Knockdown of ZNF479 inhibits proliferation and glycolysis of gastric cancer cells through regulating ß-catenin/c-Myc signaling pathway.

Gastric cancer is the fifth most common malignancy and the third most deadly tumor in the world. Zinc finger protein 479 (ZNF479) has been demonstrated to play crucial roles in hepatocellular carcinoma. However, the function of ZNF479 in gastric cancer remains to be clarified. The current study aimed to investigate the role of ZNF479 in gastric cancer progression and elucidate the potential molecular mechanism. In this study, Cell Count Kit-8 and colony formation assays demonstrated that knockdown of ZNF479 inhibited cell proliferation in AGS and SGC-7901 cells. Of note, knockdown of ZNF479 hinders tumor growth of xenograft tumor mice. What is more, knockdown of ZNF479 inhibited glucose uptake, lactate production, adenosine triphosphate level, and extracellular acidification ratio; increased oxygen consumption ratio in gastric cancer cells; and decreased the expression of glycolytic proteins both in vitro and in vivo. Furthermore, analysis mechanism suggests that ZNF479 participated in the regulation of gastric cancer progression through affecting the ß-catenin/c-Myc signaling pathway. Collectively, ZNF479 plays a role as an oncogene through modulating ß-catenin/c-Myc signaling pathway in the development of gastric cancer, which provides a new research target for future studies.

Is Helicobacter pylori infection associated with glycemic control in diabetics?

AIM: To investigate whether Helicobacter pylori (H. pylori) infection is associated with glycemic control and whether hyperglycemia is modified by eradication therapy. METHODS: The databases of PubMed, Cochrane Library, Chinese BioMedicine Web Base and Chinese Science and Technology Journals were searched from inception to June 2014. Studies examining the association between H. pylori infection and glycemic control and/or the effect of eradication treatment on glycemic control in diabetic humans were eligible for inclusion. Meta-analyses were conducted using the Review Manager software version 5.2. The outcome measures are presented as weighed mean differences (WMDs) with 95% confidence intervals (CIs). Statistical heterogeneity was assessed by the Cochran Q test and the I(2) statistic. RESULTS: A total of 21 relevant publications were identified. A meta-analysis of 11 studies with 513 patients with diabetes mellitus (DM) showed significantly lower glycosylated hemoglobin (HbA1c) levels in the H. pylori-negative than H. pylori-positive DM participants (WMD = 0.43, 95%CI: 0.07-0.79; P = 0.02). In children and adolescents with type 1 DM (T1DM), there was a positive association between H. pylori infection and HbA1c level (WMD = 0.35, 95%CI: 0.05-0.64; P = 0.02), but there was no difference in those with type 2 DM (T2DM, WMD = 0.51, 95%CI: -0.63-1.65; P = 0.38). A meta-analysis of six studies with 325 T2DM participants showed a significant difference in the fasting plasma glucose levels between H. pylori-positive and H. pylori-negative participants (WMD = 1.20, 95%CI: 0.17-2.23; P = 0.02). Eradication of H. pylori did not improve glycemic control in the T2DM participants in a three-month follow-up period (HbA1c decrease: WMD = -0.03, 95%CI = -0.14-0.08; P = 0.57; fasting plasma glucose decrease: WMD = -0.06, 95%CI: -0.36-0.23; P = 0.68). Glycemic control was significantly better in T1DM participants who were not reinfected than in those who were reinfected (HbA1c: WMD = 0.72, 95%CI: 0.32-1.13: P = 0.00). CONCLUSION: H. pylori infection is associated with poorer glycemic control in T1DM patients, but eradication may not improve glycemic control in DM in a short-term follow-up period.

Lipotoxic effect of p21 on free fatty acid-induced steatosis in L02 cells.

Nonalcoholic fatty liver disease (NAFLD) is increasingly regarded as a hepatic manifestation of metabolic syndrome. Though with high prevalence, the mechanism is poorly understood. This study aimed to investigate the effects of p21 on free fatty acid (FFA)-induced steatosis in L02 cells. We therefore analyzed the L02 cells with MG132 and siRNA treatment for different expression of p21 related to lipid accumulation and lipotoxicity. Cellular total lipid was stained by Oil Red O, while triglyceride content, cytotoxicity assays, lipid peroxidation markers and anti-oxidation levels were measured by enzymatic kits. Treatment with 1 mM FFA for 48 hr induced magnificent intracellular lipid accumulation and increased oxidative stress in p21 overload L02 cells compared to that in p21 knockdown L02 cells. By increasing oxidative stress and peroxidation, p21 accelerates FFA-induced lipotoxic effect in L02 cells and might provide information about potentially new targets for drug development and treatments of NAFLD.