Objective To study the interaction and mechanism of prostaglandin I2 (PGI2) receptor/thromboxane A2 (TxA2) receptor (IP/TP) and cyclooxygenase-2 (COX-2) in ischemia reperfusion injury after liver transplantation of rat. Methods Rats were randomly divided into three groups: control group （n=16), orthotropic liver transplantation group （n=32) and nimesulide intervention group （n=32). The samples were obtained at 3 h, 6 h, 12 h and 24 h after operation. The expressions of COX-2, IP and TP mRNA were detected by RT-PCR. Immunohistochemistry was used to detect the localization and expression of COX-2. Hematoxylin Eosin staining was used to classify the injury extent of liver. Serum ALT and AST levels were detected to evaluate the changes of liver enzyme. Results COX-2 protein expression detected by immunohistochemistry in orthotropic liver transplantation group mainly distributed in the district of liver sinusoidal endothelial cells, liver cells and macrophage cells, which was significantly higher than control group and nimesulide intervention group. Expressions of IP mRNA, TP mRNA and COX-2 mRNA in the orthotropic liver transplantation group were significantly increased than those in control group (P＜0.05), and the ratio of IP/TP increased (P＜0.05). Expressions of IP mRNA and TP mRNA in nimesulide intervention group were significantly lower than that in the orthotropic liver transplantation group at 6 h and 12 h after operation (P＜0.05), and the ratio of IP/TP decreased at 3 h, 6 h and 24 h after operation (P＜0.05). The expression of COX-2 mRNA in nimesulide intervention group was significantly lower than that in the orthotropic liver transplantation group at 6 h, 12 h and 24 h after operation. In orthotropic liver transplantation group liver injury was obvious by HE staining, and more severve than that in nimesulide intervention group. Serum AST (each time) and ALT (3 h, 6 h and 12 h) levels in the orthotropic liver transplantation group were significantly higher than that in control group and nimesulide intervention group (P＜0.05) and peaked at 6 h after operation. Conclusion The balance of IP/TP takes part in and plays an important role in the ischemia reperfusion injury of liver transplantation. Changing imbalance of IP/TP may reduce liver transplantation ischemia reperfusion injury by inhibiting COX-2 expression.
Objective To investigate the relationship of p53 codon 72 polymorphism and susceptibility to gastric cancer in high incidence area of Hexi area of Gansu province. Methods The Arg/Pro polymorphism of p53 gene was detected by real-time PCR in 140 patients with gastric cancer, 110 patients with gastric precancerous lesion and 125 healthy controls; Helicobacter pylori (Hp) infection was detected by Warthin-Starry silver method． Results The Pro allele frequencies of p53 gene in gastric cancer cases (0.543) were higher than those in gastric precancerous lesion (0.482) and controls (0.472). The Pro genotype had a more than 1.846 fold increased risk of gastric cancer 〔OR=1.846; 95% 〗CI (1.006-3.387); P =0.046〕． With statistical analysis， the genotype of p53 gene was correlated with location and Laurens histological type （ P ＜ 0.05）. A significantly higher risk of gastric cancer was also seen in cases with p53 Pro genotype, food, Hp infection, positive mind factor and positive family history． Conclusion There is a b correlation between the p53 gene codon 72 Arg/Pro polymophism and susceptibility to gastric cancer in Hexi area of Gansu province and the Pro/Pro genotype may be one of the major risk factors in patients with gastric cancer.
ObjectiveTo explore the effect of DDX46 silencing on growth and apoptosis in esophageal squamous cell carcinoma cell TE-1 by the shRNA. MethodsThe relative expression of DDX46 mRNA in TE-1 cells was detected by real-time quantitative polymerase chain reaction (qRT-PCR) and compared with immortalized human esophageal squamous cell Het-1A. DDX46 shRNA-expressing lentivirus was applied to silence DDX46 (experimental group), and non-silencing control lentivirus was added (control group) with a multiplicity of infection of 5 in TE-1 cells. In both groups, cell growth was monitored using high content screening, cell colony-forming capacity was measured by colony formation assay, cell apoptosis were determined by flow cytometry. Further, the Stress and Apoptosis Signaling Antibody Array Kit was used to detect the changes of signaling molecules in TE-1 cells after DDX46 knockdown. ResultsCompared with the control group, cell counting after DDX46 silencing showed that TE-1 cell growth was significantly inhibited (P<0.001). Colony formation assay showed that cell colony-forming capacity was significantly inhibited (P<0.01). Annexin V-APC flow cytometry showed a significant increase in apoptosis (P<0.001). In PathScan® Antibody Array, the expression levels of Akt (Ser473, phosphorylation) and IκBα (Total, N/A) significantly decreased (P<0.01), and the expression of Caspase-3 (Asp175, cleaved) increased (P<0.05). ConclusionDDX46 is overexpressed in TE-1 cells. Targeted gene silencing of DDX46 inhibits cell growth, and induces cell apoptosis. DDX46 silencing probably by negative regulation of Akt/NF-κB signaling pathway, to play a role in inhibiting TE-1 cells growth and inducing apoptosis.