransferases. For tumor cells, there appears to be increased expressions of fucosyl- and sialyltransferases yielding such structures as the Le(x), sialyl-Le(a), and many other similar determinants, which are not found on the normal cell progenitor of the tumor. The types of structures expressed on tumor cells is dependent on the particular fucosyl-, sialyl- and other glycosyltransferase genes activated in the transformation and tumor progression events, the availability of the substrates for the glycosyltransferases (both the precursor sequences and the nucleotide-sugar substrates) which is partly dependent on metabolites available to the tumor mass, and on the genotype of the individual regarding particular glycosyltransferases. Both the loss of A, B and/or H blood group antigen expressions of tumor cells and the relative expressions of the Lewis and sialylated-oligosaccharide determinants may be a consequence of the competing biosynthetic pathways and the glycosyltransferases for common substrate sequences, as well as due to the loss of particular glycosyltransferases concomitant with transformation. All of these factors probably account for the variable expressions of the complex of carbohydrate sequence determinants when comparing tumor sections of different individuals as well as the heterogeneity of expression of particular determinants within a single tumor tissue section. As described above, the A, B and/or H determinants, and the precursor sequences, are also expressed to differing extents on epithelial cells depending on the tissue type and cellular location in the tissue. Thus, the differentiation state of the particular epithelial cell also determines the quantity and types of carbohydrate sequences expressed. However, because of the complex nature of the competing biosynthetic pathways for the carbohydrate sequences of glycolipids and glycoproteins, and the relative activations of fucosyl- and sialyltransferases of tumor cells, it would seem that simple deductions as to the state of differentiation of particular tumors with A, B, H and precursor sequence expressions is not warranted.(ABSTRACT TRUNCATED AT 400 WORDS)

Recovery of a cell surface fetal antigen from circulating immune complexes of melanoma patients

A well-characterized 69.5 x 10(3) dalton glycoprotein fetal antigen (FA), isolated from the spent culture medium of a melanoma cell line, UCLA-SO-14 (M14), was utilized to characterize the antigen component of circulating immune complexes (CIC) from melanoma patients. Ten serum samples from five patients with stage II melanoma at 1 and 4 months prior to the clinical detection of recurrent disease were selected for study. The CIC were dissociated with low pH and ultrafiltered through a 100 x 10(3) dalton exclusion limit membrane. The low pH treatment resulted in an increase in antibody titer in eight of ten serum samples. The antibody activity in membrane immunofluorescence was quantitatively inhibited by the filtered antigen fraction and purified FA, suggesting the presence of anti-FA antibodies in the treated serum, which possibly were complexed with FA in the untreated sample. As determined by competitive inhibition in an enzyme-linked immunosorbent assay, the filtrate (antigen fraction) contained an antigen that was immunologically similar to FA. These results clearly demonstrate that FA, expressed on the cell surface of melanoma cells, is present in CIC of selected melanoma patients.

Prognostic and pathogenetic implications of immune complexes in human cancer

The dynamic relationships of circulating immune complexes (CIC) and associated immune reactants to stage of disease and prognosis in cancer patients have been evaluated for malignant melanoma. Patients were divided into group I patients, with no evidence of disease at sample time; group II patients, with minimal tumor burden; and group III patients, with advanced metastatic disease. By means of single- and serial-sample determinations, we have demonstrated correlation of CIC concentration, size, and composition to tumor burden, disease progression, and high risk of disease recurrence. In view of the phenotypic heterogeneity of antigen expression in malignant melanoma, we have extracted, purified, and utilized melanoma-associated antigens (MAA) from CIC, and human oncofetal antigens (HOFA) from fetal liver cells, and reacted them with patients' sera in an in vitro model that simulates tumor burden changes. The observed changes in CIC concentration and lattice size upon reaction with MAA and HOFA demonstrated a significant (p less than or equal to 0.001) relationship to patients' in vivo tumor burden, as well as to the origin of serum and antigen involved. Our results suggest a homeostasis of CIC size and concentration to associated antibodies and antigens operational in malignant melanoma patients' sera. In addition, we have demonstrated how the monitoring of more than one immune reactant, characterization of CIC size and composition, and evaluation of resulting reequilibrium caused by in vitro addition of antigen or antibody, could allow for an improved assessment of humoral immunity and its related pathogenetic effects in cancer patients.