Increased 5-hydroxymethylcytosine is a favorable prognostic factor of Helicobacter pylori-negative gastric cancer patients.

BACKGROUND: Most gastric cancer (GC) patients are diagnosed at middle or late stage because the symptoms in early stage are obscure, which causes higher mortality rates of GC. Helicobacter pylori (H. pylori) was identified as a class I carcinogen and leads to aberrant DNA methylation/hydroxymethylation. 5-hydroxymethylcytosine (5-hmC) plays complex roles in gene regulation of tumorigenesis and can be considered as an activating epigenetic mark of hydroxymethylation. AIM: To explore the association between 5-hmC levels and the progression and prognosis of GC patients with or without H. pylori infection. METHODS: A retrospective cohort study was conducted to estimate the predicted value of 5-hmC level in the progression and prognosis of GC patients with different H. pylori infection status. A total of 144 GC patients were recruited. RESULTS: The levels of 5-hmC were significantly decreased in tumor tissues (0.076 ± 0.048) compared with the matched control tissues (0.110 ± 0.057, P = 0.001). A high level of 5-hmC was an independent significant favorable predictor of overall survival in GC patients (hazard ratio = 0.61, 95% confidence interval: 0.38-0.98, P = 0.040), the H. pylori-negative GC subgroup (hazard ratio = 0.30, 95% confidence interval: 0.13-0.68, P = 0.004) and the GC patients with TNM stage Ⅰ or Ⅱ (hazard ratio = 0.32, 95% confidence interval: 0.13-0.77, P = 0.011). CONCLUSION: Increased 5-hmC is a favorable prognostic factor in GC, especially for H. pylori-negative subgroups.

Efficacy of HSV-tk/GCV system on human laryngeal squamous cell cancer in vitro / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>Efficacy of HSV-tk/GCV system antitumor effects was assessed on human laryngeal cancer cell line Hep-2 in vitro. To assess the HSV-tk/CGV system whether has an antitumour effect on human laryngeal squamous cell cancer Hep-2 in vitro. The mechanisms of cytotoxity were also assessed.</p><p><b>METHODS</b>Hep-2 cells were transfected with HSV-tk gene by lipofection. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the HSV-tk gene expression. MTT was utilized to test for the cytotoxicity of this system. The cell-circle arrest and apoptosis were analyzed by flowcytometry assay.</p><p><b>RESULTS</b>HSV-tk gene transfected cells demonstrated obvious cytoreductivity followed by ganciclovir (GCV) administration and this cytoreductivity showed partial GCV dose-independent. HSV-tk gene transfected cells demonstrated obvious s-phase arrest, no apoptosis and necrosis occurred.</p><p><b>CONCLUSIONS</b>The HSV-tk/GCV system can inhabit the growth of Hep-2 cells effectively. S-phase arrest perhaps is the main reason that leads to the cell inhibition in our study. HSV-tk/GCV system has potential antitumor effects for the future clinical practice.</p>

Effect of icariin on hypoxia induced vascular endothelial cells injury / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study the effect of icariin on vascular endothelial cells (VECs) injury induced by hypoxia.</p><p><b>METHODS</b>The hypoxia-ischemia model was established. The effect of icariin on injury of VECs activity induced by hypoxia was determined by MTT assay. The levels of malondialdehyde (MDA), superoxide dismutase (SOD) and lactate dehydrogenase (LDH) activity in cell homogenate were measured with corresponding kit. Effect of icariin on cells apoptosis induced by hypoxia was determined by Hoechst 33342 fluorescent staining, cell ultrastructure observation under transmission electron microscopy and analysis on gene fragmentation by flow cytometry and DNA gel electrophoresis.</p><p><b>RESULTS</b>ICA could inhibit the hypoxia induced VECs reduction, suppress LDH activity, reduce the MDA production, and enhance SOD activity under hypoxia. Hypoxia could induce VECs apoptosis, revealed chromation condensed in nuclei with the fragments arranged along the nuclear membrane. DNA gel electrophoresis showed typical ladder strands of DNA. Cells displayed a typical sub-diploid peak in flow cytometry. ICA could significantly inhibit the hypoxia induced apoptosis of VECs.</p><p><b>CONCLUSION</b>ICA has the protective effect on hypoxia injured VECs, which may be related to its effect of anti-apoptosis, anti-lipid peroxidation and SOD activity enhancing.</p>

[Study of alginate/chitosan microcapsules for immobilization of Escherichia coli DH5 alpha].

Objective proteins synthesized from genetically recombined Escherichia coli strain (E. coli) have been successfully produced by microbe fermentation, but complicated separation and purification steps always make against the maintenance of activities as well as increase the cost. Aiming at simplifying the process, an idea of administrating directly the microencapsulated genetically recombined E. coli is proposed. In this paper, study on culture of E. coli DH5 alpha immobilized in alginate/chitosan (ACA) microcapsule is presented. It was found that E. coli DH5 alpha grew well in the microcapsule with stable growth period longer than that of suspension culture, and cell aggregation phenomenon was observed. In vivo experiments showed that ACA microcapsules with E. coli DH5 alpha stayed over 48 h in mouse intestine, and the morphology of microcapsules was kept intact. These preliminary results have demonstrated that administration of microencapsulated E. coli DH5 alpha is safe, which laied the foundation for microencapsulated genetically recombined E. coli as carriers of gene engineering drugs.