56 research outputs found
RRx-001, A novel dinitroazetidine radiosensitizer.
The 'holy grail' in radiation oncology is to improve the outcome of radiation therapy (RT) with a radiosensitizer-a systemic chemical/biochemical agent that additively or synergistically sensitizes tumor cells to radiation in the absence of significant toxicity. Similar to the oxygen effect, in which DNA bases modified by reactive oxygen species prevent repair of the cellular radiation damage, these compounds in general magnify free radical formation, leading to the permanent "fixation" of the resultant chemical change in the DNA structure. The purpose of this review is to present the origin story of the radiosensitizer, RRx-001, which emerged from the aerospace industry. The activity of RRx-001 as a chemosensitizer in multiple tumor types and disease states including malaria, hemorrhagic shock and sickle cell anemia, are the subject of future reviews
RAG-induced DNA double-strand breaks signal through Pim2 to promote pre-B cell survival and limit proliferation
Interleukin 7 (IL-7) promotes preāB cell survival and proliferation by activating the Pim1 and Akt kinases. These signals must be attenuated to induce G1 cell cycle arrest and expression of the RAG endonuclease, which are both required for IgL chain gene rearrangement. As lost IL-7 signals would limit preāB cell survival, how cells survive during IgL chain gene rearrangement remains unclear. We show that RAG-induced DNA double-strand breaks (DSBs) generated during IgL chain gene assembly paradoxically promote preāB cell survival. This occurs through the ATM-dependent induction of Pim2 kinase expression. Similar to Pim1, Pim2 phosphorylates BAD, which antagonizes the pro-apoptotic function of BAX. However, unlike IL-7 induction of Pim1, RAG DSB-mediated induction of Pim2 does not drive proliferation. Rather, Pim2 has antiproliferative functions that prevent the transit of preāB cells harboring RAG DSBs from G1 into S phase, where these DNA breaks could be aberrantly repaired. Thus, signals from IL-7 and RAG DSBs activate distinct Pim kinase family members that have context-dependent activities in regulating preāB cell proliferation and survival
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Hematopoietic Cell Transplantation in Patients With Primary Immune Regulatory Disorders (PIRD): A Primary Immune Deficiency Treatment Consortium (PIDTC) Survey.
Primary Immune Regulatory Disorders (PIRD) are an expanding group of diseases caused by gene defects in several different immune pathways, such as regulatory T cell function. Patients with PIRD develop clinical manifestations associated with diminished and exaggerated immune responses. Management of these patients is complicated; oftentimes immunosuppressive therapies are insufficient, and patients may require hematopoietic cell transplant (HCT) for treatment. Analysis of HCT data in PIRD patients have previously focused on a single gene defect. This study surveyed transplanted patients with a phenotypic clinical picture consistent with PIRD treated in 33 Primary Immune Deficiency Treatment Consortium centers and European centers. Our data showed that PIRD patients often had immunodeficient and autoimmune features affecting multiple organ systems. Transplantation resulted in resolution of disease manifestations in more than half of the patients with an overall 5-years survival of 67%. This study, the first to encompass disorders across the PIRD spectrum, highlights the need for further research in PIRD management
RRx-001, A novel dinitroazetidine radiosensitizer
The āholy grailā in radiation oncology is to improve the outcome of radiation therapy (RT) with a radiosensitizerāa systemic chemical/biochemical agent that additively or synergistically sensitizes tumor cells to radiation in the absence of significant toxicity. Similar to the oxygen effect, in which DNA bases modified by reactive oxygen species prevent repair of the cellular radiation damage, these compounds in general magnify free radical formation, leading to the permanent āfixationā of the resultant chemical change in the DNA structure. The purpose of this review is to present the origin story of the radiosensitizer, RRx-001, which emerged from the aerospace industry. The activity of RRx-001 as a chemosensitizer in multiple tumor types and disease states including malaria, hemorrhagic shock and sickle cell anemia, are the subject of future reviews
Recommended from our members
RRx-001, A novel dinitroazetidine radiosensitizer.
The 'holy grail' in radiation oncology is to improve the outcome of radiation therapy (RT) with a radiosensitizer-a systemic chemical/biochemical agent that additively or synergistically sensitizes tumor cells to radiation in the absence of significant toxicity. Similar to the oxygen effect, in which DNA bases modified by reactive oxygen species prevent repair of the cellular radiation damage, these compounds in general magnify free radical formation, leading to the permanent "fixation" of the resultant chemical change in the DNA structure. The purpose of this review is to present the origin story of the radiosensitizer, RRx-001, which emerged from the aerospace industry. The activity of RRx-001 as a chemosensitizer in multiple tumor types and disease states including malaria, hemorrhagic shock and sickle cell anemia, are the subject of future reviews
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