MOLECULAR DETERMINANTS OF PHOTODYNAMIC THERAPY

描述：（改编自研究者摘要）： 我们的应用是促进光动力疗法的发展 (PDT)通过增加对PDT介导的细胞毒性的分子理解， 并通过制定策略来增强局部杀肿瘤反应， PDT之后。 研究人员将在最近完成的研究基础上 来实现我们的目标 研究人员已经分离出小鼠RIF 纤维肉瘤细胞表现出稳定的PDT抗性表型。 的 研究者还证明PDT介导的氧化应激是一种 属于葡萄糖胁迫蛋白的强转录诱导物 调节蛋白（GRP）家族和热休克蛋白（HSP）家族。 的 研究人员假设，分析PDT耐药性将提供 深入了解PDT诱导细胞毒性的基本机制，从而导致 to strategies战略to improve改善PDT光动力疗法. 研究人员还假设， 使用具有PDT诱导型的重组构建体的靶向基因治疗 启动子驱动细胞毒素的高水平局部表达，和/或 免疫调节剂将增强PDT杀肿瘤作用。 两个具体目标 将解决的假设：1。）来检查分子、细胞和 与我们的PDT抗性细胞相关的体内参数。 的 研究人员将鉴定和表征差异表达的基因 在亲本和PDT抗性RIF肿瘤细胞以及暴露于 PDT介导的细胞毒性。 已鉴定基因在光动力疗法中的作用 敏感性和光敏剂定位将使用向量 介导的基因转移和亚细胞共聚焦荧光显微镜。 2.）使用PDT诱导型启动子选择性地驱动靶基因的表达， 基因. 研究者将使用grp-78和hsp-70启动子/报告基因 构建体，以检查最佳体外和 体内基因表达。 然后，研究人员将评估grp-78， 用于PDT诱导表达的hsp-70启动子/TNF α融合构建体 在培养物中生长或移植到C3 H小鼠中的RIF肿瘤细胞中的TNF α。 研究人员还将检查PDT诱导的有效性。 启动子/TNF α表达构建体，以增强肿瘤杀伤活性。 PDT的有效性。

DESCRIPTION: (Adapted from investigator's abstract): The long term goal of our application is to contribute to the advancement of Photodynamic Therapy (PDT) by increasing the molecular understanding of PDT mediated cytotoxicity and by developing strategies to enhance the local tumoricidal response following PDT. The investigators will build upon recently completed studies to accomplish our objectives. The investigators have isolated mouse RIF fibrosarcoma cells exhibiting a stable PDT resistant phenotype. The investigators have also demonstrated that PDT mediated oxidative stress is a strong transcriptional inducer of stress proteins belonging to the glucose regulated protein (GRP) family and the heat shock protein (HSP) family. The investigators hypothesize that analyzing PDT resistance will provide insights into basic mechanisms of PDT induced cytotoxicity and thereby lead to strategies to improve PDT. The investigators also hypothesize that targeted gene therapy using recombinant constructs with PDT inducible promoters to drive high level local expression of cytotoxins and/or immuno-modulators will enhance PDT tumoricidal action. Two specific aims will address the hypotheses: 1.) to examine the molecular, cellular and in-vivo parameters associated with our PDT resistant cells. The investigators will identify and characterize differentially expressed genes in parental and PDT resistant RIF tumor cells as well as in cells exposed to PDT mediated cytotoxicity. The roles of identified genes in modulating PDT sensitivity and photosensitizer localization will be evaluated using vector mediated gene transfer and subcellular confocal fluorescence microscopy. 2.) to use PDT inducible promoters to selectively drive expression of target genes. The investigators will use grp-78 and hsp-70 promoter/reporter gene constructs to examine PDT parameters required for optimal in-vitro and in-vivo gene expression. The investigators will then evaluate grp-78 and hsp-70 promoter/TNFalpha fusion constructs for PDT induced expression of TNFalpha in RIF tumor cells grown in culture or transplanted into C3H mice. The investigators will also examine the effectiveness of PDT inducible promoter/TNFalpha expression constructs to enhance the tumoricidal effectiveness of PDT.