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)

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

Recombinant human interferons have recently been shown to enhance tumor antigen expression, including carcinoembryonic antigen (CEA), on the surface of human carcinoma cells, which results in an increase in the targeting of antitumor monoclonal antibodies (MAb) in vivo. We report here the effect of recombinant human gamma-interferon (HuIFN-gamma) on the expression of human CEA and its related transcripts in several human colon carcinoma and normal human fibroblast cell lines. The colon tumor cell lines HT-29, WiDr, and LS-174T were each shown to express different constitutive levels of CEA glycopeptide, as measured by the binding of the CEA-specific MAb COL-4. Treatment with HuIFN-gamma enhanced the level of binding of COL-4 in total cell extracts of HT-29 and WiDr cells 2.5- and 6.5-fold, respectively. Using a CEA complementary DNA probe, this increase in MAb binding was shown to be accompanied by a 6- to 11-fold increase in the steady state levels of three CEA transcripts with sizes of 4.2, 3.5, and 2.8 kilobases. On the other hand, HuIFN-gamma treatment had no effect on the level of COL-4 binding or expression of CEA transcripts in LS-174T colon carcinoma cells, which are high constitutive expressors of CEA glycoprotein. Normal human fibroblast cell lines MRC-5 and WI38 had no detectable cytoplasmic CEA glycopeptide levels nor did they contain detectable levels of CEA mRNA, either before or after treatment with HuIFN-gamma. In contrast, HuIFN-gamma induced the de novo expression of the normal major histocompatibility complex class II antigen, HLA-DR, on HT-29 and WiDr colon cancer cells as well as the two fibroblast cell lines. Treatment of the LS-174T cell line with HuIFN-gamma did not result in the induction of class II HLA-DR antigen. These observations suggest that some common factors may be involved in the regulation of the CEA and class II histocompatibility genes. In addition, the demonstration that HuIFN-gamma enhances CEA expression in some carcinoma cell lines but fails to induce de novo expression of CEA transcripts in fibroblasts supports the potential application of HuIFN-gamma in enhancement of tumor targeting of antitumor MAbs and adds to our understanding of the mechanism of gamma-interferon-mediated up-regulation of some tumor antigens.
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PMID:Modulation of carcinoembryonic antigen messenger RNA levels in human colon carcinoma cells by recombinant human gamma-interferon. 249 18

We reported a rare case of triple cancers with acute lymphoblastic leukemia (ALL) associated with disseminated intravascular coagulopathy (DIC) after the operations of colon cancer and primary lung cancer. A 78-year-old Japanese male, who had been operated upon for colon cancer (adenocarcinoma) on March 1981, metastatic brain tumor (adenocarcinoma) on December 1986, and primary lung cancer (squamous cell carcinoma) on February 1987, was admitted to our hospital because of severe general malaise on December 6 1987. On admission, he had mild hepatosplenomegaly and hemorrhage diathesis such as purpura. Serum LDH increased to 2,515 mU/ml. The white blood cell count was 6,210/microliters with 53% leukemia cells, and the platelet count was 12,000/microliters. A bone marrow was infiltrated with 96.0% leukemia cells. The leukemia cells stained positively for PAS and negatively for peroxidase. Immunological examination of leukemia cells showed that HLA-DR, TdT, B1 and J5 were positive and cytoplasmic Igmu and surface Ig were negative, indicating common ALL. The coagulation studies revealed that the activated partial thromboplastin time was prolonged to 42.0 seconds, FDP increased to 79.9 micrograms/ml, and antithrombin-III decreased to 62%. Chromosome analysis showed a 48, XY, +2, +21q-, t(9;22) karyotype. He was diagnosed as having Ph1 positive ALL associated with DIC. He was treated with vindesine, prednisolone, L-asparaginase, and adriamycin and complete remission (CR) was achieved after two months. But on August 1988, 8 months after CR, ALL and brain tumor relapsed and he died of pneumonia on September 19, 1988.
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PMID:[Ph1 positive acute lymphoblastic leukemia with DIC after operation of colon and lung cancer]. 281 Jul 93

Changes were examined in the expression of Class I and II major histocompatibility complex (MHC) antigens by autochthonous cells of the terminal ileum affected by Crohn's disease. The study was based on the analysis of transmural specimens from terminal ileum segments obtained in the course of ileocolectomy for colon cancer and Crohn's disease. Serial sections were immunostained using monoclonal antibodies directed against monomorphic determinants of HLA-A,B,C, DR, DP, DQ, and the invariant chain (Ii) associated with Class II molecules. Compared with the normal state, the only change in Class I antigen expression occurring in Crohn's disease was the induction of HLA-A,B,C antigens in lymphatic endothelium. Changes in Class II antigen expression were more substantial. Enhancement of HLA-DR expression was found in enterocytes; DR induction was observed in glial cells of the visceral nervous plexus and in venular and venous endothelium. HLA-DP and DQ antigens were induced in enterocytes, glial cells, and capillary and venular endothelium, although this induction was restricted to areas of moderate or high inflammatory activity. The tissue distribution of Ii closely resembled that of HLA-DR, although this association was not strict: on the one hand, arterial endothelium contained low amounts of Ii in the absence of DR antigens; on the other hand, glial cells expressed Class II molecules in the absence of Ii. The extent of local enhancement/induction of MHC antigens was positively correlated with the local density of the cellular infiltrate. These data suggest that altered MHC antigen expression by autochthonous structures might be mediated by factors released from the lymphohistiocytic infiltrate, which is itself attracted by an unknown signal. In conjunction with an unknown antigen, the enhanced expression of Class II antigens might trigger an autoaggressive immune response.
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PMID:Sequential induction of MHC antigens on autochthonous cells of ileum affected by Crohn's disease. 342 89

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

We quantitatively evaluated dendritic cell (DC) infiltration in primary colorectal cancers from 44 patients and metastatic colorectal tumors from 13 patients using immunohistochemistry for the DC marker CD83, HLA-DR, and the DC activation molecules CD40 and CD86. Nearly all CD83+ cells were also HLA-DR+, CD40+, and CD86+, indicating that the DCs that infiltrate colon cancer in vivo express the activation and costimulatory molecules associated with a mature DC phenotype. The density of DCs in colorectal cancer primaries was three times lower than that seen in normal colonic mucosa (0.29 versus 0.84 CD83+ cells/ high-power field (hpf), p < 0.001). Dendritic cells were rarely observed in metastatic tumors: DC density in metastases was sixfold lower than in colorectal primary tumors (0.05 versus 0.29 CD83+ cells/hpf, p < 0.001). Because cytokines have been shown, in vitro, to exert potent effects on DCs, we also evaluated the relationship between intratumor DC density and the expression of cytokines by tumor-infiltrating lymphocytes (TILs) and tumor cells. Expression of interleukin-10 and transforming growth factor beta by either TIL or tumor cells was not associated with decreased DC density or decreased expression of CD40 or CD86 on DCs. Tumor expression of vascular endothelial growth factor was associated with a more than twofold increase in DC density (p = 0.01). Patients who had a high proportion of TILs expressing tumor necrosis factor (TNF) had a greater intratumor mature DC density than patients with a low proportion of TNF + TIL (0.54 versus 0.21 CD83+ cells/hpf, p < 0.01).
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PMID:Dendritic cell infiltration in colon cancer. 1126 70

We quantitatively evaluated dendritic cell (DC) infiltration in primary colorectal cancers from 44 patients and metastatic colorectal tumors from 13 patients using immunohistochemistry for the DC marker CD83, HLA-DR, and the DC activation molecules CD40 and CD86. Nearly all CD83+ cells were also HLA-DR+, CD40+, and CD86+, indicating that the DCs that infiltrate colon cancer in vivo express the activation and costimulatory molecules associated with a mature DC phenotype. The density of DCs in colorectal cancer primaries was three times lower than that seen in normal colonic mucosa (0.29 versus 0.84 CD83+ cells/ high-power field (hpf), p < 0.001). Dendritic cells were rarely observed in metastatic tumors: DC density in metastases was sixfold lower than in colorectal primary tumors (0.05 versus 0.29 CD83+ cells/hpf, p < 0.001). Because cytokines have been shown, in vitro, to exert potent effects on DCs, we also evaluated the relationship between intratumor DC density and the expression of cytokines by tumor-infiltrating lymphocytes (TILs) and tumor cells. Expression of interleukin-10 and transforming growth factor beta by either TIL or tumor cells was not associated with decreased DC density or decreased expression of CD40 or CD86 on DCs. Tumor expression of vascular endothelial growth factor was associated with a more than twofold increase in DC density (p = 0.01). Patients who had a high proportion of TILs expressing tumor necrosis factor (TNF) had a greater intratumor mature DC density than patients with a low proportion of TNF + TIL (0.54 versus 0.21 CD83+ cells/hpf, p < 0.01).
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PMID:Dendritic Cell Infiltration in Colon Cancer. 1144 69

Only a limited number of target molecules have been shown to be recognized by colon tumor-reactive T cells, limiting the options for the development of immunotherapies for patients with colon cancer. The current studies were undertaken in an attempt to generate tumor-reactive T cells that could be used to identify and characterize novel colon tumor-associated antigens. Multiple CD4(+) T-cell clones isolated either from tumor-infiltrating lymphocytes or peripheral blood mononuclear cells that were sensitized in vitro with autologous tumor cells from a colon cancer patient, 1869, recognized autologous tumor cells in a class II HLA-DR-restricted manner. One of the peripheral blood mononuclear cell clones, clone C111, was used to screen pools of clones that were generated from an autologous colon tumor cell line cDNA library. A cDNA clone that was isolated encoded a protein that was termed colorectal tumor-associated antigen-1 (COA-1). This product was recognized in the context of the two autologous HLA-DRbeta1 alleles, HLA-DRbeta1*0402 and DRbeta1*1301. The nucleotide sequence of the COA-1 transcript was nearly identical to multiple expressed sequence tag sequences that encode variants of Socius, a protein that was found recently to bind to members of the Rnd family of GTPases. The COA-1 gene was expressed at relatively comparable levels in colorectal and melanoma tumor cells, EBV-infected B cells, normal B cells, and cultured fibroblast cell lines. However, the gene that was isolated from normal cell types contained a single nucleotide substitution, resulting in an amino acid change near the COOH terminus of the protein. Although the minimal epitope recognized by CD4(+) cells was encoded by sequences that were upstream from this substitution, C111 T cells did not appear to recognize the normal gene product. Therefore, this alteration may either affect the localization or the processing of this gene product, which may at least in part be responsible for the differential recognition of tumor and normal cells.
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PMID:Identification of a colorectal tumor-associated antigen (COA-1) recognized by CD4(+) T lymphocytes. 1458 68

Protein phosphatase 2A (PP2A) is a family of mammalian serine/threonine phosphatases that is involved in the control of many cellular functions including those mediated by extracellular signal-regulated kinase (ERK) signaling. While investigating the reversible antiproliferative effect of the dietary lectin, jacalin, which binds the Thomsen-Friedenreich antigen (galactose beta1-3 N-acetylgalactosamine alpha-), we have found that this lectin (30 microg/ml) induces rapid, transient, tyrosine phosphorylation of putative human HLA-DR-associated protein I (PHAPI, also known as the tumor suppressor pp32) in HT29 human colon cancer cells. This is accompanied by the release of PP2A from association with PHAPI, allowing increased phosphatase activity of PP2A (by 42 +/- 10% at 10 min) and consequent complete dephosphorylation of the ERK kinase, MEK1/2, by 10 min and of ERK1/2 by 60 min. PHAPI knockdown by RNA interference abolished the effects of jacalin on PP2A activation and MEK inhibition. Thus phosphorylation of PHAPI/pp32 is a critical regulatory step in PP2A activation and ERK signaling.
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PMID:Protein phosphatase 2A, a negative regulator of the ERK signaling pathway, is activated by tyrosine phosphorylation of putative HLA class II-associated protein I (PHAPI)/pp32 in response to the antiproliferative lectin, jacalin. 1524 76

Nonsteroidal anti-inflammatory drugs (NSAIDs) decrease the incidence of colon cancer. The underexpression of HLA antigens during colon cancer development is suspected to be a mechanism by which malignant cells escape immune surveillance. We examined whether NSAIDs affect the expression of HLA-DR in HT29 human colon adenocarcinoma cells, which do not express HLA-DR. Aspirin, indomethacin and sulindac induced several-fold the expression of HLA-DR in these cells in a concentration- and time-dependent manner. Aspirin increased HLA-DR alpha steady-state mRNA levels and HLA-DR alpha gene transcription rate. These findings raise the possibility that such a mechanism may be operative in vivo.
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PMID:Aspirin and aspirin-like drugs induce HLA-DR expression in HT29 colon cancer cells. 2154 84


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