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)

Previously, we reported that adenoviral vectors carrying the carcinoembryonic antigen (CEA) promoter sequences to direct the Echerichia coli beta-galactosidase gene (AdCEA-lacZ) or cytosine deaminase (CD) gene (AdCEA-CD) confer selective gene expression on a CEA-positive gastric cancer cell line (MKN45) in vitro. Here, adenovirus-mediated tumor-specific gene therapy for CEA-positive gastric carcinoma in vivo was investigated. Using an animal model with i.p. disseminated MKN45 tumors, adenovirus-mediated tumor-specific transgene expression and therapeutic efficacy were analyzed. After an i.p. injection of AdCEA-lacZ, beta-galactosidase activity was confined to tumor xenografts. Moreover, CD mRNA was expressed exclusively in MKN45 tumor xenografts after infection with AdCEA-CD, despite the fact that an adenovirus-mediated transfer of CD DNA was detected in all tissues tested. In contrast, CD mRNA was detected not only in tumor xenografts but also in other organs of mice infected with AdCA-CD, in which CD gene expression is governed by an ubiquitous promoter. Suppression of tumor growth and prolongation of survival were noted in tumor-bearing mice treated with AdCEA-CD and 5-fluorocytosine (5FC) without observable adverse effects. In contrast, significant hepatic toxicity was noted in animals treated with AdCA-CD. These results reveal that the CEA promoter restricts CD gene expression to CEA-positive tumor cells in the adenoviral context in vivo, along with the beneficial therapeutic effects of 5FC treatment, suggesting the i.p. AdCEA-CD/5FC system may provide a novel approach to treatment of i.p. disseminated gastric cancer.
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PMID:In vivo selective gene expression and therapy mediated by adenoviral vectors for human carcinoembryonic antigen-producing gastric carcinoma. 933 Oct 89

To comparatively evaluate the frequency of the neuroendocrine differentiation in the early and in the advanced stage of the disease, 189 gastric carcinomas (67 early gastric cancers and 122 advanced gastric cancers) were studied by immuno-histochemistry using a monoclonal antibody against chromogranin A (CgA). CgA-positive tumor cells were detected in 55 of 189 gastric carcinomas (29.1%). Twenty-two of 67 early gastric cancer (EGC) (32.8%), and 33 of 122 advanced gastric cancer (AGC) (27.0%) were CgA positive. The latter included 23 intestinal type, 8 diffuse type and 2 mixed type tumors. The distribution of CgA-positive tumor cells in most AGC and EGC was focal and the endocrine cells were singularly scattered in the neoplastic glands or, more rarely, grouped in small clusters. CgA-positive tumor cells, moreover, were observed in the lymph node metastases of 12 AGC and 1 EGC. Statistical analysis of data showed no significant difference in the frequency of CgA-positive endocrine cells with regard to the stage of tumor growth, histotype, sex and age. These results indicate that neuroendocrine differentiation is a phenomenon independent of tumor stage, histotype, age, and sex and that CgA-positive cells are present during the whole neoplastic progression.
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PMID:[Comparative study of endocrine differentiation in early and advanced stomach carcinoma]. 941 59

To create cytotoxic hybrid analogs of somatostatin (SST), octapeptides RC-160 (D-Phe-Cys-Tyr-D-Trp- Lys-Val-Cys-Trp-NH2) and RC-121 (D-Phe-Cys-Tyr-D-Trp- Lys-Val-Cys-Thr-NH2) were linked to doxorubicin (DOX) or its superactive derivative, 2-pyrrolino-DOX (AN-201). The conjugation was performed by coupling N-9-fluorenylmethoxycarbonyl (N-Fmoc)-DOX-14-O-hemiglutarate or 2-pyrrolino-DOX-14-O-hemiglutarate to the amino terminus of [Lys(Fmoc)5]RC-160 yielding AN-163 and AN-258, respectively, after deprotection. The respective cytotoxic conjugates of RC-121 (AN-162 and AN-238) were prepared similarly. In vitro tests on human cancer cell lines-MKN-45 gastric cancer, MDA-MB-231 breast cancer, PC-3 prostate cancer, and MIA PaCa-2 pancreatic cancer-demonstrated that the antiproliferative activity of the cytotoxic radicals in these conjugates was virtually retained. In H-345 human small cell lung carcinoma cell line, conjugates of RC-121 preserved the cytotoxic activity of their radicals, but the hybrids with RC-160 showed approximately 10 times lower activity. The ability of the carriers and the hybrids to inhibit the binding of 125I-labeled RC-160 to receptors for SST on rat pituitary membrane preparation was also determined. The cytotoxic conjugates inhibited 50% of the specific binding of the radioligand in the nanomolar concentration range (IC50 < 80 nM). When SST-like activities of AN-238 and its carrier, RC-121, were compared in the rat pituitary superfusion system, both compounds were found to suppress a stimulated growth hormone release at nanomolar concentrations. Preliminary studies in animal models of breast and prostate cancers showed that AN-238 is less toxic than AN-201 and more potent in inhibiting tumor growth. These highly active cytotoxic analogs of SST have been designed as targeted antitumor agents for the treatment of various cancers expressing receptors for SST octapeptides.
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PMID:Synthesis and biological evaluation of cytotoxic analogs of somatostatin containing doxorubicin or its intensely potent derivative, 2-pyrrolinodoxorubicin. 946 96

This study was conducted to identify tumor types warranting Phase II clinical trials of oxaliplatin using the human tumor cloning assay. Oxaliplatin was tested at concentrations ranging from 0.5 to 50.0 microg/ml in 1-h and 14-day continuous exposures along with 1.4 microg/ml carboplatin and 0.2 microg/ml cisplatin for comparison. We defined in vitro response as tumor growth inhibition >50% of control. In the 1-h exposure schedule, in vitro responses were observed in 9 of 116 (8%), 18 of 115 (16%), 38 of 103 (37%), and 7 of 13 (54%) tumor specimens at concentrations of 0.5, 5.0, 10.0, and 50.0 microg/ml oxaliplatin, respectively. In the 14-day exposure schedule, in vitro responses were observed in 10 of 121 (8%), 37 of 121 (31%), 57 of 106 (54%), and 15 of 15 (100%) tumor specimens at concentrations of 0.5, 5.0, 10.0, and 50.0 microg/ml oxaliplatin, respectively. Activity was observed against colon cancer, non-small cell lung cancer, gastric cancer, and melanoma colony-forming units. In both cisplatin-resistant and cisplatin-sensitive tumors, the activity of oxaliplatin was concentration and time dependent. A 1-h exposure to 5.0 and 10.0 microg/ml oxaliplatin led to 7.4 and 23.4% in vitro responses, respectively, in specimens resistant to 1-h exposure of 0.2 microg/ml cisplatin. Moreover, 1-h exposures to 5.0 microg/ml and 10.0 microg/ml oxaliplatin showed in vitro antitumor responses in 10.2 and 24.3%, 17.2 and 34.5%, 10.0 and 20.0%, 6.7 and 16.7%, and 11.4 and 34.3% of specimens resistant to 1.4 microg/ml carboplatin, 6.0 microg/ml 5-fluorouracil, 3.0 microg/ml irinotecan, 10.0 microg/ml paclitaxel, and 0.04 microg/ml doxorubicin, respectively. The effect in those drug-resistant specimens was improved when oxaliplatin was used on the protracted exposure regimen. Our data indicate that oxaliplatin is an active drug in vitro against a large variety of human tumors. Both concentration and duration of exposure are important factors for oxaliplatin cytotoxicity. The broad spectrum of activity and the in vitro activity against some tumors primarily resistant to conventional anticancer drugs encourage further clinical investigations of oxaliplatin in patients with advanced cancer refractory to conventional chemotherapy.
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PMID:Activity of oxaliplatin against human tumor colony-forming units. 956 98

Our previous experience has demonstrated that growth of gastric cancer during the waiting period for surgery cannot be neglected, and some patients hope to receive prophylactic treatment to inhibit the growth of tumor until surgery. The present study was designed to assess the clinical benefits of preoperative chemotherapy with oral UFT for gastric cancer during the waiting period for surgery. Fifty patients with gastric cancer (24 early, 25 advanced and 1 recurrent cancers) were treated with oral UFT at 300-600 mg/day for 7-36 days before surgery and the objective responses and the postsurgical survivals were evaluated. In 42 of 50 patients objective responses of primary lesions were assessed by endoscopy or upper gastrointestinal series examination, and 2 CRs, 15 PRs and 25 NCs were seen (40% response). The histological effect was evaluated in 50 patients and the following classifications were made: grade 3 (complete disappearance or necrosis of tumor cells), 2; grade 2 (necrotic changes > 2/3 area), 4; grade 1b (> 1/3 area), 7; grade 1a (< 1/3 area), 15; and grade 0 (no histological changes), 22. A longer period of UFT administration was associated with CR or PR. All the patients underwent gastrectomy (38 curative and 12 palliative gastrectomies): all patients with Stage I-III primary gastric cancer are alive after surgery, and the 50% survival period of the patients with Stage IV cancer was 20 months. The side effects were not serious, including slight myelotoxicity, liver dysfunction and anorexia. It is concluded that preoperative chemotherapy for gastric cancer with oral UFT on outpatient basis may result in down-staging as well as the prevention of tumor growth during the waiting period for surgery without serious side effects.
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PMID:Neoadjuvant chemotherapy of gastric cancer with oral UFT (a mixture of uracil and fturafur) during the waiting period for surgery. 956 72

In gene therapy for malignancy, the herpes simplex virus thymidine kinase (HSVtk)-ganciclovir (GCV) system has been widely used. For pancreatic cancer targeting, we estimated the therapeutic efficacy of gene transduction by an adenovirus-carrying HSVtk gene under the control of a carcinoembryonic antigen (CEA) promoter (AdCEAtk) followed by systemic administration of GCV. Four cell lines, CEA-producing Su.86.86. BxPC-3 (pancreatic cancer cells), MKN45 (gastric cancer cells) and CEA-nonproducing HeLa, were used for analysis of GCV sensitivity induced by adenoviral gene transduction. To evaluate the therapeutic efficacy of AdCEAtk and GCV administration in human CEA-positive pancreatic cancer in vivo, a subcutaneously implanted tumor-bearing nude mouse model was used. When the HSVtk gene was transduced with a ubiquitous promoter into these cells, increase of the GCV sensitivity was independent of CEA-production. In contrast, when the cells were transduced with a CEA promoter, the cell-killing effect of GCV was increased in only CEA-producing cells. For in vivo analysis, AdCEAtk was delivered into subcutaneously established tumors of Su.86.86 cells. Immunohistochemical staining of the tumor showed that HSVtk protein was expressed only in tumor cells, and tumor growth was markedly suppressed by administration of GCV. These results suggest that the adenovirus-mediated transfer of HSVtk gene with CEA promoter specifically increases the GCV sensitivity of CEA-producing pancreatic cancer cells in vitro and in vivo. This strategy may provide a useful tool for treating pancreatic cancer, especially CEA-producing tumor cells.
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PMID:In vivo adenovirus-mediated prodrug gene therapy for carcinoembryonic antigen-producing pancreatic cancer. 961 53

Fuzheng Huoxue Anticancer prescription (FZHXAC) showed better clinical effect in treating 35 cases of postoperative patients with gastric cancer in middle or late stage as compared with 35 cases of controls. After treatment, the immune function of T-lymphocytes enhanced significantly, the hypercoagulability improved, the criteria such as OKT4/OKT8 ratio, antithrombase III (AT-III), fibrinolytic activity, etc were all normalized, the one year, 3 year and 5 year suvival rate of patient were elevated. FZHXAC showed obvious inhibitory action on tumor growth in nude mice with transplanted human gastric cancer, as compared with control, the difference was significant, P < 0.001. In comparing with chemotherapeutic drug 5-fluorouracil, FZHXAC showed no significant toxicity, it didn't influence the normal growth of body weight. These results suggested that FZHXAC could not only replenish the Zheng-Qi, improve blood circulation, improve immune function and extend the survival period of patient, but also might have direct inhibiting, killing action on gastric tumor cells, this problem is expecting for further research.
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PMID:[Clinical and experimental studies on treatment postoperative gastric cancer with combined therapy of fuzhen huoxue anticancer prescription and chemotherapy]. 977 96

Angiogenesis is essential for tumor growth and metastasis and depends on the production of angiogenic factors by host and/or tumor cells. The role of angiogenesis and angiogenic factor expression in intestinal- and diffuse-type gastric cancer are undefined. Archival specimens of 51 intestinal-type and 38 diffuse-type human gastric carcinomas were examined for tumor vessel counts, angiogenic factor expression, and the presence or absence of angiogenic factor receptors on tumor endothelium using antibodies against vascular endothelial growth factor (VEGF) and its receptors (KDR and flt-1), basic fibroblast growth factor (bFGF) and its receptors (bek and flg), and factor VIII (endothelial cells). Vessel count and VEGF and bFGF expression were higher in intestinal-type than in diffuse-type gastric cancers (P = 0.01, P < 0.001, and P < 0.001, respectively). Similarly, vessel count and VEGF expression were higher in patients with liver metastasis than in patients with peritoneal dissemination (P = 0.003 and P = 0.01, respectively). Vessel count correlated with VEGF expression and the presence of endothelial KDR in intestinal-type gastric cancer (P = 0.003 and P = 0.02, respectively) but not diffuse-type gastric cancer. Vessel count, VEGF expression, and presence of endothelial KDR increased with increasing stage of disease in intestinal-type gastric cancer but not diffuse-type gastric cancer. The expression of bFGF and its receptors did not correlate with vessel count in either cancer type. These findings suggest that the pattern of metastasis in intestinal-type gastric cancer is angiogenesis dependent. The correlation of VEGF expression and its endothelial receptor with vessel count and stage of disease suggests that VEGF is at least one of the factors responsible for the induction of angiogenesis in intestinal-type gastric cancer.
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PMID:Significance of vessel count and vascular endothelial growth factor and its receptor (KDR) in intestinal-type gastric cancer. 981 16

Vascular endothelial growth factor (VEGF), a very important in the process of tumor angiogenesis, was chosen as a target in a study to determine whether manipulation of angiogenesis with antibody against VEGF may interrupt tumor growth and metastasis. Anti-VEGF antibody was obtained from immunized rabbits, purified on an affinity column, and identified as neutralized antibody by Mile's assay. IVTA2MA891, a murine spontaneous breast cancer with a high rate of metastasis in lung in TA2 x 615 F1 mice, was chosen as an animal model in this study, because of the high expression of VEGF in the primary tumor as well as in the lung metastatic tumor. The anti-VEGF antibody could inhibit growth of S180 sarcoma in a dose-dependent manner, and the inhibition rate could reach 41.0% with a dose of 200 microg mouse(-1) day(-1). Anti-VEGF antibody could inhibit tumor growth by 76.2% in nude mice bearing human gastric cancer (MGC 803). When anti-VEGF antibody was combined with 131I-3H11, a murine monoclonal antibody conjugated with 131I, only one of five nude mice developed tumor and 84.0% more inhibition of tumor growth was obtained in comparison with treatment by 131I-3H11 alone. The growth of the primary tumor was inhibited by 44.0% and the number and size of the metastatic foci in the lungs were reduced by 73.0% and 83.7% respectively in the animal model, with a high rate of metastasis in lung. The anti-VEGF antibody may be potentially useful for clinical treatment of cancer and metastasis.
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PMID:The effect of antibody against vascular endothelial growth factor on tumor growth and metastasis. 986 Feb 90

In various types of human malignant tumors, the presence or absence of expression of apoptosis-associated gene products (p53 protein and Bcl-2 protein) and the tumor proliferation activity-related factor (Ki-67) was assessed by immunohistochemical staining and the correlation between this expression and chemosensitivity to anticancer drugs was investigated. Study subjects comprised 55 preoperative patients with untreated malignant tumors (9 with esophageal cancer, 11 with stomach cancer, 11 with colon cancer, 13 with hepatic cancer and 11 with breast cancer). A chemosensitivity test was carried out with the histoculture drug response assay (HDRA) method using 4 drugs, mitomycin C (MMC), 5-fluorouracil (5-FU), doxorubicin hydrochloride (ADM), and cisplatin (CDDP). Immunohistochemical staining was used to assess expression of p53 protein, Bcl-2 protein and Ki-67. The tumor growth inhibition index (I.I.) of the 4 drugs was significantly lower in a group of the patients with p53 protein overexpression-type (mutant p53 protein positive expression-type) tumors than in a group with p53 protein negative expression-type tumors (p<0.05). No significant correlation was found between the expression of the Bcl-2 protein by and the I.I. of any drug studied in any type of cancer. A negative correlation was found between the labeling index (L.I.) for Ki-67 in all cases and I.I. for MMC and ADM and thus, chemosensitivity of the tumors with high growth activity was lower. Furthermore, a positive correlation existed between the L.I. for Ki-67 and that for p53 protein. The patients with p53 protein overexpression-type (mutant p53 protein positive) tumors showed low chemosensitivity. In addition, overexpression of p53 protein is suggested to be one of the factors involved in the lowered chemosensitivity of the tumors with high growth activity. Summarizing these findings, the p53 protein can play an important role in cancer therapy.
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PMID:Usefulness of p53 protein, Bcl-2 protein and Ki-67 as predictors of chemosensitivity of malignant tumors. 1020 14


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