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

The present study establishes the in vitro system for studying the oncosuppression activity of parvovirus and discovers that parvovirus H-1 can be grown cytolytically in various human cancer cell lines, which include 4 hepatoma cell lines (QGY-7703, SMMC-7721, Bel-7402, PLC/PRF/5), 3 gastric cancer cell lines (SGC-7901, MGC-80-3, MKN-28) and 1 naspharynx cancer cell line (CNE). The growth of two primary gastric cancer cell cultures from surgical cancer tissue were also inhibited by the infection of H-1. The sensitivity of cancer cells to H-1 may relate to their differentiation states. On the contrary, H-1 can neither be grown cytolytically in normal liver or stomach cells, nor inhibit their growth. Transformation of human skin fibroblasts with Simian Virus 40 activated their sensitivity to H-1. Our results thus indicate that the antineoplastic activity of H-1 in vivo involves at least its direct inhibiting or killing malignant cells.
 ...
PMID:Inhibitory effect of parvovirus H-1 on cultured human tumour cells or transformed cells. 283 2

Cytotoxic effects of allyl trisulfide (Alt, a synthetic chemical identical with one of the main active principles of garlic), 5 FU, MMC and DDP on SGC 7901 ( a moderately differentiated human gastric adenocarcinoma cell line) and MGC 803 (a poorly differentiated human gastric mucoadenocarcinoma cell line) had been reported before. In this paper, effects of repeated two doses of each drug and the combination of two drugs on these two cell lines were studied using relative clone-survival test. The inhibitory effects of Alt, MMC alone or combined on MGC tumor in nude mice were observed. No drug resistance was found when any one of the four agents at the same concentration were repeated twice separately at 60 hour interval in vitro. The cytotoxic effect of the repeated two doses was approximately equal to that of the single dose at double concentration. The in vitro test of combinations of two drugs showed that Alt plus MMC or 5 FU plus DDP had markedly synergistic effect on MGC cells; 5 FU plus DDP had markedly synergistic effect on SGC cells. The inhibition test on the growth of MGC tumor in nude mice indicated that the inhibition rates of Alt, MMC alone or combined were 58.3%, 86.3% and 84.3%. The systemic toxic effect of MMC alone was severe, whereas Alt alone or MMC plus Alt showed mild toxicity. For this reason, Alt plus MMC is recommended for clinical trials on poorly differentiated gastric cancer. In addition, for the comparison of in vitro test dose and clinical dose of each drug, the principle of clinical adult dose range (CADR) is proposed.
 ...
PMID:[Experimental chemotherapy of human gastric cancer cell lines in vitro and in nude mice]. 284 30

Different characteristic damages of the SGC-7901 gastric adenocarcinoma cells were studied by electron microscopy 1, 36, 72, 96 and 120 hours after heating and radiation in vitro. The visible damages, such as the enlarged mitochondria, increase of lysosomes and perichromatin granules could be shown 1 hour after heating (43 degrees C for 30 min) but no visible damages of the cells were shown until 36 hours following radiation (500 rad). In order to study the ultrastructural changes of the gastric cancer cells in mitosis after heating and radiation, we have used the new method of ultrastructural research in selecting and observing the M cell in vitro and found loosened structure of chromosome and disappearance of microtubules 1 hour following hyperthermia. At the same time, no apparent abnormalities of the mitotic cells were observed after radiation. It is the chief cause of division delay in heat injured cells. However, the chromosomes and microtubules of the new mitotic cells could recover 36 hours after heating (43 degrees C for 30 min). After radiation, the giant cells and abnormal morphologic changes of cells gradually increase and the living cells decrease. Unexpectedly, the division of a few giant cells is observed 72 hours after heating and radiation.
 ...
PMID:[Biologic effects of hyperthermia and radiation on gastric cancer cells (SGC-7901) in vitro. II. Ultrastructural changes of cells]. 344 57

Expression of tumor-associated antigen in different gastric cancer cell lines and different phases of cell cycle was studied cytochemically. The antigen was recognized by the monoclonal antibody (McAb) PC1 against gastric cancer cells. By using the McAb PC1 as first antibody, the indirect immunofluorescence stain and the peroxidase-anti-peroxidase (PAP) stain were done on the gastric cancer cell lines (MGC 803, SGC 7901 and BGC 823). It was shown that PC1 antigen was mainly expressed on the membrane of these cells and only a certain percentage of the cells gave the positive reaction with different intensities. It was obvious that the expression of PC1 antigen was heterogeneous in nature. The heterogeneity of the PC1 antigen expression in gastric cancer cells might be due to either various subpopulations in the cell lines or different phases of cell cycle. In order to go further into the question, we studied quantitatively the expression of PC1 antigen in gastric cancer cell lines (MGC 803, STC 7901 and BGC 823) and the relationship between the antigen expression and cell cycle by double fluorescence stain and two-dimensional flow cytometry. It was found that expression levels of PC1 antigen in these cell lines were in the following order: MGC 803 greater than SGC 7901 greater than BGC 823. The PC1 antigen predominantly expressed on G1 phase for MGC 803 and G1, G2-M phase for SGC 7901 respectively. And uniform low level of PC1 antigen expression was found for BGC 823 throughout the cell cycle. Therefore, the PC1 antigen expression is dependent on cell cycle in MGC 803 and SGC 7901 cell lines.
 ...
PMID:[Expression of the surface antigen in human gastric cancer cells and the relation to cell cycles--correlated analysis with flow cytometry]. 344 58

In vitro antitumor activity of monoclonal antibody MI2 that was made by our laboratory to direct against immunosuppressive acidic protein (IAP) was observed with MTT assay for cytotoxicity. The results showed that the growth of human gastric cancer cell line SGC 7901 was inhibited significantly (P < 0.01) when MI2 was added at a concentration of 7.81 mg/L or higher. The inhibition activity of MI2 appeared to be dose dependent. Increased cytotoxicity (up to 206.3%) of LAK cells against SGC7901 could be remarkably (P < 0.01) induced by addition of MI2 at a concentration of 1.95 mg/L, so the ratio of effector to target was 10:1. The enhancing effect of MI2 on LAK cell activity was also dose dependent. The antitumor activity of MI2 was not associated with human complements.
 ...
PMID:[Antitumor activity of monoclonal antibody MI2 against immunosuppressive acidic protein in vitro]. 788 42

An anti-gastric cancer monoclonal antibody MGb2-mitomycin C conjugate via dextran T-70 as intermediate (MGb2-PAD-MMC) was produced, and 28-30 g molecules of MMC were introduced into 1 g molecule of MGb2. Ninety-six hours after ip of 125I-MGb2-PAD-MMC (1.48 MBq/22 micrograms MGb2 per mouse) to nude mice bearing human gastric cancer SGC-7901, the tumor tissue:blood (T/NT) radioactivity ratio was 2.6, very much higher than that of the control 125I-normal IgG-PAD-MMC group (T/NT = 0.20). Single photo computed tomography imaging confirmed the results of biodistribution study. MGb2-PAD-MMC exhibited selective killing action on the SGC-7901 cells in vitro, which was considered to be mediated by monoclonal antibody MGb2. Nude mice inoculated with SGC-7901 xenograft in bilateral subrenal capsule were treated by MMC (ip), human recombinant interferon-alpha (Hu-IFN-alpha im), MGb2-PAD-MMC (ip) and MGb2-PAD-MMC+Hu-IFN-alpha daily for 5 d beginning 4 h after inoculation. The efficacy of the reagents estimated by the reduction of tumor size and calculated by T/C (%), was 28.3%, 16.4%, 47.8%, and 83.1%, respectively. These results demonstrated that the antitumor effect of MGb2-PAD-MMC was superior to free MMC, and that the Hu-IFN-alpha might further enhance the action of MGb2-PAD-MMC.
 ...
PMID:[Effect of targeting treatment of mitomycin C immunoconjugate on stomach neoplasm]. 801 62

Nine kinds of antineoplastic agents and 2 boron-10 compounds were encapsulated respectively into the immunoliposomes targeted with monoclonal antibody, MGb2, against human gastric cancer. The immunoliposomes were characterized in vitro and in vivo with different nude mouse xenograft models and different routes of administration. The immunore activity was well preserved. The diameter was 100nm for reverse-phase evaporation vesicles and 35nm for small unilamellar vesicles. 1,000-10,000 molecules of antitumor agent were entrapped and 30-80 molecules of MGb2 incorporated per one liposome. They showed selective cytotoxicity to human gastric cancer cell SGC-7901 but very low toxicity to human normal embryonic lung cell SL7. Biodistribution studies indicated that both were better than non-specific liposomes and free drugs. Boronated immunoliposomes could carry boron-10 specifically to SGC-7901 and showed targeted boron neutron capture therapy effects after thermal neutron irradiation. The results confirmed the specific antitumor effects of immunoliposomes in vitro and in vivo and demonstrated the potentiality of the immunoliposomes in the targeting therapy of human gastric cancer.
 ...
PMID:[In vitro and in vivo targeting therapy of immunoliposomes against human gastric cancer]. 806 26

We evaluated the possibility of inducing a productive transfer of the IL-2 gene into human gastic cancer cells (GCC) and assessed the phenotypic and proliferative changes generated in the nude mice. The plasmid vector (BMGNeo-IL-2) carrying the human IL-2 gene was used to transduce the SGC-7901 GCC line by the lipofectin reagent. The IL-2 gene was analyzed by Southern blot and productive IL-2 release using IL-2-dependent CTLL. Cytotoxicity of LAK cells was tested by MTT colorimetry. The kinetics of in vitro growth and proliferation of parental and engineered cells were also measured. Parental and IL-2 gene transduced GCC were injected into nude mice. The tumorigenic potential of IL-2 gene-transfected GCC was evaluated by examining their in vivo growth in nude mice. The productive insertion of the IL-2 gene was achieved in SGC-7901. The amounts of IL-2 constitutively released by the engineered neoplastic cells ranged from 20 to 131 U/ml of IL-2 produced from 10(6) cells in 24 hours. Transduction of GCC with IL-2 gene did not modify the morphology and growth rate. IL-2 gene transfected cells demonstrated increased susceptibility to cell killing by LAK cells. IL-2 producing cells lost their tumorigenicity as evidenced by failure to grow in nude mice. The results demonstrate that IL-2 gene can be productively transduced into human gastric cancer cells without modifying their morphology and growth rate and this transduction leads to reduced or abrogated in vivo tumorigenic potential.
 ...
PMID:[Transduction of the IL-2 gene into human gastric cancer cell: an experimental study]. 1037 81

Gal alpha(1, 3) Gal (gal epitope) is a carbohydrate epitope and synthesized in large amount by alpha(1, 3) galactosyltransferase [alpha(1, 3) GT] enzyme on the cells of lower mammalian animals such as pigs and mice. Human has no gal epitope due to the inactivation of alpha(1, 3) GT gene but produces a large amount of antibodies (anti-Gal) which recognize Gal alpha(1, 3) Gal structures specifically. In this study, a replication-deficient recombinant adenoviral vector Ad5sGT containing pig alpha(1, 3) GT cDNA was constructed and characterized. Adenoviral vector-mediated transfer of pig alpha(1, 3) GT gene into human tumor cells such as malignant melanoma A375, stomach cancer SGC-7901, and lung cancer SPC-A-1 was reported for the first time. Results showed that Gal epitope did not increase the sensitivity of human tumor cells to human complement-mediated lysis, although human complement activation and the binding of human IgG and IgM natural antibodies to human tumor cells were enhanced significantly after Ad5sGT transduction. Appearance of gal epitope on the human tumor cells changed the expression of cell surface carbohydrates reacting with Ulex europaeus I (UEA I) lectins, Vicia villosa agglutinin (VVA), Arachis hypogaea agglutinin (PNA), and Glycine max agglutinin (SBA) to different degrees. In addition, no effect of gal epitope on the growth in vitro of human tumor cells was observed in MTT assay.
 ...
PMID:Adenovirus-mediated expression of pig alpha(1, 3) galactosyltransferase reconstructs Gal alpha(1, 3) gal epitope on the surface of human tumor cells. 1145 43

A series of epipodophyllotoxin carboxylates were prepared from podophyllotoxin by reacting with organic acids under the catalysis of BF3.Et2O. All these products were characterized through IR, 1HNMR, MS and elemental analysis. These compounds showed significant antitumor activities against mouse leukemia P388 and human stomach cancer SGC-7901 in pharmacological tests in vitro.
 ...
PMID:[Synthesis of epipodophyllotoxin carboxylates and antitumor activity in vitro]. 1159 85


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>