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

A butenolide compound (1E,3E,5E,7E)-5-hydroxy-4-(8-phenyl-1,3,5,7- octatetraenyl)-2(5H)-furanone (KNK-41), was shown to have strong anti-tumor activity. KNK-41 inhibited the proliferation of various kinds of human malignant tumor cells, such as HeLa (cervical carcinoma), HGC-27 (gastric cancer), PANC-1 (pancreatic cancer) and GOTO (neuroblastoma). Flow cytometric analysis indicated that KNK-41 caused an arrest in G0/G1 phase of the cell cycle. However, it scarcely affected DNA synthesis and the level of c-myc mRNA. These results suggest that the growth-inhibitory effect of KNK-41 is the result of G0/G1 arrest and not of the suppression of DNA synthesis and/or c-myc expression.
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PMID:Inhibitory effects of (1E,3E,5E,7E)-5-hydroxy-4-(8-phenyl-1,3,5,7- octatetraenyl)-2(5H)-furanone on proliferation of human malignant tumor cells. 157 90

Vasoactive intestinal polypeptide (VIP) is a gut neuroendocrine polypeptide that increases cyclic adenosine monophosphate (cAMP) production in cells with VIP receptors. Some gastrointestinal cancer cells possess functional receptors for VIP; however, the role of VIP in regulation of growth of gastric cancer cells has not been determined. The purpose of this study was to determine whether VIP and other agents that increase cAMP regulate growth of a human gastric cancer cell line (AGS) and whether these agents regulate expression of c-myc proto-oncogene, which is required for cell proliferation. We measured levels of cAMP by radioimmunoassay, and we used Northern blot analysis to examine c-myc messenger RNA expression. Cell-growth studies were carried out in media supplemented with 3% serum, and cells were counted with a Coulter counter. We found that VIP significantly increased cAMP production of AGS cells in a dose-dependent manner, whereas secretin, glucagon, and peptide histidine methionine (PHM) did not stimulate cAMP production. Exogenous cAMP (8-bromo-cAMP) inhibited AGS cell growth in a dose-dependent manner. VIP acted synergistically with either isobutylmethyl-xanthine or forskolin to inhibit AGS cell proliferation. The increased c-myc expression, which was induced by serum, was inhibited by simultaneous treatment with VIP and isobutylmethyl-xanthine. We have found that AGS cells have specific, functional VIP receptors (activation of which are negatively correlated with cell growth) and that the mechanism by which VIP acts to inhibit cell growth appears to be due, in part, to cAMP-dependent regulation of c-myc proto-oncogene expression.
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PMID:Vasoactive intestinal polypeptide inhibits c-myc expression and growth of human gastric carcinoma cells. 171 57

In an immunohistopathological study, we have used the specific monoclonal antibody myc 1-9E10 to the c-myc oncoprotein in 88 gastric carcinomas (22 gastric biopsies and 66 gastrectomies for cancer). Positive myc p62 immunoreactivity was shown in 48 (55%) cases with moderate or intense staining. The remaining 40 cases exhibited negative or equivocal staining. Normal stomach mucosa was generally nonreactive, with the exception of parietal cells. Elevated c-myc expression was not found to correlate with histological differentiation or in patients with metastases in one or more perigastric lymph nodes. A correlation was found between the level of c-myc expression and the stage of the disease, (p = 0.04); positive c-myc staining was found in 0/4 early gastric cancers and in 48/84 with advanced disease. Also, an association was found between the elevated c-myc expression and depth of invasion (p = 0.1; 0/4 mucosa and submucosa, 2/6 muscularis propria and 25/47 serosa). The c-myc monoclonal myc 1-9E10 may therefore be of use as a marker of advanced disease and depth of invasion in stomach cancer.
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PMID:Immunohistochemical analysis of the expression of the c-myc oncoprotein in human stomach cancers. 181 39

By analyzing c-myc specific fragments from white blood cell DNAs of 98 gastric cancer patients and 46 control subjects, we observed 6 unexpected patterns due to presence of a variant c-myc gene in addition to the normal gene. Restriction enzyme mapping indicated that the variant c-myc gene was the result of a 5' deletion including the first exon and part of the first intron. The deleted region, non-coding for the functional c-myc protein, contains sequences involved in the regulation of transcription. We therefore analyzed the c-myc mRNAs from a subject carrying the truncated gene and from a subject homozygous for the normal gene in Northern blotting experiments: the mRNAs were indistinguishable, both qualitatively and quantitatively. Family analysis demonstrated that the truncated gene is inherited in a Mendelian fashion. Population studies showed that the allele, both in patients and in control subjects, reaches a polymorphic frequency (2.1% for the whole sample) and that it is not associated with a risk of cancer.
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PMID:A 5'-truncated c-myc gene variant not associated with a risk of cancer. 191 60

In order to evaluate the relevance of protooncogene alterations in gastric cancer and to specifically relate these alterations to types and stages of the neoplasia, we studied oncogenes of possible interest in gastric tumors with different clinical parameters. Fifty DNAs from primary gastric adenocarcinoma were analyzed, by the Southern blotting technique, for the presence of amplification or rearrangements of seven different protooncogenes: c-myc, c-erbB2, c-Ki-ras, c-Ha-ras, c-N-ras, hst, and c-mos. All the tumors analyzed were histologically classified and staged. Amplification of the following genes was found: c-myc (2 of 50), hst (3 of 50), c-erbB2 (3 of 50), and c-Ki-ras (5 of 50). The simultaneous amplification of hst (3 cases), c-myc (1 of 3), or c-Ki-ras (2 of 3) was observed. Analysis of DNAs from atrophic and metaplastic gastric mucosa (which can be regarded as preneoplastic lesions) of the 10 patients showing gene amplification demonstrated that this was limited to neoplastic cells. Considering protooncogene amplification in general (i.e., involving different genes and occurring to different degrees) and clinical parameters of tumors, we found a statistically significant association between amplification and both tumor progression and presence of metastases. Therefore, at least for the genes analyzed, amplification is a relatively infrequent phenomenon and represents a late event in the temporal development of gastric cancer.
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PMID:Heterogeneous protooncogene amplification correlates with tumor progression and presence of metastases in gastric cancer patients. 225 24

Alteration of oncogene and loss of chromosomal heterozygosity are infrequent in human gastric carcinoma compared with those in other gastrointestinal carcinomas. Amplification of c-erbB-2 gene is observed in well differentiated adenocarcinoma, while sam gene is found in poorly differentiated adenocarcinoma or scirrhous carcinoma. sam gene, which was isolated from a gastric cancer cell line KATO-III by a DNA renaturation method, encodes tyrosine-specific protein kinase domain. A good correlation evidently exists between the synchronous expression of TGF alpha and ras p21 and biological malignancy of gastric carcinoma. c-myc and c-fos proteins are found not only in tumor cells but also in stromal cells including macrophages and fibroblast around the tumors. The prognosis of patients with c-myc p 62-positive stromal cells is significantly better than that of patient with p 62-negative stromal cells. Coamplification of the hst-1 gene and int-2 is observed in 50% of primary tumors and all metastatic tumors of esophageal carcinoma. PCR (polymerase chain reaction) technique seems to be useful for the detection of oncogene point mutation in human gastric carcinoma.
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PMID:[Oncogenes in human gastric carcinoma]. 254 46

c-erbB-2 oncogene has been reported to be frequently amplified in differentiated, tubular type of gastric cancer. Here we report a human gastric cancer which bore co-amplified c-myc and c-erbB-2 oncogenes: a portion of the amplified c-erbB-2 oncogene was found to be rearranged. Furthermore, c-myc and c-erbB-2 oncogenes were over-expressed in the tumor cells. In contrast to the previous reports, this gastric adenocarcinoma was classified as a poorly differentiated type, and was highly tumorigenic in nude mice. These results might suggest that activated c-myc and c-erbB-2 oncogenes co-operate and influence the malignant state of some gastric carcinomas.
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PMID:Co-amplification of c-myc and c-erbB-2 oncogenes in a poorly differentiated human gastric cancer. 257 9

A human primary gastric cancer tissue (adenocarcinoma II-III) was transplanted into nude mice (SWISS/DF. nu/nu). It has been transferred for 8 generations at 56 sites in 28 nude mice with transplantable rate of 100%. The transplanted tumor is designated as transplantable human primary gastric cancer-1 in nude mice (THPGC-1). The growth of THPGC-1 is rather rapid and the size of transplanted tumor reaches 1 cm2, 4-5 weeks after transfer. The morphology and histochemistry of the original tumor were retained well in the initial and serial transplanted tumors. THPGC-1 could secret carcinoembryonic antigen (CEA). After intravenous or intraperitoneal injection of 131I-antiCEA monoclonal antibody into the THPGC-1 bearing nude mice, the radiolabeled antibody was concentrated and localized in the tumor as shown by gamma-camera analysis. Similar pattern of lactate dehydrogenase isoenzyme was observed both in primary gastric cancer tissue and THPGC-1 tissue. Chromosomal examination revealed that THPGC-1 was human aneuploid ones. Southern blot analysis showed that the pattern of repetitive DNA bands and the structures of 28s, rDNA, c-H-ras and c-myc genes in THPGC-1 were identical to the original primary gastric cancer DNA. The results suggest that THPGC-1 be a reliable model for the research of the molecular biology of cancer cells and experimental gastric cancer diagnosis and treatment.
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PMID:[Biologic and molecular genetic properties of a transplantable human primary gastric cancer in nude mice]. 269 24

A human gastric signet ring cancer cell line (Mz-Sto-1) was established in tissue culture from the ascites fluid of a 54-year-old patient. The tumor cells growing in tissue culture exhibit the morphological characteristics of signet ring cells in phase contrast and transmission electron microscopy. Mz-Sto-1 cells grow as monolayer with a population doubling time of 28-36 hr during exponential growth phase and show a chromosome number between 72 and 74. In the cellular DNA of Mz-Sto-1 cells no amplification of 19 oncogenes studied is observed, c-myc included. Mz-Sto-1 cells secrete 150-250 ng CEA per 10(7) cell in 3 days, but no AFP. In addition Mz-Sto-1 cells and 2 already established gastric cancer cell lines MKN-28 and MKN-45 express HLA- and blood group related antigens (A, Lewis). HLA-DR antigens, which are regularly detected on normal stomach epithelium, are not found on any of the 3 cultured gastric cell lines. Mz-Sto-1 cells represent the first human gastric cancer cell characterized ultrastructurally as signet ring cells. This line will be a valuable tool to study the biology and genetics of gastric carcinoma, to test cytostatic drugs and to define new antigenic markers for stomach cancer.
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PMID:Signet ring stomach cancer: morphological characterization and antigenic profile of a newly established cell line (Mz-Sto-1). 282 Jul 43

Fourteen human primary stomach cancer tissues were screened by Southern blot hybridization using six oncogene probes (myc, myb, H-ras, K-ras, abl, mos), and an amplification of c-myc oncogene was found in one tissue. This is the first report of c-onc amplification in primary stomach cancer tissue.
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PMID:c-myc Gene amplification in primary stomach cancer. 299 14


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