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 loss of HLA antigens by neoplastic cells may allow tumors to escape immune surveillance. We observed reduced expression of HLA antigens during human colon carcinogenesis. Since ethanol, which is associated with human colonic carcinogenesis, modulates the expression of HLA genes, we examined whether it affects the expression of HLA class I genes in human colon adenocarcinoma cell lines. Ethanol (1.7 x 10(-10) M to 1.7 x 10(-1) M), had no effect on the expression of HLA class I antigens on these colonocytes, the corresponding mRNA levels, or the expression of HLA constructs. Our findings do not support the hypothesis that ethanol may modulate the expression of HLA class I genes in human colon cancer cells.
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PMID:The effect of ethanol on the expression of HLA class I genes in human colon adenocarcinoma cell lines. 801 85

A 78-years-old man suffered from sympathetic ophthalmia. He had been treated with 5-fluorouracil (5-FU) for metastasis of colon cancer in the liver. He received a perforating eye injury in the left eye thereafter the eye became phthisic. Two months after the injury, he noticed visual disturbance in the right eye. He was treated with large doses of systemic corticosteroid after a diagnosis of uveitis of the right eye, but the visual acuity of the right eye became worse. The eye showed non-specific diffuse uveitis. A diagnosis of sympathetic ophthalmia was made from previous history and ocular findings. We enucleated the injured eye and continued the systemic corticosteroid. Then the right eye improved. Histopathological examination of the enucleated eye revealed the choroid was infiltrated with a granulomatous lesion of lymphocytes and epithelioid cells. HLA typing showed DR4, DR8, DR52, DR53, and DQ1, and we made a final diagnosis of sympathetic ophthalmia. It is probable that the clinical findings were modified by the 5-FU treatment and the patient's advanced age.
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PMID:[Sympathetic ophthalmia in an elderly man]. 815 92

Loss of HLA antigen expression is considered to be one of the mechanisms whereby tumor cells escape immune surveillance. We recently observed reduced or lost expression of HLA antigens during human colon carcinogenesis. We studied the effect of bile acids (BAs), long implicated in the pathogenesis of colon cancer, on the expression of HLA class I antigens in human colon adenocarcinoma cells. Lithocholic acid (LCA) decreased by 42% the expression of HLA class I antigens on the surface of these cells. This dose-dependent reduction was specific for both the target genes and the chemical structure of LCA, and was not evident in cultured liver cells. None of the other BAs that were tested manifested this effect. LCA, and to a lesser extent deoxycholic acid (DCA), decreased steady-state HLA class I mRNA levels. LCA decreased the rate of transcription of HLA-B (64%) and HLA-C (87%) but not HLA-A; DCA had a similar but less pronounced effect. In transient gene expression (CAT assays) experiments, we evaluated the role of a 0.6-0.7 kb EcoRI/XbaI sequence from the 5' flanking region of HLA-A2, -B7 and -Cw7 genes in the regulation of class I gene expression by LCA. LCA down-regulated by 70% the expression of the reporter gene for all three genes. We interpret these results as indicating a differential regulation of the three HLA loci by LCA. Our findings, demonstrating a profound effect of LCA on HLA class I gene regulation, raise the possibility that such a mechanism may be operative in vivo.
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PMID:Lithocholic acid inhibits the expression of HLA class I genes in colon adenocarcinoma cells. Differential effect on HLA-A, -B and -C loci. 819 71

Recent molecular biological approach has revealed the primary structure of some mucin core proteins. Most prominent characteristic is tandemly repeated sequences. cDNA cloning of 6 kinds of mucin core proteins, MUC1-6, have thus been performed. Among them, the entire structure was revealed on MUC1 and 2. MUC 1 is a type I transmembrane protein with a large number of tandem repeat consisting of 20 amino acids. We have found that mouse MoAb MUSE11 against adenocarcinoma, which detects circulating MUC1 in patients with gastrointestinal and pancreatic cancers, recognizes part of the tandem repeat of MUC1 using synthetic peptides. To date, some of the MoAbs to adenocarcinoma which were prepared for the last decade have been shown to react with the tandem repeat of MUC1(MUC1 epitope), suggesting that MUC1 epitope could be highly immunogenic in human. Recently, cytotoxic T-cells against MUC1 epitope were established from breast and pancreas cancer patients. We could also induce those T-cells from the patient with multiple myeloma. Interestingly, CTL functions in a HLA-unrestricted manner, and may be of use as an adoptive immunotherapy. In addition, we have found antibody against MUC1 epitope in patients with ulcerative colitis or colon cancer. EB virus-transformed B-cell clone producing antibody against MUC1 epitope has been established from a cancer patient. Thus, MUC1 is now considered as a targeting molecule for immunotherapy. Indeed, Longenecker's group in Canada has recently tried the basic evaluation for immunotherapy using synthetic peptides of MUC1.
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PMID:[Molecular biological analyses of mucin core proteins and their clinical application]. 831 84

To detect shared human melanoma Ag that are recognized by HLA-A2 restricted, melanoma-specific CTL derived from tumor infiltrating lymphocytes, we have developed a convenient method to insert and express foreign HLA genes capable of presenting Ag on target cell lines. Seventeen melanoma cell lines and 11 nonmelanoma cell lines were infected with recombinant vaccinia virus containing the HLA-A2.1 gene. Infection by the vaccinia virus resulted in expression of functional HLA-A2 molecules on the cell surface of virtually 100% of infected cells within a 3.5-h period. The results showed that 11 of 17 (65%) naturally HLA-A2- melanoma cell lines were specifically lysed by the HLA-A2-restricted, melanoma-specific TIL after infection with the vaccinia-HLA-A2.1 virus. None of the nine human nonmelanoma cell lines tested (three colon cancer, four breast cancer, or two immortalized non-tumor cell lines) or two murine melanoma cell lines were lysed by the HLA-A2-restricted TIL after vaccinia-HLA-A2.1 infection. Coinfection of the vaccinia virus containing the beta 2-microglobulin gene with the vaccinia-HLA-A2.1 virus increased the surface expression of HLA-A2 and subsequent lysis by melanoma-specific tumor infiltrating lymphocytes. With this new method we could extend previous findings demonstrating that shared melanoma Ag recognized by HLA-A2-restricted tumor infiltrating lymphocytes exist among melanoma cells from different patients regardless of HLA type. These Ag represent excellent candidates for the development of vaccines to induce T cell responses for the immunotherapy of patients with melanoma.
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PMID:Detection of shared MHC-restricted human melanoma antigens after vaccinia virus-mediated transduction of genes coding for HLA. 833 37

The loss of HLA antigens by neoplastic cells is considered important for tumor growth and metastasis, inasmuch as it may allow tumors to escape immune surveillance. We have observed reduced expression of HLA antigens in sporadic colon cancer and adenomas from familial adenomatous polyposis patients. We now studied the expression of HLA class I antigens in patients with sporadic adenomas, which are precursors of colorectal cancer. Expression of HLA class I antigens was studied by immunohistochemistry in (a) sporadic colon adenomas, (b) histologically normal mucosa distant from the adenomas, (c) histologically normal colonic mucosa from patients with history of sporadic colon adenomas, and (d) colonic mucosa from normal subjects. HLA class I antigen expression was moderately reduced in 56% and severely reduced in 44% of the adenomas; this reduction was significant when compared to controls (P < 0.0001). The reduction of HLA class I expression in adenomas was related to the grade of dysplasia of the adenomas. HLA class I expression of normal appearing mucosa was decreased in 76% of patients with adenoma (P < 0.0001) and in 54% of patients with history of adenoma (P < 0.005) compared to normal controls. These changes were antigen specific, inasmuch as the expression of carcinoembryonic antigen, a surface antigen, was not affected. Our findings suggest that reduced HLA class I expression is an early event in the cell transformation process from normal to neoplastic state, preceding in many cases the onset of histological changes. HLA class I could be potentially used as a premalignant marker in the colon.
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PMID:Expression of HLA class I antigens in sporadic adenomas and histologically normal mucosa of the colon. 848 24

Colon cancer cells express potentially immunogenic proteins but are not rejected by the immune system. To induce an effective immune response, antigenic peptides have to be presented to T lymphocytes by professional antigen-presenting cells in association with HLA class II molecules. Antigen-presenting cells also have to express B7 family molecules, B7-1 and B7-2, which deliver the costimulatory signals that are required to prevent T cell anergy. We studied B7-1 and B7-2 expression by the antigen-presenting cells that infiltrate colorectal cancer stroma. In 25 samples of colorectal carcinomas, a panel of monoclonal antibodies was used to label macrophages, dendritic cells, and T lymphocytes that infiltrate the tumor stroma and the morphologically normal distant mucosa. The expression of HLA class II and B7 molecules involved in T-cell activation was studied using specific monoclonal antibodies. Biopsy pieces from two patients with active Crohn's disease were used as controls. All of the samples were heavily infiltrated by macrophages and/or dendritic cells that strongly expressed HLA class II molecules. In contrast, antibodies to B7-1 and/or B7-2 stained no cells in 16 of the 25 samples of colorectal tumors and less than 1% of the inflammatory cells that infiltrated tumor stroma of the other nine tumor samples. B7 molecules were also poorly expressed by rare cells in the lamina propria of the morphologically normal colorectal mucosa. In contrast, many inflammatory cells that infiltrated the two Crohn's disease samples strongly expressed B7-1 and B7-2, especially in the granulomas. We conclude that most HLA class II+ inflammatory cells that infiltrate colorectal cancers do not express the B7-1 and B7-2 costimulatory molecules. This defect may contribute to the failure of the immune system to recognize tumor cells as antigenic.
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PMID:Inflammatory cells infiltrating human colorectal carcinomas express HLA class II but not B7-1 and B7-2 costimulatory molecules of the T-cell activation. 864 92

The concept of predictive medicine based on the detection of genetic markers for disease susceptibility stemmed from the finding that many diseases are associated with specific HLA alleles. This model suggested that similar associations probably existed with other genes located all along the human genome. The Human Specimen Study Center (HSSC) was created to assist in investigating this possibility and has contributed significantly to the knowledge contained in current genetic and physical human genome maps. Predictive medicine is intended not for patients but for healthy individuals, its goal being to determine whether their susceptibility to a specific disease is increased or not. Fetuses with evidence of disease are excluded from the province of predictive medicine, which can, however, determine whether a healthy fetus is at high risk for developing a disease in adolescence or adulthood. Predictive medicine is based on probabilities: it evaluates diseases susceptibility but cannot predict with 100% certainty that a specific disease will occur. Whereas many preventive interventions are directed at groups (e.g., immunization programs), predictive medicine is conducted on an individualized basis. For instance, glaucoma is a monogenic disease whose early detection can allow to prevent permanent loss of vision. The fruits of predictive medicine are expected to be greatest, however, in the polygenic multifactorial diseases that are prevalent in industrialized countries, such as diabetes mellitus, hypertension, myocardial infarction, hyperlipidemia, and arteriosclerosis. An ability to detect subjects who are susceptible to breast cancer would be extraordinarily useful, and may be a goal within reach since two breast cancer susceptibility genes have already been identified. Genes associated with increased susceptibility to colon cancer have also been reported. Predictive medicine raises a number of sensitive ethical issues. Individuals should be free to accept or decline disease susceptibility testing after having been fully informed. Confidentiality is vital. The results of susceptibility tests should not be made available to employers or insurance agencies. Susceptibility testing should be offered only if the disease requires a specific treatment or lifestyle modification. Unnecessary anxiety may be one of the main adverse effects of susceptibility testing. A large number of disease susceptibility or resistance genes will probably be identified in the near future, and this will inevitably have an impact on the way physicians approach their patients. Physicians in the XXIst century will spend an increasingly large proportion of their time counselling their patients on how to stay healthy. This trend can be expected to translate into a marked increase in life expectancy. Rather than seeking to add years to life, physicians will strive to add life to years.
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PMID:[Predictive medicine and its ethics]. 929 63

MHC class I associated peptides on cancer cells represent potential targets for CD8+ cytotoxic T cell activity against tumor cells. We eluted the naturally bound MHC class I peptides of a colon carcinoma cell line and compared them to peptides isolated from a B cell line and a slow-growing activated Ki-ras-disrupted colon cancer cell line. While we failed to detect any significant differences in class I associated peptides due to the presence or absence of activated Ki-ras in colon cancer cell lines, the colon cancer cell lines and B cell line presented vastly different peptide repertoires in the context of HLA-A*0201 molecules.
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PMID:MHC class I bound peptides of a colon carcinoma cell line, a Ki-ras gene-targeted progeny cell line and a B cell line. 948 88

We report a patient with four conditions in association with linear IgA disease (LAD), only three of which have been reported previously; these latter are ulcerative colitis, autoimmune thyroid disease and carcinoma of the colon, although the carcinoma may have been caused by the ulcerative colitis in this case. Recently, our patient also presented with respiratory symptoms and was found to have sarcoidosis as well, a previously unreported association of this autoimmune bullous disorder. The aetiology of this development may be related to the patient's HLA status or possibly to his treatment with the immunosuppressive agent cyclophosphamide; it is also possible that it is coincidental.
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PMID:Sarcoidosis in a patient with linear IgA disease. 1023 55


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