Gene therapy in cancer

Gene therapy, recently frequently investigated, is an alternative treatment method that introduces therapeutic genes into a cancer cell or tissue to cause cell death or slow down the growth of the cancer. This treatment has various strategies such as therapeutic gene activation or silencing of unwanted or defective genes; therefore a wide variety of genes and viral or nonviral vectors are being used in studies. Gene therapy strategies in cancer can be classified as inhibition of oncogene activation, activation of tumor suppressor gene, immunotherapy, suicide gene therapy and antiangiogenic gene therapy. In this review, we explain gene therapy, gene therapy strategies in cancer, approved gene medicines for cancer treatment and future of gene therapy in cancer. Today gene therapy has not yet reached the level of replacing conventional therapies. However, with a better understanding of the mechanism of cancer to determine the right treatment and target, in the future gene therapy, used as monotherapy or in combination with another existing treatment options, is likely to be used as a new medical procedure that will make cancer a controllable disease.     

Experimental adhesion model: effect of viscosities of fluids put in the peritoneal cavity on preventing peritoneal adhesions.

In this study we assessed the effectiveness of fluid viscosities placed in the peritoneal cavity to prevent postoperative peritoneal adhesions. Thirty-six Wistar albino female rats (average weight: 160 +/- 30 g, average age: 6.5 months) were divided into three groups of equal number. A standard adhesion pattern was formed in each group. Then, 3 ml isotonic sodium chloride solution (relative viscosity value: 1) was added into the peritoneal cavity of group 1; 3 ml standard 6% hydroxy ethyl starch solution (HES) (relative viscosity value: 2.9) was added into the peritoneal cavity of group 2; and a standard HES solution that was concentrated by dehydration (relative viscosity value: 249.7) was added into the peritoneal cavity of group 3. All rats were sacrificed on postoperative day 10 and the adhesions that formed were graded. In group 1, grade-3 adhesions developed in 9 (75%) rats, and grade-2 developed in 3 (25%) rats. In group 2, grade-3 adhesions developed in 1 (8.3%) rat, grade-2 developed in 6 (50%) rats, and grade-1 developed in 5 (41.6%) rats; in group 3, grade-3 adhesions developed in 9 (75%) rats, and grade-2 developed in 3 (25%) rats. The adhesion scores of group 3 and group 1 were equal to each other (P=1), while the adhesion score of group 2 was significantly less (chi(2): 18.23, P<0.001). Increasing the viscosity of fluids that are inserted in the peritoneal cavity may reduce the formation of postoperative peritoneal adhesions till a critical value of unknown viscosity is achieved. The mechanism behind this process remains unclear.     

Partitioning, diffusion, and ligand binding of raft lipid analogs in model and cellular plasma membranes

Several simplified membrane models featuring coexisting liquid disordered (Ld) and ordered (Lo) lipid phases have been developed to mimic the heterogeneous organization of cellular membranes, and thus, aid our understanding of the nature and functional role of ordered lipid-protein nanodomains, termed "rafts". In spite of their greatly reduced complexity, quantitative characterization of local lipid environments using model membranes is not trivial, and the parallels that can be drawn to cellular membranes are not always evident. Similarly, various fluorescently labeled lipid analogs have been used to study membrane organization and function in vitro, although the biological activity of these probes in relation to their native counterparts often remains uncharacterized. This is particularly true for raft-preferring lipids ("raft lipids", e.g. sphingolipids and sterols), whose domain preference is a strict function of their molecular architecture, and is thus susceptible to disruption by fluorescence labeling. Here, we analyze the phase partitioning of a multitude of fluorescent raft lipid analogs in synthetic Giant Unilamellar Vesicles (GUVs) and cell-derived Giant Plasma Membrane Vesicles (GPMVs). We observe complex partitioning behavior dependent on label size, polarity, charge and position, lipid headgroup, and membrane composition. Several of the raft lipid analogs partitioned into the ordered phase in GPMVs, in contrast to fully synthetic GUVs, in which most raft lipid analogs mis-partitioned to the disordered phase. This behavior correlates with the greatly enhanced order difference between coexisting phases in the synthetic system. In addition, not only partitioning, but also ligand binding of the lipids is perturbed upon labeling: while cholera toxin B binds unlabeled GM1 in the Lo phase, it binds fluorescently labeled GM1 exclusively in the Ld phase. Fluorescence correlation spectroscopy (FCS) by stimulated emission depletion (STED) nanoscopy on intact cellular plasma membranes consistently reveals a constant level of confined diffusion for raft lipid analogs that vary greatly in their partitioning behavior, suggesting different physicochemical bases for these phenomena.     

Clinical and laboratory aspects of a trichinellosis outbreak in Izmir, Turkey

Epidemiological, clinical and laboratory data were collected during an outbreak of trichinellosis, which occurred in Izmir, Turkey, between January and March 2004. The source of the infection was raw meatballs made with a mixture of uncooked beef and pork. Of 474 persons who were admitted at the Ataturk Training and Research Hospital during this period with a history of raw meatball consumption, the diagnosis of trichinellosis was confirmed for 154 (32.5%, 87 males and 67 females; mean age 31 years, range 6-67 years). Among persons with a confirmed diagnosis, 79% had myalgia, 77% weakness and malaise, 63% arthralgia, 40% jaw pain, 68% fever, 63% periorbital and/or facial oedema, 49% oedema at the trunk and limb, 42% abdominal pain, 40% nausea and vomiting, 28% diarrhoea, 23% subconjunctival haemorrhage, 25% macular or petechial rash, 4% subungual haemorrhage, 15% cardiac complaints and 0.2% neurological complaints. Nine patients (5.8%) were hospitalised due to severe myalgia (n = 2), high fever (n = 3), neurological manifestations (n = 1), thrombophlebitis (n = 2) and palmar erythema (n = 1). Eosinophilia was present in 88% of the confirmed cases at the admission. Elevated levels of serum creatine phosphokinase, lactic dehydrogenase and aspartate aminotransferase were detected in 72%, 70% and 16% of the confirmed cases, respectively. The seroconversion occurred in most of the infected people between the 4th and 6th weeks after the infection. All of the confirmed cases were treated with mebendazole. People with severe symptoms were treated also with prednisolone (60 mg/day for three days) and those with a moderately severe clinical pattern received a non-steroid anti-inflammatory drug (naproxen sodium, 550 mg/day). All confirmed cases recovered without any clinical sequela.     

Regulation of gene expression and biochemical changes in small intestine of newborn diabetic rats by exogenous ghrelin

The aim of this study was to investigate (i) the cholecystokinin, somatostatin and apelin mRNA levels, (ii) the changes in levels and localization of these peptides, (iii) relation between these peptides, (iv) antiapoptotic effects and (v) antioxidant effects of ghrelin. The rats were divided into four groups second day after birth. These groups were respectively treated with physiological saline, ghrelin (100μg/kg/day), streptozotocin (100mg/kg), ghrelin and streptozotocin. After four weeks, small intestine and blood samples were taken from rats. Cholecystokinin mRNA and peptide, somatostatin mRNA, release to duodenal lumen of apelin peptide and apelin mRNA signals decreased in ghrelin-treated diabetic rats compared to the diabetic group. There was no statistically significant difference among the four groups for somatostatin and apelin peptides. Caspase-3 signals were not observed only in diabetic group treated with ghrelin. Caspase-8 signals were increased while PCNA signals were decreased in diabetic group given ghrelin compared to diabetic group. Small intestine CAT, SOD, GP(x) and GST activities and GSH levels were decreased and LPO, PC levels were increased in diabetic rats. Administration of ghrelin to diabetic rats caused an increase in intestinal CAT, SOD, GP(x) and GST activities and GSH levels, while PC levels decreased. As a result, we observed positive changes in diabetic rats treated with ghrelin in both microscopic and biochemical studies. We can suggest that ghrelin may be an important hormone for the treatment of diabetes.     

Synthesis and analgesic activity of some acetamide derivatives

In the present study, some acetamide derivatives were synthesized and their potential analgesic activities were investigated. N-(benzothiazol-2-yl)-2-[(1-substituted-1H-tetrazol-5-yl)thio]acetamide derivatives were obtained by the nucleophilic substitution reaction of 2-chloro-N-(benzothiazole-2-yl)acetamides with appropriate tetrazol-5-thioles. The chemical structures of the compounds were elucidated by IR, 1H-NMR, 13C-NMR and FAB?-MS spectral data and elemental analyses. The prepared compounds were investigated for their potential analgesic properties against thermal, mechanical and chemical nociceptive stimuli using hot-plate, tail-clip and acetic acid-induced writhing tests, respectively. The assessment of motor coordination was carried out using Rota-Rod test. Tested compounds applied at 100 mg/kg doses caused significant decrease in acetic acid-induced writhing responses and increase in hot-plate and tail-clip latencies. None of the compounds exhibited destructive effect on motor coordination of the mice in Rota-Rod performance.     

miR-376b controls starvation and mTOR inhibition-related autophagy by targeting ATG4C and BECN1

Macroautophagy (autophagy) is the major intracellular degradation pathway for long-lived proteins and organelles. It helps the cell to survive a spectrum of stressful conditions including starvation, growth factor deprivation and misfolded protein accumulation. Moreover, abnormalities of autophagy play a role in major health problems including cancer and neurodegenerative diseases. Yet, mechanisms controlling autophagic activity are not fully understood. Here, we describe hsa-miR-376b (miR-376b) as a new microRNA (miRNA) regulating autophagy. We showed that miR-376b expression attenuated starvation- and rapamycin-induced autophagy in MCF-7 and Huh-7 cells. We discovered autophagy proteins ATG4C and BECN1 (Beclin 1) as cellular targets of miR-376b. Indeed, upon miRNA overexpression, both mRNA and protein levels of ATG4C and BECN1 were decreased. miR-376b target sequences were present in the 3' UTR of ATG4C and BECN1 mRNAs and introduction of mutations abolished their miR-376b responsiveness. Antagomir-mediated inactivation of the endogenous miR-376b led to an increase in ATG4C and BECN1 levels. Therefore, miR-376b controls autophagy by directly regulating intracellular levels of two key autophagy proteins, ATG4C and BECN1.