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Context: Squalene epoxidase (SQLE) is overexpressed in a variety of tumors, which may play an important role in their tumorigenesis, development, and prognosis., Aims: The aim of this study is to investigate the expression of SQLE and explore its clinicopathological significance in gastric cancer., Settings and Design: The correlation between its positive expression and the pathological characteristics of patients (such as sex, age, tumor size, survival, tumor differentiation, TNM staging, and lymph node metastasis) was analyzed., Materials and Methods: Immunohistochemical method was used to detect its expression in 107 cases of gastric carcinoma and 34 cases of tumor-adjacent tissues., Statistical Analysis Used: Counting data were analyzed by Chi-square test. Its overall survival was analyzed by Kaplan-Meier method and log-rank test. Its hazard factors were analyzed by Cox multivariate analysis., Results: The positive rate of SQLE in gastric cancer is 67.3%, which is higher than that in tumor-adjacent tissues (17.6%), <0.001. Expression of SQLE is closely related to tumor differentiation, TNM staging and lymph node metastasis (P = 0.030, P = 0.009, and P = 0.011, respectively). Furthermore, compared with those low expression of SQLE, the patients of overexpression had worse overall survival by Kaplan-Meier analysis (P = 0.025). Cox multivariate analysis shows that lymph node metastasis, tumor differentiation, SQLE, and TNM staging are independent factors for prognosis of gastric cancer (P = 0.003, 0.020, 0.018, and P = 0.001 respectively)., Conclusions: SQLE is overexpressed in gastric cancer. It could be used for the diagnosis and prognosis of the gastric cancer patients.

T-2 toxin is one of the most toxic trichothecenes and harmful to human health and animal husbandry. The mechanism underlying its growth suppression remains unclear, especially for mitochondrial damage in human gastric epithelial cells. In the present study, we investigated cell death caused by T-2 toxin in a human gastric epithelial cell line (GES-1) and the possible mechanism of T-2-induced cytotoxicity. T-2 strongly reduced the viability of GES-1 cells in a time- and dose-dependent manner within a small range of concentrations. However, when the concentrations of T-2 were >40 nM, there was no concentration dependence, only time dependence. Moreover, T-2 induced apoptosis, with the activation of caspase-3 in GES-1 and mitochondrial membrane potential (MMP) decrease and cytochrome c release. T-2 also resulted in the accumulation of reactive oxygen species (ROS) and DNA damage with a positive signal of p-H2A.X in GES-1 cells. While T-2 caused a MMP decrease, DNA damage and cell death were not blocked by pretreatment with 3 mM glutathione (GSH), a typical scavenger of ROS. The induction of mitochondrial permeability transition pore (mPTP) regulators voltage-dependent anion channel (VDAC1) and cyclophilin D (CypD) were also observed in T-2-treated cells. Interestingly, cyclosporine A (CsA), a CypD inhibitor, significantly reversed the drop in MMP and the DNA damage, as well as ROS accumulation caused by T-2. Additionally, GES-1 cell death could also be protected to some extent by 4, 4'-diisothiocyanatostilbene-2, 2'-disulfonic acid (DIDS), an inhibitor of VDAC1, especially the combination of CsA and DIDS, and 3 mM GSH could further enhance the effect of CsA + DIDS on cell viability. In conclusion, our present findings indicate that the T-2 induced MMP decrease, DNA damage and cell death, as well as ROS accumulation in GES-1 cells, starts with T-2 directly perturbing the mitochondria triggering ROS generation by acting on CypD and VDAC1. This study presents a new viewpoint for evaluating the toxicity of T-2 toxin., (© 2020 John Wiley & Sons, Ltd.)

Targeting mitochondria using proper pharmacological agents is considered an attractive strategy for cancer control and management. Herein, we report a newly synthetic triazole analog of Jaridonin, DN3, which exhibits more potent antitumor activity via acting directly on mitochondria. DN3 potently reduced viabilities of gastric cancer cell lines HGC-27 and MGC-803 through inducing apoptosis and cell cycle arrest. But, normal human gastric epithelial cell line GES-1 is more resistant to the growth inhibition by DN3 compared with gastric cancer cells. DN3 induced mitochondrial membrane potential (MMP) decrease and cytochrome c release in intact gastric cancer cell lines. Meanwhile, the DN3 treatment also caused the release of cytochrome c from mitochondria isolated from cancer cell lines in a mitochondrial permeability transition pore complex (PTPC) mediated manner, but not from mitochondria isolated from normal gastric epithelial cell. The induction of mitochondrial PTPC proteins voltage-dependent anion channel (VDAC) and cyclophilin D (CypD) were also observed in DN3-treated cells. More interestingly, DN3 mediated MMP decrease, release of cytochrome c, the expression of VDAC and CypD and apoptosis were blocked by the pretreatment of VDAC1 inhibitor (4, 4'-diisothiocyanatostilbene-2,2'-disulfonic acid, DIDS) and CypD inhibitor (cyclosporine A, CsA). In a mouse xenograft model of human gastric cancer, the treatment of 5 mg/kg DN3 led to significant tumor regression without affecting body weight. In conclusion, our findings indicate that DN3 is a potential agent for the treatment of gastric cancer through acting directly on mitochondria, and would be useful for us to design more and better anti-cancer compounds., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objective: To investigate the effects and the underlying mechanism of DS2, a newly synthetic analog of natural ent-kaurane diterpenoid, on the proliferation and migration capabilities of human gastric cancer cells. Methods: MTT assay, colony formation assay and flow cytometry were used to measure the effects of DS2 on growth, apoptosis and cell cycle of several human gastric cancer cell lines. The function of DS2 in the migration was further detected by wound healing and transwell assays. The expression of migration related proteins were determined by western blot. Results: DS2 inhibited the growth of MGC-803, SGC-7901 and HGC-27 cells in a dose dependent manner. After treatment of DS2 at a concentration of 6.25 μmol/L for 24 h, the survival rates of MGC-803, SGC-7901 and HGC-27 cells were 53.87±3.05%, 55.91±6.97% and 32.41±2.64%, respectively. However, for the normal gastric epithelial cell GES-1, no obvious growth inhibition was observed. In addition, DS2 caused significant G(2)/M arrest and induced apoptosis in MGC-803 cells. Furthermore, compared with the negative control, the colony formation, wound healing rate as well as the number of migrating cells of MGC-803 were significantly decreased in a dose dependent manner after DS2 treatment. DS2 induced the expression of E-cadherin, whereas β-catenin and N-cadherin levels were downregulated in MGC-803. Conclusion: The new compound DS2 has a strong anti-cancer activity, and this study will help us to design and synthesize better diterpenoids derivatives.

Objective: To study the effects of Jaridonin, a novel diterpenoid from isodon rubescens, on the cell cycle of human gastric cancer cells and its molecular mechanism of action., Methods: Flow cytometry was used to analyze the cell cycle distribution and expression of ataxia telangiectasia mutated kinase (ATM) after Jaridonin treatment. Western blot was performed to detect the expression of cell cycle-related proteins., Results: The results of flow cytometry showed that the percentages of MGC-803 cells in G(2)/M phase at 6 hours after 0, 10, 20 μmol/L Jaridonin-treatment were (10.8±2.2)%, (18.2±2.5)%, (27.3±3.2)%, respectively; those at 12 hours after Jaridonin-treatment were (12.0±1.5)%, (24.1±2.0)% and (39.7±5.2)%, respectively, indicating a G2/M phase arrest of MGC-803 cells was resulted in a time- and dose-dependent manner. The expressions of ATM, Chk1, Chk2, phosphorylated Cdc2 and CDK2 were up-regulated in the MGC-803 cells after Jaridonin treatment, while the levels of Cdc2 and CDK2 were decreased. KU-55933, an inhibitor of ATM, reversed the expression of relevant proteins and G(2)/M phase arrest induced by Jaridonin., Conclusions: Jaridonin can significantly induce G(2)/M arrest in gastric cancer MGC-803 cells. Its mechanism may be related to the activation of ATM and Chk1/2, and inactivation of Cdc2 and CDK2 phosphorylation.

Aim: To investigate the differentiated whole genome expression profiling of gastric high- and low-grade intraepithelial neoplasia and early-stage adenocarcinoma., Methods: Gastric specimens from an upper magnifying chromoendoscopic targeted biopsy were collected from March 2010 to May 2013. Whole genome expression profiling was performed on 19 low-grade intraepithelial neoplasia (LGIN), 20 high-grade intraepithelial neoplasia (HGIN), 19 early-stage adenocarcinoma (EGC), and 19 chronic gastritis tissue samples using Agilent 4 × 44K Whole Human Genome microarrays. Differentially expressed genes between different types of lesions were identified using an unpaired t-test and corrected with the Benjamini and Hochberg false discovery rate algorithm. A gene ontology (GO) enrichment analysis was performed using the GeneSpring software GX 12.6. The differentially expressed gene was verified using a real-time TaqMan® PCR assay with independent tissue samples, including 26 LGIN, 15 HGIN, 14 EGC, and 20 chronic gastritis. The expression of G0S2 were further validated by immunohistochemical staining (IHC) in 24 LGIN, 40 HGIN, 30 EGC and 61 chronic gastritis specimens., Results: The gene expression patterns of LGIN and HGIN tissues were distinct. There were 2521 significantly differentially expressed transcripts in HGIN, with 951 upregulated and 1570 downregulated. A GO enrichment analysis demonstrated that the most striking overexpressed transcripts in HGIN compared with LGIN were in the category of metabolism, defense response, and nuclear factor κB (NF-κB) cascade. While the vast majority of transcripts had barely altered expression in HGIN and EGC tissues, only 38 transcripts were upregulated in EGC. A GO enrichment analysis revealed that the alterations of the immune response were most prominent in the progression from HGIN to EGC. It is worth noting that, compared with LGIN, 289 transcripts were expressed at higher levels both in HGIN and EGC. A characteristic gene, G0/G1 switch 2 (G0S2) was one of the 289 transcripts and related to metabolism, the immune response, and the NF-κB cascade, and its expression was validated in independent samples through real-time TaqMan® PCR and immunohistochemical staining. In real-time PCR analysis, the expression of G0S2 was elevated both in HGIN and EGC compared with that in LGIN (P < 0.01 and P < 0.001, respectively). In IHC analysis, G0S2 immunoreactivity was detected in the cytoplasmic of neoplastic cells, but was undetectable in chronic gastritis cells. The G0S2 expression in HGIN was higher than that of LGIN (P = 0.012, χ (2) = 6.28) and EGC (P = 0.008, χ (2) = 6.94)., Conclusion: A clear biological distinction between gastric high- and low-grade intraepithelial neoplasia was identified, and provides molecular evidence for clinical application.

Aim: To investigate the clinical epidemiological characteristics of gastric cancer in the Hehuang valley, China, to provide a reference for treatment and prevention of regional gastric cancer., Methods: Between February 2003 and February 2013, the records of 2419 patients with gastric cancer were included in this study. The patient's characteristics, histological and pathological features, as well as the dietary habits of the patients, were investigated., Results: The clinical data showed that adenocarcinoma was the leading histological type of gastric cancer in this area. Characteristics of gastric cancer in different ethnic groups and age showed that the 60.55-65.50 years group showed the high incidence of gastric cancer in all ethnic groups. There were more male gastric cancer patients than female. Intestinal was the most common type of gastric cancer in the Hehuang valley. There was no significant difference in the proportion of sex in terms of Helicobacter pylori infection. The impact of dietary habits on gastric cancer showed that regular consumption of fried or grilled food, consumption of high-salt, high-fat and spicy food and drinking strong Boiled brick-tea were three important factors associated with gastric cancer in males and females., Conclusion: Differences existed in race, sex, and age of patients according to the epidemiology of gastric cancer in the Hehuang valley. Moreover, dietary habits was also an important factor contributing to gastric cancer.

Background and Aim: This study investigated whether 19-peptide, a fragment of tumstatin, inhibited the growth of gastric tumor cells in vitro and in vivo., Methods: 19-peptide was expressed in bacteria and purified with Sephadex G-15. SGC7901 gastric carcinoma cells and human umbilical-vein endothelial cells (HUVECs) were exposed to 19-peptide in vitro, and their viability was evaluated by biochemical and histopathological analysis. In vivo, pieces of solid tumor derived from SGC7901 cells were inoculated into the gastric serosa of 36 nude mice, with a biological glue to hold them in place. Twenty-eight days after injection of 19-peptide, the mice were killed. The tumors were measured and examined by western blotting, histopathology, and terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling assay., Results: 19-peptide induced apoptosis of many SGC7901 cells but few HUVECs in vitro. In vivo, after the application of 19-peptide, significant tumor cell apoptosis was observed in the center of the tumors, tumor volume was reduced significantly (P < 0.001), and the invasion and migration of cancer cells was reduced. PTEN was increased in the treatment group and phospho-Akt (pAkt) was decreased in the control group., Conclusions: These results suggest that 19-peptide inhibits the growth and metastases of poorly differentiated gastric carcinoma cells, primarily by inducing apoptosis. The apoptotic mechanism could be related to anoikis and the PTEN/Akt pathway.

Small cell carcinoma of the stomach is a rare neoplasm. We report the barium meal and computed tomography findings of a 70-year-old man who presented with a long history of postprandial abdominal pain.