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)

In recent years, there has been an increased interest in saliva as a diagnostic tool. Diagnosis of many diseases, including gastric cancer and immunodeficiency, has been made using saliva. The purpose of this study was to determine whether Her2/neu antibody, made in response to certain carcinomas of the breast, could be detected in saliva when experimentally placed at a remote site. This study was conducted using two male SD rats, each weighing between 300 g and 500 g. One experimental animal received 200 microliters, and the other, 500 microliters, of encapsulated c-erbB-2 monoclonal antibody (Signet, Dedham, MA) intraperitoneally. Prior to capsule placement, baseline serum and saliva samples were taken. Samples were also taken twenty, sixty-eight, 140, 188, 308 and 356 hours post-placement. Saliva flow was induced by administration of ophthalmic pilocarpine prior to sampling. All samples were kept at -20 degrees C. Antibody detection was performed using a modified double capture ELISA system. Tissue samples from various organs were evaluated using standard laboratory staining and immunostaining techniques. The animal receiving the higher antibody concentration showed a markedly greater salivary level of the antibody than the other (peak 24.158 hnu/ml vs. 18.313 hnu/ml at 308 and 188 hours post-implantation, respectively). These results seem to indicate that Her2/neu antibody saliva levels may serve as a useful, non-invasive method in the early detection of some breast cancers.
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PMID:Sustained delivery of Her-2/neu antibody by TCPL delivery device using adult male rats as a model. 1272 14

The epidermal growth factor (EGF) receptor and its various ligands (EGF, TGF-alpha, amphiregulin, heparin-binding (HB)-EGF, heregulin, betacellulin) seem to be involved in the growth regulation of intestinal mucosa and might be related to the development and progression of gastrointestinal tumors. However, few quantitative data investigating the impact of tumor-EGF receptor levels in gastrointestinal carcinomas on tumor stage and prognosis are available. Therefore, EGF receptors were quantitatively determined in colorectal carcinomas in comparison to adjacent normal mucosa by 125I[EGF]-binding studies. EGFR capacity was increased in advanced invasive colorectal carcinomas (T1/2 vs. T3/4 tumors, p<0.001) and advanced UICC stages (UICC I vs. UICC II/III, p<0.001). These findings were confirmed with quantitative 125[I]EGF autoradiography performed on frozen tissue slides and analyzed by laser densitometry (p=0.020). EGF receptor analysis with immunohistochemistry with EGFR antibodies directed against the extracellular domain of the receptor was not correlated with tumor invasion or prognosis. mRNA-expression of EGFR ligands was investigated using semiquantitative RT-PCR amplification using specific primers. RT-PCR transcripts of EGFR ligands (EGF, TGF-alpha, HB-EGF, and amphiregulin) were detected in both carcinomas and normal mucosa, indicating that autocrine growth stimulation of colorectal carcinomas is mediated by coexpression of EGF receptor ligands and upregulation of EGF receptors. Survival of colorectal cancer patients with increased tumor EGF receptor levels was significantly reduced in comparison to patients with low/unchanged tumor EGF receptor levels (mean survival+/-SD, 36.2+/-4.0 vs. 46.8+/-4.3 months; p=0.017). Further studies investigating EGF receptor levels in gastric cancer patients have shown that increased tumor EGF receptor levels were associated with poor prognosis in gastric cancer patients with tumors localized distal from the cardia. Several specific EGF receptor tyrosine kinase inhibitors have recently entered clinical phase I-III studies, with promising antitumor effects in several tumors, including gastrointestinal cancer. Therefore, patients with invasive gastric or colorectal carcinomas might benefit from therapies specifically blocking EGFR-mediated signal transduction.
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PMID:Clinical implications of the EGF receptor/ligand system for tumor progression and survival in gastrointestinal carcinomas: evidence for new therapeutic options. 1279 Mar 26

Alterations of the HER-2 (erbB-2/neu) proto-oncogene have been associated with carcinogenesis and poor prognosis of certain cancers. A single nucleotide polymorphism (Ile/Val, A/G) in the transmembrane domain was reported to be associated with a risk of breast cancer. In our study, we examined the association between the HER-2 polymorphism and gastric carcinoma. The Ile/Ile, Ile/Val and Val/Val genotypes were found in 146 (68.9%), 56 (26.4%) and 10 (4.7%) of 212 gastric cancer patients and in 234 (81.5%), 48 (16.7%) and 5 (1.8%) of 287 control subjects, respectively. The Ile/Val or Val/Val genotype was significantly more frequent in patients than in controls (p = 0.005 and 0.033, respectively). The OR of Val/Val genotype then revealed a significantly enhanced risk of 3.25 (95% CI 1.09-9.70) compared to Ile/Ile genotype; heterozygous Ile/Val genotype showed an intermediate risk of 1.97 (1.27-3.06). In patients, carcinomas of advanced stage were significantly more frequent in patients with Ile/Val or Val/Val genotype than those with Ile/Ile genotype (p < 0.001). The logistic regression analysis for tumor invasion, lymph node metastasis and distant metastasis revealed that lymph node metastasis was most closely associated with the HER-2 genotype. These results suggest that this nucleotide polymorphism in the transmembrane domain-coding region of HER-2 could be associated with development of gastric carcinoma and may serve as a predictor of risk for a malignant phenotype of gastric cancer. The association of HER-2 genotype with clinicopathologic characteristics of gastric cancer was also suggested, which has to be confirmed with a larger sample size.
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PMID:A single nucleotide polymorphism in the transmembrane domain coding region of HER-2 is associated with development and malignant phenotype of gastric cancer. 1452 Jun 97

The various treatments for advanced gastric cancer have limitations and induce only marginal survival benefit. HER-2/neu protein is overexpressed in several types of human cancers and its amplification is associated with poor prognosis. Recombinant humanized anti-HER-2/neu antibody (trastuzumab) not only inhibits the proliferation of HER-2/neu overexpressing tumor cells but also augments the cytotoxicity of concomitant chemotherapeutic agents in metastatic breast cancer. In this study, we evaluated the growth inhibitory effects of trastuzumab in gastric cancer cells. HER-2/neu protein was evaluated by immunohistochemical analysis in seven gastric cancer cell lines. MTT assay was performed to evaluate the growth inhibitory effects of trastuzumab and three chemotherapeutic agents, doxorubicin, cisplatin and paclitaxel, both alone and in combinations. The changes of cell cycle after trastuzumab treatment were analyzed by flow cytometry. Four of the cell lines, YCC-2 with strong positivity of HER-2/neu expression, NCI-N87 with moderate positivity, YCC-3 with weak positivity, and SK-BR-3 as a positive control, were selected. After in vitro MTT assay for 1-day and 5 consecutive days' treatment of trastuzumab at various concentrations, growth inhibition was not observed in any cancer cell lines. However, there was variable dose-dependent sensitivity to doxorubicin, cisplatin and paclitaxel. YCC-2 and SK-BR-3 cancer cells were more sensitive to three chemotherapeutic drugs, constantly (P<0.05). The combination of 5 consecutive days' treatment of trastuzumab with 1-day doxorubicin treatment showed significant growth inhibition only in YCC-2 and NCI-N87 gastric cancer cells. After 1-day trastuzumab treatment, the S-phase fraction was decreased by 52 and 70% in YCC-2 and SK-BR-3, respectively. In conclusion, the expressions of HER-2/neu protein in gastric cancer cells are variable, and concomitant treatments of trastuzumab with doxorubicin increase cytotoxicity. This suggests that trastuzumab-based biologic therapy with chemotherapeutic agents can be applied in gastric cancer treatment.
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PMID:Growth inhibitory effects of trastuzumab and chemotherapeutic drugs in gastric cancer cell lines. 1536 48

The ligand-less receptor HER2/neu (erbB-2) has been proposed as a prognostic marker of gastric cancer that correlates with poor clinical outcome, indicating that HER2 signals play an important role in gastric cancer progression. This study demonstrated that two major natural lysophospholipids, lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P), induce rapid and transient phosphorylation of HER2 in two human gastric cancer cell lines, MKN28 and MKN74 cells. We also revealed that tyrosine phosphorylation of HER2 induced by both lysophospholipids was significantly attenuated by two inhibitors, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, AG1478, and a broad-spectrum matrix metalloproteinase inhibitor, GM6001. This suggests that the pathway of HER2 transactivation induced by these lysophospholipids is dependent on the proteolytically released EGFR ligands. Our results indicate that LPA and S1P act upstream of HER2 in gastric cancer cells, and thus may act as potent stimulators of gastric cancer.
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PMID:Lysophospholipids transactivate HER2/neu (erbB-2) in human gastric cancer cells. 1564 31

The c-erbB-2 protein is overexpressed in 7% of gastric cancer cases, suggesting that anti-c-erbB-2 antibody therapy (trastuzumab; Herceptin) could be used. We report here a 28-year-old woman with metastatic gastric cancer overexpressing c-erbB-2 (3 + strong membrane staining on immunohistochemistry) who was treated with trastuzumab in combination with chemotherapy. A complete response was obtained with a combination of trastuzumab and oxaliplatin and was maintained with trastuzumab alone for 18 months. The patient relapsed and chemotherapy (capecitabine, docetaxel) was combined with the anti-c-erbB-2 antibody. The patient survived for 4 years with metastatic disease controlled for 2 years by immunochemotherapy. We conclude that the combination of trastuzumab and chemotherapy is efficient in the treatment of metastatic gastric carcinoma with overexpression of the c-erbB-2 protein.
Gastric Cancer 2005
PMID:The effectiveness of trastuzumab (Herceptin) combined with chemotherapy for gastric carcinoma with overexpression of the c-erbB-2 protein. 1632 93

Approximately 23,000 new gastric cancer cases and 12,000 associated deaths occur annually in the United States. Intestinal metaplasia and gastric epithelial dysplasia are precursor lesions to gastric adenocarcinoma, but are not readily detectable clinically, radiographically, or endoscopically. A noninvasive method of precursor detection would require the ability to distinguish precursor lesions from adjacent normal mucosa. In search of such markers, tissue microarrays were prepared for 133 patients of resected gastric adenocarcinoma. Tissue microarrays contained primary cancer, normal stomach, intestinal metaplasia, and gastric epithelial dysplasia and were probed with antibodies against nine potential markers that were either identified in a database of genes overexpressed in gastric adenocarcinoma or were already of interest to our laboratory: claudin-4, mitogen-activated protein kinase kinase 4 (MKK4), 14-3-3sigma (stratifin), S100A4, mesothelin, fascin, topoisomerase IIalpha, HER-2/neu, and epithelial growth factor receptor. Three markers discriminated gastric adenocarcinoma precursor lesions from normal gastric mucosa. Claudin-4 expression was present in 36 intestinal metaplasia lesions (100%) and 14 gastric epithelial dysplasia lesions (100%), but in only 16 normal stomach samples (15%). MKK4 expression was present in 24 intestinal metaplasia lesions (89%) and 12 gastric epithelial dysplasia lesions (100%), but in only 6 normal stomach samples (8%). Stratifin expression was present in 29 intestinal metaplasia lesions (97%) and 8 gastric epithelial dysplasia lesions (100%), but in only 2 normal stomach samples (3%). Sensitivity and specificity for detection of the precursor lesion intestinal metaplasia were 100% and 85%, respectively, for claudin-4; 89% and 92%, respectively, for MKK4; and 97% and 97%, respectively, for stratifin. In primary cancers, 123 of 125 (98.4%) were positive for claudin-4, 116 of 126 (94%) for MKK4, and 111 of 120 (92%) for stratifin. In conclusion, claudin-4, MKK4, and stratifin immunolabeling detects precursor lesions of gastric adenocarcinoma that are otherwise clinically, radiographically, and endoscopically inapparent. These findings may prove useful in the diagnosis and therapeutic targeting of gastric adenocarcinoma precursor lesions.
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PMID:Claudin-4, mitogen-activated protein kinase kinase 4, and stratifin are markers of gastric adenocarcinoma precursor lesions. 1649 16

Olive oil is an integral ingredient of the "Mediterranean diet" and accumulating evidence suggests that it may have a potential role in lowering the risk of several types of cancers. The mechanisms by which the cancer-preventing effects of olive oil can be performed, however, are not known. We recently hypothesized that a novel molecular explanation concerning the anti-cancer actions of olive oil may relate to the ability of its monounsaturated fatty acid (MUFA) oleic acid (OA; 18:1n-9) to specifically regulate cancer-related oncogenes. Supporting our hypothesis, exogenous supplementation of cultured breast cancer cells with physiological concentrations of OA was found to suppress the overexpression of HER2 (Her-2/neu, erbB-2), a well-characterized oncogene playing a key role in the etiology, progression and response to chemotherapy and endocrine therapy in approximately 20% of breast carcinomas. OA treatment was also found to synergistically enhance the efficacy of trastuzumab, a humanized monoclonal antibody binding with high affinity to the ectodomain (ECD) of the Her2-coded p185(HER2) oncoprotein. Moreover, OA exposure significantly diminished the proteolytic cleavage of the ECD of HER2 and, consequently, its activation status, a crucial molecular event that determines both the aggressive behavior and the response to trastuzumab of Her2-overexpressing breast carcinomas. Our most recent findings further reveal that OA exposure may suppresses HER2 at the transcriptional level by up-regulating the expression of the Ets protein PEA3 -a DNA-binding protein that specifically blocks HER2 promoter activity- in breast, ovarian and stomach cancer cell lines. This anti-HER2 property of OA offers a previously unrecognized molecular mechanism by which olive oil may regulate the malignant behavior of cancer cells. From a clinical perspective, it could provide an effective means of influencing the outcome of Her-2/neu-overexpressing human carcinomas with poor prognosis. Indeed, OA-induced transcriptional repression of HER2 oncogene may represent a novel genomic explanation linking "Mediterranean diet", olive oil and cancer as it seems to equally operate in various types of Her-2/neu-related carcinomas.
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PMID:Mediterranean diet, olive oil and cancer. 1663 35

The HER-2/neu protein is intimately involved with normal cell proliferation and tissue growth and is extensively homologous and related to the epidermal growth factor receptor. HER-2/neu protein expression has been most intensively studied in the context of breast carcinoma, in which its amplification and overexpression correlate with the overall course of disease, and with a poor prognosis, and constitute a predictive factor of poor response to chemotherapy and endocrine therapy. In this study, we investigated the relationship between the expression of HER-2/neu and the clinicopathological characteristics of tumors, including survival. This study was performed with a view toward the future introduction of Herceptin therapy for gastric cancer patients. HER-2/neu overexpression and gene amplification was examined with semiquantitative standardized immunohistochemical staining, chromogenic in situ hybridization (CISH), and fluorescence in situ hybridization (FISH) in 182 gastric cancer patients who underwent curative surgery at the Kangbuk Samsung Hospital. Twenty-nine (15.9%) of 182 patients expressed the HER-2/neu protein by immunohistochemistry. HER-2/neu gene amplification was detected in seven patients by CISH and FISH. Intestinal-type cancers exhibited higher rates of HER-2/neu amplification than did diffuse-type cancers (P < 0.05). Tumors with HER-2/neu amplification were associated with poor mean survival rates (922 vs 3243 days) and 5-year survival rates (21.4% vs 63.0%; P < 0.05). Age, TNM stage, and amplification of HER-2/neu were found to be independently related to survival by multivariate analysis. HER-2/neu amplification may constitute an independent prognostic factor in gastric cancer patients, and patients exhibiting HER-2/neu amplification might constitute potential candidates for new adjuvant therapies which involve the use of humanized monoclonal antibodies.
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PMID:HER-2/neu amplification is an independent prognostic factor in gastric cancer. 1686 27

Topoisomerase IIalpha (topoIIalpha) is an enzyme required for DNA replication and a molecular target for drugs called anthracyclines. The topoIIalpha gene (TOP2A) is located close to the HER-2/neu oncogene (HER2). We assessed gastric cancers to (1) clarify the relationship between gene amplification and protein overexpression of topoIIalpha and HER2; (2) evaluate the correlation between gene amplification and protein overexpression of topoIIalpha; and (3) examine the relationship between the results of immunohistochemistry and Western blot analysis for topoIIalpha. In a combined analysis of immunohistochemistry and fluorescence in situ hybridization on 552 formalin-fixed and paraffin-embedded gastric cancer tissues, 38 cases were found to have HER2 amplification. Further examination by fluorescence in situ hybridization revealed amplification of TOP2A in 13 of the 38 cases. No aberrations in the TOP2A gene were observed in cases without HER2 overexpression, except for one containing a gene deletion. The TopoIIalpha protein-labeling index was not correlated with TOP2A amplification. Fluorescence in situ hybridization was performed on nuclear imprint specimens obtained from 9 cases using simultaneous probes for TOP2A, HER2, and centromere 17. Of these 9 cases, 3 displayed coamplification of TOP2A and HER2, and only 1 of the 3 cases revealed a high expression of topoIIalpha in Western blot. Although patients having gastric adenocarcinoma with TOP2A amplification could be considered suitable for clinical trials, information involving anthracycline therapy is not firmly understood in regards to the status of TOP2A amplification or protein overexpression. Therefore, results of the current study will provide further insight for the clinical application of anthracycline in gastric cancers.
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PMID:Topoisomerase IIalpha gene amplification in gastric carcinomas: correlation with the HER2 gene. An immunohistochemical, immunoblotting, and multicolor fluorescence in situ hybridization study. 1694 20


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