Coralli C et al. The seedlings were grown for a further 8-d period by placing the plates in the growth chamber in a completely randomized design. Author contributions: J.C.-G. and J.L.-B. Limitations of the reporter green fluorescent protein under simulated tumor conditions Cancer Res 2001 61: 4784–4790. Evaluation of a new dual-specificity promoter for selective induction of apoptosis in breast cancer cells Cancer Gene Ther 2001 8: 298–307, Modlich U, Pugh CW, Bicknell R . When the PGK110/E9 combination was tested after hypoxic irradiation, the presence of the extra five HREs did not change induction levels in MCF-7 cells, but caused a reduction in response in T24 cells. We do not capture any email address. Thank you for your interest in spreading the word on PNAS. You are using a browser version with limited support for CSS. Finally, for the construct containing 10 PGK1 HRE units plus E9 (pPGK110E9), two five-unit ODNs, 5’- GATC(TGTCACGTCCTGCACGAC)5-3’ and 5’-GATC(GTCGTGCAGGACGTGACA)5-3’, were cloned in one ligation reaction, adjacently and immediately upstream of E9. Three different HREs were tested, from the human erythropoietin (Epo) gene, the murine phosphoglycerate kinase 1 (PGK1) gene, and a novel sequence based on the human vascular endothelial growth factor HRE (nVEGF). Normal p53 status and function despite the development of drug resistance in human breast cancer cells Cell Growth Differ 1995 6: 1395–1403, Kawasaki T et al. designed research; R.O.-C., C.D.-P., R.E.d.R., J.C.-G., and J.L.-B.
All sample manipulations were carried out in an anaerobic glove cabinet (Don Whitley Scientific, Shipley, UK) at 37°C under 5% CO2, 5% H2 and 90% N2, in the presence of a palladium catalyst. HRP activity was analyzed as described previously.12. The level of hypoxia- and/or radiation-induced EGFP expression was expressed as the percentage of EGFP-expressing cells in the treated sample, compared with the corresponding oxic/sham-irradiated sample transfected with the same plasmid. The combination of hypoxia-regulatory elements (HREs) from the Epo gene and radiation-responsive CArG elements was found to induce the most selective and robust transgene expression under the separate or combined stimuli, and to effectively control a novel GDEPT system. Sensitivity of T24 cells to the prodrug indole-3-acetic acid (IAA). Reactive oxygen intermediates increase vascular endothelial growth factor expression in vitro and in vivo J Clin Invest 1996 98: 1667–1675, Chua CC, Hamdy RC, Chua BH . These enhancers were produced from single-stranded oligo-deoxyribonucleotides (ODNs), and subsequently cloned by the method described in Marples et al.15 The enhanced green fluorescent protein (EGFP) coding sequence (CDS) was excised from pEGFP-N1 (Clontech) by EcoRI/NotI digestion, and the resulting fragment inserted into each vector linearized with the same restriction enzymes Figure 1. Other chimeric promoters based on the CMV basal gene promoter have shown robust hypoxic35 and radiation1516 inducibility. Correspondence to PubMed Central The results presented here demonstrate, for the first time, robust and tight regulation of gene expression via HRE/CArG chimeric promoters. This observation has been independently confirmed in a range of other cell lines (N Chadderton and S Robinson, personal communication). The five-unit nVEGF enhancer in pnVEGFE9 was cloned in a single step from two complementary ODNs: 5’-GATC(TTGATACGTGCTGCACGA)5-3’ and 5’-GATC(TCGTGCAGCACGTATCAA)5-3’. In all cases, the activated synthetic promoters produced a surviving fraction comparable to that of CMV in air. performed research; M.M.-T., R.E.d.R., J.C.-G., and J.L.-B. Can gene therapy overcome the problem of hypoxia in radiotherapy? These elements are found at varying distances from, and orientations to, the coding region of several hypoxia-regulated genes (reviewed in Ref. When Amanda Strike’s children became teenagers, she decided life needed a shakeup. Significance tests were carried out on the data groups by using analysis of variance (ANOVA) followed by pair-wise comparison between specific groups (Student's t test). As previously observed in our group, at the oxygenation levels adopted in this study (0.1% O2) the fluorescence signal in EGFP-transfectants was not itself affected by hypoxic treatment.51. Cells were routinely tested and found free of mycoplasma infection (MycoTect kit, Life Technologies). Endothelial exposure to hypoxia induces Egr-1 expression involving PKCalpha-mediated Ras/Raf-1/ERK1/2 pathway J Cell Physiol 2001 188: 304–312, Yan SF et al. First, three HRE units were inserted upstream of E9, then a further two HRE units making a total of five in the final enhancer Figure 1. Combining gene therapy and radiotherapy protocols has the potential to overcome many of the limitations of adverse tumor biology on cancer treatment. Additionally, in order to further amplify suicide gene expression, a molecular switch, such as the one described in Scott et al16 could be utilized. The communication between bacteria and their hosts through interkingdom signaling is a recent field of research. We need a deliberative process that’s transparent, politically neutral, scientifically balanced, and representative of all relevant disciplines and expertise. The expression and distribution of the hypoxia-inducible factors HIF-1 alpha and HIF-2 alpha in normal human tissues, cancers, and tumor-associated macrophages Am J Pathol 2000 157: 411–421, Greco O, Patterson AV, Dachs GU . All chimeric promoters could be activated by hypoxia and/or IR-treatment, and selectively control marker gene expression in human T24 bladder carcinoma and MCF-7 mammary carcinoma cells. A marginal induction (1.3 ± 0.1) was detected in hypoxic MCF-7 cells Figure 2. T24 cells transfected with plasmid constructs containing the horseradish peroxidase (HRP) cDNA controlled by hypoxia- and/or radiation-responsive promoters were exposed to the activating stimuli of hypoxia, radiation or the combination of the two treatments. Since gene activation would be controlled, damage to surrounding normal tissue would be reduced, thereby improving the therapeutic ratio.
The presence of hypoxic regions in solid malignancies is one of the most significant predictive factors affecting the response to radiotherapy in a range of human tumors (reviewed in Ref. ข้อมูลล่าสุด 31/12/2020 03:19:50 ข้อมูลการซื้อขายจะถูกปรับปรุงจากข้อมูลสิ้นวันที่เป็นค่าทางการประมาณ 18:30 น.