cefoxitin and Carcinoma

In this study, we discuss the use of glycopeptides containing tumour-associated carbohydrate antigens (TACA) as preventive vaccines for carcinomas. The results of our recent studies suggest that CD8(+) cytotoxic T cells are capable of recognizing small TACA in a conventional class I MHC-restricted fashion. TACA-specific T-cell receptors are highly degenerate and their fine specificity includes the glycosylated amino acid linker together with the sugar moiety. TF, a disaccharide and Tn, its immediate precursor, are TACA largely expressed in carcinomas that can be successfully used as vaccines when conjugated to designer peptide backbones with optimal binding affinity for class I MHC molecules.

Topics: Animals; Antigens, Tumor-Associated, Carbohydrate; Cancer Vaccines; Carcinoma; Glycopeptides; H-2 Antigens; Histocompatibility Antigens Class I; Humans; Mice; Receptors, Antigen, T-Cell, alpha-beta; T-Lymphocytes, Cytotoxic; Vaccination

Resected carcinoma patients were immunized 3-5 times with ovine submaxillary gland mucin (OSM) containing predominantly sialylated Tn (sTn), completely desialylated ovine submaxillary gland mucin (dOSM) containing predominantly Tn, or 50% desialylated OSM containing Tn and sTn plus bacillus Calmette-Guerin (BCG) as an immunologic adjuvant. Pre- and postimmunization sera were quantified by ELISA, whole-cell ELISA, and immune stain dot blots. Fifteen of 17 patients produced IgG antibody titers from 40 to 5120 times more reactive with OSM and dOSM postimmunization. More importantly, these IgG antibodies reacted with LS-174T, a human colon carcinoma cell line. Significant DTH-like responses (1-17 cm) were observed in 15 of 17 patients; the strength of these responses was dependent on the presence or absence of sialic acid. Biopsies of these DTH-like reactions revealed infiltration with some CD8+ lymphocytes and mast cells. These results suggest that a single 9-carbon sugar can affect cellular immune responses to mucin antigens. It is thought that these large erythematous, nonindurated cellular reactions are antibody-mediated Arthus-like reactions. OSM, and especially dOSM, were also found to inhibit lymphocyte proliferation.

Topics: Adjuvants, Immunologic; Animals; Antibody Formation; Antigens, Tumor-Associated, Carbohydrate; BCG Vaccine; Cancer Vaccines; Carcinoma; CD8-Positive T-Lymphocytes; Cell Proliferation; Colonic Neoplasms; Enzyme-Linked Immunosorbent Assay; Humans; Immunity, Cellular; Immunoglobulin G; Mast Cells; Mucins; Submandibular Gland; Swine; Tumor Cells, Cultured

We have synthesized various formulations that have potential for active specific immunotherapy (ASI) of human cancers. Sialyl-Tn (STn) is a potentially important target structure for ASI because its expression on mucins is a strong, independent predictor of poor prognosis, suggesting that it may have functional significance in the metastatic process. In this first pilot study of synthetic sialyl-Tn hapten conjugated to keyhole limpet hemocyanin (STn-KLH), with Detox adjuvant, toxicity and humoral immunogenicity were assessed in 12 patients with metastatic breast cancer. Toxicity was minimal, restricted to local cutaneous reactions (apart from transient nausea and vomiting following single low-dose cyclophosphamide treatment). Using STn-conjugated human serum albumin in a solid-phase enzyme-linked immunosorbent assay, it was shown that all patients developed IgM and IgG specific for the synthetic STn hapten. Following immunization, most patients were shown to develop increased titres of complement-mediated cytotoxic antibodies, partially inhibited by synthetic STn hapten, but not by the related TF hapten. We also detected IgM and IgG antibodies reactive with natural STn determinants expressed on ovine submaxillary mucin, the STn specificity of this reactivity being confirmed by hapten inhibition. Evaluation of clinical efficacy in a small pilot study is difficult. Five patients are alive 12 or more months after entry, and another 4 patients are alive 6 or more months after entry into the study. All 3 patients with known widespread bulky disease progressed despite ASI, 2 having died from widespread cancer. Two patients had partial responses, each lasting 6 months. While several patients had disease stability for 3-10 months, 1 patient with pulmonary metastases remains stable 15 months after entry into the program.

Topics: Adjuvants, Immunologic; Antibodies, Neoplasm; Antibody Specificity; Antigens, Tumor-Associated, Carbohydrate; Breast Neoplasms; Carcinoma; Complement System Proteins; Cytotoxicity, Immunologic; Female; Glycoconjugates; Haptens; Humans; Immunization; Ovarian Neoplasms; Tumor Cells, Cultured

The Tn antigen is a neoantigen abnormally expressed in many human carcinomas and expression correlates with metastasis and poor survival. To explore its biomarker potential, new antibodies are needed that specifically recognize this antigen in tumors. Here we generated two recombinant antibodies to the Tn antigen, Remab6 as a chimeric human IgG1 antibody and ReBaGs6 as a murine IgM antibody and characterized their specificities using multiple biochemical and biological approaches. Both Remab6 and ReBaGs6 recognize clustered Tn structures, but most importantly do not recognize glycoforms of human IgA1 that contain potential cross-reactive Tn antigen structures. In flow cytometry and immunofluorescence analyses, Remab6 recognizes human cancer cell lines expressing the Tn antigen, but not their Tn-negative counterparts. In immunohistochemistry (IHC), Remab6 stains many human cancers in tissue array format but rarely stains normal tissues and then mostly intracellularly. We used these antibodies to identify several unique Tn-containing glycoproteins in Tn-positive Colo205 cells, indicating their utility for glycoproteomics in future biomarker studies. Thus, recombinant Remab6 and ReBaGs6 are useful for biochemical characterization of cancer cells and IHC of tumors and represent promising tools for Tn biomarker discovery independently of recognition of IgA1.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Antigens, Tumor-Associated, Carbohydrate; Biomarkers, Tumor; Carcinoma; Female; Glycoproteins; Humans; Immunoglobulin G; Immunoglobulin M; Infant; Male; Mice; Middle Aged; Recombinant Proteins; Tumor Cells, Cultured; Young Adult

Malignant transformation is often associated with abnormal protein glycosylation expressed, amongst others, by the accumulation of simple mucin-type carbohydrates namely Tn and Sialyl-Tn (STn) antigens. These are usually limited in normal tissues and their increased expression has been associated with cancer progression and poor prognosis. This study aims to evaluate the role of Tn and STn antigens in the neoplastic transformation of the canine gastric mucosa and to correlate their putative immunoexpression alterations with some pathological features. Tn and STn antigens expression were immunohistochemically evaluated in canine normal gastric mucosa (n = 3), gastric polyps (n = 9) and gastric carcinomas (n = 25), neoplastic emboli (n = 12) and metastases (n = 8). In normal gastric mucosa, Tn antigen was detected in the gastric epithelial cells, while STn antigen was absent. Similarly, all gastric polyps expressed Tn antigen, but none displayed STn antigen immunostaining. In carcinomas, Tn antigen was expressed in 96% of the cases and STn antigen in 68% of the neoplasms. STn antigen was significantly higher in carcinomas compared with normal mucosa (P < .05). No correlation was found between each antigen and the different subtypes of tumours according to WHO classification, tumour differentiation, lymph vascular invasion or metastasis. All neoplastic emboli expressed both antigens, and the expression score was similar or higher than that displayed by the neoplastic cells of the primary tumour. The high prevalence of STn antigen in gastric carcinomas compared with normal mucosa highlights the cancer-associated nature of this antigen. Our results link STn antigen expression to neoplastic transformation and suggest that it may be a useful marker of gastric cancer progression in dogs.

Topics: Animals; Antigens, Tumor-Associated, Carbohydrate; Biomarkers, Tumor; Carcinoma; Cell Transformation, Neoplastic; Dog Diseases; Dogs; Female; Male; Polyps; Stomach Neoplasms

Due to the fact that many cellular proteins are extensively glycosylated, processing and presentation mechanisms are expected to produce a pool of major histocompatibility complex (MHC) class I-bound protein-derived peptides, part of which retain sugar moieties. The immunogenic properties of the presented glycosylated peptides in comparison to their non-glycosylated counterparts have not been determined clearly. We assessed the cellular immunogenicity of MUC1 (mucin)-derived peptides O-glycosylated with a Tn epitope (GalNAc) using HLA-A*0201 single chain (HHD)-transfected cell lines and transgenic mice. For part of the compounds Tn moiety did not interfere with the HLA-A*0201 binding. Moreover, part of the glycopeptides elicited effective cytotoxic responses, indicating recognition of the glycopeptide-HLA-A*0201 complex by the T cell receptor (TCR) and subsequent cytotoxic T lymphocyte (CTL) activation. The CTLs exhibited a substantial degree of cross-reactivity against target cells loaded with glycosylated and non-glycosylated forms of the same peptide. The studied (glyco)peptides showed cellular immunogenicity in both MUC1-HHD and HHD mice and induced effective lysis of (glyco)peptide-loaded target cells in CTL assays. However, the elicited CTLs did not induce selective lysis of human MUC1-expressing murine cell lines. Moreover, immunization with (glyco)peptide-loaded dendritic cells (DCs) did not induce significant immunotherapeutic effects. We conclude that Tn glycosylated MUC1-derived peptides can be presented by MHC class I molecules, and may be recognized by specific TCR molecules resulting in cytotoxic immune responses. However, the studied glycopeptides did not offer significant benefit as targets for cytotoxic immune response due apparently to (a) cross-reactivity of the elicited CTLs against the glycosylated and non-glycosylated forms of the same peptide and (b) low abundance of glycopeptides on tumour target cells.

Topics: Animals; Antigen-Antibody Reactions; Antigens, Tumor-Associated, Carbohydrate; Carcinoma; Cell Line; Cytotoxicity Tests, Immunologic; Glycopeptides; HLA-A Antigens; Immunization; Immunotherapy; Mice; Mice, Transgenic; Mucin-1; T-Lymphocytes, Cytotoxic; Transfection

We have demonstrated previously that the optimal method for inducing an antibody response against defined cancer antigens is covalent conjugation of the antigen to keyhole limpet hemocyanin (KLH) and use of the potent saponin adjuvant QS-21. Single molecules of glycolipids (tetrasaccharides, pentasaccharides, or hexasaccharides) and MUC1 peptides (containing between one and five MUC1 tandem repeats) conjugated to KLH have proven sufficient for antibody recognition and vaccine construction. However, cancer specificity of monoclonal antibodies against the monosaccharide Tn and disaccharide sTn comes largely from recognition of clusters (c) of these molecules on the cell surface. Tn consists of a monosaccharide (GalNAc) O-linked to serine or threonine on epithelial cancer mucins which are uniquely rich in serines and threonines. We test here several Tn constructs: Tn monosaccharide, Tn(c) prepared on a triple threonine backbone, and Tn prepared on a partially or fully glycosylated MUC1 backbone. We determine that Tn(c) is more effective than Tn, and conjugation to KLH is more effective than conjugation to BSA or polystyrene beads for inducing ELISA reactivity against Tn, and FACS reactivity against Tn-positive tumor cells. Surprisingly, MUC1 glycosylated with Tn at three or five sites per 20 amino acid MUC1 tandem repeat and conjugated to KLH, induced the strongest antibody response against Tn and tumor cells expressing Tn, and had the additional advantage of inducing antibodies against MUC1.

Topics: Animals; Antibodies, Neoplasm; Antigens, Tumor-Associated, Carbohydrate; Cancer Vaccines; Carcinoma; Cell Line, Tumor; Enzyme-Linked Immunosorbent Assay; Female; Flow Cytometry; Hemocyanins; Humans; Mice; Mice, Inbred C57BL; Microspheres; Mucin-1; Vaccines, Conjugate

Tumor-associated antigens are appreciated as diagnostic markers, but they have also prompted tremendous efforts to develop tumor-specific immunotherapy. A previously cloned tumor-associated antigen, EBAG9, was initially defined by reactivity with the monoclonal antibody 22-1-1. Functionally, the EBAG9-encoded gene-product was believed to induce apoptosis in activated immune cells. However, using a cell-biological approach we identified EBAG9 as a Golgi-resident modulator of O-linked glycan expression, the latter product was then recognized by the 22-1-1 antibody. Secondly, EBAG9 expression was found physiologically in all murine tissues examined. This raised the question if EBAG9 is tumor-specific and mediates apoptosis itself or through O-linked glycans generated, among them the cognate 22-1-1 antigen Tn.. We have used immunohistochemistry to detect the expression of 22-1-1 and EBAG9 in various tissues. Correlation between expression of both antigens in cell lines was analysed by immunoblot and flow cytometry. Apoptosis was studied by using flow cytometry and Caspase-Glo 3/7 assay kit. Cellular distribution of EBAG9 was analysed by electron and confocal microscopy.. Here, we compared expression of the 22-1-1 and EBAG9-defined antigens in normal and neoplastic tissues in situ. In contrast to 22-1-1 staining, EBAG9 is a ubiquitously expressed antigen in all normal and cancerous tissues. Functional studies on the role of 22-1-1 reactive material did not support any evidence for apoptosis induction. Employing electron and confocal microscopy, a refined subcellular localization of EBAG9 at the Golgi was obtained.. We suggest that the estrogen-inducible EBAG9 gene-product and the 22-1-1 defined antigen are structurally and functionally separate antigens.

Topics: Adenocarcinoma; Antibodies, Monoclonal; Antigens, Neoplasm; Antigens, Tumor-Associated, Carbohydrate; Antineoplastic Agents; Apoptosis; Biomarkers, Tumor; Brefeldin A; Carcinoma; Carcinoma, Squamous Cell; Caspase 3; Caspase 7; Caspases; Cell Line; Cell Line, Tumor; Cell Nucleus; Colorectal Neoplasms; Flow Cytometry; Golgi Apparatus; Humans; Immunoblotting; Immunohistochemistry; Immunotherapy; Lung Neoplasms; Male; Microscopy, Confocal; Microscopy, Electron; Mouth Neoplasms; Nocodazole; Polysaccharides; Prostatic Neoplasms; Protein Synthesis Inhibitors; Reverse Transcriptase Polymerase Chain Reaction; Stomach Neoplasms; Subcellular Fractions; Tissue Distribution

Glycopeptides containing a tumor-associated carbohydrate antigen (mono-, tri- or hexa-Tn antigen) as a B-cell epitope and a CD4+ T-cell epitope (PV: poliovirus or TT: tetanus toxin) were prepared for immunological studies. Several Tn antigen residues [FmocSer/Thr (alpha-GalNAc)-OH] were successively incorporated into the peptide sequence with unprotected carbohydrate groups. The tri- and hexa-Tn glycopeptides were recognized by MLS128, a Tn-specific monoclonal antibody. The position of the tri-Tn motif in the peptide sequence and the peptide backbone itself do not alter its antigenicity. As demonstrated by both ELISA and FACS analysis, the glycopeptides induced high titers of anti-Tn antibodies in mice, in the absence of a carrier molecule. In addition, the generated antibodies recognized the native Tn antigen on cancer cells. The antibody response obtained with a D-(Tn3)-PV glycopeptide containing three alpha-GalNAc-D-serine residues is similar that obtained with the Tn6-PV glycopeptide. These results demonstrate that short synthetic glycopeptides are able to induce anticancer antibody responses.

Topics: Animals; Antibodies, Neoplasm; Antigens, Tumor-Associated, Carbohydrate; Cancer Vaccines; Carcinoma; Female; Glycopeptides; Mice; Mice, Inbred BALB C

Mucins and simple mucin-type carbohydrates are cancer-associated antigens in several human tumors. Expression of Tn, sialosyl-Tn, Thomsen-Friedenreich (T), sialosyl-T and of a recently identified mucin-like glycoprotein (gp230) has not yet been thoroughly investigated in human cervix carcinogenesis. In the present study sections from normal cervix (n=10), CIN III lesions (n=10), and invasive carcinomas (n=47) were evaluated immunohistochemically using monoclonal antibodies. In normal cervix there was: cytoplasmatic expression of Tn in 1 case (10%); membranous expression of STn in 8 cases (80%); no expression of T and cytoplasmatic expression of ST in 1 case (10%); gp 230 was expressed in all cases with a membranous pattern. In CIN III lesions there was cytoplasmatic and membranous expression of Tn in 3 cases (30%) and of STn in 9 cases (90%); T and ST were not expressed; gp 230 was expressed in 5 cases (50%) both in the cytoplasm and at the cell membrane. In invasive carcinomas we observed Tn expression in 30 cases (63.8%) and STn in 31 cases (66%); T antigen was not expressed; expression of both ST and gp 230 in 24 cases (51.1%); all antigens showed membranous and cytoplasmatic staining. Our results show that Tn and ST are good markers of invasive carcinomas of the human cervix. We have also shown that loss of expression of the mucin-like glycoprotein gp 230 is associated with malignant transformation at a preinvasive stage.

Topics: Antigens, Tumor-Associated, Carbohydrate; Biomarkers, Tumor; Carcinoma; Carcinoma in Situ; Cell Transformation, Neoplastic; Cervix Uteri; Female; Glycoproteins; Humans; Mucins; Neoplasm Invasiveness; Reference Values; Sensitivity and Specificity; Uterine Cervical Dysplasia; Uterine Cervical Neoplasms

The object of this study was the investigation of carbohydrate antigen expression in malignant epithelial cells and benign mesothelial cells in serous effusions from patients diagnosed with epithelial ovarian carcinomas. In addition, to compare antigen expression in carcinoma cells in effusions with those of corresponding primary tumors and metastatic lesions. Sections from 63 malignant effusions from ovarian carcinoma patients and 15 reactive effusions were immunohistochemically stained, using 5 monoclonal antibodies for Lewis(y), Sialyl Lewis(x), Tn, and Sialyl Tn antigens. Tissue sections (n = 97) from corresponding primary ovarian carcinomas and metastatic lesions, as well as from 12 malignant mesotheliomas, were additionally stained using the above panel. Staining for the 4 antigens was seen in carcinoma cells in serous effusions in the majority of cases (range = 71% to 85%). In contrast, immunoreactivity was detected in mesothelial cells in only 6% to 23% of the specimens studied (P < .001 for all 5 markers). With the exception of B3 antibody against Lewis(y) antigen, malignant mesotheliomas stained negative, infrequently showing focal immunoreactivity. An up-regulation of Tn and Sialyl Tn expression was detected in carcinoma cells in effusions when compared with both primary tumors (P < .003 and P < .007, respectively) and metastatic lesions (P < .034 and .041, respectively). Cancer-associated carbohydrate antigens can thus be used as an adjunct in the differentiation between malignant epithelial and reactive mesothelial cells. Ovarian carcinoma cells in effusions show up-regulation of Tn and Sialyl Tn, possibly representing a transient phenotypic alteration facilitating metastasis.

Topics: Antigens, Tumor-Associated, Carbohydrate; Ascitic Fluid; Biomarkers, Tumor; Carcinoma; Exudates and Transudates; Female; Humans; Immunoenzyme Techniques; Lewis Blood Group Antigens; Mesothelioma; Neoplasms, Mesothelial; Ovarian Neoplasms; Pleural Effusion, Malignant; Up-Regulation

Topics: Adenoma; Antibodies, Monoclonal; Antigens, Tumor-Associated, Carbohydrate; Carcinoma; Cell Transformation, Neoplastic; Female; Formaldehyde; Glycosylation; Humans; Immunohistochemistry; Male; Mucins; Paraffin Embedding; Prognosis; Radiotherapy; Retrospective Studies; Salivary Gland Neoplasms; Salivary Glands; Tissue Fixation

T and Tn are pancarcinoma epitopes (EPs) which can be immunodetected in about 90% of adenocarcinomas (CAs). To study the location of T and Tn EPs and their relations to adhesion plaques on CA cells, immunogold-silver staining method was employed at scanning electron microscope (SEM) level. Human breast CA cells grown on coverslips were fixed in paraformaldehyde and glutaraldehyde, reacted with cocktails of monoclonal antibodies against T or Tn EPs, followed by incubation with 10 nm gold conjugated goat anti-mouse immuno-globulins. The positive gold particle labelling was amplified with silver enhancement solution, and the specimens were then routinely critical point dried, sputter-coated with palladium and observed under SEM. The studies show that T and Tn EPs are not randomly distributed on CA cell surface; they are aggregated at the adhesion plaque area. These results confirm that T and Tn EPs play roles in CA cell adhesion, and suggest that they may represent the initial points of contact by immuno-effectors and therefore can be utilized in immunointervention and anti-adhesion therapy against CA.

Topics: Antigens, Tumor-Associated, Carbohydrate; Breast Neoplasms; Carcinoma; Cell Adhesion; Female; Humans; Immunohistochemistry; Microscopy, Electron, Scanning; Tumor Cells, Cultured

Human polyclonal, monospecific anti-T and -Tn antibodies were found to be reactive in ELISA tests with human ovarian (IGROV-1, OVCAR-3 and SKOV-3), breast (SKBr-3 and T47D)- and oral (KB)-carcinoma cell lines, but less so or non-reactive with normal epithelia and fibroblasts. The direct binding radioimmunoassay, using 125I-labeled human antibodies, to the IGROV-1 cancer cells was inhibited by homologous unlabeled antibodies of the same concentration, but not by the respective immunodominant haptenic monosaccharides (Gal for T and GalNAc for Tn). Rodent ascitic monoclonal anti-T (Ca3114 and Ca3741) and anti-Tn (Ca3250, Ca3268 and Ca3638) antibodies were also reactive with the ovarian- and breast-cancer cells, as measured by FACS and ELISA tests, but to a lower extent than the polyclonal human antibodies. Both the monoclonal anti-T (Ca3741) and anti-Tn (Ca3250 and Ca3638) antibody-binding reactivities were significantly inhibited by the haptenic free monosaccharides. Addition of the above MAbs to IGROV-1 ovarian-cancer or T47D breast-cancer cells cultured in vitro resulted in significant cytological change and inhibition of the viability of the tumor cells, but not of normal epithelial breast cells. This effect on viability was shown to be complement-independent, yet it was profoundly influenced by the concentration of the serum added to the assay medium. In vivo biodistribution of the anti-T (Ca3114) and anti-Tn (Ca3638) MAbs administered i.p. to athymic IGROV-1 tumor-bearing CD1 female nude mice revealed higher 125I-labeled antibody accumulation in the tumor xenografts and in their lung tissues, as compared with other organs of the same mice tested. The above results thus suggest the feasibility of utilizing these antibodies in immunotherapy and drug targeting.

Topics: Animals; Antibodies, Monoclonal; Antibody Specificity; Antigens, Tumor-Associated, Carbohydrate; Antigens, Viral, Tumor; Breast Neoplasms; Carcinoma; CCAAT-Enhancer-Binding Proteins; Cell Survival; Coculture Techniques; DNA-Binding Proteins; Dose-Response Relationship, Immunologic; Enzyme-Linked Immunosorbent Assay; Female; Humans; Mice; Mice, Nude; Neoplasm Transplantation; Nuclear Proteins; Ovarian Neoplasms; Tumor Cells, Cultured

Altered glycosylation of mucins leading to the expression of T, Tn, and sialyl-Tn antigens has been shown in ovarian carcinoma, but its relationship with prognosis is still unclear. We investigated immunohistochemically the expression of these antigens in 38 (17 serous and 21 mucinous) ovarian carcinomas to assess their potential prognostic value as compared with stage of disease, histopathology of tumors, and survival time of patients. Eight benign ovarian tumors (four serous and four mucinous), and four normal ovarian tissues also were studied. Of the 38 carcinomas, 25 (66%) expressed T, 27 (71%) expressed Tn, and 33 (87%) expressed sialyl-Tn antigens. Most cases (83%) expressed two or all of the three types of antigens simultaneously. Normal ovarian epithelia showed no staining for these antigens, and benign ovarian tumors were either negative or occasionally expressed weak staining in less than 25% of epithelial cell areas. Statistical analyses showed strong associations between Tn and sialyl-Tn antigen expressions and disease stage as well as histological grade. In 19 ovarian carcinoma patients with available survival data, the overall survival times of patients with high Tn or sialyl-Tn antigen expression were significantly worse than those of the patients with negative and low expression (P < .05 and P < .01). In multivariate stepwise regression analysis, disease stage (P = .000) and Tn antigen expression (P = .02) were found to be significant independent parameters associated with the overall survival time. These findings suggest that, with exception of T antigen expression, the expression of Tn and sialyl-Tn antigens in ovarian carcinomas may provide additional prognostic information on patient outcome.

Topics: Antigens, Tumor-Associated, Carbohydrate; Biomarkers, Tumor; Carcinoma; Female; Humans; Immunohistochemistry; Ovarian Neoplasms; Prognosis; Survival Rate

We report here the first amino acid sequence of an anti-Tn monoclonal antibody raised against human breast cancer cells and show that a single chain Fv fragment of this IgM retains the Tn-binding specificity as defined by functional assays with asialo-OSM and membrane extracts from MCF-7 cells. Sequence comparisons and molecular modeling of 83D4 indicate that the antibody combining site displays a cavity-like feature primarily defined by the CDR H1 and H2 loops. This pocket could accommodate a single Tn molecule, thus, suggesting a structural explanation for the predominant expression of a particular VH gene segment in a group of antibodies that recognize tumor-associated antigens arising from an aberrant O-glycosylation.

Topics: Amino Acid Sequence; Animals; Antibodies, Monoclonal; Antibodies, Neoplasm; Antibody Specificity; Antigens, Tumor-Associated, Carbohydrate; Base Sequence; Breast Neoplasms; Carcinoma; Cloning, Molecular; Gene Amplification; Humans; Hybridomas; Immunoglobulin Fragments; Immunoglobulin kappa-Chains; Immunoglobulin M; Immunoglobulin Variable Region; Mice; Models, Molecular; Molecular Sequence Data; Recombinant Fusion Proteins; Sequence Alignment; Sequence Analysis, DNA; Tumor Cells, Cultured

Epithelial mucins are present at the apical membranes of gastrointestinal epithelial cells or in their secretions. In this study, we examined the occurrence of peptide epitopes of the mucins MUC1 and MUC3 and of three mucin-associated glycotopes (TF, Tn, and s-Tn) in a series of colorectal tissue samples (normal colon, adenomas with different grades of dysplasia, carcinoma in situ, and invasive carcinomas). A new monoclonal antibody to a conformation-dependent peptide epitope of MUC1 was employed, which does not react with the fully glycosylated mucin as found in normal gastrointestinal mucosa. We found that adenomas acquired the ability to expose Tn, s-Tn, TF and MUC1 epitopes, and this correlated with increasing malignant potential. The secretory mucin, MUC3, revealed a different pattern: it was detectable in all sections, with maximum expression in adenomas and decrease in carcinomas. Most importantly, normal mucosa and benign lesions showed supra-nuclear and/or apical distribution of these antigens, but malignant lesions and lesions with a very high risk of malignancy revealed diffuse cytoplasmic and basolateral membrane localization. The immunohistological response to a combination of MUC1-related antibodies may assist in assessing the malignant potential and status of lesions of the colon.

Topics: Adenoma; Antigens, Tumor-Associated, Carbohydrate; Biomarkers, Tumor; Carcinoma; Cell Membrane; Cell Transformation, Neoplastic; Colonic Neoplasms; Cytoplasm; Humans; Immunohistochemistry; Intestinal Mucosa; Intracellular Membranes; Mucin-1; Mucin-3; Mucins; Precancerous Conditions

The expression of simple mucin-type carbohydrate antigens, Tn and sialyl-Tn antigens, was evaluated by immunohistochemical staining with monoclonal antibodies in normal squamous epithelium, dysplasia, carcinoma in situ, and invasive squamous cell carcinoma of the uterine cervix. The expression of the Tn antigen detected by HB-Tn1 and B1.1 was found in 17 (20%) and 19 (23%) of the 83 invasive carcinomas, respectively, but was not found in the 36 normal squamous epithelia, 22 severe dysplasias, or 24 carcinomas in situ. The sialyl-Tn antigen was detected by HB-STn1 and TKH-2 in 14 (64%) and 11 (50%) of the 22 severe dysplasias, 13 (54%) and 10 (42%) of the 24 carcinomas in situ and 48 (58%) and 42 (51%) of the 83 invasive carcinomas, respectively, but was completely absent in 36 normal squamous epithelia. Coexpression of the sialyl-Tn antigen was observed in 89% of the cases expressing the Tn antigen. No significant difference was observed between the immunoreactivities of the antigens in the metastatic lymph nodes and primary tumors. No correlation was found between the expression of each antigen and clinical state, histologic type, depth of invasion, parametrial spread, lymphatic and vessel permeation, lymph node metastasis, or 5-year survival rate. The expression of Tn and sialyl-Tn demonstrates a specific change in the neoplastic progression from carcinoma in situ to invasive carcinoma and from normal to dysplasia, respectively, in squamous cell neoplastic lesions of the cervix. Tn and sialyl-Tn antigens may be useful markers for biologic investigation of neoplastic transformation in cervical squamous cell carcinoma.

Topics: Antigens, Tumor-Associated, Carbohydrate; Biomarkers, Tumor; Carcinoma; Epithelium; Female; Humans; Neoplasm Metastasis; Uterine Cervical Neoplasms; Uterus

The simple mucin-type carbohydrate antigens Tn, sialosyl-Tn, T and the 'cryptic' sialylated variant of the last represent the mucin core oligosaccharide structures that are produced in the initial steps of the mucin biosynthetic pathway. Utilizing monoclonal antibodies anti-Tn antigen (HB-Tn1), anti-sialosyl-Tn antigen (HB-STn1), anti-T antigen (HB-T1) and the biotinylated Amaranthus caudatus agglutinin (ACA), we have investigated the expression of the simple mucin-type carbohydrate antigens in hereditary nonpolyposis colorectal cancer (HNPCC; 15 cases) compared with sporadic colorectal cancer (CRC; 60 cases) and normal colonic mucosa (30 cases). A variable positivity of Tn, sialosyl-Tn, T and the cryptic sialylated form of this latter antigen was encountered in both HNPCC and sporadic CRC cases; in addition, in normal colonic mucosa a constant reactivity was encountered only for Tn and the cryptic sialylated form of T, while negative results were always obtained for sialosyl-Tn and T antigens. Statistical analysis, performed using a Chi-square test, showed significantly lower (P = 0.037) expression of sialosyl-Tn and higher (P = 0.022) expression of T in HNPCC than in sporadic CRC, suggesting a greater presence of beta 1,3 galactosyltransferase activity in HNPCC than in sporadic CRC. We were unable to identify a peculiar phenotype for HNPCC with simultaneous evaluation of reactivity for HB-Tn1, HB-STn1, HB-T1 and ACA; the biological significance of the preferential expression of T antigen in HNPCC remains to be investigated.

Topics: Adult; Aged; Antibodies, Monoclonal; Antigens, Tumor-Associated, Carbohydrate; Antigens, Viral, Tumor; Carcinoma; Colorectal Neoplasms; Female; Humans; Intestinal Mucosa; Male; Middle Aged; Reference Values

The goal of this study was to determine if polypeptides that bind specifically to the carcinoma-associated Thomsen-Friedenreich (T) antigen could be isolated from a random peptide bacteriophage display library. T antigen is a carbohydrate antigen that is exposed and immunoreactive on the surfaces of most primary carcinomas and their metastases, while it is masked on normal cells. Tumor-specific surface carbohydrates are often used as markers of cell differentiation and play a role in cell aggregation, which is an important step in the metastatic process. Therefore, peptides that bind and mask T antigen may yield useful carbohydrate-specific probes and provide insight into carbohydrate-mediated tumor-cell aggregation. A 15-amino acid random peptide bacteriophage display library was screened for polypeptides that exhibited high specificity to two glycoproteins which display T antigen on their surfaces. The results suggest that synthetic peptides identified from the bacteriophage display library have high affinities (Kd approximately 1 microM) and specificities for proteins and human tumor cells which present T antigen. Thus, random bacteriophage peptide display libraries may be a rich source of sequences that bind to carbohydrate antigen structures.

Topics: Amino Acid Sequence; Animals; Antigens, Tumor-Associated, Carbohydrate; Carcinoma; Colonic Neoplasms; Enzyme-Linked Immunosorbent Assay; Fluorescent Dyes; Humans; Inoviridae; Melanoma; Mice; Molecular Sequence Data; Peptide Library; Peptides; Tumor Cells, Cultured

Pathogenetic aspects of pancarcinoma T/Tn autoantigens were investigated; they are present in approximately 90% of all carcinomas from incipience and throughout. T/Tn are occluded in noncarcinoma (non-CA) diseased and healthy tissues. By serological and immunohistochemical methods, we found that well-differentiated carcinomata express a higher proportion of T than Tn, while in poorly differentiated carcinomata, Tn predominates over T. Tn density of primary carcinomas correlates positively with aggressiveness, early clinical relapse, and early death. Delayed-type skin hypersensitivity to T (DTHR-T) and solid-phase anti-T antibody immunoassay (SPIA-T), respectively, detected 85% of 461 and 88% of 222 carcinoma patients; < 7% of over 450 benign diseased and healthy subjects reacted positively in these assays. T/anti-T assays are highly effective in detecting incipient (TisN0M0 and T1N0M0) carcinomas: DTHR-T-85% of 41, and SPIA-T-96% of 26 patients. Positive anti-T tests predicted CA in 74% of 47 patients months to years before their biopsy/X-ray turned positive.

Topics: Adenocarcinoma; Antibodies; Antigens, Neoplasm; Antigens, Tumor-Associated, Carbohydrate; Autoantigens; Breast Neoplasms; Carcinoma; Carcinoma, Ductal, Breast; Case-Control Studies; Cohort Studies; Humans; Immunoglobulin M; Isoantigens; Prognosis

Using immunohistochemical techniques and whole-cell enzyme-linked immunosorbent assay, we have determined that monoclonal antibodies (mAbs) B72.3 and CC49, which are widely used in the diagnosis and treatment of several human epithelial cancers, are expressed in a transplantable rat colon carcinoma cell line, K12-TRb. MAbs B72.3 and CC49 react with tumor-associated glycoprotein-72 (TAG-72) which is a carcinoma mucin molecule expressed in colon, breast, pancreatic, ovarian, lung, and gastric cancers. The carbohydrate epitope for mAb B72.3 is sialylated Tn (sTn), whereas CC49 reacts with an unknown carbohydrate epitope. K12-TRb is a transplantable rat colon carcinoma cell line derived from a dimethylhydrazine tumor which grows as progressive tumors in syngeneic BD IX rats. We found that the carbohydrate epitopes for mAbs B72.3 and CC49, including sTn, were more tumor-restricted in the rat than in humans. The only binding these had mAbs to normal rat tissue was to small-intestinal mucosa. MAbs B72.3 and CC49 were radiolabeled with iodine-125 (125I) and injected intravenously into BD IX rats containing subcutaneously grown syngeneic K12-TRb tumors. Biodistribution experiments were conducted by dissecting groups of three rats on days 2, 4, 7, and 14 after injection of radiolabeled mAbs. These experiments confirmed that maBs B72.3 and CC49 localize to K12-TRb tumors in vivo, and that the higher affinity mAb CC49 localized better than mAb B72.3. Gamma-camera imaging of subcutaneous K12-TRb tumors was successfully performed using 125I-labeled mAb CC49. The importance of this model is that mAbs B72.3 and CC49, immunoconjugates of these mAbs, and vaccines containing their corresponding carbohydrate epitopes, including sTn, can be studied in a relevant immunocompetent syngeneic rat colon carcinoma model.

Topics: Animals; Antibodies, Monoclonal; Antigens, Tumor-Associated, Carbohydrate; Carcinoma; Colonic Neoplasms; Enzyme-Linked Immunosorbent Assay; Epitopes; Female; Humans; Immunohistochemistry; Mice; Mucins; Neoplasms, Experimental; Radionuclide Imaging; Rats; Rats, Inbred Strains; Sialoglycoproteins; Transplantation, Isogeneic

Topics: Antigens, Tumor-Associated, Carbohydrate; Biopsy; Breast Neoplasms; Carcinoma; Humans; Immunotherapy, Active; Time Factors

Topics: Adenocarcinoma; Agglutination Tests; Antibodies; Antibody Specificity; Antigens, Neoplasm; Antigens, Tumor-Associated, Carbohydrate; Breast Neoplasms; Carcinoma; Carcinoma, Intraductal, Noninfiltrating; Cell Line; Cell Migration Inhibition; Cytotoxicity, Immunologic; Disaccharides; Epitopes; Erythrocytes; Female; Humans; Hypersensitivity, Delayed; Killer Cells, Natural; Leukocytes; Skin Tests

Tn antigen is the immediate precursor of the carcinoma (CA)-associated T antigen; both are masked in non-CA tissues. Tn antigen was detected by absorption of human anti-Tn antibody in 46 of 50 primary breast CAs and in all 6 metastases originating from Tn-positive primary CAs. Thirteen of 25 (52%) anaplastic CAs, but only 2 of 15 (13%) well differentiated CAs had more Tn than T; 1 anaplastic CA had neither antigen. Eighteen of 20 benign breast lesions had no Tn; the 2 positive lesions were premalignant. All 19 breast CAs, studied immunohistochemically, reacted strongly with human polyclonal anti-Tn; benign or normal glandular tissues had minimal or no reactivity. Among live cancer cell lines, the most malignant sublines had more Tn than T on their cell surfaces. Preliminary studies with rodent monoclonal anti-Tn and anti-T antibodies gave immunohistochemical reactivity patterns similar to those of the polyclonal antibodies, but the former were less sensitive in absorption tests. Tn is a CA marker that promises to be useful in tumor detection.

Topics: Animals; Antibodies, Monoclonal; Antigen-Antibody Reactions; Antigens, Neoplasm; Antigens, Tumor-Associated, Carbohydrate; Antigens, Viral, Tumor; Blood Group Antigens; Breast Neoplasms; Carcinoma; Carcinoma, Intraductal, Noninfiltrating; Cell Line; Female; Hemagglutination Tests; Histocytochemistry; Humans; Immunochemistry; Immunosorbent Techniques; Lymphoma; Mammary Neoplasms, Experimental; Mice; Neoplasm Metastasis; Neoplasm Recurrence, Local; Rats

Topics: Animals; Antigens, Neoplasm; Antigens, Tumor-Associated, Carbohydrate; Breast Neoplasms; Carcinoma; Female; Humans; Mammary Neoplasms, Experimental; Rats