Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0272170 (SDS)
 50,377 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cell surface glycoproteins were isolated from the lysates of 125I-labeled normal human mammary epithelial cells (NHMEC) and from the human breast carcinoma cell line MCF-7, of blood-group O phenotype, by affinity chromatography on Griffonia simplicifolia I lectin-Sepharose. Specific elution of glycoproteins from the column with methyl alpha-D-galactoside suggests the presence of alpha-D-galactosyl groups on these moieties. SDS-PAGE analysis of isolated glycoproteins revealed both quantitative and qualitative differences between glycoproteins from normal and malignant cells. Three major glycoproteins of Mr 180 kDa, 85 kDa and the 44 kDa were obtained from MCF-7 cells. The 180-kDa glycoprotein was absent in NHMEC and the 44-kDa glycoprotein was very weakly expressed in these cells. The only glycoprotein which was found in almost equal amount in the lysate from both normal and malignant cells was the 85-kDa glycoprotein. These results indicate differences between normal human mammary epithelial cells and one kind of malignant human mammary epithelial cells, in the expression of glycoproteins containing alpha-D-galactosyl groups, irrespective of blood-group phenotype; they also demonstrate that alpha-D-galactosyl group are expressed in a very restrictive manner on the surface of this tumor cell line.
Cancer Lett 1991 Oct
PMID:Differential expression of glycoproteins containing alpha-D-galactosyl groups on normal human breast epithelial cells and MCF-7 human breast carcinoma cells. 191 27

A new cell line (LC-1/sq) of human lung squamous-cell carcinoma was established from a surgically resected specimen of primary lung cancer. Upon continuous propagation in serum-free culture medium, it secreted trypsin inhibitors into the conditioned medium. The major fraction of the trypsin inhibitor (T1-1) was purified to apparent homogeneity by anion-exchange and gel-filtration high-performance liquid chromatography (HPLC) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) followed by transblotting to Immobilon. T1-1 effectively inhibited trypsin. Chymotrypsin, plasmin and kallikrein were inhibited to a lesser extent, but urokinase-type plasminogen activator, elastase, thrombin and papain were not inhibited. The activity of T1-1 was acid-stable and heat-resistant, and its molecular weight was 115 kDa by SDS-PAGE. It exhibited single NH2-terminal sequence, and its first 20 NH2-terminal amino-acid residues were identical with those of protease nexin-II (PN-II)/amyloid beta-protein precursor (APP). These characteristics of T1-1 suggest that the major trypsin inhibitor secreted by LC-1/sq is indistinguishable from PN-II/APP. LC-1/sq is the first lung squamous carcinoma cell line that secretes functionally active trypsin inhibitor, PN-II/APP, in vitro and is useful for studying its biological significance in malignant tumor.
Int J Cancer 1991 Sep 30
PMID:Establishment of a new human cancer cell line secreting protease nexin-II/amyloid beta protein precursor derived from squamous-cell carcinoma of lung. 191 42

A novel 21-kDa protein (p21) was isolated from auto-immune complexes, found in sera of 14 patients with malignant urogenital tumors and isolated on Protein A-Sepharose. Isolated complexes were analyzed in 15% polyacrylamide-SDS minigels. After staining with Coomassie blue R, the bands were scanned with a clinical densitometer. The level of p21 in sera of cancer patients was 3 times higher than that found in normal individuals. An attempt was made to correlate consecutive levels of p21 in the sera of these cancer patients with the clinical course. In 4 cases a significant decrease (57-75%) in the level of p21 was observed in parallel with response to treatment. In 9 of 10 cases where no response or tumor progression was observed, the relative abundance of p21 increased or remained unchanged. Thus, the level of p21 was indicative of progression or regression of the disease in 13 out of 14 patients. Similar high levels of p21 in sera were also found in 22 patients with benign hyperplasia of prostate. The p21 protein was not immunoreactive with known anti-ras antibodies such as Y13-259, 142-24E05 and anti-rap1. Partial amino acid analysis of this protein showed no complete homology to any known protein, but a partial homology to known bacterial proteins involved in DNA replication or transcription was observed. Monitoring of the novel p21 levels before and after treatment may be useful in follow-up of cancer patients, providing evidence of response to treatment.
Int J Cancer 1991 Dec 02
PMID:A novel 21-kDa protein as a serum marker for benign and malignant urogenital tumors: preliminary communication. 195 89

Monoclonal antibody (MAb) D612 recognizes an antigen expressed on the cell surface of normal and malignant gastrointestinal epithelium. It is a murine IgG2a/kappa which has been previously shown to mediate killing of human colon carcinoma cells using human effector cells (which could be enhanced in the presence of interleukin-2). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analyses of MAb D612 immunoprecipitates of extracts of L-[35S]methionine-, L-[3H]leucine-, and D-[3H]glucosamine-labeled human colon carcinoma cells showed that the D612 antigen is a Mr 48,000 glycoprotein. Similar estimates of molecular mass were obtained from SDS-PAGE analyses of MAb D612 immuno-precipitates of radioiodinated extracts of surgically resected colon carcinoma and adjacent normal colonic mucosa. D612 antigen was not detectable in immunoprecipitates of supernatant media from radiolabeled cell cultures, suggesting that the antigen is not readily shed from the surface of cultured cells. The D612 antigen was shown to be clearly distinct from previously described gastrointestinal carcinoma-associated glycoproteins: the D612 antigen shows a migration pattern of SDS-PAGE distinct from those of the antigens recognized by MAbs KS1/4 and GA733, and reciprocal immunodepletion analyses of D-[3H]glucosamine-labeled colon carcinoma cells utilizing MAbs D612 and GA733 revealed no cross-reactivity between these antibodies. Similarly, competitive binding studies between MAbs 17-1A and KS1/4 and MAb D612 revealed no similarity between the epitopes recognized by MAb D612 and MAbs 17-1A and KS1/4. MAbs D612 and 17-1A were also titered in immunoperoxidase staining assays on serial frozen sections of normal and malignant colon. MAb D612 showed a higher titer of immunostaining reactivity with both normal and malignant colon than did MAb 17-1A. MAb D612 showed roughly equivalent immunostaining titers against normal and malignant colon; whereas MAb 17-1A showed higher titer of immunostaining reactivity against the normal colon tissue than against the malignant colon. Flow cytometric analysis of phosphatidylinositol-specific phospholipase C-treated colon carcinoma cells revealed no loss of D612 antigen from the cell surface, suggesting that the mechanisms of attachment of the D612 antigen to the cell surface does not involve linkage to a phosphatidylinositol glycan.(ABSTRACT TRUNCATED AT 400 WORDS)
Cancer Res 1991 Feb 01
PMID:Characterization of the colorectal carcinoma-associated antigen defined by monoclonal antibody D612. 198 33

Recombinant human tumor necrosis factor-alpha (TNF-alpha) is a macrophage-derived, non-glycosylated (17 kDa) peptide that has a remarkably broad range of biological and immunological effects including antiviral action and cytotoxic and cytostatic effects. TNF-alpha was coupled to murine antibody ZME-018, which recognizes a 240 kDa glycoprotein present on over 80% of melanoma cells. The crosslinking was accomplished using the heterobifunctional crosslinking reagent, N-succimindyl 3-(2-pyridyldithio)proprionate (SPDP). After purification on gel-permeation and affinity columns, the resulting eluate was analyzed by non-reducing SDS-PAGE, which confirmed that the product was a mixture of ZME-018 coupled to one or two TNF-alpha molecules. The ZME-TNF conjugate was titered against murine L-929 cells to demonstrate the presence of active TNF. ELISA of the conjugate against target BRO human melanoma cells or non-target T-24 cells demonstrated specific binding only to target cells. Melanoma BRO cells were killed by the immunoconjugate (IC50 of 10 units/mL), whereas native TNF-alpha had no effect at concentrations greater than 50,000 units/mL. The immunoconjugate and TNF-alpha were inactive against T-24 non-target cells. These studies suggest that the sensitivity of cells to TNF was dramatically augmented by specific antibody mediated delivery to tumor cells.
Cancer Commun 1991 Jan
PMID:Antibody-mediated delivery of tumor necrosis factor (TNF-alpha): improvement of cytotoxicity and reduction of cellular resistance. 198 45

A total of 72 human leukemia-lymphoma cell lines were studied for reactivity with the monoclonal antibody (MAb) A7, an anti-human colon-cancer-cell-associated antigen reagent, by indirect membrane immunofluorescence. Nine of the 72 cell lines expressed the antigen recognized by A7 MAb. Five of the 34 T-cell lines, 2 of the 21 B-cell lines, and 2 of the 3 non-lymphoid-non-myeloid cell lines were reactive with A7 MAb. By means of SDS-PAGE and immunoblotting, the antigens isolated from both colon cancer cell lines (WiDr, SW1116 and LoVo) and leukemia cell lines (A3/KAWAKAMI, H9, RPMI 8226 and SPI-801) showed an identical MW of 42-43 kDa. The non-glycosylated antigen recognized by A7 MAb, which was expressed on both the colon cancer line (SW1116) and the leukemia line (H9) in the presence of tunicamycin, also showed an identical MW of 36 kDa. However, the quantity of the antigen in the leukemia cells was significantly lower than in the colon cancer cells. Although expression of this colon-cancer-associated antigen in the non-colon cancer cells is real, the significant expression of this antigen in colon-cancer cells makes it useful for clinical monitoring of colon cancer patients.
Int J Cancer 1991 Feb 01
PMID:Identification and characterization of a colon-cancer-associated antigen expressed on leukemia-lymphoma cell lines. 199 51

Previous studies have indicated that cyst fluid of ovarian tumors contains 2 trypsinogen isoenzymes, called tumor-associated trypsinogen-I (TAT-I) and trypsinogen-2 (TAT-2), the levels of which correlate with the degree of malignancy of the tumors. In addition, these cyst fluids contain large amounts of tumor-associated trypsin inhibitor (TATI), which is also expressed in many other human tumors. In the present study we examined the production of TAT-I, TAT-2 and TATI in 9 established tumor-cell lines. TAT-2 was produced by 5 cell lines. Its concentration in the conditioned medium of COLO 205 colon adenocarcinoma cells, K-562 erythroleukemia cells and fibrosarcoma cell lines HT 1080, 8387 and A 9733 was 460 micrograms/l, 9.8 micrograms/l, 21 micrograms/l, 8.8 micrograms/l and 0.24 micrograms/l, respectively. TAT-I was detectable in the conditioned medium of COLO 205 and HT 1080 cells at concentrations of 64 micrograms/l and 0.5 micrograms/l, respectively. TATI was detected only in the media of COLO 205 cells at a concentration of 23 micrograms/l. TAT-2 zymogen was purified from the conditioned medium of COLO 205 and HT 1080 cells by immunoaffinity chromatography. According to its aminoterminal amino acid sequence, a molecular mass of 28 kDa by SDS-PAGE, elution pattern in ion-exchange chromatography and ability to be activated by enteropeptidase, the zymogen is identical to that previously isolated from cyst fluid of ovarian tumors. In addition, we found that TAT-2 secretion could be down-regulated by dexamethasone in HT 1080 cells but not in COLO 205 cells. The abundant production of TAT-2 isoenzyme in different cancer cell lines suggests that it could contribute to the increased proteolytic activity of many human tumors.
Int J Cancer 1991 Feb 20
PMID:Human colon carcinoma, fibrosarcoma and leukemia cell lines produce tumor-associated trypsinogen. 199 87

Fluorescent lectin binding to cell surfaces was quantitatively analysed by flow cytometry on mortal human breast epithelial cells MCF-10M, the immortalized cell line MCF-10A derived from MCF-10M and sublines of MCF-10A transfected with the neomycin resistance gene (MCF-10Aneo), the c-Ha-ras protooncogene (MCF-10AneoN), or transfected and transformed with the c-Ha-ras activated oncogene (MCF-10AneoT). Immortal MCF-10A cells bound 10-fold more peanut agglutinin (PNA) and soy bean agglutinin (SBA) than did MCF-10M cells. Transformed MCF-10AneoT cells bound approximately ten times more PNA than did non-transformed cells transfected with protooncogene (MCF-10AneoN). Treatment of the transfectants with neuraminidase abrogated the differences in PNA-binding and reduced the differences in SBA binding. SDS-PAGE separation of PNA binding glycoproteins revealed different patterns for all MCF-10A derived sublines.
Cancer Lett 1991 Apr
PMID:Cell surface glycosylation changes accompanying immortalization and transformation of normal human mammary epithelial cells. 202 77

Testing of a panel of cultured human melanoma cells with radiolabelled anti-HLA-class-I monoclonal antibodies (MAbs) in a binding assay has shown lack of reactivity of FO-I and SK-MEL-33 cells and low reactivity of SK-MEK-19 cells. SDS-PAGE analysis of the components immunoprecipitated from the 3 intrinsically radiolabelled melanoma cell lines by antibodies to the 2 subunits of HLA-class-I antigens has not detected beta 2-mu in the immunoprecipitates from melanoma cells FO-I and SK-MEL-33 and only a low level of HLA-class-I heavy chain in the immunoprecipitate from SK-MEL-19 cells. Northern blotting analysis with probes specific for HLA-class-I heavy chain and for beta 2-mu indicates that the abnormalities in HLA-class-I-antigen expression reflects a defect at the transcriptional level in FO-I cells and at the post-transcriptional level in SK-MEL-19 and in SK-MEL-33 cells. FO-I, SK-MEL-19 and SK-MEL-33 cells represent useful models to analyze the molecular mechanisms underlying the loss of HLA-class-I-antigen expression which is often associated with malignant transformation of melanocytes and to characterize the role of HLA-class-I antigens in the biology of melanoma cells and in their interactions with effector cells.
Int J Cancer Suppl 1991
PMID:Molecular abnormalities in the expression of HLA class-I antigens by melanoma cells. 206 75

The expression of blood-group-related antigens (BGRAs) in experimental primary pancreatic cancer induced by N-nitrosobis(2-oxopropyl)amine (BOP) treatment of Syrian hamsters and homologous subcutaneous transplants of this primary cancer in the cell line, PC-1, established from the primary cancer and intrapancreatic transplanted PC-1 cells were studied by histochemical and biochemical methods. Human primary pancreatic cancer; the human pancreatic cancer cell line, HPAF; and its subclones, CD11 and CD18, also were studied on a comparative basis. Histochemical analysis of BGRAs demonstrated that A, B, H, Leb, Lex, Ley, and T antigen were expressed both in vivo and in vitro in hamster and human materials in similar patterns. However, Lea, CA 19-9 and sialylated Tn antigens were not found in hamster-derived tissues. SDS-PAGE and Western blotting procedures using anti-A antigen revealed similar major bands in the membrane fractions of both human and hamster pancreatic cells between 97 and 200 kdalton. Among other human pancreatic cancer-associated antigens, TAG-72, CA 125, and 17-1A were detected immuno-histochemically in the hamster tumors both in vivo and in vitro, in a pattern similar to that seen in human pancreatic cancer. Tumor antigen DU-PAN-2, associated with human pancreatic cancer, was found infrequently in hamster pancreatic cancer specimens. These results indicate that the experimental hamster pancreatic cancer model provides a unique tool for investigating antigenicity of pancreatic cancer, particularly in relation to diagnosis and therapy.
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PMID:Comparative studies on expression of tumor-associated antigens in human and induced pancreatic cancer in Syrian hamsters. 208 32


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