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)

Helicobacter pylori is a gram-negative bacterium affecting about half of the world population, causing chronic gastritis type B dominated by activated phagocytes. In some patients the disease evolves into gastric ulcer, duodenal ulcer, gastric cancer or MALT lymphoma. The pathogenesis is in part caused by the immunological response. In mouse models and in human disease, the mucosal immune response is characterized by activated phagocytes. Mucosal T-lymphocytes are producing IFN-gamma thus increasing mucosal inflammation and mucosal damage. A low dietary intake of antioxidants such as carotenoids and vitamin C may be an important factor for acquisition of H. pylori by humans. Dietary antioxidants may also affect both acquisition of the infection and the bacterial load of H. pylori infected mice. Antioxidants, including carotenoids, have anti-inflammatory effects. The aim of the present study was to investigate whether dietary antoxidant induced modulation of H. pylori in mice affected the cytokines produced by H. pylori specific T-cells. We found that treatment of H. pylori infected mice with an algal cell extract containing the antioxidant astaxanthin reduces bacterial load and gastric inflammation. These changes are associated with a shift of the T-lymphocyte response from a predominant Th1-response dominated by IFN-gamma to a Th1/Th2-response with IFN-gamma and IL-4. To our knowledge, a switch from a Th1-response to a mixed Th1/Th2-response during an ongoing infection has not been reported previously.
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PMID:Treatment of H. pylori infected mice with antioxidant astaxanthin reduces gastric inflammation, bacterial load and modulates cytokine release by splenocytes. 1065 72

Modulation of interferon-gamma effect by other drug may enhance its tumor specific activity. The apoptosis inducing effect of interferon-gamma and its modulation by cyclosporin-A or tacrolimus (FK-506) were investigated in in vitro and ex vivo experiments. We found that a combination of cyclosporin-A (CsA) and recombinant interferon-gamma (rIFN-gamma) induced significant apoptosis in all four types of human gastric carcinoma cells tested but not in normal cells such as human peripheral blood mononuclear cells (PBMCs), human omentum-derived mesothelial cells, or human umbilical vein endothelial cells (HUVECs) in vitro. Apoptosis was also induced by a combination of rIFN-gamma with FK-506 but not with rapamycin. Next, the apoptosis-inducing effect of endogenous IFN-gamma combined with cyclosporin-A was examined using clinical samples. A streptococcal preparation, OK-432, was administered intraperitoneally for the management of 12 gastric cancer patients with malignant ascites. None of the gascitic fluids obtained before the OK-432 injection showed detectable IFN-gamma level. The OK-432 injection induced a detectable IFN-gamma production ranging from 6 to 89 pg/mL in ascitic fluids from 9 out of the 12 patients. A combination of CsA with ascitic fluids collected after but not before OK-432 injection induced significant apoptosis in MK-1 cells, a gastric carcinoma cell line. A positive correlation was found between the IFN-gamma level and CsA-induced apoptosis. The CsA-induced apoptosis was also blocked by a specific antibody against human IFN-gamma. These results indicated that both recombinant and endogenous IFN-gamma can induce potent tumor-apoptosis when combined with CsA.
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PMID:A combination of cyclosporin-A (CsA) and interferon-gamma (INF-gamma) induces apoptosis in human gastric carcinoma cells. 1113 36

To evaluate the mechanisms of T-cell dysfunction in patients with gastric cancer, we investigated the caspase activity of T cells, the induction of spontaneous T-cell apoptosis, the expression of T-cell receptor (TCR) zeta molecules, and the ability of T cells to produce cytokines in peripheral blood lymphocytes from patients (n = 22) and healthy controls (n = 14). The caspase-3 activity of T cells was studied as the protease activity of caspase-3 using the cell-permeable substrate of PhiPhiLux G1D2. Flow cytometric analysis was performed with triple staining by annexin V-FITC, propidium iodide, and CD3-R-phycoerythrin-Cy5 for the detection of T-cell apoptosis and with intracellular staining using permeabilized cells for the expression of TCR-zeta molecules. IFN-gamma and tumor necrosis factor alpha production from T cells was evaluated in response to anti-CD3 stimulation. Caspase-3 activity of peripheral blood T cells from patients with advanced disease was significantly increased compared with that from controls [15.5 +/- 3.6 mean fluorescence intensity (MFI) versus 11.5 +/- 3.3 MFI; P = 0.0068]. Parallel to this, the apoptosis of peripheral blood T cells from patients with advanced disease was significantly higher than for those from controls (16.5 +/- 15.5% versus 4.8 +/- 2.7%; P = 0.010). Furthermore, the expression of TCR-zeta molecules in patients with advanced disease was significantly decreased in comparison with that of the controls (41.0 +/- 13.9 MFI versus 56.7 +/- 16.3 MFI; P = 0.014), and this decreased expression coexisted with impaired IFN-gamma (42.4 +/- 43.2 pg/ml versus 1,757.4 +/- 2449.0 pg/ml; P = 0.031) and tumor necrosis factor alpha (682.6 +/- 519.3 pg/ml versus 1,686.0 +/- 1,533.7 pg/ml; P = 0.041) production of T cells. Thus, peripheral blood T cells from gastric cancer patients simultaneously exhibit an elevated caspase-3 activity, an increased degree of T-cell apoptosis, a down-regulation of TCR-zeta molecules, and impaired cytokine production. These observations suggest that induction of T-cell apoptosis coexisting with a down-regulation of TCR-zeta molecules may be responsible for T-cell dysfunction in patients with gastric cancer.
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PMID:Elevated caspase-3 activity in peripheral blood T cells coexists with increased degree of T-cell apoptosis and down-regulation of TCR zeta molecules in patients with gastric cancer. 1120 21

Although debates still exist whether Helicobacter pylori infection is really class I carcinogen or not, H. pylori has been known to provoke precancerous lesions like gastric adenoma and chronic atrophic gastritis with intestinal metaplasia as well as gastric cancer. Chronic persistent, uncontrolled gastric inflammations are possible basis for ensuing gastric carcinogenesis and H. pylori infection increased COX-2 expressions, which might be the one of the mechanisms leading to gastric cancer. To know the implication of long-term treatment of antiinflammatory drugs, rebamipide or nimesulide, on H. pylori-associated gastric carcinogenesis, we infected C57BL/6 mice with H. pylori, especially after MNU administration to promote carcinogenesis and the effects of the long-term administration of rebamipide or nimesulide were evaluated. C57BL/6 mice were sacrificed 50 weeks after H. pylori infection. Colonization rates of H. pylori, degree of gastric inflammation and other pathological changes including atrophic gastritis and metaplasia, serum levels and mRNA transcripts of various mouse cytokines and chemokines, and NF-kappaB binding activities, and finally the presence of gastric adenocarcinoma were compared between H. pylori infected group (HP), and H. pylori infected group administered with long-term rebamipide containing pellet diets (HPR) or nimesulide mixed pellets (HPN). Gastric mucosal expressions of ICAM-1, HCAM, MMP, and transcriptional regulations of NF-kappaB binding were all significantly decreased in HPR group than in HP group. Multi-probe RNase protection assay showed the significantly decreased mRNA levels of apoptosis related genes and various cytokines genes like IFN-gamma, RANTES, TNF-alpha, TNFR p75, IL-1beta in HPR group. In the experiment designed to provoke gastric cancer through MNU treatment with H. pylori infection, the incidence of gastric carcinoma was not changed between HP and HPR group, but significantly decreased in HPN group, suggesting the chemoprevention of H. pylori-associated gastric carcinogenesis by COX-2 inhibition. Long-term administration of antiinflammatory drugs should be considered in the treatment of H. pylori since they showed the molecular and biologic advantages with possible chemopreventive effect against H. pylori-associated gastric carcinogenesis. If the final concrete proof showing the causal relationship between H. pylori infection and gastric carcinogenesis could be obtained, that will shed new light on chemoprevention of gastric cancer, that is, that gastric cancer could be prevented through either the eradication of H. pylori or lessening the inflammation provoked by H. pylori infection in high risk group.
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PMID:Chemoprevention of Helicobacter pylori-associated gastric carcinogenesis in a mouse model: is it possible? 1254 79

Tumor-reactive effector lymphocytes were generated using tumor-derived amplified RNA and cultured dendritic cells (DC). Tumor RNAs were extracted from gastric cancer cell line MKN45 or cancer cells of malignant effusions, and were processed with T7 amplification. DCs were induced from an adherent cell population of peripheral blood mononuclear cells (PBMCs) with GM-CSF and IL-4. Tumor-RNA was introduced into DCs using electroporation. Effector cells were generated by stimulating a non-adherent fraction of PBMCs with tumor RNA-introduced DCs. It was observed that milligram RNA could efficiently be amplified from microgram RNA. The effector cells, designated as tumor-RNA-introduced DC-activated killer (TRiDAK) cells, showed IFN-gamma spots in a tumor-specific manner when examined using ELISPOT analysis, and demonstrated cytotoxic activities against tumor cells from which RNA was extracted. TRiDAK cells produced more tumor-specific IFN-gamma spots when stimulated repeatedly. These results suggest that TRiDAK cells are practical and may be effective lymphocytes for adoptive cancer immunotherapy.
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PMID:[Generation of TRiDAK (tumor RNA-introduced dendritic cell-activated killer) cells]. 1461 26

Experimental infection with Helicobacter pylori in Mongolian gerbils results in chronic gastritis and gastric cancer. To investigate epithelial cell proliferation, apoptosis, and mucosal cytokine responses in gastritis, Mongolian gerbils were infected with the H pylori SS1 strain. At 4 weeks post-infection, gastritis was predominantly within the antrum, but extended to the corpus in approximately 50% of gerbils by 36 weeks. Epithelial cell proliferation and apoptosis in glandular epithelial cells were increased with infection. Antral cell proliferation, but not apoptosis, correlated significantly with gastric inflammation. In female gerbils, H pylori significantly increased expression of transcripts for IFN-gamma and IL-12p40, but not TGF-beta or IL-10, in the gastric mucosa. Significantly reduced IFN-gamma and IL-12p40 responses were observed in male gerbils infected with H pylori, but epithelial proliferative and apoptotic responses were comparable to those of females. These studies demonstrate that the female gerbil cytokine response to H pylori has a Th1 profile and that there are gender differences in the magnitude of the gastric cytokine responses to H pylori. The absence of a down-regulatory cytokine response may account for the more severe gastritis observed with H pylori infection in gerbils than in mice.
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PMID:Gastric mucosal cytokine and epithelial cell responses to Helicobacter pylori infection in Mongolian gerbils. 1474 2

Locoregional administration of the streptococcal preparation OK-432 is effective in treating malignant ascites from gastric cancer. In order to enhance the efficacy, we conducted a pilot study of locoregional immunotherapy for malignant ascites using host-oriented doses of OK-432. Moreover, action mechanisms of OK-432 were further explored in view of the T-helper type 1 (Th1)-Th2 concept. Gastric cancer patients with cytologically determined malignant ascites were locoregionally administered with OK-432. The dose of OK-432 was selected according to the delayed-type hypersensitivity (DTH) reaction levels to OK-432. Cytokine production profiles of ascites cells were determined using whole ascites assay by stimulation with OK-432. IL-10 mRNA expression was analyzed using RT-PCR. It was found that a positive clinical response was observed in 37 of the 51 (73%) patients with the DTH-oriented approach, showing a significantly higher efficacy than traditional dosage methods using empirical doses (31/58, 53%) (p=0.0487). The DTH-oriented administration of OK-432 produced adverse effects such as fever elevation (p<0.0001) and abdominal pain (p=0.0013) to a significantly lesser extent compared with the traditional treatment. Analysis of the action mechanism of OK-432 revealed that the DTH reaction in responders (19+/-6 mm) was stronger than that in non-responders (6+/-4 mm) (p<0.0001). Tumor necrosis factor (TNF)-alpha production of ascites cells was also higher in responders (3943+/-1247 pg/ml) than in non-responders (1217+/-939 pg/ml) (p=0.0002). There was a significant positive correlation (p=0.0085) between the levels of DTH reaction and TNF-alpha production of ascites cells, but not of blood cells. Responders appeared to polarize on the Th1 axis when clinical responses were plotted on Th1-Th2 dimensions according to the cytokine production profiles of TNF-alpha, IFN-gamma, IL-4 and IL-6 of ascites cells. In vitro culture with IL-2 of ascites cells after OK-432 administration demonstrated an almost clonal expansion of CD4+ lymphocytes, which produced TNF-alpha and IFN-gamma, but did not produce IL-4 or IL-6. IL-10 mRNA expression was detectable in ascites cells from non-responders before treatment. These results suggest that the DTH-oriented locoregional administration of OK-432 may be both effective and less toxic in treating malignant ascites from gastric cancer, showing a possibility of the tailored immunotherapy for malignant ascites. Th1 dysfunction exists in the microenvironment of malignant ascites from gastric cancer, in which IL-10 may, in part, play a role. The up-regulation of Th1 responses by OK-432 may result in positive clinical responses. The DTH reaction to OK-432 may be a useful tool not only for predicting clinical response but also for selecting the optimal dose of OK-432.
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PMID:Locoregional immunotherapy of malignant ascites from gastric cancer using DTH-oriented doses of the streptococcal preparation OK-432: Treatment of Th1 dysfunction in the ascites microenvironment. 1501 Aug 36

Biological response modifiers (BRMs) augment the cytotoxic activity of various effector cells by the induction of multiple cytokines and suppression of immunosuppressive factors. BRMs are used extensively in adjuvant therapy for gastric cancer in Japan. In dendritic cell (DC)-based vaccine therapy, the quality of DCs is important in inducing strong antitumor immunity. A good manufacturing practice (GMP) grade agent for DCs maturation is desirable for safety. Here we report the effects of two BRMs, OK432 and PSK, which are GMP grade agents for the functional maturation of DCs. OK432 and PSK were examined in vitro, and compared with lipopolysaccharide (LPS) and a cytokine cocktail (IL-1beta, TNF-alpha, IL-6 and PGE2). In the immunophenotypical analysis, the expression of CD80 and CD83 of DCs stimulated with OK-432 increased significantly compared with PSK and medium, and this up-regulation was the same as levels of DCs stimulated with cytokine cocktail. DCs stimulated with OK-432 showed significantly higher production of IL-12 and Th1-type cytokines (IL-2 and IFN-gamma) compared with DCs stimulated with LPS or cytokine cocktail. OK-432 stimulated DCs could induce the significantly high level of cytotoxic T cell activity compared with PSK-stimulated or unstimulated DCs. These results suggest that OK432 is a GMP-grade reagent that promotes functional maturation of DCs and could be applied in DC-based vaccinations.
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PMID:Usefulness of immunomodulators for maturation of dendritic cells. 1525 44

Autologous tumor cells stimulated with T lymphocytes (AuTL) were generated ex vivo from peripheral blood lymphocytes over a two-week co-culturing process with autologous tumor cells. These AuTLs were capable of lysing established tumor cell lines and may have a potential for efficacy as an adoptive immunotherapy (IT) in advanced and metastatic refractory cancer patients (pts). We investigated the feasibility of a combination of AuTL transfer and chemotherapy (ChT) based on the conventional conditioning regimen in order to take advantage by both the anticancer effects and reconstruction of antitumor immunity. Nineteen patients were enrolled in a pilot clinical trial. The two administrations of AuTL were given prior to chemotherapy (ChT) for one treatment cycle. The treatment was repeated at least for three cycles over a one-week interval. The conventional ChT regimen was based on the standard dosage. The pts consisted of 3 of gastric cancer, colon cancer, lung adenocarcinoma, respectively, 6 of esophageal cancer, and 2 of breast and pancreas carcinoma, respectively. AuTLs were administered 1x/2 weeks using direct injection or intraarterial infusion. The median duration of the treatment was over 11.5 months, and the median survival time was 14.8 months. Adverse events related to both the ChT and AuTL transfers at all dosages were minimal. Four of the 13 pts achieved major tumor responses (2 CR: complete regression and 2 PR: partial regression) in this study. Three pts showed progressive disease, and 6 pts had stable disease for over 90 days. PBMC were evaluated for cytokine production prior to the treatment and after 3 treatments. Two and one of 4 CR/PR pts had increased IFN-gamma and TNF-alpha production with no TGF-beta1 responses by their PBMC after 3 treatments, respectively. Two out of 6 pts who experienced stable disease after the treatment had high IFN-gamma and TNF-alpha responses and no TGF-beta1 or IL-4 response. TGF-beta1 and IL-4 secretion increased in parallel in 3 out of 3 pts that experienced progressive disease after the treatment. These data show that combination therapy of AuTL transfer and non-myeloablative ChT is a feasible option for patients with refractory advanced cancers without serious adverse events and without reducing Th1 cytokine responses in peripheral blood for most of the pts that responded to the treatment. According to each mechanism of IT and ChT, a more stringent evaluation of AuTL transfer combined with non-myeloablative ChT for various kinds of cancers should be performed to manage the immunodeficiency in the pts with advanced cancer and to improve the effect of antitumor AuTLs.
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PMID:[The repetitive immune cell transfer therapy combining non-myelosuppressive chemotherapy for patients with advanced and refractory cancer]. 1555 72

CpG oligodeoxynucleotides (CpG ODN) have been shown to have potent adjuvant activity for a wide range of antigens. Of particular interest is their improved activity when closely associated with the antigen. The purpose of this study is to construct a nanovaccine coencapsulated with a gastric cancer specific antigen MG7 mimotope peptide and adjuvant CpG ODN 1645 using new nanotechnology as nanoemulsion and evaluate its immunocompetence. Nanoemulsion vaccine was prepared using magnetic ultrasound methods. BALB/c mice were immunized and the in vivo effectiveness was evaluated using tumor challenge assay. It was shown that the tumor masses formed in the mice immunized with coencapsulated nanovaccine (0.0825 g) markedly smaller (P < 0.01) than those formed in the mice immunized with nanovaccine encapsulated with antigen peptide alone (0.4465 g). A tumor inhibiting rate as high as 82.5% of the coencapsulated nanovaccine was obtained, while nanovaccine encapsulated with peptide only could not achieve the same effect (28.5%) (P < 0.01). Enzyme-linked immunospot assay (ELISPOT) showed that immunization using MG7 mimotope peptide coencapsulated with CpG ODN within the same nanoemulsion enhanced the frequency of splenocytes secreting IFN-gamma significantly (P < 0.01) when compared with immunization using MG7 peptide encapsulated in nanoemulsion alone (197spots/1 x 10(6) vs. 73 spots/1 x 10(6)). Cellular ELISA indicated that serum titer of antibody against MG7-Ag was significantly higher (P < 0.01) in mice immunized with coencapsulation form nanovaccine (0.7884) than that in the group immunized with nanovaccine encapsulated with MG7 peptide alone (0.3616). Using intracellular flow cytometric analysis, it was found that the IFN-gamma response was contributed by CD4+ T-cells. Our experiments suggest that a vaccinal approach using nano-delivery system carrying in tumoral epitope and CpG ODN as adjuvant may have important implications for cancer therapy.
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PMID:Enhanced immune response to gastric cancer specific antigen Peptide by coencapsulation with CpG oligodeoxynucleotides in nanoemulsion. 1575 59


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