48 research outputs found
Herpes simplex virus 1 amplicon vector-mediated siRNA targeting epidermal growth factor receptor inhibits growth of human glioma cells in vivo
In primary glioblastomas and other tumor types, the epidermal growth factor receptor (EGFR) is frequently observed with alterations, such as amplification, structural rearrangements, or overexpression of the gene, suggesting an important role in glial tumorigenesis and progression. In this study, we investigated whether posttranscriptional gene silencing by vector-mediated RNAi to inhibit EGFR expression can reduce the growth of cultured human gli36 glioma cells. To "knock down" EGFR expression, we have created HSV-1-based amplicons that contain the RNA polymerase III-dependent H1 promoter to express double-stranded hairpin RNA directed against EGFR at two different locations (pHSVsiEGFR I and pHSVsiEGFR II). We demonstrate that both pHSVsiEGFR I and pHSVsiEGFR II mediated knock-down of transiently transfected full-length EGFR or endogenous EGFR in a dose-dependent manner. The knock-down of EGFR resulted in the growth inhibition of human glioblastoma (gli36-luc) cells both in culture and in athymic mice in vivo. Cell cycle analysis and annexin V staining revealed that siRNA-mediated suppression of EGFR induced apoptosis. Overall HSV-1 amplicons can mediate efficient and specific posttranscriptional gene silencing. Copyright © The American Society of Gene Therapy
Coupling of alpha(1)-Adrenoceptors to ERK1/2 in the Human Prostate
Introduction: alpha(1)-Adrenoceptors are considered critical for the regulation of prostatic smooth muscle tone. However, previous studies suggested further alpha(1)-adrenoceptor functions besides contraction. Here, we investigated whether alpha(1)-adrenoceptors in the human prostate may activate extracellular signal-regulated kinases (ERK1/2). Methods: Prostate tissues from patients undergoing radical prostatectomy were stimulated in vitro. Activation of ERK1/2 was assessed by Western blot analysis. Expression of ERK1/2 was studied by immunohistochemistry. The effect of ERK1/2 inhibition by U0126 on phenylephrine-induced contraction was studied in organ-bath experiments. Results: Stimulation of human prostate tissue with noradrenaline (30 mu M) or phenylephrine (10 mu M) resulted in ERK activation. This was reflected by increased levels of phosphorylated ERK1/2. Expression of ERK1/2 in the prostate was observed in smooth muscle cells. Incubation of prostate tissue with U0126 (30 mu M) resulted in ERK1/2 inhibition. Dose-dependent phenylephrine-induced contraction of prostate tissue was not modulated by U0126. Conclusions: alpha(1)-Adrenoceptors in the human prostate are coupled to ERK1/2. This may partially explain previous observations suggesting a role of alpha(1)-adrenoceptors in the regulation of prostate growth. Copyright (C) 2011 S. Karger AG, Base
The tumourâstromal interaction between intratumoral c-Met and stromal hepatocyte growth factor associated with tumour growth and prognosis in non-small-cell lung cancer patients
Bowel preparation and peri-operative management for radical cystectomy in Turkey: Turkish Urooncology Association multicenter survey
PubMedID: 21656469Purpose: To investigate the preferences and practice patterns of urooncologic surgeons in Turkey on bowel preparation and peri-operative management for radical cystectomy. Materials and Methods: This study was conducted by Turkish Urooncology Association as a multicenter survey. Participants were asked to fill in questionnaires dispensed at annual oncologic meeting or using internet access to the website of Urooncology Association. The questionnaire consisted of multiple choice or open-ended questions related to frequency of cystectomy, surgical technique and type of diversion, bowel preparation protocol, nasogastric tube applications, antibiotic prophylaxis, and deep vein thrombosis prophylaxis. Collected data from the survey were presented descriptively. Results: Forty-four questionnaires from 44 surgeons of different centers were evaluated. All participants answered that they always perform bowel preparation before cystectomy. Four participants reported that they had an experience of cystectomy without bowel preparation. Bowel preparation methods included long conservative methods, short enema protocols, and Golytely, but there were significant differences in application of each method. Of participants, 88.6% perform diversion by themselves whereas others ask help from a general surgeon. Antibiotic prophylaxis is preferred mostly by 2 agents using third-generation cephalosporins and metronidazole for a period of 5 days or more in the majority. Type, duration, and dosage of deep vein thrombosis prophylaxis differed among participants.Conclusion: There are significant individual differences in peri-operative management of radical cystectomy, which render deficient and sometimes inadequate patient care. There is a need to establish standard protocols for bowel preparation and adequate peri-operative management for radical cystectomy
Prokineticin receptor-1 is a new regulator of endothelial insulin uptake and capillary formation to control insulin sensitivity and cardiovascular and kidney functions
International audienceBACKGROUND: Reciprocal relationships between endothelial dysfunction and insulin resistance result in a vicious cycle of cardiovascular, renal, and metabolic disorders. The mechanisms underlying these impairments are unclear. The peptide hormones prokineticins exert their angiogenic function via prokineticin receptor-1 (PKR1). We explored the extent to which endothelial PKR1 contributes to expansion of capillary network and the transcapillary passage of insulin into the heart, kidney, and adipose tissues, regulating organ functions and metabolism in a specific mice model. METHODS AND RESULTS: By combining cellular studies and studies in endothelium-specific loss-of-function mouse model (ec-PKR1-/-), we showed that a genetically induced PKR1 loss in the endothelial cells causes the impaired capillary formation and transendothelial insulin delivery, leading to insulin resistance and cardiovascular and renal disorders. Impaired insulin delivery in endothelial cells accompanied with defective expression and activation of endothelial nitric oxide synthase in the ec-PKR1-/- aorta, consequently diminishing endothelium-dependent relaxation. Despite having a lean body phenotype, ec-PKR1-/- mice exhibited polyphagia, polydipsia, polyurinemia, and hyperinsulinemia, which are reminiscent of human lipodystrophy. High plasma free fatty acid levels and low leptin levels further contribute to the development of insulin resistance at the later age. Peripheral insulin resistance and ectopic lipid accumulation in mutant skeletal muscle, heart, and kidneys were accompanied by impaired insulin-mediated Akt signaling in these organs. The ec-PKR1-/- mice displayed myocardial fibrosis, low levels of capillary formation, and high rates of apoptosis, leading to diastolic dysfunction. Compact fibrotic glomeruli and high levels of phosphate excretion were found in mutant kidneys. PKR1 restoration in ec-PKR1-/- mice reversed the decrease in capillary recruitment and insulin uptake and improved heart and kidney function and insulin resistance. CONCLUSIONS: We show a novel role for endothelial PKR1 signaling in cardiac, renal, and metabolic functions by regulating transendothelial insulin uptake and endothelial cell proliferation. Targeting endothelial PKR1 may serve as a therapeutic strategy for ameliorating these disorders.</p