Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An antigen has been isolated from a human signet-ring cell carcinoma serially growing in hamsters, GW-39, by saline, PCA, or phenol extraction, and has been found immunologically identical to a similarly extracted substance in normal human or hamster colon. No other hamster or human tissues or cells were found to contain this antigen, for which reason we have termed it colon-specific antigen, or CSA. CSA has been found to be distinct from the major blood group-specific antigens and from othercolon tumor-associated antigens, such as CEA, CCA-II, and CCA-III. It thus seems that a colon organ-specific antigen can be synthesized by this particular human tumor system. Hamsters immunized with CSA could reject cheek pouch grafts of GW-39 tumors, and tumor rejection by these animals correlated with their anti-CSA antibody titers. Preliminary characterization of CSA suggested that it is a glycoprotein on the cell surface having a molecular size of 30,000 to 50,000 daltons. It is proposed that CSA may play a role in the diagnosis of mucin-producing adenocarcinoma of the colon and in ulcerative colitis.
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PMID:Identification of a colon-specific antigen (CSA) in normal and neoplastic tissues. 4 58

Several radiopharmaceuticals have recently been shown to have a considerable affinity for malignant tissue. All the tumor-seeking radiopharmaceuticals in current use are nonspecific and may also be picked up by benign tumors and infectious processes, including abscess and granuloma. The sensitivity of the tumor-imaging procedure depends on the radiopharmaceutical employed, the type of tumor, its size and location, and previous or current treatment. Gallium-67 citrate (67Ga), the most widely used tumor-seeking radiopharmaceutical, seems to have its greatest value in detecting bronchogenic carcinomas irrespective of cell type. The sensitivity for lung cancer in 489 studies was 93 per cent. Gallium-67 is also of great value in the staging of Hodgkin's disease, in which its sensitivity is 87 per cent. Non-Hdgkin's lymphomas are detected with only slightly lower sensitivity. There is, in fact, evidence that 67Ga is at least complemenatry, if not more sensitive than lymphangiography, in the staging of lymphoma. However, adenocarcinomas originating in the gastrointestinal tract are detected by 67Ga with a sensitivity of only about 40 per cent, whereas various chelates of bleomycin (including 111In-Bleo, 99mTc-Bleo and 57Co-Bleo) detect adenocarcinoma of the gastrointestinal tract with considerably higher sensitivity. In the few studies available comparing bleomycin chelates, 57Co-Bleo and 99mTc-Bleo appear to be more sensitive in detecting tumor than 111In-Bleo. Other tumor-seeking radiopharmaceuticasl which have been employed with somewhat less success include selenium compounds, labeled pyrimidines, several inorganic cations, lanthanide chelates and labeled proteins. Yet to be evaulated clinically is the efficacy of radiolabeled antibodies which are specific for tumor antigens, such as 131I-anti-CEA (carcinoembryonic antigen).
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PMID:Cancer diagnosis. The role of tumor-imaging radiopharmaceuticals. 5 31

Pleural and peritoneal fluids from humans with pathological diseases were examined for the presence of carcinoembryonic antigen-like substances (CEA-LS). Among eight samples tested by a solid phase radioimmunoassay, two pleural fluids and one peritoneal fluid showed significantly elevated CEA-activity. The substances responsible for the CEA-activity were isolated by perchloric acid-extraction followed by two successive Sephadex G-200 chromatography into two pools, Pool I (PI) and Pool II (PII). According to their sedimentation properties, PII was slightly smaller than CEA from tumor tissue-extract (CEA-TTE), while PI was larger than CEA-TTE and approximately twice the size of PII. Micro-double diffusion and antibody binding studies showed that CEA-LS possessed identical antigenic determinants as CEA-TTE, which did not cross-react with normal colon antigen (NCA).
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PMID:Carcinoembryonic antigen-like substances in human cavity fluids. 6 11

Palliative treatment was applied to 131 cases of unresectable or palliatively resected colorectal carcinoma being monitored with serial CEA determinations. There were 84 instances of disease progression with 67 (80%) of them showing an increase in CEA above pretreatment levels or maintaining high levels, and 17 (20%) showing a fall when compared to pretreatment values or maintaining low initial values. There was a clear-cut regression of the disease in only 9 instances. In all 9, the CEA clearly dropped or maintained low valles throughout the period of regression. No patient in regression had a rise or maintained an elevated CEA level. These changes in CEA followed closely the clinical response of our patient to the use of a particular agent, although for the Nitrosourea compounds there may be a tendency to lower the CEA regardless of the patient's tumor response to the drug. This could be due to the fact that the Nitrosoureas produce a diffuse block of cellular activity, both at the nucleous and cytoplasm; while other compounds act as alkylating agents or by inhibition of enzymes involved in the metabolism of nucleic acids (i.e., 5-FU inhibiting thymidylate synthetase). In general, longer survival was found in those patients who had initially lower levels of CEA as compared to those with high initial levels. The patients with a favorable CEA response to the treatment (falling CEA or maintained low value), even in many who did not show a clinical response had a longer survival than the group with rising or stable high levels. The main value in CEA monitoring of patients resides in its correlation with the amount of disease present and then its ability to detect progression of tumor mass which is not clinically measurable.
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PMID:CEA monitoring of palliative treatment for colorectal carcinoma. 6 32

A membrane-associated glycoprotein fraction, referred to a CEA-M was isolated from human colonic tumor tissue by sodium dodecyl sulfate extraction of membrane fragments followed by wheat germ agglutinin affinity chromatography, Bio-Gel A-1.5 gel filtration and preparative slab gel electrophoresis. With a m.w. of approximately 200,000, isoelectric point of about 4.2 and carbohydrate:protein ratio of 2:1, this glycoprotein has physiocochemical and antigenic similarities to carcinoembryonic antigen, CEA. Immunochemical studies have shown that antiserum developed for this glycoprotein possesses relative specificity for human colonic carcinomas. Chemical cleavage of this glycoprotein by 2-nitro-5-thiocyanobenzoic acid resulted in three major Coomassie Blue and two periodic acid Schiff stainable fragments (one of which stains with both). It was found that one of the glycopeptides, labeled as TA, isolated by affinity and covalent chromatography, contained 77% carbohydrates and possessed antigenic determinants recognized by at least 70% of the antibody population raised against the total glycoprotein fraction; purified antibodies to this region of the molecule seem promising for the development of a specific assay for gastrointestinal tumors.
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PMID:Colonic tumor membrane-associated glycoprotein: isolation of antigenically-active peptides after chemical cleavage. 6 65

In the present review we have discussed antigens, principally the CEA, which have their well defined place in the clinical management of the (malignant) diseases of the gastrointestinal tract. Though the immunological diagnosis of neoplasia is one of the research areas where the most effort and hopes are invested, it is also there, that the carcinofoetal antigens have the least usefullness at the moment. However, studies like those undertaken by Edgington and Plow are probably pointing out if not proving, that even relatively simple procedures like further purification of the antigen can improve its tumor specificity and consequently its diagnostical value (1975). Following their results the final verdict is not spoken yet as to whether CEA (or any other CFA) will even be more than an adjunctive tool in the diagnosis of malignant tumors specially those of the G.I. tract. The 0.6% of "false" positives these authors have obtained in their series with their highly purified CEA-S (against the 30% usually seen with classical CEA preparations) are provocative: one will have to discuss the question, on which grounds the decision "false positive" has been reached and whether these cases are not simply "clinically silent", hence true positive observations. The problem then would be shifted away from the CEA test (or any other CFA test) toward the improvement of all the other conventionally employed diagnostical measurements, which should allow the early confirmation--and localization--of a beginning neoplasia, which has been screened out by an immunological test. Until this is not warranted, the CEA test has its definite place and vocation at the present time in the follow-up of the treated cancer patient, whatever therapy he has received.
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PMID:The possible role of the carcinoembryonic antigen (CEA) and other carcinofetal antigens in maligant and benign diseases of the gastrointestinal tract. 7 40

Although several investigators have reported serum alpha-fetoprotein positive gastric cancer with or without metastasis to the liver, its site of production is still unclear. We studied on the site of alpha-fetoprotein synthesis in our cases which showed remarkably high level of serum alpha-fetoprotein, and clarified the presence of alpha-fetoprotein producing gastric cancer by means of direct immunofluorescent technique. However, we also knew the hepatocytes adjacent ot the metastatic lesions could also synthesize alpha-fetoprotein, although these hepatocytes were not known whether under regeneration or degeneration. Through this study, the other carcinofetal proteins such as carcino-placental alkaline phosphatase and CEA were examined using the sera or tumor tissues. Our results will support the idea that cancer is the disease of cell differentiation.
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PMID:Carcino-fetal proteins and gastric cancer: the site of alpha-fetoprotein synthesis in gastric cancer. 7 49

Serum AFP was determined serially by radioimmunoassay in 13 patients with ovarian germ cell tumors and in one patient with bilateral pure gonadoblastoma. There were 4 patients with pure dysgerminoma, one with pure endodermal sinus tumor (EST) and 8 with mixed germ cell tumors, all containing EST. The patients with dysgerminoma and gonadoblastoma had normal serum AFP at all times. All patients with tumors containing EST had raised serum AFP, although in most cases it was first determined between 1 and 3 weeks after operation and there was no evidence of metastases. Serum AFP became normal 5 to 7 weeks after operation and began to rise when disease recurred. Serum AFP determinations detected presence of recurrent disease long before it became detectable by other methods. Serum CEA was determined serially by radioimmunoassay in 8 of these patients, including 2 who dies with metastases, and was normal on all occasions.
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PMID:Serum alphafetoprotein (AFP) in diagnosis and management of endodermal sinus (yolk sac) tumor and mixed germ cell tumor of the ovary. 7 54

Carcinoembryonic antigen is only a tumor assoicated antigen and is less clinically useful than the original report suggested. However, the CEA assays in clinical use utilize reagents operationally defined by old criteria. There is now abundant evidence that "CEA" consists of a heterogenous family of related glycoproteins with shared, as well as distinctive, antigenic determinants. Antigenic differences can be demonstrated between some cancer sera "CEA" and various operationally defined tissue "CEA" preparations. Further definition of the biochemical and antigenic characteristics of serum and tumor tissue "CEA" is required in order to determine whether a more tumor specific antigenic determinant can be identified.
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PMID:The immunochemical complexity of CEA: a golden dream or molecular nightmare? 8 10

Colon-specific antigen-p, or CSAp, was originally extracted from GW-39 tumors, which are human colonic carcinomas serially transplanted in golden hamsters, and antibodies to CSAp have been produced in the same animal hosts. By means of immunodiffusion and a hemagglutination-inhibition assay, CSAp has been found to be restricted to adult and fetal small intestine, neoplastic gastric and colonic tissues, inflamed colon, and cystic mucinous tumors of the ovary. CSAp was shown to be distinct from blood group antigens, including Lea and Leb blood group substances, liver ferritin, AFP, CEA, CSA, CMA, ZGM, and BOFA, and to have the electrophoretic mobility of an alpha2-globulin. Gel filtration studies indicated that CSAp in GW-39 tumor, primary human colonic carcinoma, and ovarian cancer mucinous cyst fluid had a peak molecular size range of 70,000--110,000. Quantitation of CSAp in 214 tissue specimens by the hemagglutination-inhibition assay revealed a progressive increase in fetal, inflamed, and neoplastic intestine, such that CSAp in colonic tumors was increased over normal colon tissue. Thus, CSAp appears to be an organ-specific antigen showing increased levels in some gastrointestinal and ovarian neoplasms, as well as in specimens with colitis.
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PMID:Further characterization of CSAp, an antigen associated with gastrointestinal and ovarian tumors. 8 13


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