Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We recently reported the presence of an organ-specific 40 kD colonic protein which acts as an autoantigen(s) in patients with ulcerative colitis. Using a specific monoclonal antibody directed against 40 kD protein (7E12H12, IgM isotype), in conjunction with immunocytochemistry and flow cytometry, we examined the presence of the 40 kD protein on human colon cancer cells, DLD-1, and also characterized the ability of cytokines, IFN-gamma and tumour necrosis factor, to modulate the expression of this protein on these tumour cells. The presence of the 40 kD protein was localized to the plasma membrane; less was present within the cytoplasm. Following exposure to IFN-gamma (10-1000 U/ml), DLD-1 colon tumour cells showed a dose- and time-dependent increase in 7E12H12 antibody associated immunofluorescence, with the maximum 7E12H12 antibody binding observed with 100 U/ml IFN-gamma at 48 h. In contrast, tumour necrosis factor did not alter the levels of anti-40 kD antibody binding over that of control cells. Since IFN-gamma is also known to induce class II major histocompatibility antigens, we examined the possibility of cross-reactivity of HLA class II antigens and Mr 40 kD epitope. Neither pre-incubation of DLD-1 colon tumour cells with anti-HLA class II antibodies followed by 7E12H12 nor co-incubation of both antibodies altered the amount of 7E12H12 antibody binding. Using a direct ELISA, a highly enriched preparation of Mr 40 kD protein reactive to anti-40 kD antibody did not react with HLA class II antibodies. The present results suggest that 40 kD protein is present on DLD-1 human colon tumour cells and that although the 40 kD protein epitope expression is increased by the lymphocyte-derived cytokine, IFN-gamma, the epitope is separate and distinct from the class II HLA antigens. Further studies on the 40 KD protein may elucidate its autoantigenic role in the pathogenesis of inflammatory bowel disease.
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PMID:Expression of the 40 kD protein in DLD-1 colon cancer cells and the effect of cytokines. 137 49

Three predominantly CD8+ CTL lines, TIL 501, TIL 620, and TIL 660, were generated from three HLA-A2+ melanoma patients by culturing tumor-infiltrating lymphocytes in 1000 U/ml IL-2. These tumor-infiltrating lymphocytes lysed 12 of 18 HLA-A2+ autologous and allogeneic melanomas, but none of 20 HLA-A2-negative melanomas. They also did not lyse the MHC class I negative lymphoma-leukemia cell lines, Daudi, K562, or HLA-A2+ non-melanoma cell lines including PHA or Con A-induced lymphoblast, fibroblast, EBV-transformed B cell, Burkitt's B cell lymphoma, and colon cancer cell lines. Autologous and allogeneic melanoma lysis was inhibited by anti-CD3, by anti-MHC class I, and by anti-HLA-A2 mAb, indicating recognition of shared tumor Ag among melanoma cell lines in a TCR-dependent, HLA-A2-restricted manner. Six HLA-A2-negative melanoma cell lines obtained from five HLA-A2-negative patients were co-transfected with the HLA-A2.1 gene and pSV2neo. All 17 cloned transfectants expressing cell surface HLA-A2 molecules, but none of 12 transfectants lacking HLA-A2 expression, were lysed by these three HLA-A2-restricted, melanoma-specific CTL. Lysis of the HLA-A2+ transfectants was inhibited by anti-CD3, by anti-MHC class I, and by anti-HLA-A2 mAb, indicating recognition of shared tumor Ag on transfectants in a TCR-dependent, HLA-A2-restricted manner. These results identify the HLA-A2.1 molecule as an Ag-presenting molecule for melanoma Ag. They also suggest that common melanoma Ag are expressed among melanoma patients regardless of HLA type. These findings have implications for the development of melanoma vaccines that would induce antitumor T cell responses.
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PMID:Shared human melanoma antigens. Recognition by tumor-infiltrating lymphocytes in HLA-A2.1-transfected melanomas. 172 79

The human colon cancer cell line HCT does not express any detectable HLA class I antigens on the cell surface. RNA blot analyses showed that HCT cells synthesize easily detectable levels of heavy chains as well as beta 2-microglobulin (beta 2m) transcripts. Experiments of immunoprecipitation revealed the presence of intracellular HLA heavy chains and the absence of beta 2m molecules. Sequencing studies, performed on polymerase chain reaction-mediated amplification of beta 2m-specific complementary DNAs, indicated that in HCT cells both beta 2m genes are mutated. The first mutation consists of an 11-base deletion, corresponding to the first 11 base pairs of the second exon of the beta 2m gene. This mutation alters the reading frame, starting from the third amino acid residue of the mature beta 2m protein, resulting in the synthesis of a 31-amino acid peptide with no remarkable homology to any of the sequences stored in the protein database. The second mutation is a point mutation (C----A), resulting in a UAA stop codon corresponding to the 10th amino acid residue of the mature beta 2m. Therefore, it would appear that in HCT cells the beta 2m genes have undergone two different mutational changes. This is the first molecular demonstration of beta 2m mutations in a human epithelial cell line.
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PMID:Beta 2-microglobulin gene is mutated in a human colon cancer cell line (HCT) deficient in the expression of HLA class I antigens on the cell surface. 173 80

Fatal transfusion-associated graft-versus-host disease developed in a 69-year-old woman with colon cancer who underwent elective hemicolectomy. During the perioperative period, she was transfused with 4 units of nonirradiated fresh whole blood less than 6 hours after the blood was donated by family members. She was immunocompetent and was not treated with any immunosuppressive agents such as corticosteroids, chemotherapy, or irradiation therapy. The implicated donor was thought to be her daughter, who was homozygous for an HLA haplotype that was shared with the recipient: A24, Bw52, CBL, DR2. This is the most common haplotype in the Japanese population. This case and others in the Japanese literature indicate that the transfusion of fresh, nonirradiated blood that contains immunocompetent lymphocytes and peripheral hematopoietic precursor cells from HLA-homozygous donors can be lethal to the recipient.
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PMID:The critical role of blood from HLA-homozygous donors in fatal transfusion-associated graft-versus-host disease in immunocompetent patients. 200 27

The expression of HLA class I and II antigens was studied by immunohistochemistry in (a) specimens of colon cancer from 25 patients, (b) normal colonic mucosa obtained 5-10 cm away from each tumor, and (c) colonic mucosa from 13 normal individuals. Thirteen of the tumor specimens had normal epithelium adjacent to the cancer, which thus served as an internal control. The expression of HLA class I antigens in colon cancer was dramatically reduced compared to control (P less than 0.0001): undetectable in 28%, diminished in 68%, normal in 4%. The expression of class II antigens was also reduced in cancer (P less than 0.0001 for all when compared to normal), being undetectable in most (HLA-DP 64%, HLA-DQ 72%, HLA-DR 68%). In 44% of the cancers all three HLA class II antigens were undetectable; in 92% at least one class II antigen was undetectable; and in 20% both class I and class II antigens were undetectable. No cancer specimen had a completely normal HLA phenotype. The expression of other surface antigens was preserved in cancer tissues and, therefore, loss of HLA antigens was not due to a nonspecific decline in surface molecules. When glands of normal mucosa immediately adjacent to cancer were compared to those of normal controls, significantly reduced expression of only HLA class I antigens (P = 0.0149) and HLA-DP (P = 0.034) was found. The expression of the HLA antigens in colonic mucosa remote from the cancer was no different from that of normal controls. Our data show extensive and significant reduction in the expression of HLA antigens in colon cancer; its potential relationship to immunosurveillance in cancer is discussed.
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PMID:Reduced expression of HLA class I and II antigens in colon cancer. 212 44

Monoclonal antibody F30 was produced by the fusion of murine myeloma cell line P3-X63-Ag8-653 with spleen cells from a BALB/C mouse immunized with established human pancreatic cancer cell line (PK-1) and the reaction specificity was analyzed. The antigen recognized by monoclonal antibody F30 was different from HLA-associated antigen, beta 2-microglobulin, fetal bovine serum components, ferritin, AFP, or CEA. Monoclonal antibody F30 reacted with all of six pancreatic cancer cell lines established in our laboratory. Cross-reactivity was detected with a colon cancer cell line or an esophagus cancer cell line among various tumor cell lines tested. No reaction was detected with red blood cells, lymphocytes, or lymphoid and myeloid cell lines. By immunoperoxidase staining of frozen sections, the F30-defined antigen was detected not only on pancreatic cancer cell membrane but also on other adenocarcinomas. In addition, the monoclonal antibody F30 had a more wide-spread distribution on normal epithelial cells in the gastrointestinal organs, respiratory system, and urinary system. F30-defined antigen was composed of two protein components with molecular weight of 190 and 160 K. It was indicated that the antigen was an integral protein in the cell membrane since the antigen was not detected in the spent culture medium of antigen-positive cells.
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PMID:Human pancreatic cancer associated antigen detected by monoclonal antibody. 351 31

Cytotoxicity of peripheral blood mononuclear cells of 30 patients with Crohn's disease (CD) and 30 matched controls was assayed by measuring isotope release from 75Se-L-methionine labelled RPMI 4788 human colon cancer cells. Effector populations were studied with and without monocyte depletion after 4 and 24 hr incubations in 10% fetal calf serum or autologous serum or plasma. Cytotoxicity was negligible at 4 hr. Twenty-four hour cytotoxicity was consistently lower in CD patients than in healthy controls, mean values ranging from 13.6 +/- 2.7% (s.e.m.) to 19.5 +/- 3.7% in patients and from 27.2 +/- 4.1% to 33.6 +/- 5.3% in controls. Cytotoxicity of disease controls was not significantly different from that of healthy subjects. Cytotoxicity was reduced by monocyte depletion, was weakly and inversely related to disease activity, was relatively stable for up to 24 months and was not HLA restricted. Cell lysis was attributable to spontaneous cell-mediated cytotoxicity. Antibody-dependent cellular cytotoxicity and antibody-complement-dependent cytotoxicity were not detected.
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PMID:Depressed spontaneous cell-mediated cytotoxicity in Crohn's disease. 660 55

Bone-marrow transplantation for severe aplastic anaemia was performed in a 14-year-old boy in 1969. The transplanted marrow was not HLA identical: there was HLA-D incompatibility between the female donor and the recipient. The patient had had several blood transfusions and one course of cytostatic conditioning before the transplantation. Six years later he had carcinoma of the colon which was completely removed at surgery. Ten years after transplantation, chimaerism was demonstrated in the recipient who was then haematologically and clinically healthy and in full employment. The bone-marrow transplantation can thus be considered as successful.
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PMID:[Successful bone-marrow transplantation after eleven years (author's transl)]. 699 88

A kindred with the familial cancer syndrome is reported in which every confirmed affected member of the pedigree had at least one primary carcinoma of the colon. The average age at which cancer appeared was 38 years, and multiple primary neoplasm occurred in 23% of the cancer patients. Transmission of the cancer trait is consistent with an autosomal dominant mode of inheritance. Colonoscopy eliminated the presence of any unsuspected cancers in family members at risk. HLA typing was done, and by direct typing or inference, data were available on 66 living and deceased individuals. There were four informative matings in the kindred, the offspring of which showed only three crossovers of a possible 17. The lod score totaled 1.06 at a recombination fraction of 0.20. The need for cooperative efforts of many investigators in HLA linkage studies is emphasized, along with the potential value of such an approach.
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PMID:A linkage study of HLA and inherited adenocarcinoma of the colon. 723 94

Prostaglandins (PG) have been implicated in the pathogenesis of cancer and play an important role in immune regulation. Colon cancer is associated with elevated levels of PGE2, while aspirin, the prototypical inhibitor of PG synthesis, appears to reduce the incidence of colon cancer by 50%. We have observed that in human colon cancer the expression of HLA class I and II antigens is reduced or lost; loss of HLA antigens is suspected to be a mechanism by which the malignant cell escapes the immune surveillance. We investigated the effect of these eicosanoids on the expression of HLA antigens in human colon adenocarcinoma cell lines. PGE2 down-regulated the expression of the class II antigen HLA-DR in SW1116 cells (65% reduction at 2.8 x 10(-8) M). This effect was dose- and time-dependent, reversible, and specific (PGF2 alpha and LTB4 had no effect; the expression of carcinoembryonic antigen and class I genes were not affected). Aspirin induced the expression of HLA-DR in HT29 cells, a cell line not expressing constitutively HLA-DR. The reduction of HLA-DR by PGE2 was accompanied by reduced messenger RNA (mRNA) levels of HLA-DR alpha and reduced transcription of the corresponding gene. In contrast to HLA-DR, none of these three eicosanoids affected the expression of HLA class I genes, as assessed via determination of protein expression by fluorescence flow cytometric analysis and evaluation of the corresponding class I mRNA levels. We conclude that PGE2 specifically down-regulates the expression of HLA-DR, while it does not affect the expression of class I antigens.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Prostaglandin E2 down-regulates the expression of HLA-DR antigen in human colon adenocarcinoma cell lines. 772 22


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