Iron, NO, and Lipid Peroxide in Photodynamic Therapy

光动力疗法中的铁、一氧化氮和过氧化脂质

• 批准号: 8677707
• 负责人: Albert Girotti
• 金额: $ 24.15万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-12-15 至 2016-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8677707
• 关键词: Adenocarcinoma; Affect; Aminolevulinic Acid; Animal Model; Animals; Anti-Asthmatic Agents; Apoptosis; Apoptotic; BCL2 gene; BODIPY; Bax protein; Biological Process; Breast; Breast Carcinoma; Caspase; Cell Death; Cell membrane; Cells; Chemicals; Clinical; Confocal Microscopy; Cultured Cells; Cyclic GMP; Cytoprotection; Diffuse; Dose; Effectiveness; Environmental Risk Factor; Enzymes; Esters; Evaluation; Event; Ferritin; Future; Generations; Goals; Grant; Growth; Heme; Human; Hydrogen Peroxide; Immunoblotting; Implant; In Vitro; Iron; Laboratories; Learning; Light; Lipid Peroxides; Lipids; MAPK11 gene; MAPK14 gene; MAPK3 gene; MAPK8 gene; MDA MB 231; Malignant Epithelial Cell; Malignant Neoplasms; Mammary Neoplasms; Metabolic; Methodology; Methods; Mitochondria; Mitogen-Activated Protein Kinases; Modality; Modeling; Molecular; Molecular Target; Monitor; Mus; NG-Nitroarginine Methyl Ester; Necrosis; Nitric Oxide; Nitric Oxide Donors; Nitric Oxide Synthase; Oxidants; Oxidation-Reduction; Oxidative Stress; Oxygen; PTGS2 gene; Pathway interactions; Peripheral; Photochemotherapy; Porfimer Sodium; Prostate; Prostate carcinoma; Protein Isoforms; Public Health; RNA Interference; Relative (related person); Reporting; Resistance; Role; SCID Mice; Signal Transduction; Singlet Oxygen; Site; Skin; Skin Carcinoma; Small Interfering RNA; Soluble Guanylate Cyclase; Squamous Cell Breast Carcinoma; Stress; Testing; Time; Topical application; Transcription Factor AP-1; Treatment Efficacy; Tumor Cell Line; Up-Regulation; Variant; Visible Radiation; Work; Xenograft Model; base; biological adaptation to stress; cancer cell; cancer therapy; cell killing; cell type; cytotoxic; diacetyldichlorofluorescein; extracellular signal-regulated kinase 3; heme oxygenase-1; human NOS2A protein; immunosuppressed; improved; in vitro Model; in vivo Model; inhibitor/antagonist; innovation; irradiation; kinase inhibitor; neoplastic cell; novel; overexpression; prevent; response; small hairpin RNA; stress-activated protein kinase 1; survivin; therapy outcome; transcription factor; tumor; tumor growth

DESCRIPTION (provided by applicant): Photodynamic therapy (PDT), a unique antitumor modality involving a sensitizing agent, photoexciting light and molecular oxygen, is characterized by local generation of singlet oxygen and other cytotoxic oxidants. When subjected to PDT-induced oxidative stress, many tumors succumb to apoptotic cell death, and much has been learned about how this is affected by factors such as sensitizer localization and efficiency of toxic oxidant generation. However, the influence of metabolic and environmental factors, is still not well understood. Studies supported by the existing grant have focused largely on the effects of nitric oxide (NO) in this regard. Nitric oxide synthase (NOS)-generated NO in low doses is known to have pro-survival and growth-promoting effects on various tumors. Using in vitro models of 5- aminolevulinic acid (ALA)-based PDT and chemical NO donors, we have shown that NO can protect tumor cells against necrotic photokilling by either scavenging lipid-derived radicals or by signaling for heme oxygenase-1 and ferritin induction, leading to depletion of prooxidant iron. We recently discovered that NO is overproduced by ALA/light-stressed breast tumor cells due to rapid and prolonged upregulation of inducible NOS and that this substantially increases cell resistance to intrinsic apoptotic photokilling. This proposal developed largely from this novel observation and is based on the following hypothesis: Under PDT stress, many tumors will overexpress NOS and NO as a cytoprotective response, and this can compromise PDT efficacy. Our overall plan for testing this hypothesis is to study: (i) relative abilities of various established breast, prostate, and skin carcinoma cells to overexpress cytoprotective NOS/NO under ALA/light stress; (ii) mechanisms of NOS induction by photostress; (iii) cytoprotective mechanisms of stress-induced NO; (iv) effects of this NO on bystander cells; and (v) PDT induction of NOS/NO in a mouse xenograft model and NOS inhibitor effects. Planned methods include: cultured cell sensitization, irradiation, and apoptosis evaluation; use of NOS inhibitors, NO scavengers, and chemical NO donors; RNA interference; immunoblotting; confocal microscopy; and PDT of human tumors implanted in immunosuppressed mice; in addition to ALA-PDT, classical Photofrin-PDT will be used. This proposal is significant and innovative for the following reasons: (i) Although positive effects of NOS inhibitors in animal tumor PDT have been reported, there is no known evidence for endogenous NOS/NO upregulation due to PDT; (ii) The prospect of eventually using NOS inhibitors to improve clinical PDT outcomes is favorable, given that human testing of at least one of those to be studied, GW274150 (as an anti-asthmatic), has been reported.

描述（由申请人提供）：光动力疗法（PDT）是一种独特的抗肿瘤疗法，涉及敏化剂、光激发光和分子氧，其特征在于局部产生单线态氧和其他细胞毒性氧化剂。当受到PDT诱导的氧化应激时，许多肿瘤屈服于凋亡性细胞死亡，并且已经了解到这是如何受到诸如敏化剂定位和毒性氧化剂生成效率等因素的影响的。然而，代谢和环境因素的影响，仍然没有得到很好的理解。由现有拨款资助的研究主要集中在一氧化氮（NO）在这方面的影响。已知低剂量的一氧化氮合酶（NOS）产生的NO对各种肿瘤具有促存活和生长促进作用。使用基于5-氨基乙酰丙酸（ALA）的PDT和化学NO供体的体外模型，我们已经表明，NO可以通过清除脂质衍生的自由基或通过血红素加氧酶-1和铁蛋白诱导的信号传导来保护肿瘤细胞免受坏死性光杀伤，从而导致促氧化剂铁的耗尽。我们最近发现，由于诱导型NOS的快速和长期上调，ALA/光应激乳腺肿瘤细胞过度产生NO，这大大增加了细胞对内在凋亡光杀伤的抵抗力。这一提议主要是从这一新的观察结果发展而来，并基于以下假设：在PDT应激下，许多肿瘤将过度表达NOS和NO作为细胞保护反应，这可能会损害PDT的疗效。我们检验这一假设的总体计划是研究：（i）各种已建立的乳腺癌、前列腺癌和皮肤癌细胞在ALA/光应激下过表达细胞保护性NOS/NO的相对能力;（ii）光应激诱导NOS的机制;（iii）应激诱导的NO的细胞保护机制;（iv）这种NO对旁观者细胞的影响;（iv）光应激诱导的NOS/NO的表达。和（v）小鼠异种移植模型中NOS/NO的PDT诱导和NOS抑制剂作用。计划的方法包括：培养的细胞致敏、辐照和凋亡评价; NOS抑制剂、NO清除剂和化学NO供体的使用; RNA干扰;免疫印迹;共聚焦显微镜;以及植入免疫抑制小鼠中的人肿瘤的PDT;除了ALA-PDT之外，还将使用经典的Photofrin-PDT。（i）虽然已经报道了NOS抑制剂在动物肿瘤PDT中的积极作用，但是没有已知的证据表明PDT导致内源性NOS/NO上调;（ii）最终使用NOS抑制剂来改善临床PDT结果的前景是有利的，因为至少一种待研究的NOS抑制剂的人体测试，GW 274150（作为抗哮喘药），已有报道。