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T F Orntoft

Publications and source records attributed to T F Orntoft.

At least 73 records · Page 4Linked to original sources
PubMed1991

Frequency and mechanism of Lewis antigen expression in human urinary bladder and colon carcinoma patients.

Changes in the expression of Lewis antigens have been associated with cancer diseases, and recent results have pointed at a possible increased risk of cancer development among Lewis negative patients. The frequency of the erythrocyte Lewis phenotypes Le(a- b+), Le(a+ b-) and Le(a- b-) was analysed in patients suffering from urinary bladder cancer (82), colon cancer (21), and benign urological diseases (45). An increased frequency of Lewis negative individuals was found among colon cancer patients (P less than 0.004) and bladder cancer patients (P = 0.05). The Lewis negative phenotype was shown to be associated with unfavourable disease parameters: invasion (P less than 0.02) and high grade of atypia (P less than 0.01) in bladder cancer patients, and high Dukes stage (P less than 0.05) in colon cancer patients. alpha 1-4fucosyltransferase activity (Lewis transferase) was shown to be present in saliva from four out of eight erythrocyte Lewis negative cancer patients, indicating that some patients with advanced cancer disease may have converted from a Lewis positive to a Lewis negative phenotype.

ABO Blood-Group System↗
PubMed1991

Lewis antigen expression in benign and malignant tissues from RBC Le(a-b-) cancer patients.

Eight red blood cell (RBC) Le(a-b-) individuals were selected from a series of patients with bladder or colon cancer. Defined by the presence or absence of alpha 1-4-L-fucosyltransferase activity in saliva, four of these patients were characterized as non-genuine Lewis negative [RBC Le(a-b-) with alpha 1-4-L-fucosyltransferase activity in saliva], and four as genuine Lewis negative [RBC Le(a-b-) with no alpha 1-4-L-fucosyltransferase activity in saliva]. Stainings of paraffin embedded formalin fixed tissue sections for Lea and Leb antigens were performed by means of an indirect immunohistochemical method on all malignant and benign tissue previously removed from these eight patients. Leb antigens were always expressed independently of both the Lewis and the secretor status of the individual. Lea antigens, on the other hand, showed a different staining pattern. Although primarily expressed in non-genuine Le(a-b-) individuals, Lea antigens were expressed in genuine Le(a-b-) individuals as well--to a limited extent, but still detectable. Thus, these findings seem to show that the Lewis antigen expression is tissue dependent, and it is not possible to predict tissue Lewis antigen expression by merely examining erythrocytes or saliva.

ABO Blood-Group System↗
PubMed1991

Lewis blood group antigens in salivary glands and stratified epithelium: lack of regulation of Lewis antigen expression in ductal and buccal mucosal lining epithelia.

The expression of Lewis antigens is thought to be controlled by the Secretor and Lewis genes. While secretor status is known to regulate the expression of ABH antigens in many tissues, few studies have attempted to correlate Lewis antigen expression on erythrocytes and saliva with that of epithelial tissues. We examined the expression of Lewis a and b and related antigens in human epithelium of minor salivary glands and labial nonkeratinized oral mucosae from 16 individuals by immunohistology using monoclonal antibodies. The expression of these antigens, as detected by monoclonal antibodies (MAbs) used, was correlated with erythrocyte phenotype and saliva secretor status. In acinar cells of glands, Leb antigen was expressed only in secretors, and Lea only in nonsecretors. However, in gland ducts and oral mucosae, Leb was found in both secretors and nonsecretors, as well as in 2 cases of Lea-b-, secretors. Thus, antigen expression in acinar cells of minor salivary glands was correlated with the predicted genotypes, whereas inappropriate expression of Leb antigen was found in epithelial cells of gland ducts and oral mucosae. The present data indicate that the Lewis blood group phenotype is regulated differently in duct cells and stratified epithelium than in saliva and erythrocytes.

Carbohydrate Sequence↗
PubMed1991

Cellular localization of PNA binding in colorectal adenomas: comparison with differentiation, nuclear:cell height ratio and effect of desialylation.

The lectin Arachis Hypogaea (Peanut Agglutinin, PNA) was used to study the cellular localization of the Thomsen-Friedenreich (T) disaccharide Gal-beta (1-3)-GalNAc alpha 1-R in 22 formalin-fixed paraplast-embedded colorectal adenomas of varying cellular dysplasia. An indirect immunoperoxidase method was used prior to and after neuraminidase treatment. Detailed information on the cellular localization of PNA binding was obtained. In addition, morphometric measurements of the nuclear: cell height ratios were performed on staining-filtered micrographs of crypts from all adenomas. We found 1) a statistically significant increase in the nuclear:cell height ratio with increasing grade of dedifferentiation (p less than 0.003), 2) a statistically significant smaller nuclear:cell height ratio in crypts that were PNA-positive in the Golgi region when these were compared to crypts that were PNA-positive on luminal cell membranes, 3) a decreasing number of crypts expressing PNA binding sites in the Golgi region with increasing dedifferentiation, leading to complete absence of PNA binding sites in Grade IV adenomas, 4) neuraminidase pretreatment increased the number of crypts expressing PNA binding sites in cytoplasm and on luminal membranes, whereas no changes were detected in crypts expressing PNA binding sites in the Golgi region. Our results confirm the general concept of accumulation of precursors of carbohydrate antigens in dedifferentiated cells. On the basis of the results presented, we conclude that the nuclear:cell height ratio shows a good correlation with the cellular localization of PNA binding, cellular differentiation and classic pathologic grading.

Adenoma↗
PubMed1991

Regulation of the oncodevelopmental expression of type 1 chain ABH and Lewis(b) blood group antigens in human colon by alpha-2-L-fucosylation.

Blood group antigen expression in the distal human colon is related to the development of the organ and is modified by malignant transformation. To elucidate the biochemical basis for these changes, we have (a) analysed the activity of glycosyltransferases coded for by the H, Se, Le, X, and A genes, in tissue biopsy specimens from normal and malignant proximal and distal human colon; (b) characterised the glycosphingolipids expressed in the various regions of normal and malignant colon by immunostaining of high performance thin layer chromatography plates; and (c) located the antigens on tissue sections from the same subjects by immunohistochemistry. In both secretors and non-secretors we found a significantly higher activity of alpha-2-L-fucosyltransferases in carcinomatous rectal tissue than in tissue from normal subjects, whereas the other transferase activities studied showed no significant differences. The acceptor substrate specificity suggested that both the Se and the H gene dependent alpha-2-L-fucosyltransferases are increased in carcinomas. In non-malignant tissue the only enzyme which showed appreciably higher activity in caecum than in rectum was alpha-2-L-fucosyltransferase. Immunochemistry and immunohistochemistry showed alpha-2-L-fucosylated structures in normal caecum from secretors and in tumour tissue from both secretors and non-secretors. We conclude that the alpha-2-L-fucosyltransferases control the expression of ABH, and Lewis(b) structures in normal and malignant colon.

ABO Blood-Group System↗
PubMed1990

O-linked mucin-type glycoproteins in normal and malignant colon mucosa: lack of T-antigen expression and accumulation of Tn and sialosyl-Tn antigens in carcinomas.

The expression of carbohydrate core-structures on O-linked glycoproteins was examined in fetal (n = 6), infantile (n = 2), normal adult (n = 15), and malignant (n = 22) colorectal tissue by means of monoclonal antibodies (MAbs) specific for Tn (GalNAc alpha 1-O-R), sialosyl-Tn (NeuAc alpha 2-6GalNAc alpha 1-O-R), and T (Gal beta 1-3GalNAc alpha 1-O-R) antigens. Immunolabelling of solubilized malignant tissue, separated by SDS-PAGE, showed expression of Tn and sialosyl-Tn antigens on 3 molecules of similar mw (230, 210, and 170 kDa), whereas no T antigens could be detected. Immunohistochemical techniques showed that fetal colon mucosa expressed Tn antigens but no sialosyl-Tn antigens. Infantile colon mucosa, however, expressed Tn as well as sialosyl-Tn antigens, and normal adult colon mucosa cells expressed no Tn antigens but sialosyl-Tn in 2 out of 6 biopsies from cecum, which indicates occurrence post partum of alpha-6-NeuAc-transferase. Endothelium in normal adult mucosa showed expression of both Tn and sialosyl-Tn antigens; 82% of carcinoma tissue sections expressed Tn antigens, and 73% expressed sialosyl-Tn antigens in mucin or cytoplasm, or on luminal cell membranes. T antigens could be detected neither in normal mucosa cells at any stage of development, nor in carcinomas. The possibility exists that this could be due to masking of T antigen. Mucin-type blood-group A antigens which contain an internal T-disaccharide were demonstrated in 4 out of 4 A1 tumors by means of MAb HH5. However, urea-containing SDS-PAGE analysis demonstrated an HH5 binding to molecules different from those binding anti-Tn. In remote morphologically normal and abnormal crypts in colons from carcinoma patients, both Tn and sialosyl-Tn antigens were expressed in secreted mucin in 40% of the cases. The data indicate an expression of O-linked Tn and sialosyl-Tn core structures in fetal and infantile colon and in colorectal carcinomas.

Antibodies, Monoclonal↗
PubMed1990

Murine monoclonal antibodies directed to the human histo-blood group A transferase (UDP-GalNAc:Fuc alpha 1----2Gal alpha 1----3-N-acetylgalactosaminyltransferase) and the presence therein of N-linked histo-blood group A determinant.

Mouse MAbs (WKH-1 through -3) to the human histo-blood group A glycosyltransferase (Fuc alpha 1----2Gal alpha 1----3 galactosaminyltransferase) were established by immunization with the purified native A transferase protein. Hybridomas were selected on the basis of solid-phase reactivity with the purified native A transferase, cell immunofluorescence and immunoprecipitation of transferase activity, and absence of reactivity with blood group ABH carbohydrate determinants. Three MAbs, thus selected, were found most likely to react with the protein epitopes unrelated to carbohydrate epitopes of purified A transferase. The MAbs reacted with cells having high A transferase activity and immunoprecipitated the A transferase activity as well as the 40,000 MW iodinated transferase protein. The antibodies were shown, however, to immunoprecipitate and partially inhibit not only A1 and A2 but also B transferase activity from plasma and A transferase from human lung, and to react with B cells expressing B transferase, thus indicating a cross-reactivity with B transferase. In contrast, they showed no reactivity with various cells having the O phenotype and did not immunoprecipitate the A transferase from porcine submaxillary glands or the alpha 1----2fucosyltransferase from Colo205 cells. The purified A glycosyltransferase was found to carry blood group A carbohydrate determinants by immunochemical detection with a panel of anti-carbohydrate MAbs. These determinants are believed to be N-linked, since treatment of the purified A transferase with N-glycanase removed activity. Immunohistological studies of three epithelial tissues showed that the antibodies stained the Golgi area of cells in epithelia from A and B, but not O, individuals.

ABO Blood-Group System↗
PubMed1990

Profiles of Lewisx-containing glycoproteins and glycolipids in sera of patients with adenocarcinoma.

Oligosaccharides with Lex determinant (Gal beta 1----4[Fuc alpha 1----3]GlcNAc) are accumulated in large quantities in various adenocarcinomas. Monoclonal antibodies recognizing mono-, di-, or trimeric Lex showed a preferential staining of specific stages of human fetal tissues and various human adenocarcinomas. Thus, these carbohydrate epitopes are typical of oncodevelopmental antigens. The present study investigated the presence of Lex epitope in sera of normal individuals and cancer patients, utilizing two high-affinity monoclonal antibodies, SH1 and SH2, directed to mono- and dimeric Lex structures, respectively. The Lex antigen in serum was eluted in the void volume fraction of a gel filtration column, determined by using monoclonal antibody SH1, and found to be carried on a glycoprotein with a molecular weight of approximately 200,000. The Lex antigen was present in the void volume fraction of the majority (85%) of sera from adenocarcinoma patients. Although the Lex epitope was also detected in a smaller proportion (33%) of normal sera, its levels were significantly lower than in cancer sera. Lex antigen was also detected in serum glycolipid fraction; however, no significant differences were observed in normal and cancer sera. A double determinant solid phase immunoassay utilizing SH2 as the capture antibody and SH1 as the detecting antibody allowed direct determination of Lex levels in sera. By the use of this direct assay, the levels of serum Lex were found to increase in association with the progression of colorectal cancer (Dukes A to D). The percentage of detectability in sera from colon cancer patients was as follows: Dukes A, 20%; Dukes B, 45%; Dukes C, 67%; and Dukes D, 74%. The levels of serum Lex were also of prognostic value in Dukes C cancer patients after surgery and during postoperative follow-up.

Adenocarcinoma↗
PubMed1989

Binding of wheat and peanut lectins to human transitional cell carcinomas. Correlation with histopathologic grade, invasion, and DNA ploidy.

The binding of peanut (PNA) and wheat germ (WGA) lectins to tissue sections was examined in biopsy specimens from normal urothelium (ten patients) and from tumor tissue of noninvasive (17 patients) and invasive bladder (31 patients) carcinomas. The results were correlated to DNA content, histopathologic grade, and the presence or absence of invasion. Significant alterations in lectin binding associated with the development of cancer were found. A gradual loss of both PNA and WGA binding was found to correlate with higher grades of atypia (P less than 0.001). The loss of WGA binding was significantly correlated with both tumor aneuploidy (P less than 0.001) and the presence of invasion (P less than 0.05), whereas no significant correlation was found between loss of PNA binding and these variables. We concluded that the loss of WGA binding structures associated with bladder cancer shows a better correlation with known risk factors (aneuploidy and invasion) than the loss of PNA binding does.

Arachis↗
PubMed1989

Blood group ABH-related antigens in normal and malignant bladder urothelium: possible structural basis for the deletion of type-2 chain ABH antigens in invasive carcinomas.

A complete panel of mouse monoclonal antibodies (MAbs) against Type-2 chain (GaI beta I-4GlcNAc-R) blood-group antigens (N-acetyl-lactosamine, Lex, H, Ley, A monofucosylated, Aley, repetitive A) was used in a detailed immunohistological study of the modulation of these carbohydrate antigens in transitional-cell carcinomas. The histological and cellular locations of these antigens were studied in 19 normal bladder biopsies and 53 transitional-cell carcinomas with as well as without neuraminidase treatment of tissue sections in order to uncover potential sialylated antigens. The antigen expression was correlated to individual A1A2BO, Lewis, and secretor status. Several alterations of blood group expression were found: (1) loss of A and H antigens with accumulation of Ley antigens; (2) loss of correlation between antigen expression and secretor status; (3) disruption of the orderly stratification of blood-group antigen expression in relation to cell layers; and (4) changes in subcellular location of antigen expression. The present data indicate that deletion of Type-2 chain ABH antigens in transitional-cell carcinomas is associated with alpha 1-3 fucosylation of the H antigen leading to accumulation of Ley antigens.

ABO Blood-Group System↗
PubMed1989

Immunohistochemistry and cytochemistry of experimental rat bladder cancer: binding of the lectins PNA and WGA and of a Le(Y) mouse monoclonal antibody.

Two lectins, peanut agglutinin (PNA) and wheat germ agglutinin (WGA), and a mouse monoclonal antibody against blood group Le(Y) were used to study the distribution of carbohydrate antigens in an experimental rat bladder cancer model. Neoplasia was induced in 28 rats by intravesical installation of N-nitroso-N-methyl-urea (NMU). Fifteen rats were installed with the NMU solvent and served as controls. Urothelial samples were taken from all animals, the atypia were graded and detailed data on the location of the lectin-binding structures and the binding of the monoclonal antibody were obtained by immunohistochemical methods. Urine samples were collected at different times during tumor development and data on the cytological location of the lectin-binding structures and the binding of the monoclonal antibody were obtained by immunocytochemical methods. Examination of the histological distribution of lectin binding structures and Le(Y) antigen showed a characteristic change in carbohydrate antigen expression associated with the development of urothelial atypia. In normal urothelium carbohydrate antigens were present in cytoplasm, whereas they became expressed on cell membranes in non-invasive carcinomas. Immunocytochemistry of urine specimens revealed a lack of correlation between the antigen expression found in exfoliated cells and that found in tissue. Morphologically normal cells from NMU-treated animals were found to express a carcinoma associated antigen pattern.

Animals↗
PubMed1989

Lectinohistochemistry of human bladder cancer: loss of lectin binding structures in invasive carcinomas.

With the purpose of studying changes in the expression of glycoconjugate structures in urothelium, nine different lectins (PNA, WGA, VFA, GSA II, STA, UEA I, LCA, DBA and HPA) with specificity for mono- or oligo-saccharides were used on formalin-fixed, paraffin-embedded tissue sections from 47 patients who had undergone surgical resection for bladder tumors and on normal urothelial biopsies from 10 patients. The tumors were graded and a lectinohistochemical method using biotinylated lectins and avidin-biotin-peroxidase complex was used to demonstrate the lectin binding. Positive staining reactions of cells in cytoplasm and on membranes were evaluated in the basal, the intermediate, and the luminal cell layers, respectively. In both normal and atypical urothelium lectin binding predominated in the luminal cell layer and decreased towards the basal cell layer. In normal urothelium all lectins stained greater than 66% of the cells in the luminal cell layer in cytoplasm and between 5 and 100% of the cells on membranes depending on the lectin used. A gradual loss of lectin-binding structures was seen with increasing grade of atypia. The range of this decrease varied considerably from one lectin to another, but it was consistently found that the percentage of cells stained in cytoplasm and on membranes decreased. A significantly lower percentage of cells stained in cytoplasm was found in invasive tumor cell-islands compared to normal urothelium. In invasive tumor cell-islands staining of cells on membranes was completely absent, except for HPA lectin that stained less than 10% of the cells. In conclusion, we demonstrate a dramatic decrease in lectin-binding carbohydrate structures associated with urothelial malignant progression.

Carcinoma, Transitional Cell↗
PubMed1989

Heterogeneic expression of blood group A and H isoantigens in bladder tumors: association with nuclear volume.

Intratumor heterogeneity is a major problem in immunodiagnosis and treatment of carcinomas. To elucidate the well-known heterogeneity in transitional-cell carcinomas of the ability to express blood group ABO isoantigens, a stereological estimate of the mean nuclear volume in areas expressing blood group antigens was compared to the estimate from areas of identical pathological grade at which antigen expression was deleted. Four microscopic fields were examined from antigen-positive and four from antigen-negative areas in sections from 21 blood group O and 20 blood group A individuals. The sections were stained before examination by an indirect peroxidase method using monoclonal anti-H and anti-A antibodies. The mean nuclear volume increased, as expected, with increasing pathological grade. In blood group O individuals the mean nuclear volume was 241.5 microns 3 in antigen-positive areas and 338.2 microns 3 in antigen-negative areas (2p less than 0.0005) of identical pathological grade. In group A individuals the mean nuclear volume was 217.1 microns 3 in positive areas and 351.1 microns 3 in corresponding negative areas (2p less than 0.0025). The variation in volume parameter was essentially caused by a true variation between tumors (greater than 82%). The results indicate a complex biological mechanism associated with the cellular ability to express blood group antigens.

ABO Blood-Group System↗
PubMed1989

Loss of blood group ABO-related antigen expression in urothelium from patients with chronic cystitis.

A panel of mouse monoclonal antibodies was used to determine the expression of blood group ABH-related antigens carried by type 1 chain (H, Lea, Leb, ALed, ALeb) and type 2 chain (N-acetyllactosamine, H, Lex, Ley, A/ALey) core structures in biopsies of urothelium from patients with chronic cystitis. The biopsies originated from 17 individuals (9 A1, 7 H, 1 B) who had Le(a-b+) erythrocytes, and who were saliva secretors. Microscopic examination showed a variable extent of edema, hyperemia, bleeding, and infiltration. The expression of blood group antigens was determined in the 3 cell layers of urothelium by an indirect peroxidase method and compared with previous results from normal urothelium. Type 1 and type 2 chain A antigens and type 1 chain H antigens were deleted from urothelium in a significant (p less than 0.05) number of patients with chronic cystitis, and Lea (partly sialylated) expression was extended from the luminal cell layer to all cell layers. Antigen expression was independent of the presence or absence of polymorphonuclear cells in the infiltrate. In the basal cell layer of 44% of patients with chronic cystitis total deletion of type 1 and type 2 chain antigen expression was dominating. Both type 1 and type 2 chain antigens gradually appeared toward the luminal cell layer. The findings are parallel to some of those observed in transitional cell carcinomas, and should be taken into consideration when evaluating ABH deletion in carcinomas.

ABO Blood-Group System↗
PubMed1989

DNA replication in experimental rat bladder tumours: immunohistochemical detection of bromodeoxyuridine labelled nuclei.

With the purpose of studying DNA replication activity and location in normal and malignant tissue, bladder tumours were induced in ten rats by the intravesical installation of N-Nitroso-N-Methyl-Urea. Ten rats were installed with the NMU solvent and served as controls. The animals were injected intraperitoneally with 1 mg bromodeoxyuridine/100 g weight one hour prior to sacrifice. An indirect immunoperoxidase method using mouse monoclonal anti-bromodeoxy-uridine antibody was used on tissue sections of normal urothelium and bladder tumours to visualize labelled nuclei. Labelling indices were calculated and correlated to the grade of atypia. We found that normal urothelium had very little proliferative activity. The labelling index of tumours increased with increasing grade of atypia, being highest in invasive tumours. Only cells located to the basal cell layer were labelled in normal and grade I urothelium. In grade II and III tumours labelled cells were found in the intermediate cell layer as well as in the basal cell layer. Areas of squamous metaplasia showed high labelling indices, however the proliferative cells were restricted to the basal cell layer. The bromodeoxyuridine labelling index thus increases with increasing grade of atypia.

Animals↗
PubMed1988

Activity of the human blood group ABO, Se, H, Le, and X gene-encoded glycosyltransferases in normal and malignant bladder urothelium.

Immunohistochemistry has led to the finding of an expression of ABO-related blood group antigens in normal and malignant bladder urothelium which is different from that found on erythrocytes from the same individual. This includes a loss of blood group ABO expression in malignant urothelium, and the expression of Leb antigens in normal and malignant cells from individuals with Le(a+b-) and Le(a-b-) erythrocytes. To elucidate the mechanism of this blood group antigen expression in urothelium we have analyzed the activity of the specific glycosyltransferases encoded by the ABO, Se, H, Le, and X blood group genes in normal and malignant urothelium. Biopsies of normal urothelium were obtained from 22 individuals and biopsies of urothelial tumors from 20 individuals. The tissue donors were typed for ABO, Lewis, and secretor status on erythrocytes and saliva. The biopsies were disaggregated to single cell suspensions, and the activity of the individual glycosyltransferases was determined as pmol of labeled sugar incorporated by oligosaccharide acceptors per 100,000 cells. The A (alpha-3-N-acetyl-D-galactosaminyl) and B (alpha-3-D-galactosyl) gene-specified transferases showed no activity in malignant cells, whereas all other enzymes examined were expressed in both normal and malignant cells. Secretors and nonsecretors showed the same alpha-2-L-fucosyltransferase activity in both normal and malignant cells, whereas the alpha-3-L-fucosyltransferase was reduced (P less than 0.02) in malignant cells from Lewis positive individuals. The Lewis gene-encoded alpha-4-L-fucosyltransferase showed a similar activity in Lewis positive and negative individuals. These results indicate that the disappearance of A and B blood group antigens in bladder tumors and the expression of Leb antigens in normal and malignant cells from individuals with Le(a+b-) and Le(a-b-) erythrocytes are due to corresponding differences in glycosyltransferases. The results indicate that the ABO, H, Se, and Le genes are subjected to a tissue-dependent differential expression.

ABO Blood-Group System↗