tailieunhanh - Báo cáo khoa học: " Investigation of tumor hypoxia using a twoenzyme system for in vitro generation of oxygen deficiency"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Radiation Oncology cung cấp cho các bạn kiến thức về ngành y đề tài: Investigation of tumor hypoxia using a twoenzyme system for in vitro generation of oxygen deficiency. | Askoxylakis et al. Radiation Oncology 2011 6 35 http content 6 1 35 RADIATION ONCOLOGY RESEARCH Open Access Investigation of tumor hypoxia using a two-enzyme system for in vitro generation of oxygen deficiency 2 13 13 4 5 Vasileios Askoxylakis 1 Gunda Millonig Ute Wirkner 1 Christian Schwager 1 Shoaib Rana Annette Altmann Uwe Haberkorn4 5 Jurgen Debus1 Sebastian Mueller2 and Peter E Huber1 3 Abstract Background Oxygen deficiency in tumor tissue is associated with a malign phenotype characterized by high invasiveness increased metastatic potential and poor prognosis. Hypoxia chambers are the established standard model for in vitro studies on tumor hypoxia. An enzymatic hypoxia system GOX CAT based on the use of glucose oxidase GOX and catalase CAT that allows induction of stable hypoxia for in vitro approaches more rapidly and with less operating expense has been introduced recently. Aim of this work is to compare the enzymatic system with the established technique of hypoxia chamber in respect of gene expression glucose metabolism and radioresistance prior to its application for in vitro investigation of oxygen deficiency. Methods Human head and neck squamous cell carcinoma HNO97 cells were incubated under normoxic and hypoxic conditions using both hypoxia chamber and the enzymatic model. Gene expression was investigated using Agilent microarray chips and real time PCR analysis. 14C-fluoro-deoxy-glucose uptake experiments were performed in order to evaluate cellular metabolism. Cell proliferation after photon irradiation was investigated for evaluation of radioresistance under normoxia and hypoxia using both a hypoxia chamber and the enzymatic system. Results The microarray analysis revealed a similar trend in the expression of known HIF-1 target genes between the two hypoxia systems for HNO97 cells. Quantitative RT-PCR demonstrated different kinetic patterns in the expression of carbonic anhydrase IX and lysyl oxidase which might be due to .