• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.1
• /
• pp.117-122
• /
• 2012

Aim: To elucidate the effects of hyperthermic $CO_2$ pneumoperitoneum on human gastric AGS cells. Methods: Based on a newly devised in vitro study model, we evaluated the anti-cancer effects of HT-$CO_2$ ($42-44^{\circ}C$ for 2-4h) on human gastric cancer cells, and also the corresponding mechanisms. Results: HT-$CO_2$ ($42-44^{\circ}C$ for 2-4h) severely inhibited cell proliferation as assessed by Cell Counting Kit-8 assay, while inducing apoptosis in a temperature- and time-dependent manner demonstrated by annexin-V/PI flow cytometry and morphological analysis (Hoechst/PI fluorescence). In addition, it was found that HT-$CO_2$ ($42-44^{\circ}C$ for 2-4h) promoted the up-regulation of Bax by western blotting. Significantly, it could also suppress gastric cancer cell invasion and metastasis by in vitro invasion and motility assay. Conclusion: In conclusion, HT-$CO_2$ had an efficacious cytotoxic effect on gastric cancer cells through Bax-induced mitochondrial apoptotic signaling. Our studies indicate that it may serve as a potential therapy for peritoneal carcinomatosis of gastric cancer. Further investigations in vivo using animal models are now urgently needed.

• BMB Reports
• /
• v.52 no.11
• /
• pp.647-652
• /
• 2019

G protein-coupled estrogen receptor (GPER) is known to play an important role in hormone-associated cancers. G-1, a novel synthetic GPER agonist, has been reported to exhibit anti-carcinogenic properties. However, the chemotherapeutic mechanism of GPER is yet unclear. Here, we evaluated GPER expression in human gastric cancer tissues and cells. We found that G-1 treatment attenuates GPER expression in gastric cancer. GPER expression increased G-1-induced antitumor effects in mouse xenograft model. We analyzed the effects of knockdown/overexpression of GPER on G-1-induced cell death in cancer cells. Increased GPER expression in human gastric cancer cells increased G-1-induced cell death via increased levels of cleaved caspase-3, -9, and cleaved poly ADP-ribose polymerase. Interestingly, during G-1-induced cell death, GPER mRNA and protein expression was attenuated and associated with ER stress-induced expression of PERK, ATF-4, GRP-78, and CHOP. Furthermore, PERK-dependent induction of ER stress activation increased G-1-induced cell death, whereas PERK silencing decreased cell death and increased drug sensitivity. Taken together, the data suggest that the induction of ER stress via GPER expression may increase G-1-induced cell death in gastric cancer cells. These results may contribute to a new paradigm shift in gastric cancer therapy.

• BMB Reports
• /
• v.55 no.7
• /
• pp.348-353
• /
• 2022

Gastrointestinal cancer is associated with a high mortality rate. Here, we report that the splice variant of NRP/B contributes to tumorigenic activity in highly malignant gastric cancer through dissociation from the tumor repressor, HDAC5. NRP/B mRNA expression is significantly higher in the human gastric cancer tissues than in the normal tissues. Further, high levels of both the NRP/B splice variant and Lgr5, but not the full-length protein, are found in highly tumorigenic gastric tumor cells, but not in non-tumorigenic cells. The loss of NRP/B markedly inhibits cell migration and invasion, which reduces tumor formation in vivo. Importantly, the inhibition of alternative splicing increases the levels of NRP/B-1 mRNA and protein in AGS cells. The ectopic expression of full-length NRP/B exhibits tumor-suppressive activity, whereas NRP/B-2 induces the noninvasive human gastric cancer cells tumorigenesis. The splice variant NRP/B-2 which loses the capacity to interact with tumor repressors promoted oncogenic activity, suggesting that the BTB/POZ domain in the N-terminus has a crucial role in the suppression of gastric cancer. Therefore, the regulation of alternative splicing of the NRP/B gene is a potential novel target for the treatment of gastrointestinal cancer.

• Anatomy and Cell Biology
• /
• v.57 no.1
• /
• pp.105-118
• /
• 2024

The world has witnessed tremendous advancements in nano-base applications. Zinc oxide nanoparticles (ZON) are widely used in food industry and medicine. Although their application is of important value, they may cause toxicity to body tissues. Peripheral blood mononuclear cells (PBMCs) proved its efficacy in tissue regeneration especially when it is preconditioned by activated platelet supernatant (APS). The aim of this study is to evaluate the effect of ZON on the gastric mucosa and the therapeutic role of the PBMCs preconditioned by APS in rats. Ten rats were donors and fifty rats were recipients. The recipients were divided into; control group, ZON group (10 mg/kg/day orally for five days) and preconditioned PBMCs group (1×10⁷ once intravenously 24 hours after ZON). Gastric specimens were processed for histological, immunohistochemical, biochemical and quantitative real-time polymerase chain reaction studies. ZON group showed marked structural changes in the gastric mucosa. There was desquamation or deep ulceration of the epithelium. Cytoplasmic vacuoles and pyknotic nuclei were in glandular cells. Reduced proliferating cell nuclear antigen and increased tumor necrosis factor-α were in epithelial cells. There were significant elevation in malondialdahyde and reduction in glutathione, superoxide dismutase, and catalase. Enhancement in mRNA expression of nuclear factor kappa-B and cyclooxygenase-2 was detected. The preconditioned PBMCs group showed significant improvement of all parameters. So, ZON had cytotoxic effects on the gastric mucosa and the preconditioned PBMCs had a therapeutic effect on gastric mucosal damage after ZON.

• Molecular & Cellular Toxicology
• /
• v.3 no.1
• /
• pp.31-35
• /
• 2007

Hesperidin, known as a flavonoid constituent of citrus, has been known to reduce the proliferation of several cancer cells. We investigated whether hesperidin-induced cell death on SNU-668, human gastric cancer cells. The cytotoxicity of hesperidin on SNU-668 cells was determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay at the concentration of 1, 10, 50, and 100 ${\mu}M$. Cell viability by hesperidin was 53.18$\pm$2.85% of control value at 100 ${\mu}M$. The cell death by hesperidin showed apoptotic features, which were confirmed using a combination of 4, 6-diamidino-2-phenylindole (DAPI) staining and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay. In the apoptosis-regulating genes, treatment of hesperidin decreased mRNA expression of B-cell CLL/lymphoma 2 (BCL2), whereas expression of BCL2-associated X protein (BAX) was increased. The mRNA expression and the activity of caspase3 (CASP3), a major apoptotic factor, was significantly increased by hesperidin treatment. These results suggest that hesperidin could induce apoptosis through CASP3 activation on SNU-668, human gastric cancer cells.

• The Korean Journal of Food And Nutrition
• /
• v.24 no.2
• /
• pp.258-267
• /
• 2011

14-3-3 is a highly conserved, ubiquitously expressed protein family. It associates with diverse cellular proteins through its specific phosphoserine/phosphothreonine-binding activity and thus contributes to the regulation of crucial cellular processes such as metabolism, signal transduction, cell-cycle control, apoptosis, protein trafficking, transcription and stress responses. This study aims to determine changes in levels of 14-3-3 isoforms and 14-3-3 - associated proteins in Helicobacter pylori(H. pylori)-infected gastric epithelial AGS cells. AGS cells were stimulated with H. pylori(NCTC 11637) at the ratio of 300:1(bacterium:cell). Western blot analysis revealed that 14-3-3 $\sigma$ was elevated at 3 hr after H. pylori treatment. Other isoforms were not significantly affected by H. pylori infection. Using immunoprecipitation to 14-3-3 $\sigma$, followed by proteomic analysis, we found that S phase kinase associated protein isoform 2 bound to 14-3-3 $\sigma$ has increased. In contrast, three proteins (DEAD-box polypeptide 3, heterogeneous nuclear ribonucleoprotein H2 and WD repeat-containing protein isoform 1) bound to 14-3-3 decreased by H. pylori infection. Our results suggest that 14-3-3 may play an important regulatory role in H. pylori-induced signal transduction in gastric epithelial cells.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.9
• /
• pp.1485-1492
• /
• 2015

Makgeolli is a traditional wine in Korea and has been traditionally believed to exhibit health benefits. However, the inhibitory effect of dealcoholized makgeolli (MK) on cancer has never been investigated scientifically. In this study, MK exhibited an anti-angiogenic effect by inhibiting tube formation in human umbilical vein endothelial cells, without cytotoxicity. Treatment with MK reduced the proliferation of AGS human gastric adenocarcinoma cells in a dose-dependent manner and increased the sub-G1 population. Next, we evaluated whether MK could induce apoptosis in AGS cells by using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay or Annexin V method. Treatment with MK at 500 and 1,000 μg/ml increased the number of TUNEL-positive AGS cells. Under the same conditions, MK-treated (500 and 1,000 μg/ml) cells showed significant induction of early or late apoptosis, compared with untreated cells (no induction). In addition, MK also induced phosphatase and tensin homolog (PTEN) expression in AGS cells. However, p53 expression in AGS cells was not changed by MK treatment. Furthermore, MK at 500 mg/kg·d reduced the tumor size and volume in AGS tumor xenografts. Taken together, MK may be useful for the prevention of cancer cell growth.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.6
• /
• pp.1326-1331
• /
• 1999

In vitro anticancer effect of Chinese cabbage kimchi fractions was investigated by using human cancer cells, AGS human gastric adenocarcinoma cells and HT 29 human colon adenocarcinoma cells. The Chinese cabbage kimchi(fermented for 4 days at 15oC) was fractionated into 7 groups, methanol extract, hexane fraction(fr.), methanol soluble fr., dichloromethane fr., ethylacetate fr., butanol fr. and aqueous fr.. Chinese cabbage kimchi fractions inhibited the growth of AGS and HT 29 cancer cells as dose dependent. In particular, the dichloromethane fr. showed the highest inhibitory effect among other fractions. When the dichloromethane fr.(0.2mg/ml) was treated, the number of AGS and HT 29 survival cancer cells reduced to 12$\times$104/ml and 11$\times$104/ml compared to 166$\times$104/ml and 50$\times$104/ml of the controls, respectively. Chinese cabbage kimchi fractions also inhibited the DNA synthesis of the cancer cells. They inhibited the DNA synthesis of AGS human gastric adenocarcinoma cells more efficiently than that of HT 29 human colon adenocarcinoma cells. These results indicate that Chinese cabbage kimchi fractions show in vitro anticancer activity and the dichloromethane fr. among them reveals the highest effect.

• BMB Reports
• /
• v.47 no.1
• /
• pp.39-44
• /
• 2014

Increasing data shows miR-29a is a key regulator of oncogenic processes. It is significantly down-regulated in some kind of human tumors and possibly functionally linked to cellular proliferation, survival and migration. However, the mechanism remains unclear. In this study, we report miR-29a is significantly under-expressed in gastric cancer compared to the healthy donor. The microvessel density is negatively related to miR-29a expression in gastric cancer tissues. The ectopic expression of miR-29a significantly inhibits proliferation and invasion of gastric cancer cells. Furthermore, western blot combined with the luciferase reporter assays demonstrate that vascular endothelial growth factor A (VEGF-A) is direct target of miR-29a. This is the first time miR-29a was found to suppress the tumor microvessel density in gastric cancer by targeting VEGF-A. Taken together, these results suggest that miR-29a is a tumor suppressor in gastric cancer. Restoration of miR-29a in gastric cancer may be a promising therapeutic approach.

• KSBB Journal
• /
• v.32 no.2
• /
• pp.83-89
• /
• 2017

Gamma (${\gamma}$)-oryzanol is a substance abundant in rice, which is widely cultivated in Asian countries. In this study, we evaluated the effect of ${\gamma}$-oryzanol treatment on proliferation and apoptosis of AGS human gastric carcinoma cells. AGS cells were treated with ${\gamma}$-oryzanol for 72 h in a dose dependent manner. Treatment of ${\gamma}$-oryzanol (50, 100, and $200{\mu}g/mL$) resulted in decreased AGS cell proliferation and increased number of cells in the sub-G1 population. Additionally, apoptotic cells were investigated by annexin V staining and mitochondrial membrane potential assays. Our results indicated that ${\gamma}$-oryzanol treatment increased the number of annexin V-positive cells and depolarized cells. This demonstrated that ${\gamma}$-oryzanol is effective for the induction of apoptosis in AGS cells. We next examined the expression of promising anticancer drug target molecules, including PTEN and HSP90. We found that treatment of ${\gamma}$-oryzanol induced the expression of PTEN in AGS cells. Under the same treatment conditions, ${\gamma}$-oryzanol reduced the expression of HSP90 in AGS cells. These results suggest that ${\gamma}$-oryzanol-induced apoptosis was accompanied by changes in regulation of PTEN and HSP90 in AGS cells. Taken together, ${\gamma}$-oryzanol could be used as a functional substance for the prevention of gastric cancer.