Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024623 (gastric cancer)
 36,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tumor-associated glycoprotein (TAG-72) has been shown to be expressed in a wide variety of epithelial malignant tissues. We have investigated serum levels of TAG-72 antigen in patients with gastrointestinal cancer with a solid phase radioimmunometric assay (RIA), CA72-4, utilizing murine monoclonal antibodies CC49 and B72.3 which recognize the TAG-72 antigen. Elevated levels of serum TAG-72 antigen were found in 48% of 56 gastric carcinoma patients and 67% of 45 colorectal carcinoma patients. The serum concentrations of TAG-72 were compared to those of CA19-9 and CEA. The positive rates of CA19-9 in gastric carcinoma and colorectal carcinoma patients were 29% and 54%, and those of CEA were 52% and 60%, respectively. Elevated serum levels of TAG-72, CA19-9 and CEA were observed in 7%, 14% and 24%, respectively, of patients with benign disease, thus indicating a preferential expression of TAG-72, compared to CA19-9 and CEA, in gastrointestinal carcinoma patients versus in patients with benign disorder. A cocktail of CA72-4, CA19-9 and CEA RIAs increased positive rates to 68% in sera of gastric cancer patients and 84% in sera of colorectal cancer patients. Combination assays using CA72-4, CEA and CA19-9 RIAs for patients with benign gastrointestinal disorder, however, also increased the positive rate to 31%. These results indicate that CA72-4, CA19-9 and CEA RIAs may be complementary in detecting circulating tumor-associated antigens. It must be emphasized, however, that interpretation of the data provided by the combination serum assays requires careful consideration.
 ...
PMID:Comparison of serum assays for TAG-72, CA19-9 and CEA in gastrointestinal carcinoma patients. 281 Aug 23

Three human T-cell clones with activated killer activity (5B5, 5C1, and 7B5) which could lyse various tumor cell lines were established. The cytotoxic activity of these clones was decreased by incubation with anti-CD3 monoclonal antibody, suggesting that they recognized tumor cells by T-cell antigen receptor. A monoclonal antibody which blocked the cytotoxic activity of clone 5B5 was obtained. This antibody (N1977) blocked the binding and cytotoxic activity of clone 5B5 at the target cell level, suggesting that the antigen defined by N1977 antibody, designated as ATM-1, was a target molecule recognized by 5B5 cells. ATM-1 in the conditioned medium of a cancer cell line (NBT-2) and serum from a patient with lung cancer was characterized by following its immunoreactivity. On gel filtration, both the conditioned medium and the serum gave three peaks of ATM-1 immunoreactivity, corresponding to approximate molecular weights of 1,200,000, 700,000, and 120,000, respectively. They were chromatofocused at pH 4.0, 4.8, and 6.5, respectively. The high molecular weight forms were shown to be molecules with the disulfide-linked elementary glycoprotein with ATM-1 immunoreactivity and approximate molecular weight of 120,000. Most of the molecules with ATM-1 immunoreactivity bound to both concanavalin A and wheat germ agglutinin, and their binding activity to the antibodies was lost by treatment at 60 degrees C for 30 min. An assay of ATM-1 level in sera was performed by a sandwich enzyme immunoassay. The following positive percentages were obtained from preliminary clinical studies: breast cancer, 67% (8 of 12 cases); hepatocellular carcinoma, 83% (10 of 12 cases); gastric cancer, 58% (7 of 12 cases); lung cancer, 41% (5 of 12 cases); hematological malignancies, 0% (0 of 9 cases); systemic lupus erythematosus, 0% (0 of 8 cases); rheumatoid arthritis, 0% (0 of 8 cases).
 ...
PMID:Identification of a tumor-associated target antigen, ATM-1, for a human T-cell clone with activated killer activity and its existence in sera of cancer patients. 304 79

CA72-4 is a novel quantitative immunoradiometric assay system utilizing two monoclonal antibodies CC-49 and B72.3, which recognize a tumor-associated glycoprotein (TAG-72). We have utilized the CA72-4 RIA kit to measure serum levels of TAG-72 in 205 patients with carcinoma and 192 patients without carcinoma. The cut-off value (4.0 U/ml) was obtained according to the levels and the distribution of CA72-4 in 468 healthy individuals. The positive rates in 82 patients with gastric cancer, 55 with colorectal cancer, 24 with pancreatico-choledochal cancer, 36 with breast cancer, and 3 with ovarian cancer were 52%, 55%, 46%, 39%, and 67%, respectively. Fifty percent of the sera from 205 patients with carcinoma demonstrated increased levels of CA72-4, whereas only 10% of the sera from 192 patients without evidence of malignancy showed levels more than 4.0 U/ml. The average level of serum CA72-4 in the patients with carcinoma was 38.6 U/ml, much higher than that (2.7 U/ml) in patients without malignancy. The patients with gastrointestinal cancer at advanced stages or at recurrence showed higher levels of serum CA72-4 than the patients with cancer at early stages. These results thus indicate that CA72-4 is clinically useful as a novel tumor marker, especially for monitoring serum levels of TAG-72 in patients with gastrointestinal cancer, breast cancer, ovarian cancer and other epithelial malignancies.
 ...
PMID:[Levels of circulating tumor-associated glycoprotein (TAG-72) in patients with carcinoma using a novel tumor marker, CA 72-4]. 316 66

A hybridoma producing monoclonal antibody (H11) directed to lactoneotetraosylceramide (paragloboside) has been established from spleen cells of a mouse immunized with paragloboside. The monoclonal antibody H11 (immunoglobulin M type) was selected from five clones showing different reactivities with paragloboside. The monoclonal antibody was highly specific to paragloboside and lacked reactivity with other glycolipids including glucosylceramide, lactosylceramide, globotriaosylceramide, globotetraosylceramide, gangliotriaosylceramide, gangliotetraosylceramide, and GalNAc beta 1-4[NeuAc alpha 2-3]Gal beta 1-4Glc beta 1-1Cer. However, the monoclonal antibody (H11) was found to bind to lactosamine-containing glycolipids at their terminals, such as i- and I-type glycolipids as well as paragloboside. A two-step sandwich radioimmunoassay method for paragloboside antigen in serum was established by using the monoclonal antibody. The mean paragloboside antigen concentration in the sera from 20 normal individuals was 25.3 ng/ml. If the cutoff value was set at 80.9 ng/ml [25.3 + 2 x 27.8 (SD)], only 1 of 20 healthy controls had an elevated paragloboside value in the serum, whereas sera from 9 of 12 (75.0%) hepatoma, 4 of 10 (40%) pancreatic cancer, 16 of 40 (40.0%) stomach cancer, and 6 of 10 (60%) lung cancer patients had elevated paragloboside values. Sera from 3 of 8 hepatitis patients and 7 of 10 liver cirrhosis patients were estimated to be positive but sera from 16 patients with benign disease had paragloboside levels lower than the cutoff value. A larger amount of the antigen was found in liver metastases from colorectal carcinoma compared to the normal counterpart. The antigen was also detected in the medium of various human cancer cells and meconium. However, the antigen in the sera, medium, meconium, and cancer tissue seemed to be associated with glycoprotein or lipoprotein, because most of the antigen activity was eluted in the void volume fraction on high-performance liquid chromatography with a gel filtration column.
 ...
PMID:Detection of patients with cancer by monoclonal antibody directed to lactoneotetraosylceramide (paragloboside). 334 24

A monoclonal antibody, MH-A6, was produced by immunization with a human gastric cancer cell line, MKN 74, treated with neuraminidase. The antigen defined by the monoclonal antibody was detected on various tumor tissues and a limited number of normal tissues in immunoperoxidase assay, and the expression of MH-A6 antigen was not influenced by neuraminidase treatment except for some cases of tumor tissues. Interestingly, neuraminidase treatment enhanced binding of the antibody on some adenocarcinomas, but diminished binding of the antibody on squamous cell carcinomas. Both treatment of the immunizing tissues with trypsin and periodic acid diminished binding of the antibody. In isolation of MH-A6 antigen from MKN 74 cells by the monoclonal antibody coupled-affinity column, the epitope exists on molecules with molecular weights of 30,000 and 72,000, and with an acidic pH range in two-dimensional electrophoresis. CEA and CA 19-9 activities were not detected in purified MH-A6 antigen by solid-phase radioimmunoassay, and the reactivity of the MH-A6 antibody with CEA and CA 19-9 was not detected in enzyme-linked immunosorbent assay. Hemagglutination observed between erythrocytes (Lewisa, Lewisb, or NE-treated) and anti-Lewisa, anti-Lewisb sera, or anti-T-agglutinin (peanut lectin), respectively, was not inhibited by MH-A6 antigen. The results suggest that MH-A6 antigen is a tumor-associated antigen, probably glycoprotein, and different from CEA, CA 19-9, Lewisa, Lewisb, and Thomsen-Friedreich (T) antigen.
 ...
PMID:Tumor-associated antigen defined by a monoclonal antibody against neuraminidase-treated human cancer cells. 342 53

DU-PAN-2 is a high-molecular-weight glycoprotein defined by a murine monoclonal antibody (MAb) against a pancreatic ductal adenocarcinoma cell line. In order to evaluate the usefulness of this antigen as a tumor marker, we determined the serum level of the antigen by competitive inhibition radioimmunoassay in sera from 139 patients with various malignant tumors, chiefly digestive cancers, 98 patients with different benign diseases and 11 healthy subjects. Values in the healthy subjects were less than 100 U/ml. Levels above 100 U/ml were frequently observed in sera from benign diseases, but levels above 400 U/ml were found in only 6 of the patients with benign diseases. In contrast, levels exceeding 400 U/ml were detected in 72% of patients with pancreatic cancer, 44% of patients with hepatocellular cancer and 40% of patients with biliary tract cancer. The positivity was low in other cancers such as gastric cancer (19%) and colorectal cancer (7%). Serum levels of CEA and CA 19-9 were also determined in cancer patients. Among the pancreatic cancer patients studied, values above 400 U/ml were found in 5 of the 8 CEA-negative patients (less than 5 ng/ml) and 2 of the 3 CA 19-9 negative patients (less than 37 U/ml). These results indicate that determination of the serum DU-PAN-2 can aid in serological diagnosis of cancer of the digestive tract, more particularly of the pancreas.
 ...
PMID:Measurement of a pancreatic cancer-associated antigen (DU-PAN-2) detected by a monoclonal antibody in sera of patients with digestive cancers. 345 70

Two monoclonal antibodies antitumor-associated antigens, B1.1 and B72.3, have been used with the immunoperoxidase technique on tissue sections to study gastric carcinomas, dysplasia, intestinal metaplasia, and adenomas. B1.1 reacts with carcinoembryonic antigen (CEA); B72.3 reacts with a 220-400 kd glycoprotein present in colon, breast, and other carcinomas. CEA was found in 89% (34 of 38) and B72.3 antigen in 92% (35 of 38) of carcinomas. In half of these more than 50% of tumor cells were positive. The normal epithelium was usually negative or sporadically positive in a few cells. In dysplastic areas and adenomas the number of cells that were positive for the two antigens was greater than in normal epithelium and smaller than in carcinomas. In intestinal metaplasia B72.3 antigen was almost always present, whereas CEA was sometimes undetectable. Both the antigens proved to be good markers of neoplastic versus normal cells. The presence of B72.3 antigen in addition to CEA in dysplasia, adenomas, and intestinal metaplasia adds further evidence of their close relationship with gastric cancer.
 ...
PMID:Distribution of two tumor-associated antigens in gastric lesions as detected by two monoclonal antibodies on tissue sections. 406 40

Pregnancy-associated alpha 2-glycoprotein (alpha 2-PAG) levels were measured in human sera by a modification of Laurell's electroimmunoassay using rabbit anti-alpha 2-PAG serum. Sera were obtained from healthy controls (32 males and 46 females), patients with benign breast diseases (55 cases), and patients with breast (82 cases), gastric (89 cases), or colorectal (22 cases) cancers. In healthy controls, the mean alpha 2-PAG value for females was higher than that for males (p less than 0.05), so alpha 2-PAG values for males and females were considered separately in this study. Serum alpha 2-PAG levels in patients with benign breast tumors were almost the same as those of controls. In patients with primary breast and gastric cancer, alpha 2-PAG levels were higher than those of controls (p less than 0.005) and tended to increase with progress of the disease. Raised alpha 2-PAG levels decreased in these patients after curative surgery. These results show that serum alpha 2-PAG is useful as a marker in both the initial diagnosis and follow-up of breast and gastric cancer. The reliability of alpha 2-PAG as a tumor-associated marker was reinforced by comparison of the positive rates of the three parameters alpha 2-PAG, carcinoembryonic antigen (CEA), and immunosuppressive acidic protein (IAP) in patients with breast and gastric cancer.
 ...
PMID:Significance of pregnancy-associated alpha 2-glycoprotein (alpha 2-PAG) in patients with breast, gastric and colorectal cancer. 617 10

Sera from 136 normal males and 33 members of families at high risk for colon cancer were tested for reactivity with six colon cancer cell lines by the protein A-mixed hemadsorption assay. Ninety-one sera had antibodies to colon cancer cell line HT-29. In 89 cases the antibodies were absorbed by human A and B erythrocytes or sheep erythrocytes. Antibodies in the remaining two sera, which were from sisters in the high-risk group, were not absorbed by red cells but could be absorbed by tumor cells expressing A or B blood-group determinants. Their reactivity was inhibited by some soluble blood-group glycoproteins. One serum (No. 4) was inhibited by A-active glycoproteins from human saliva and ovarian cyst fluids and from porcine mucosa, as well as by a polysaccharide derived from gastric cancer; it has an anti-A-like specificity. The other serum (No. 6) was inhibited by A and B glycoproteins, by a blood group precursor glycoprotein and by the same gastric cancer polysaccharide; it seems to have a wider specificity directed towards both A- and B-like structures. It is not known what caused production of these antibodies but it may be significant that they occurred in members of a family at high risk for developing colon cancer.
 ...
PMID:Natural antibodies in human sera directed against blood-group-related determinants expressed on colon cancer cells. 619 1

The mechanisms of action of, and resistance to, important anticancer agents are briefly described. Their selective toxicity is considerably high, and is chiefly due to the distribution and metabolism in the body. The selective toxicity of some DNA-binding drugs may be attributed to the structural difference of DNA, nucleosome and/or chromatin between neoplastic and normal cells. Some studies of reducing side effects are summarized. In our laboratory, we are studying drug-resistance and metastasis of tumor cells. Since the mechanism of natural resistance of gastric cancer, pulmonary cancer, and other refractory cancers may be related to acquired resistance of leukemia, studies on new agents against drug-resistant tumor cells are important. In our laboratory, we have selected cell sublines of murine T-lymphoblastoma L5178Y for resistance to adriamycin (ADM), aclarubicin (ACR) or bleomycin (BLM), and have observed that the resistance is attributed to decreased influx and increased efflux of the antibiotic, resulting in lowered retention of the drug in the cells. Each resistant subline shows a characteristic cross-resistant pattern, suggesting that membrane alteration involved differs each other. We have also found that glycoprotein-synthesizing activity and alkaline phosphodiesterase activity of plasma membrane are higher in the three resistant sublines than in the parental cell line. We obtained a number of hybridomas producing antibodies to plasma membrane of an ACR-resistant subline of L5178Y cells. Among the syngeneic monoclonal antibodies, one was found by agglutination tests to react with the ACR-resistant cell line, but not significantly with the parental and ADM-, BLM-and MCR-resistant cell lines. Fluorographs of [14C] leucine-labeled ACR-resistant cells demonstrates two protein bands of 230 K and 20 K daltons, which are precipitated by the monoclonal antibody. The former seems to be specific to the ACR-resistant cells. Based on the results so far obtained, the 230 K protein may be related to the drug resistance and may be TATA (tumor-associated transplantation antigen). The results suggest that isolation of drug-resistant neoplastic cells is a novel method of finding TATA.
 ...
PMID:[Mechanism of action and resistance of antineoplastic agents]. 619 71


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>