转基因疾病的制造将可能产生灾难

每过一些年,欧洲家鼠便会在澳大利亚农区大量暴发.道路上挤满了老鼠,价值数百万美元的谷物被吃光或是糟蹋掉,房屋和建筑也难逃脱此劫.唯一的防备办法就是投放毒药,对于老鼠来说,这会缓慢的将其折磨致死,但同时这种带毒的诱饵也能吸引许多其它动物.

Transcription factor Sp1 expression in gastric cancer and its relationship to long-term prognosis

AIM:To explore the expression of Sp1 in gastric carcinoma as well as its association with other clinicopathologic features, and to evaluate the role of Spl as a prognostic indicator of gastric carcinoma. METHODS: By using immunohistochemistry, we examined the Spl expression patterns in 65 cases of human gastric cancer, and 40 normal gastric mucosa specimens. Simultaneously, the correlation between Spl expression and clinical outcome or clinicopathologic features was investigated. RESULTS: The percentage of Spl expression was 12.5% (5/40) in normal gastric mucosa, and the Spl protein was mainly expressed in the nuclei of cells located in the mucous neck region. In sharp contrast, strong Spl expression was detected in tumor cells, whereas no or faint Spl staining was detected in stromal cells and normal glandular cells surrounding the tumors. The expression rate of Spl in gastric cancer lesions was 53.85% (35/65). The medium survival duration in patients who had a tumor with negative, weak and strong Spl expressions was 1 700, 1 560 and 1 026 d, respectively (P<0.05). Spl protein expression was closely related to the depth of tumor infiltration (X2 = 13.223, P<0.01) and TNM stage (X2= 11.009, P<0.05), but had no relationship with the number of lymph nodes and Lauren's classification (P>0.05). Cox regression model for multivariate analysis revealed that high Spl expression (P<0.05) and advanced stage (P<0.01) were independent predictors of poor survival. CONCLUSION: Normal and malignant gastric tissues have unique Spl expression patterns. Spl might serve as an independent prognostic factor, by influencing the tumor infiltration and progression.

INHIBITORY ROLE OF TRANSCRIPTION FACTOR COUP-TFII IN EXPRESSION OF HTERT IN HELA CELLS

To clone and identify the proteins involved in regulating the transcription of hTERT and study the role of genes in both hTERT transcription and telomerase activity. Methods The full cDNA of COUP-TFII was cloned from HeLa cDNA library by hTERT promoter-based yeast one-hybrid assay and then in-frame inserted into His-tag fusion expression vector pEK318. The His-tag COUP-TFII fusion proteins were purified by Ni-NTA chromatography. The interaction of COUP-TFII with hTERT promoter in vitro was identified by electrophoretic mobility shift assay and Footprint. The role of COUP-TFII in both hTERT transcription and telomerase activity were probed through Luciferase reporter assay, Northern blot, and TRAP-PCR ELISA. Results COUP-TFII could firmly bind to the downstream E-box and the other two binding sites in hTERT promoter. Luciferase reporter assay indicated COUP-TFII could suppress hTERT promoter activity and stable introduction of COUP-TFII into HeLa cells also decreased both endogenous hTERT transcription and telomerase activity. Conclusion The human COUP-TFII can firmly bind to hTERT promoter, and inhibit telomerase activity through decreasing hTERT transcription. It will greatly facilitate understanding of telomerase regulation in normal and cancer cells

Genetically modified mouse models for the study of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease(NAFLD) is associated with obesity,insulin resistance,and type 2 diabetes.NAFLD represents a large spectrum of diseases ranging from(1) fatty liver(hepatic steatosis);(2) steatosis with inflammation and necrosis;to(3) cirrhosis.The animal models to study NAFLD/nonalcoholic steatohepatitis(NASH) are extremely useful,as there are still many events to be elucidated in the pathology of NASH.The study of the established animal models has provided many clues in the pathogenesis of steatosis and steatohepatitis,but these remain incompletely understood.The different mouse models can be classified in two large groups.The first one includes genetically modified(transgenic or knockout) mice that spontaneously develop liver disease,and the second one includes mice that acquire the disease after dietary or pharmacological manipulation.Although the molecular mechanism leading to the development of hepatic steatosis in the pathogenesis of NAFLD is complex,genetically modified animal models may be a key for the treatment of NAFLD.Ideal animal models for NASH should closely resemble the pathological characteristics observed in humans.To date,no single animal model has encompassed the full spectrum of human disease progression,but they can imitate particular characteristics of human disease.Therefore,it is important that the researchers choose the appropriate animal model.This review discusses various genetically modified animal models developed and used in research on NAFLD.

Insights into restrictive cardiomyopathy from clinical and animal studies

Cardiomyopathies are diseases that primarily affect the myocardium, leading to serious cardiac dysfunction and heart failure. Out of the three major categories of cardiomyopathies （hypertrophic, dilated and restrictive）, restrictive cardiomyopathy （RCM） is less common and also the least studied. However, the prognosis for RCM is poor as some patients dying in their childhood. The molecular mechanisms behind the disease development and progression are not very clear and the treatment of RCM is very difficult and often ineffective. In this article, we reviewed the recent progress in RCM research from the clinical studies and the translational studies done on diseased transgenic animal models. This will help for a better understanding of the mechanisms underlying the etiology and development of RCM and for the design of better treatments for the disease.

Overexpression of fibrinogen-like protein 2 protects against T cell-induced colitis

AIMTo determine the effect of overexpression of fibrinogen-like protein 2 (FGL2) on regulatory T cell (Treg) and effector T (Teff) cell function on T cell-induced colitis in Rag1-/- mice.METHODSTreg and Teff cells from fgl2-/-, fgl2+/+, and fgl2Tg mice were purified by FACS. They were studied in vitro for immunosuppressive activity and cell proliferation and in vivo for their effects on the development and prevention of T cell-induced colitis in Rag1-/- mice.RESULTSIn vitro, fgl2Tg Treg had enhanced immunosuppressive activity, and fgl2Tg Teff had reduced proliferation to alloantigen stimulation. Transfer of Teff from C57Bl/6J mice (fgl2+/+) into Rag1-/- mice produced both clinical and histologic colitis with dense infiltrates of CD3+ T cells, crypt abscesses and loss of goblet cells. Fgl2Tg Treg prevented the development of T cell-induced colitis, whereas fgl2+/+ and fgl2-/- Treg were only partially protective. In mice that received fgl2Tg Treg, the ratio of Foxp3+ to CD3+ cells was increased both in the colon and in mesenteric lymph nodes, and Teff cell proliferation as determined by staining with Ki67 was reduced. Teff cells from fgl2Tg mice did not produce colitis.CONCLUSIONHere we show that fgl2Tg Teff are hypoproliferative and do not induce colitis. We further demonstrate that fgl2Tg Treg prevent colitis in contrast to fgl2+/+ Treg, which were only partially protective. These studies collectively provide a rationale for exploring the use of FGL2 or Treg expressing high levels of FGL2 in the treatment of inflammatory bowel disease.

Translational Benefits of Gene Therapy to Date

Gene therapy is now a reality with a number of early phase clinical trials having been completed and several currently in progress. In spite of some early setbacks substantial progress has been made with treatment of several different diseases using a variety of delivery vectors and transgenes. Indeed for some diseases gene therapy is now the treatment of choice, in particular the inherited immune deficiencies. Treatment of ocular diseases and cancer are also showing great promise. Immune responses and insertional mutagenesis still pose problems but refinement of delivery systems and an increased understanding of oncogene activation should ensure that more successful protocols will emerge in the near future. Continuous progress suggests that a wider range of diseases can be treated with gene therapy in the future.