Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0684249 (lung carcinoma)
 23,830 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The surface glycoprotein gp43, a highly immunogenic component of Paracoccidioides brasiliensis, is used in the serodiagnosis of paracoccidioidomycosis (PCM) and has recently been shown to specifically bind the extracellular matrix protein laminin. Binding to laminin induces the increased adhesion of the fungus to epithelial cells; a hamster testicle infection model has shown that the gp43-dependent binding of fungal cells to laminin enhances their pathogenicity in vivo. We report on the production and characterization of 12 monoclonal antibodies against the gp43 that recognize peptide sequences in the molecule detecting at least three different epitopes as well as different isoforms of this antigen. MAbs interfered in the fungal pathogenicity in vivo either by inhibiting or enhancing granuloma formation and tissue destruction. Results suggest that P. brasiliensis propagules may start infection in man by strongly adhering to human lung cells. Thus, laminin-mediated fungal adhesion to human lung carcinoma (A549) cells was much more intense than to Madin-Darby canine kidney cells (MDCK), indicating differences in binding affinity. Subsequent growth of fungi bound to the lung cells could induce the granulomatous inflammatory reaction characteristic of PCM. Both steps are greatly stimulated by laminin binding in infective cells expressing gp43.
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PMID:Monoclonal antibodies against the 43,000 Da glycoprotein from Paracoccidioides brasiliensis modulate laminin-mediated fungal adhesion to epithelial cells and pathogenesis. 898 52

Expression of tenascin, an extracellular matrix glycoprotein, was measured in glioma cell lines using a newly established enzyme immunoassay. Secreted tenascin was found at concentrations greater than 800 ng/ml in eight of 14 glioma, three small cell lung carcinoma, two melanoma, and one sarcoma cell lines. The remaining six glioma and other carcinoma cell lines, and cell lines originating from normal tissues demonstrated low levels or no secretion into the supernatant. The glioma cell line, U-251-MG nu/nu, which has almost 100% transplantability in nude mice, had the highest expression level of tenascin among the glioma cell lines examined. Even low secretor glioma cell lines released high concentrations of tenascin, detectable by assaying the NP-40 solubilized cell lysates. Flow cytometric analysis revealed that tenascin was located on both the cell surface and primarily in the cytoplasm of glioma cells. When the glioma cell lines were exposed to tumor necrosis factor-alpha (TNF-alpha), levels of secreted tenascin increased between 36% and 380%, whereas transforming growth factor-beta induced only minimal changes. These results suggest that glioma cell lines may be classified according to the degree of tenascin secretion/expression: high secretor type, low secretor type, and non-expressing type. The increase in tenascin secretion by TNF-alpha suggests that the expression of tenascin in glioma growth and development may be mediated through a cytokine network.
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PMID:Enzyme immunoassay of glioma cell tenascin secretion and augmentation by tumor necrosis factor-alpha. 918 37

Chromogranin A (CgA) is gaining acceptance as a serum marker of neuroendocrine tumors. Its specificity in differentiating between neuroendocrine and nonneuroendocrine tumors, its sensitivity to detect small tumors, and its clinical value, compared with other neuroendocrine markers, have not clearly been defined, however. The objectives of this study were to evaluate the clinical usefulness of CgA as neuroendocrine serum marker. Serum levels of CgA, neuron-specific enolase (NSE), and the alpha-subunit of glycoprotein hormones (alpha-SU) were determined in 211 patients with neuroendocrine tumors and 180 control subjects with nonendocrine tumors. The concentrations of CgA, NSE, and alpha-SU were elevated in 50%, 43%, and 24% of patients with neuroendocrine tumors, respectively. Serum CgA was most frequently increased in subjects with gastrinomas (100%), pheochromocytomas (89%), carcinoid tumors (80%), nonfunctioning tumors of the endocrine pancreas (69%), and medullary thyroid carcinomas (50%). The highest levels were observed in subjects with carcinoid tumors. NSE was most frequently elevated in patients with small cell lung carcinoma (74%), and alpha-SU was most frequently elevated in patients with carcinoid tumors (39%). Most subjects with elevated alpha-SU levels also had elevated CgA concentrations. A significant positive relationship was demonstrated between the tumor load and serum CgA levels (P < 0.01, by chi 2 test). Elevated concentrations of CgA, NSE, and alpha-SU were present in, respectively, 7%, 35%, and 15% of control subjects. Markedly elevated serum levels of CgA, exceeding 300 micrograms/L, were observed in only 2% of control patients (n = 3) compared to 40% of patients with neuroendocrine tumors (n = 76). We conclude that CgA is the best general neuroendocrine serum marker available. It has the highest specificity for the detection of neuroendocrine tumors compared to the other neuroendocrine markers, NSE and alpha-SU. Elevated levels are strongly correlated with tumor volume; therefore, small tumors may go undetected. Although its specificity cannot compete with that of the specific hormonal secretion products of most neuroendocrine tumors, it can have useful clinical applications in subjects with neuroendocrine tumors for whom either no marker is available or the marker is inconvenient for routine clinical use.
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PMID:Chromogranin A as serum marker for neuroendocrine neoplasia: comparison with neuron-specific enolase and the alpha-subunit of glycoprotein hormones. 925 44

Lung Cancer Associated Protein (LCAP) is a high molecular weight glycoprotein defined by the monoclonal antibody (MAb) DF-L1 prepared against a primary adenocarcinoma of the lung. Previous studies have demonstrated that LCAP circulates at elevated levels in patients with lung cancer. However, a suitable assay for monitoring LCAP levels has not been available. The present work describes the development of a double-determinant LCAP assay using MAb TRD-L1 as the capture antibody and MAb DF-L1 as the tracer. In 60 normal subjects, the mean LCAP level was 4.8 U/ml with 2 (3.3%) subjects having values > 12 U/ml (mean + 2SDS). By contrast, 37 of 67 (55.2%) patients with lung cancer had LCAP levels > 12 U/ml. Moreover, only 14 of 203 (6.9%) patients with benign lung disease had elevated levels. LCAP levels were most commonly elevated (62.7%) in patients with adenocarcinoma of the lung and with advanced disease. These results indicate that LCAP as detected by MAb TRD-L1 is a potentially useful marker for the evaluation of patients with lung cancer.
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PMID:Detection of the circulating lung cancer marker LCAP with a new monoclonal antibody TRD-L1. 934 32

Stem cell factor (SCF) is a glycoprotein growth factor produced by marrow stromal cells that acts after binding to its specific surface receptor, which is the protein encoded by the protooncogene c-kit. SCF synergizes with specific lineage factors in promoting the proliferation of primitive hematopoietic progenitors, and has been administered to expand the pool of these progenitors in cancer patients treated with high-dose chemotherapy. SCF and its c-kit receptor are expressed by some tumor cells, including myeloid leukemia, breast carcinoma, small cell lung carcinoma, melanoma, gynecological tumors, and testicular germ cell tumors. Previous studies of SCF in neuroblastoma have produced conflicting conclusions. To explore the role of SCF in neuroblastoma, we studied five neuroblastoma lines (IMR-5, SK-N-SH, SK-N-BE, AF8, and SJ-N-KP) and the neuroepithelioma line CHP-100. All lines expressed mRNA for c-kit and c-kit protein at low intensity as measured by flow cytometry, and secreted SCF in medium culture as shown by ELISA. Exogenous SCF did not modify 3H thymidine uptake in the neuroblastoma and neuroepithelioma cell lines. After 6 days' culture in the presence of anti-c-kit, the number of viable neuroblastoma cells was significantly lower than the control, and terminal deoxynucleotidyl transferase assay showed a substantial increase of apoptotic cells: The percentage of positive cells was 1-3% in the control lines, whereas in the presence of anti c-kit it varied from 29% of SK-N-BE to 92% of CHP-100. After 9 days' culture in the presence of anti-c-kit, no viable cells were detectable. These data indicate that SCF is produced by some neuroblastoma cell lines via an autocrine loop to protect them from apoptosis.
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PMID:Stem cell factor suppresses apoptosis in neuroblastoma cell lines. 935 69

The study of tumour markers in lung cancer has focused mainly on serum-based analysis. The controversy about carcinoembryonic antigen (CEA), pregnancy specific glycoprotein 1 (SP1) and beta human chorionic gonadotropin (betahCG) production in lung carcinoma has been reported in several studies. The aims of this study were: to explore an expression of CEA, SP1 and betahCG in various histological types of lung carcinoma with respect to the grade of differentiation; and to define the relationship between tumour marker expression and serum marker concentration. Ninety two lung tumours (75 non-small cell carcinomas (NSCLC) and 17 small cell lung carcinomas (SCLC)) entered the study. Tumour marker expression was compared with the serum levels of CEA, SP1 and betahCG in 57 patients (pts) with NSCLC and four pts with SCLC. Positive immunostaining of CEA and SP1 was observed in 87% NSCLC, and betahCG was found in 24% NSCLC. In the SCLC group positive staining showed in 29% of tumours, SP1 in 51% and betahCG in 18%. Positive CEA expression ranged from 50-100% within the carcinomatous cell population (pcp) and was more characteristic for well and moderately differentiated adenocarcinomas. This finding was in contrast to squamous cell carcinomas, where the majority of tumours expressed CEA in 1-50% pcp. A significant negative correlation was noticed for adenocarcinoma between tumour expression and grade of histological differentiation for CEA (P < 0.001) and SP1 (P = 0.023). Results were not significant for squamous carcinoma. Significant differences of serum CEA concentration were noticed between adenocarcinoma and squamous carcinoma (P = 0.003). In addition, a statistically significant relation was found between serum CEA concentration and an early (I + II) and advanced (IIIa + IIIb + IV) stage of NSCLC (P = 0.031). A significant correlation was noticed when serum CEA and tumour CEA expression was compared for NSCLC (P < 0.001), and for serum betahCG and tumour betahCG (P = 0.019).
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PMID:Expression of CEA and trophoblastic cell markers by lung carcinoma in association with histological characteristics and serum marker levels. 951 51

Transferrin is a serum glycoprotein involved in iron transport. Transferrin acts also in cell growth regulation through membrane receptors. The number of transferrin receptors is increased in tumor and other rapidly dividing cells. This renders transferrin suitable for use in cytotoxic drugs targetting tumor cells. Paclitaxel was derivatized on 2' carbon and coupled with trasferrin using glutaraldehyde. The cytotoxicity of the conjugate was evaluated on small cell carcinoma of the lung cell line (H69). As compared to paclitaxel, the conjugate exhibited a slight decrease in cytotoxicity.
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PMID:In vitro cytotoxicity of paclitaxel-transferrin conjugate on H69 cells. 976 72

Thrombospondin (TSP) is a Mr 450,000 multifunctional matrix glycoprotein that interferes with tumor growth, angiogenesis, and metastasis. It has recently been shown that TSP expression is enhanced by the product of the p53 gene and that a down-regulation of TSP may be observed when alterations of the p53 protein occur. Moreover, a number of studies have demonstrated a regulatory activity of p53 on human vascular endothelial growth factor (VEGF), although additional investigations will be necessary to understand their relationship. In non-small cell lung carcinoma (NSCLC), neoangiogenesis, p53 alterations, and VEGF expression seem to have meaningful implications in the development and progression of this type of cancer. The aim of this study is to identify and quantitate TSP I and TSP II mRNA in NSCLCs with respect to p53 alterations, angiogenic growth factor expression, and microvascular density. A series of 24 cases of NSCLC were analyzed. Eleven of 24 of the cases were positive for TSP II mRNA, whereas 8 of 24 showed TSP I mRNA expression. A significant inverse association was found between TSP I mRNA and fibroblast growth factor (FGF) protein expression (P = 0.00001). Tumors with low FGF protein expression (< or = 40% of positive cells) presented a number of TSP I cDNA molecules, significantly higher than tumors expressing high levels of FGF protein. No association was found between TSP mRNA expression and other angiogenic growth factors (i.e., VEGF) or tumoral neovascularization. On the contrary, tumors with high levels of FGF showed a higher number of microvessels (P = 0.05). By PCR-single-strand conformational polymorphism analysis, we observed aberrations of the p53 gene in 19 of the 24 tumor samples. No association was found between p53 alterations and TSP mRNA expression. Instead, an interestingly significant association was found between the presence of p53 mutations and high VEGF protein expression (P = 0.01) and neovascularization (P = 0.03). Highly vascularized tumors showed higher VEGF protein expression (r = 0.45; P = 0.02). These data support the concept that in NSCLC, p53 exerts an important role in the control of neoangiogenesis. This influence is probably mediated by VEGF. The inverse association we found between TSP I and basic FGF suggests a different role of TSP I and TSP II in the angiogenic "switch," supporting the hypothesis that especially TSP I may have a significant function in tumor angiogenesis.
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PMID:Thrombospondins I and II messenger RNA expression in lung carcinoma: relationship with p53 alterations, angiogenic growth factors, and vascular density. 991 14

Progranulin is a 593-amino acid glycoprotein, the mRNA of which is expressed by many epithelial cells both in vitro and in vivo, but the biological significance of this expression is unclear. In this study, we demonstrate that overexpression of the progranulin gene in SW-13 adrenal carcinoma cells and MDCK nontransformed renal epithelia results in the transfection-specific secretion of progranulin, acquired clonogenicity in semisolid agar, and increased mitosis in monolayer culture, whereas diminution of progranulin gene expression impairs growth of these cells. Purified recombinant progranulin reproduces the effects of forced progranulin expression, being clonogenic in soft agar and mitogenic in monolayer culture to SW-13 and MDCK cells and other epithelia of various origins such as GPC16 colonic epithelium and A549 lung carcinoma cells. Progranulin overproduction in SW-13 cells markedly increases its tumorigenicity in nude mice, demonstrating that it can regulate epithelial proliferation in vivo. We propose that the rate of growth for some epithelia, such as SW-13 and MDCK, is proportional to the level of intrinsic progranulin gene expression, and that elevated progranulin gene expression confers a transformed phenotype on epithelial cells including anchorage independence in vitro and growth as tumors in nude mice.
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PMID:Progranulin gene expression regulates epithelial cell growth and promotes tumor growth in vivo. 1039 69

Sialomucin complex (SMC/Muc4) is a heterodimeric glycoprotein complex consisting of a mucin subunit ascites sialoglycoprotein-1 (ASGP-1) and a transmembrane subunit (ASGP-2), which is aberrantly expressed on the surfaces of a variety of tumour cells. SMC is transcribed from a single gene, translated into a large polypeptide precursor, and further processed to yield the mature ASGP-1/ASGP-2 complex. SMC has complex spatial and temporal expression patterns in the normal rat, suggesting that it has complex regulatory mechanisms. A crude exon/intron map of the 5' regions of the SMC/Muc4 gene generated from clones isolated from a normal rat liver genomic DNA library reveals that this gene has a small first exon comprising the 5' untranslated region and signal peptide, followed by a large intron. The second exon appears to be large, comprising the 5' unique region and a large part (probably all) of the tandem repeat domain. This structure is strikingly similar to that reported for the human MUC4 gene. Using PCR-based DNA walking, 2.4 kb of the 5'-flanking region of the SMC/Muc4 gene was cloned and characterized. Promoter-pattern searches yielded multiple motifs commonly found in tissue-specific promoters. Reporter constructs generated from this 2.4 kb fragment demonstrate promoter activity in primary rat mammary epithelial cells (MEC), the human colon tumour cell line HCT-116, and the human lung carcinoma cell line NCI-H292, but not in COS-7 cells, suggesting epithelial cell specificity. Deletion constructs of this sequence transfected into rat MEC or HCT-116 cells demonstrate greatly varying levels of activity, suggesting that there are positive and negative, as well as tissue-specific, regulatory elements in this sequence. Taken together, these data suggest that the rat SMC/Muc4 promoter has been identified, that it is tissue- (epithelial cell-) specific, and that there are both positive and negative, as well as tissue-specific, regulatory elements in the sequence.
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PMID:Cloning and characterization of the 5' flanking region of the sialomucin complex/rat Muc4 gene: promoter activity in cultured cells. 1088 Mar 65


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