Chemopotentiation by Low Dose Fractionated Radiation Therapy for disseminated intra-abdominal cancers

低剂量分割放射治疗播散性腹腔内癌症的化学增强作用

基本信息

批准号：
10327267
负责人：
France Carrier
金额：
--
依托单位：
BALTIMORE VA MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-07-01 至 2022-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10327267
关键词：
Abdomen Afghanistan Apoptosis Attention Biological Assay Biological Markers C57BL/6 Mouse CD8-Positive T-Lymphocytes Cancer Patient Carcinogens Carcinomatosis Cells Chemotherapy-Oncologic Procedure Cisplatin Collaborations Combined Modality Therapy DNA Repair Data Disease Dose Down-Regulation Enzymes Exposure to Fluorescence Fluorouracil Fractionated radiotherapy Fukushima Gastric Adenocarcinoma Genes Human Hydrogen Peroxide Hypoxia Immune Immune response Immunocompetent Immunologist Infiltration Injections Intra-abdominal Ionizing radiation Iraq Japan Knowledge Low Dose Radiation Malignant neoplasm of abdomen Malignant neoplasm of gastrointestinal tract Measures Mediating Methods Modeling Molecular Monitor Morphology Mus Normal tissue morphology Nuclear Accidents Nude Mice Oxidases Pathologist Patients Perfusion Peritoneal Post-Transcriptional Regulation Production Proliferating Proteins Radiation Dose Unit Radiation Tolerance Radiation therapy Reactive Oxygen Species Rectal Cancer Recurrence Regimen Regulatory T-Lymphocyte Research Role Serum Stomach Stomach Carcinoma Testing Therapeutic Time Tissues Toxic effect Transcriptional Regulation Up-Regulation Work Xenograft Model Xenograft procedure burn pit cancer therapy chemotherapy clinical application density docetaxel fractionated radiation gastric cancer cell in vivo insight macrophage malignant stomach neoplasm mouse model novel optical imager oxidative damage patient stratification preclinical study programs radiation resistance response stem cells treatment response tumor tumor microenvironment tumor progression

项目摘要

Whole abdominal radiotherapy (WART) is a primary method for managing gastrointestinal cancers that have disseminated into intra-abdominal tissues. While effective, this approach is limited since combination of WART with full-dose chemotherapy regimens increase toxicity to normal tissue. Recent studies have demonstrated a survival advantage in a novel treatment paradigm that allows for the safe use of full-dose systemic chemotherapy in combination with Low Dose Fractionated Radiotherapy (LDFRT). Traditionally, radiotherapy used doses greater than 1.20 Gy because it was thought that lower radiation doses would be ineffective for tumor therapy. We now know that LDFRT can produce hyper-radiosensitivity (HRS), a phenomenon where cells undergo apoptosis at radiation doses as low as 0.15 Gy, in a number of proliferating cells. Our objectives are to develop pre-clinical studies to investigate the therapeutic potential of chemopotentiation by LDFRT in disseminated intra-abdominal cancer. Our data indicate that three consecutive daily fractions of 0.15 Gy produced HRS in gastric cancer cells and potentiated a modified regimen of Docetaxel, Cisplatin, and 5’-fluorouracil (mDCF). Colony survival assays indicated that 0.15 Gy was sufficient to kill 90% of the cells when LDFRT was combined with mDCF whereas an almost ten times higher dose (1.35 Gy) was needed to achieve the same rate when using conventional radiotherapy alone. RT2 PCR Profiler Array analysis of more than 300 genes indicated that Dual Oxidase 2 (DUOX2), an enzyme functioning in the production of hydrogen peroxide, was by far the most upregulated gene in response to this combined regimen while genes involved in DNA repair were apparently not involved. Moreover, down regulation of DUOX2 increased radioresistance at every radiation doses tested. In addition, our data indicate that Reactive Oxygen Species increase up to 3.5 fold in cells exposed to LDFRT and mDCF. Furthermore, inhibition of NAD(P)H oxidase abrogated the killing efficiency of this combined regimen. These findings are particularly important given that DUOX2 is only expressed in about 50% of gastric carcinoma (preliminary data). DUOX2 could thus be used as a biomarker to potentially stratify gastric cancer patients with advanced and metastatic intra-abdominal cancers for clinical applications of chemopotentiation by LDFRT. Our working hypothesis is that Chemopotentiation by LDFRT is mediated by DUOX2 in gastric cancers. In order to test this hypothesis three Specific aims have been developed. Aim 1. Determine the role of DUOX2 on human gastric cancer cells progression in response to chemopotentiation by LDFRT in vivo. We will use human gastric cancer cells expressing endogenous and reduced levels of DUOX2 and a fluorescence marker in mouse xenograft models. Cancer progression will be monitored with a Xenogen IVIS optical imager following treatments. In addition, we will determine whether activation of DUOX2 can be used as a biomarker for the combined regimen by measuring Reactive Oxygen Species (ROS) and oxidative damage to proteins by measuring protein carbonyl levels in mice serum. Aim 2: Delineate the molecular mechanisms leading to DUOX2 upregulation in response to chemopotentiation by LDFRT. Emphasis will be on DUOX2 transcriptional and post-transcriptional regulation. In Aim 3, we will evaluate the effect of DUOX2 on the immune response and the tumor microenvironment. This will be performed in a syngeneic mouse model where DUOX2 effect on vasculature, hypoxia, immune cells infiltration, and stem cells will be monitored. The unique aspect of this proposal is the identification of DUOX2 as a major contributor to chemopotentiatoin by LDFRT and the possibility to revisit WART with radiation doses ten times lower than the conventional dose in an attempt to decrease intra- abdominal recurrence of the disease. In addition to providing insight into the molecular mechanisms underlying therapeutic responses to low dose radiation, these studies could also be used to identify markers for exposure to ionizing radiation.

全腹部放疗（WART）是治疗胃肠道癌症的主要方法，虽然有效，但这种方法受到限制，因为它们的组合。最近的研究表明，全剂量化疗方案的 WART 会增加对正常组织的毒性。新型治疗模式的生存优势，可以证明安全使用全剂量传统上，全身化疗与低剂量分割放射治疗（LDFRT）相结合。使用大于 1.20 Gy 的放射治疗剂量，因为人们认为较低的放射剂量会我们现在知道 LDFRT 会产生高放射敏感性 (HRS)，这是一种细胞在低至 0.15 Gy 的辐射剂量下发生凋亡的现象，在许多增殖细胞中我们的目标是开展临床前研究以研究其治疗潜力。 LDFRT 对播散性腹腔内癌症的化学增强作用我们的数据表明，三种。连续每日 0.15 Gy 的剂量在胃癌细胞中产生 HRS，并增强了改良的多西紫杉醇、顺铂和 5’-氟尿嘧啶 (mDCF) 方案的集落存活测定表明 0.15 Gy 是有效的。当 LDFRT 与 mDCF 结合时，足以杀死 90% 的细胞，而几乎高出十倍单独使用传统放射治疗时需要剂量（1.35 Gy）才能达到相同的速率。 Profiler Array 对 300 多个基因的分析表明，双氧化酶 2 (DUOX2) 是一种具有功能的酶在过氧化氢的产生中，是迄今为止对这种组合反应上调最多的基因而参与 DNA 修复的基因显然没有参与。 DUOX2 在每次测试的辐射剂量下都增加了辐射抗性。此外，我们的数据表明，反应性。暴露于 LDFRT 和 mDCF 的细胞中的氧种类增加高达 3.5 倍。 NAD(P)H 氧化酶消除了这种联合疗法的杀灭效率。这些发现尤其重要。鉴于 DUOX2 仅在约 50% 的胃癌中表达（初步数据），这一点很重要。因此可以用作生物标志物，对晚期和转移性胃癌患者进行潜在分层我们的工作假设是 LDFRT 化学增强的临床应用。 LDFRT 的化学增效是由胃癌中的 DUOX2 介导的。制定了三个具体目标目的 1. 确定 DUOX2 对人胃癌细胞的作用。我们将使用人胃癌细胞来研究体内 LDFRT 化学增强反应的进展。在小鼠异种移植模型中表达内源性和降低水平的 DUOX2 和荧光标记。治疗后，我们将使用 Xenogen IVIS 光学成像仪监测癌症进展。将确定 DUOX2 的激活是否可以用作联合治疗方案的生物标志物通过测量蛋白质羰基来测量活性氧 (ROS) 和蛋白质的氧化损伤目标 2：描述导致 DUOX2 响应上调的分子机制。通过 LDFRT 进行化学增效，重点是 DUOX2 转录和转录后。在目标3中，我们将评估DUOX2对免疫反应和肿瘤的影响。这将在同基因小鼠模型中进行，其中 DUOX2 对脉管系统有影响，该提案的独特之处在于将监测缺氧、免疫细胞浸润和干细胞。通过 LDFRT 鉴定 DUOX2 作为化学增效的主要贡献者以及重新审视的可能性 WART 的辐射剂量比常规剂量低十倍，试图减少体内除了提供对分子机制的深入了解之外。对低剂量辐射的潜在治疗反应，这些研究也可用于识别标记物用于暴露于电离辐射。