Hypoxia-mediated pancreatic beta cell death is one of the main causes of pancreatic beta celldeath, which leads to the loss of functional pancreatic beta cell mass and type 1 diabetes andtype 2 diabetes.However, the molecular mechanisms that control life and death of pancreatic beta cells remain poorly understood. Here we showed that mitochondrial fission was strongly induced in pancreatic beta cellsmainly due to an elevation of DRP1S616 phosphorylation through HIF-1αactivation and subsequent DRP1 mitochondrial translocation. Hypoxia-induced pancreatic beta cell death can be reversed by the inhibition of mitochondrial fission viaDRP1 knockdown. We further demonstrated that hypoxia-induced mitochondrial fission untightened the cristae formation, which subsequently triggers mitochondrial cytochrome c release and consequent caspase activation. Moreover, treatment with mitochondrial division inhibitor-1 (Mdivi-1), a specific inhibitor of DRP1-mediated mitochondrial fission, significantly suppressedbeta cell death in vitro, indicating a promising therapeutic strategy for treatment of diabetes.Taken together, our results reveal a crucial role for the DRP1-mediated mitochondrial fission in hypoxia-induced beta cell death, which provides a strong evidence for thisprocess as drug target indiabetestreatment.

ObjectiveTo analyze the clinical epidemiological characteristics of patients with gallbladder carcinoma recruited from 17 hospitals in five northwestern provinces of China (Shaanxi Province, Gansu Province, Qinghai Province, Ningxia Hui Autonomous Region, and Xinjiang Uygur Autonomous Region) from 2009 to 2013, and to summarize the clinical diagnosis and treatment data of gallbladder carcinoma.MethodsClinical information of 2379 patients with gallbladder carcinoma from 17 hospitals in five northwestern provinces of China was retrospectively collected and analyzed using the “Questionnaire for Gallbladder Carcinoma Patients in Northwestern Area of China.” All information was verified with EpiData software and analyzed with SPSS 13.0 software.Results(1) Gallbladder carcinoma accounted for 2.7% (2379/86,609) of all biliary tract diseases during the study period, which was significantly higher than that from 1986 to 1998 (P < 0.001). (2) Gallbladder carcinoma was more prone to occur in elderly women. The male:female incidence ratio was 1.0:2.1, the average age of onset of disease was 63.7 ± 11.3 years, and the incidence was higher in farmers than in other occupational groups. (3) A total of 57.2% (1360/2379) of patients with gallbladder carcinoma also had gallstones. (4) Abdominal pain (1796/2379, 75.5%) and jaundice (727/2379, 30.6%) were the most common clinical manifestations, 81.2% (1527/1881) were positive in those receiving B ultrasound examinations and 90.7% (1567/1727) were positive in those undergoing computed tomography, and 64.5% (1124/1742) of patients with gallbladder carcinoma were positive for carbohydrate antigen (CA) 19-9. (5) The pathological type of gallbladder carcinoma was mainly moderately and poorly differentiated adenocarcinoma with a high degree of malignancy. At admission, 55.1% (1091/1981) of patients had stage IV cancer among patients with TNM staging information; 55.9% (1331/2379) had lymphatic metastasis, 29.7% (706/2379) had bile duct metastasis, and 53.1% (1263/2379) had liver metastasis. (6) A total of 283 patients (283/2379, 11.9%) had incidentally detected gallbladder carcinoma. (7) The rate of radical surgical resection was 30.4% (723/2379).ConclusionThe proportion of gallbladder carcinoma in biliary tract diseases in the northwestern area of China was significantly higher from 2009 to 2013 than from 1986 to 1998. Gallbladder carcinoma was common in older women and mainly diagnosed at an advanced stage. Compared with other surveys in different regions, the rate of metastasis in this survey was high, leading to a low resection rate. Populations at high risk should undergo B-ultrasound examinations at regular follow-up intervals to increase the rate of early diagnosis of gallbladder carcinoma.

A disintegrin and metalloprotease-9 is over-expressed in hepatocellular carcinoma tissues, consistent with findings in other tumor entities, and is an independent prognostic marker of overall survival following hepatectomy. Further studies are needed to investigate the precise function of a disintegrin and metalloprotease-9 in the progression of hepatocellular carcinoma.

Liver regeneration is a complex process that is orchestrated by the precise interplay of cell proliferation, differentiation control, and molecular pathways, but this complicated molecular signaling network is not fully understood. In this study, we showed that N-Myc downstream-regulated gene 2 (NDRG2) is involved in this process. The mRNA and protein levels of NDRG2 were strongly reduced when liver regeneration reached a peak of activity. In addition, we found that rat NDRG2 expression and C-Myc expression were inversely correlated during this process. A low level of NDRG2 was observed as the C-Myc expression increased during regeneration. Moreover, a dramatic cell cycle arrest was found in normal rat liver-derived BRL cells 48 hours after being infected by adenoviral vectors expressing rat NDRG2. Meanwhile, the apoptotic rates were increased from 9.4% in control group to 64.7% in adenoviral vectors expressing rat NDRG2 group. These phenomena could also be observed in BRL 3A and L-02 cells. Further analysis revealed that NDRG2 overexpression may mediate the antiproliferative effect by inducing p53 and p21 regulated Bax/Bcl-2 increase and cyclin E-Cdk2 inhibition. In conclusion, our findings point to physiological roles for NDRG2 in liver regeneration.