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1.
Mol Cancer Ther ; 23(4): 577-588, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38359816

RESUMO

Treatments involving radiation and chemotherapy alone or in combination have improved patient survival and quality of life. However, cancers frequently evade these therapies due to adaptation and tumor evolution. Given the complexity of predicting response based solely on the initial genetic profile of a patient, a predetermined treatment course may miss critical adaptation that can cause resistance or induce new targets for drug and immunotherapy. To address the timescale for these evasive mechanisms, using a mouse xenograft tumor model, we investigated the rapidity of gene expression (mRNA), molecular pathway, and phosphoproteome changes after radiation, an HSP90 inhibitor, or combination. Animals received radiation, drug, or combination treatment for 1 or 2 weeks and were then euthanized along with a time-matched untreated group for comparison. Changes in gene expression occur as early as 1 week after treatment initiation. Apoptosis and cell death pathways were activated in irradiated tumor samples. For the HSP90 inhibitor and combination treatment at weeks 1 and 2 compared with Control Day 1, gene-expression changes induced inhibition of pathways including invasion of cells, vasculogenesis, and viral infection among others. The combination group included both drug-alone and radiation-alone changes. Our data demonstrate the rapidity of gene expression and functional pathway changes in the evolving tumor as it responds to treatment. Discovering these phenotypic adaptations may help elucidate the challenges in using sustained treatment regimens and could also define evolving targets for therapeutic efficacy.


Assuntos
Antineoplásicos , Neoplasias , Animais , Humanos , Xenoenxertos , Multiômica , Qualidade de Vida , Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/radioterapia , Proteínas de Choque Térmico HSP90 , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Pract Radiat Oncol ; 13(5): e383-e388, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37150318

RESUMO

We present the case of a woman with metastatic adenoid cystic carcinoma who received stereotactic ablative radiation therapy with a total dose of 50 Gy in 4 fractions to 2 lung metastases and developed symptomatic left phrenic nerve injury 2 years after radiation. The maximum dose to the approximate location of the phrenic nerve was 57.7 Gy, which corresponds to a biologically effective dose for late effects (using α/ß ratio = 3) of 335.14 Gy. Here, we discuss the case, planning considerations by radiation oncologists and medical physicists, and the multidisciplinary medical management of this patient.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Paralisia Respiratória , Feminino , Humanos , Nervo Frênico/patologia , Paralisia Respiratória/etiologia , Neoplasias Pulmonares/patologia , Radiocirurgia/efeitos adversos , Progressão da Doença
3.
Int J Radiat Biol ; 99(11): 1702-1715, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37212632

RESUMO

PURPOSE: Previous research has highlighted the impact of radiation damage, with cancer patients developing acute disorders including radiation induced pneumonitis or chronic disorders including pulmonary fibrosis months after radiation therapy ends. We sought to discover biomarkers that predict these injuries and develop treatments that mitigate this damage and improve quality of life. MATERIALS AND METHODS: Six- to eight-week-old female C57BL/6 mice received 1, 2, 4, 8, 12 Gy or sham whole body irradiation. Animals were euthanized 48 h post exposure and lungs removed, snap frozen and underwent RNA isolation. Microarray analysis was performed to determine dysregulation of messenger RNA (mRNA), microRNA (miRNA), and long non-coding RNA (lncRNA) after radiation injury. RESULTS: We observed sustained dysregulation of specific RNA markers including: mRNAs, lncRNAs, and miRNAs across all doses. We also identified significantly upregulated genes that can indicate high dose exposure, including Cpt1c, Pdk4, Gdf15, and Eda2r, which are markers of senescence and fibrosis. Only three miRNAs were significantly dysregulated across all radiation doses: miRNA-142-3p and miRNA-142-5p were downregulated and miRNA-34a-5p was upregulated. IPA analysis predicted inhibition of several molecular pathways with increasing doses of radiation, including: T cell development, Quantity of leukocytes, Quantity of lymphocytes, and Cell viability. CONCLUSIONS: These RNA biomarkers might be highly relevant in the development of treatments and in predicting normal tissue injury in patients undergoing radiation treatment. We are conducting further experiments in our laboratory, which includes a human lung-on-a-chip model, to develop a decision tree model using RNA biomarkers.


Assuntos
MicroRNAs , Irradiação Corporal Total , Camundongos , Animais , Humanos , Irradiação Corporal Total/efeitos adversos , Qualidade de Vida , Camundongos Endogâmicos C57BL , Pulmão/efeitos da radiação , MicroRNAs/genética , MicroRNAs/metabolismo , Biomarcadores/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Modelos Animais de Doenças , Receptor Xedar/genética , Receptor Xedar/metabolismo
4.
Sci Rep ; 12(1): 3500, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241721

RESUMO

The efficacy of molecular targeted therapy depends on expression and enzymatic activity of the target molecules. As radiotherapy modulates gene expression and protein phosphorylation dependent on dose and fractionation, we analyzed the long-term effects of irradiation on the post-radiation efficacy of molecular targeted drugs. We irradiated prostate cancer cells either with a single dose (SD) of 10 Gy x-ray or a multifractionated (MF) regimen with 10 fractions of 1 Gy. Whole genome arrays and reverse phase protein microarrays were used to determine gene expression and protein phosphorylation. Additionally, we evaluated radiation-induced pathway activation with the Ingenuity Pathway Analysis software. To measure cell survival and sensitivity to clinically used molecular targeted drugs, we performed colony formation assays. We found increased activation of several pathways regulating important cell functions such as cell migration and cell survival at 24 h after MF irradiation or at 2 months after SD irradiation. Further, cells which survived a SD of 10 Gy showed a long-term upregulation and increased activity of multiple molecular targets including AKT, IGF-1R, VEGFR2, or MET, while HDAC expression was decreased. In line with this, 10 Gy SD cells were more sensitive to target inhibition with Capivasertib or Ipatasertib (AKTi), BMS-754807 (IGF-1Ri), or Foretinib (VEGFR2/METi), but less sensitive to Panobinostat or Vorinostat (HDACi). In summary, understanding the molecular short- and long-term changes after irradiation can aid in optimizing the efficacy of multimodal radiation oncology in combination with post-irradiation molecularly-targeted drug treatment and improving the outcome of prostate cancer patients.


Assuntos
Neoplasias da Próstata , Radioterapia (Especialidade) , Sobrevivência Celular , Fracionamento da Dose de Radiação , Humanos , Masculino , Próstata/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/radioterapia
5.
Cancer Immunol Immunother ; 71(4): 839-850, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34435232

RESUMO

The expression of immune-related genes in cancer cells can alter the anti-tumor immune response and thereby impact patient outcomes. Radiotherapy has been shown to modulate immune-related genes dependent on the fractionation regimen. To identify long-term changes in gene expression after irradiation, PC3 (p53 deleted) and LNCaP (p53 wildtype) prostate cancer cells were irradiated with either a single dose (SD, 10 Gy) or a fractionated regimen (MF) of 10 fractions (1 Gy per fraction). Whole human genome arrays were used to determine gene expression at 24 h and 2 months after irradiation. Immune pathway activation was analyzed with Ingenuity Pathway Analysis software. Additionally, 3D colony formation assays and T-cell cytotoxicity assays were performed. LNCaP had a higher basal expression of immunogenic genes and was more efficiently killed by cytotoxic T-cells compared to PC3. In both cell lines, MF irradiation resulted in an increase in multiple immune-related genes immediately after irradiation, while at 2 months, SD irradiation had a more pronounced effect on radiation-induced gene expression. Both immunogenic and immunosuppressive genes were upregulated in the long term in PC3 cells by a 10 Gy SD irradiation but not in LNCaP. T-cell-mediated cytotoxicity was significantly increased in 10 Gy SD PC3 cells compared to the unirradiated control and could be further enhanced by treatment with immune checkpoint inhibitors. Irradiation impacts the expression of immune-related genes in cancer cells in a fractionation-dependent manner. Understanding and targeting these changes may be a promising strategy for primary prostate cancer and recurrent tumors.


Assuntos
Recidiva Local de Neoplasia , Neoplasias da Próstata , Apoptose , Linhagem Celular Tumoral , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/radioterapia
6.
J Transl Med ; 19(1): 336, 2021 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-34364390

RESUMO

BACKGROUND: Radiation therapy is integral to effective thoracic cancer treatments, but its application is limited by sensitivity of critical organs such as the heart. The impacts of acute radiation-induced damage and its chronic effects on normal heart cells are highly relevant in radiotherapy with increasing lifespans of patients. Biomarkers for normal tissue damage after radiation exposure, whether accidental or therapeutic, are being studied as indicators of both acute and delayed effects. Recent research has highlighted the potential importance of RNAs, including messenger RNAs (mRNAs), microRNAs (miRNAs), and long non-coding RNAs (lncRNAs) as biomarkers to assess radiation damage. Understanding changes in mRNA and non-coding RNA expression will elucidate biological pathway changes after radiation. METHODS: To identify significant expression changes in mRNAs, lncRNAs, and miRNAs, we performed whole transcriptome microarray analysis of mouse heart tissue at 48 h after whole-body irradiation with 1, 2, 4, 8, and 12 Gray (Gy). We also validated changes in specific lncRNAs through RT-qPCR. Ingenuity Pathway Analysis (IPA) was used to identify pathways associated with gene expression changes. RESULTS: We observed sustained increases in lncRNAs and mRNAs, across all doses of radiation. Alas2, Aplnr, and Cxc3r1 were the most significantly downregulated mRNAs across all doses. Among the significantly upregulated mRNAs were cell-cycle arrest biomarkers Gdf15, Cdkn1a, and Ckap2. Additionally, IPA identified significant changes in gene expression relevant to senescence, apoptosis, hemoglobin synthesis, inflammation, and metabolism. LncRNAs Abhd11os, Pvt1, Trp53cor1, and Dino showed increased expression with increasing doses of radiation. We did not observe any miRNAs with sustained up- or downregulation across all doses, but miR-149-3p, miR-6538, miR-8101, miR-7118-5p, miR-211-3p, and miR-3960 were significantly upregulated after 12 Gy. CONCLUSIONS: Radiation-induced RNA expression changes may be predictive of normal tissue toxicities and may indicate targetable pathways for radiation countermeasure development and improved radiotherapy treatment plans.


Assuntos
MicroRNAs , RNA Longo não Codificante , 5-Aminolevulinato Sintetase , Animais , Redes Reguladoras de Genes , Humanos , Camundongos , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Irradiação Corporal Total
7.
Mol Ther Nucleic Acids ; 24: 175-187, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-33767914

RESUMO

Long non-coding RNAs (lncRNAs) have been shown to impact important biological functions such as proliferation, survival, and genomic stability. To analyze radiation-induced lncRNA expression in human tumors, we irradiated prostate cancer cells with a single dose of 10 Gy or a multifractionated radiotherapeutic regimen of 10 fractions with a dose of 1 Gy (10 × 1 Gy) during 5 days. We found a stable upregulation of the lncRNA LINC00261 and LINC00665 at 2 months after radiotherapy that was more pronounced after single-dose irradiation. Analysis of the The Cancer Genome Atlas (TCGA) and The Atlas of Non-coding RNAs in Cancer (TANRIC) databases showed that high expression of these two lncRNAs may be a potential negative prognostic marker for overall survival of prostate cancer patients. Knockdown of LINC00261 and LINC00665 in long-term survivors decreased survival after re-irradiation and affected DNA double-strand break repair. Mechanistically, both lncRNAs showed an interdependent expression and regulated expression of the DNA repair proteins CtIP (RBBP8) and XPC as well as the microRNA miR-329. Identifying long-term tumor adaptation mechanisms can lead to the discovery of new molecular targets, in effect opening up new research directions and improving multimodal radiation oncologic treatment.

8.
Clin Cancer Res ; 26(22): 5781-5790, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32554542

RESUMO

Radiotherapy is highly effective due to its ability to physically focus the treatment to target the tumor while sparing normal tissue and its ability to be combined with systemic therapy. This systemic therapy can be utilized before radiotherapy as an adjuvant or induction treatment, during radiotherapy as a radiation "sensitizer," or following radiotherapy as a part of combined modality therapy. As part of a unique concept of using radiation as "focused biology," we investigated how tumors and normal tissues adapt to clinically relevant multifraction (MF) and single-dose (SD) radiation to observe whether the adaptations can induce susceptibility to cell killing by available drugs or by immune enhancement. We identified an adaptation occurring after MF (3 × 2 Gy) that induced cell killing when AKT-mTOR inhibitors were delivered following cessation of radiotherapy. In addition, we identified inducible changes in integrin expression 2 months following cessation of radiotherapy that differ between MF (1 Gy × 10) and SD (10 Gy) that remain targetable compared with preradiotherapy. Adaptation is reflected across different "omics" studies, and thus the range of possible molecular targets is not only broad but also time, dose, and schedule dependent. While much remains to be studied about the radiation adaptive response, radiation should be characterized by its molecular perturbations in addition to physical dose. Consideration of the adaptive effects should result in the design of a tailored radiotherapy treatment plan that accounts for specific molecular changes to be targeted as part of precision multimodality cancer treatment.


Assuntos
Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Lesões por Radiação/tratamento farmacológico , Lesões por Radiação/radioterapia , Terapia Combinada , Fracionamento da Dose de Radiação , Humanos , Imunoterapia , Neoplasias/genética , Neoplasias/patologia , Proteína Oncogênica v-akt/antagonistas & inibidores , Lesões por Radiação/patologia , Dosagem Radioterapêutica , Serina-Treonina Quinases TOR/antagonistas & inibidores
9.
Nucleic Acids Res ; 48(3): 1314-1326, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-31822909

RESUMO

Multifractionated irradiation is the mainstay of radiation treatment in cancer therapy. Yet, little is known about the cellular DNA repair processes that take place between radiation fractions, even though understanding the molecular mechanisms promoting cancer cell recovery and survival could improve patient outcome and identify new avenues for targeted intervention. To address this knowledge gap, we systematically characterized how cells respond differentially to multifractionated and single-dose radiotherapy, using a combination of genetics-based and functional approaches. We found that both cancer cells and normal fibroblasts exhibited enhanced survival after multifractionated irradiation compared with an equivalent single dose of irradiation, and this effect was entirely dependent on 53BP1-mediated NHEJ. Furthermore, we identified RIF1 as the critical effector of 53BP1. Inhibiting 53BP1 recruitment to damaged chromatin completely abolished the survival advantage after multifractionated irradiation and could not be reversed by suppressing excessive end resection. Analysis of the TCGA database revealed lower expression of 53BP1 pathway genes in prostate cancer, suggesting that multifractionated radiotherapy might be a favorable option for radio-oncologic treatment in this tumor type. We propose that elucidation of DNA repair mechanisms elicited by different irradiation dosing regimens could improve radiotherapy selection for the individual patient and maximize the efficacy of radiotherapy.


Assuntos
Sobrevivência Celular/genética , Neoplasias da Próstata/radioterapia , Proteínas de Ligação a Telômeros/genética , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Animais , Sobrevivência Celular/efeitos da radiação , Cromatina/efeitos da radiação , Reparo do DNA por Junção de Extremidades/genética , Reparo do DNA/genética , Reparo do DNA/efeitos da radiação , Fibroblastos/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Células HeLa , Humanos , Masculino , Camundongos , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Transdução de Sinais/efeitos da radiação
10.
Mol Cancer Res ; 16(12): 1855-1864, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30042176

RESUMO

Adaptation of tumor cells to radiotherapy induces changes that are actionable by molecular targeted agents and immunotherapy. This report demonstrates that radiation-induced changes in integrin expression can be targeted 2 months later. Integrins are transmembrane cell adhesion molecules that are essential for cancer cell survival and proliferation. To analyze the short- and long-term effects of radiation on the integrin expression, prostate cancer cells (DU145, PC3, and LNCaP) were cultured in a 3D extracellular matrix and irradiated with either a single dose of radiation (2-10 Gy) or a multifractionated regimen (2-10 fractions of 1 Gy). Whole human genome microarrays, immunoblotting, immunoprecipitation assays, and immunofluorescence staining of integrins were performed. The results were confirmed in a prostate cancer xenograft model system. Interestingly, ß1 and ß4 integrins (ITGB1 and ITGB4) were upregulated after radiation in vitro and in vivo. This overexpression lasted for more than 2 months and was dose dependent. Moreover, radiation-induced upregulation of ß1 and ß4 integrin resulted in significantly increased tumor cell death after treatment with inhibitory antibodies. Combined, these findings indicate that long-term tumor adaptation to radiation can result in an increased susceptibility of surviving cancer cells to molecular targeted therapy due to a radiation-induced overexpression of the target. IMPLICATIONS: Radiation induces dose- and schedule-dependent adaptive changes that are targetable for an extended time; thus suggesting radiotherapy as a unique strategy to orchestrate molecular processes, thereby providing new radiation-drug treatment options within precision cancer medicine.


Assuntos
Antineoplásicos Imunológicos/administração & dosagem , Cadeias beta de Integrinas/genética , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Animais , Antineoplásicos Imunológicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Terapia Combinada , Relação Dose-Resposta à Radiação , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Cadeias beta de Integrinas/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Integrina beta4/genética , Integrina beta4/metabolismo , Masculino , Camundongos , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Tolerância a Radiação/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Biomarkers ; 23(7): 689-703, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29799276

RESUMO

CONTEXT: Accidental exposure to life-threatening radiation in a nuclear event is a major concern; there is an enormous need for identifying biomarkers for radiation biodosimetry to triage populations and treat critically exposed individuals. OBJECTIVE: To identify dose-differentiating miRNA signatures from whole blood samples of whole body irradiated mice. METHODS: Mice were whole body irradiated with X-rays (2 Gy-15 Gy); blood was collected at various time-points post-exposure; total RNA was isolated; miRNA microarrays were performed; miRNAs differentially expressed in irradiated vs. unirradiated controls were identified; feature extraction and classification models were applied to predict dose-differentiating miRNA signature. RESULTS: We observed a time and dose responsive alteration in the expression levels of miRNAs. Maximum number of miRNAs were altered at 24-h and 48-h time-points post-irradiation. A 23-miRNA signature was identified using feature selection algorithms and classifier models. An inverse correlation in the expression level changes of miR-17 members, and their targets were observed in whole body irradiated mice and non-human primates. CONCLUSION: Whole blood-based miRNA expression signatures might be used for predicting radiation exposures in a mass casualty nuclear incident.


Assuntos
MicroRNAs/sangue , Análise em Microsséries/métodos , Irradiação Corporal Total/efeitos adversos , Animais , Relação Dose-Resposta à Radiação , Perfilação da Expressão Gênica , Camundongos , Exposição à Radiação/efeitos adversos , Fatores de Tempo
13.
Radiat Res ; 189(3): 251-263, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29309266

RESUMO

Long noncoding RNAs (lncRNAs) are emerging as key molecules in regulating many biological processes and have been implicated in development and disease pathogenesis. Biomarkers of cancer and normal tissue response to treatment are of great interest in precision medicine, as well as in public health and medical management, such as for assessment of radiation injury after an accidental or intentional exposure. Circulating and functional RNAs, including microRNAs (miRNAs) and lncRNAs, in whole blood and other body fluids are potential valuable candidates as biomarkers. Early prediction of possible acute, intermediate and delayed effects of radiation exposure enables timely therapeutic interventions. To address whether long noncoding RNAs (lncRNAs) could serve as biomarkers for radiation biodosimetry we performed whole genome transcriptome analysis in a mouse model after whole-body irradiation. Differential lncRNA expression patterns were evaluated at 16, 24 and 48 h postirradiation in total RNA isolated from whole blood of mice exposed to 1, 2, 4, 8 and 12 Gy of X rays. Sham-irradiated animals served as controls. Significant alterations in the expression patterns of lncRNAs were observed after different radiation doses at the various time points. We identified several radiation-induced lncRNAs known for DNA damage response as well as immune response. Long noncoding RNA targets of tumor protein 53 (P53), Trp53cor1, Dino, Pvt1 and Tug1 and an upstream regulator of p53, Meg3, were altered in response to radiation. Gm14005 ( Morrbid) and Tmevpg1 were regulated by radiation across all time points and doses. These two lncRNAs have important potential as blood-based radiation biomarkers; Gm14005 ( Morrbid) has recently been shown to play a key role in inflammatory response, while Tmevpg1 has been implicated in the regulation of interferon gamma. Precise molecular biomarkers, likely involving a diverse group of inducible molecules, will not only enable the development and effective use of medical countermeasures but may also be used to detect and circumvent or mitigate normal tissue injury in cancer radiotherapy.


Assuntos
RNA Longo não Codificante/genética , Irradiação Corporal Total/efeitos adversos , Animais , Biomarcadores/sangue , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Relação Dose-Resposta à Radiação , Feminino , Genômica , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Tempo , Transcriptoma/efeitos da radiação , Proteína Supressora de Tumor p53/metabolismo
14.
Mol Cancer Ther ; 17(2): 355-367, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28802252

RESUMO

Implementing targeted drug therapy in radio-oncologic treatment regimens has greatly improved the outcome of cancer patients. However, the efficacy of molecular targeted drugs such as inhibitory antibodies or small molecule inhibitors essentially depends on target expression and activity, which both can change during the course of treatment. Radiotherapy has previously been shown to activate prosurvival pathways, which can help tumor cells to adapt and thereby survive treatment. Therefore, we aimed to identify changes in signaling induced by radiation and evaluate the potential of targeting these changes with small molecules to increase the therapeutic efficacy on cancer cell survival. Analysis of "The Cancer Genome Atlas" database disclosed a significant overexpression of AKT1, AKT2, and MTOR genes in human prostate cancer samples compared with normal prostate gland tissue. Multifractionated radiation of three-dimensional-cultured prostate cancer cell lines with a dose of 2 Gy/day as a clinically relevant schedule resulted in an increased protein phosphorylation and enhanced protein-protein interaction between AKT and mTOR, whereas gene expression of AKT, MTOR, and related kinases was not altered by radiation. Similar results were found in a xenograft model of prostate cancer. Pharmacologic inhibition of mTOR/AKT signaling after activation by multifractionated radiation was more effective than treatment prior to radiotherapy. Taken together, our findings provide a proof-of-concept that targeting signaling molecules after activation by radiotherapy may be a novel and promising treatment strategy for cancers treated with multifractionated radiation regimens such as prostate cancer to increase the sensitivity of tumor cells to molecular targeted drugs. Mol Cancer Ther; 17(2); 355-67. ©2017 AACRSee all articles in this MCT Focus section, "Developmental Therapeutics in Radiation Oncology."


Assuntos
Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Benzoxazóis/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Camundongos , Camundongos Nus , Piperazinas/farmacologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas/farmacologia , Distribuição Aleatória , Transdução de Sinais/efeitos da radiação , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Natl Cancer Inst ; 110(4): 329-340, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29126306

RESUMO

Innovation and progress in radiation oncology depend on discovery and insights realized through research in radiation biology. Radiobiology research has led to fundamental scientific insights, from the discovery of stem/progenitor cells to the definition of signal transduction pathways activated by ionizing radiation that are now recognized as integral to the DNA damage response (DDR). Radiobiological discoveries are guiding clinical trials that test radiation therapy combined with inhibitors of the DDR kinases DNA-dependent protein kinase (DNA-PK), ataxia telangiectasia mutated (ATM), ataxia telangiectasia related (ATR), and immune or cell cycle checkpoint inhibitors. To maintain scientific and clinical relevance, the field of radiation biology must overcome challenges in research workforce, training, and funding. The National Cancer Institute convened a workshop to discuss the role of radiobiology research and radiation biologists in the future scientific enterprise. Here, we review the discussions of current radiation oncology research approaches and areas of scientific focus considered important for rapid progress in radiation sciences and the continued contribution of radiobiology to radiation oncology and the broader biomedical research community.


Assuntos
Pesquisa Biomédica , Neoplasias/radioterapia , Radiobiologia , Animais , Humanos , Transdução de Sinais
16.
Radiat Res ; 188(1): 1-20, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28489488

RESUMO

A workshop entitled "Radiation-Induced Fibrosis: Mechanisms and Opportunities to Mitigate" (held in Rockville, MD, September 19, 2016) was organized by the Radiation Research Program and Radiation Oncology Branch of the Center for Cancer Research (CCR) of the National Cancer Institute (NCI), to identify critical research areas and directions that will advance the understanding of radiation-induced fibrosis (RIF) and accelerate the development of strategies to mitigate or treat it. Experts in radiation biology, radiation oncology and related fields met to identify and prioritize the key areas for future research and clinical translation. The consensus was that several known and newly identified targets can prevent or mitigate RIF in pre-clinical models. Further, basic and translational research and focused clinical trials are needed to identify optimal agents and strategies for therapeutic use. It was felt that optimally designed preclinical models are needed to better study biomarkers that predict for development of RIF, as well as to understand when effective therapies need to be initiated in relationship to manifestation of injury. Integrating appropriate endpoints and defining efficacy in clinical trials testing treatment of RIF were felt to be critical to demonstrating efficacy. The objective of this meeting report is to (a) highlight the significance of RIF in a global context, (b) summarize recent advances in our understanding of mechanisms of RIF,


Assuntos
Fibrose Pulmonar/diagnóstico , Fibrose Pulmonar/terapia , Pneumonite por Radiação/diagnóstico , Pneumonite por Radiação/terapia , Radioterapia/efeitos adversos , Medicina Baseada em Evidências , Humanos , National Cancer Institute (U.S.) , Fibrose Pulmonar/etiologia , Pneumonite por Radiação/etiologia , Resultado do Tratamento , Estados Unidos
17.
Semin Radiat Oncol ; 26(4): 254-60, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27619247

RESUMO

The dramatic changes in the technological delivery of radiation therapy, the repertoire of molecular targets for which pathway inhibitors are available, and the cellular and immunologic responses that can alter long-term clinical outcome provide a potentially unique role for using the radiation-inducible changes as therapeutic targets. Various mathematical models of dose and fractionation are extraordinarily useful in guiding treatment regimens. However, although the model may fit the clinical outcome, a deeper understanding of the molecular and cellular effect of the individual dose size and the adaptation to repeated exposure, called multifraction (MF) adaptation, may provide new therapeutic targets for use in combined modality treatments using radiochemotherapy and radioimmunotherapy. We discuss the potential of using different radiation doses and MF adaptation for targeting transcription factors, immune and inflammatory response, and cell "stemness." Given the complex genetic composition of tumors before treatment and their adaptation to drug treatment, innovative combinations using both the pretreatment molecular data and also the MF-adaptive response to radiation may provide an important role for focused radiation therapy as an integral part of precision medicine and immunotherapy.


Assuntos
Neoplasias/genética , Neoplasias/radioterapia , Quimiorradioterapia , Terapia Combinada , Fracionamento da Dose de Radiação , Humanos , Cinética , Medicina de Precisão , Hipofracionamento da Dose de Radiação , Radioimunoterapia
18.
Cancer Lett ; 382(1): 118-126, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-26828133

RESUMO

New technologies enabling the analysis of various molecules, including DNA, RNA, proteins and small metabolites, can aid in understanding the complex molecular processes in cancer cells. In particular, for the use of novel targeted therapeutics, elucidation of the mechanisms leading to cell death or survival is crucial to eliminate tumor resistance and optimize therapeutic efficacy. While some techniques, such as genomic analysis for identifying specific gene mutations or epigenetic testing of promoter methylation, are already in clinical use, other "omics-based" assays are still evolving. Here, we provide an overview of the current status of molecular profiling methods, including promising research strategies, as well as possible challenges, and their emerging role in radiation oncology.


Assuntos
Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica/métodos , Genômica/métodos , Neoplasias/genética , Neoplasias/radioterapia , Medicina de Precisão/métodos , Radioterapia (Especialidade)/métodos , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Predisposição Genética para Doença , Humanos , Metabolômica/métodos , Neoplasias/metabolismo , Neoplasias/patologia , Seleção de Pacientes , Fenótipo , Valor Preditivo dos Testes , Proteômica/métodos , Tolerância a Radiação/genética , Resultado do Tratamento
19.
Int J Oncol ; 48(1): 313-21, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26549537

RESUMO

Three-dimensional ex vivo cell cultures mimic physiological in vivo growth conditions thereby significantly contributing to our understanding of tumor cell growth and survival, therapy resistance and identification of novel potent cancer targets. In the present study, we describe advanced three-dimensional cell culture methodology for investigating cellular survival and proliferation in human carcinoma cells after cancer therapy including molecular therapeutics. Single cells are embedded into laminin-rich extracellular matrix and can be treated with cytotoxic drugs, ionizing or UV radiation or any other substance of interest when consolidated and approximating in vivo morphology. Subsequently, cells are allowed to grow for automated determination of clonogenic survival (colony number) or proliferation (colony size). The entire protocol of 3D cell plating takes ~1 h working time and pursues for ~7 days before evaluation. This newly developed method broadens the spectrum of exploration of malignant tumors and other diseases and enables the obtainment of more reliable data on cancer treatment efficacy.


Assuntos
Técnicas de Cultura de Células/métodos , Proliferação de Células , Sobrevivência Celular , Carcinoma/tratamento farmacológico , Carcinoma/patologia , Carcinoma/radioterapia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/efeitos da radiação , Humanos , Laminina/química
20.
J Biol Methods ; 2(4)2015.
Artigo em Inglês | MEDLINE | ID: mdl-26618185

RESUMO

Analysis of signal transduction and protein phosphorylation is fundamental to understanding physiological and pathological cell behavior and identifying novel therapeutic targets. Despite the fact that the use of physiological three-dimensional cell culture assays is increasing, 3D proteomics and phosphoproteomics remain challenging due to difficulties with easy, robust and reproducible sample preparation. Here, we present an easy-to-perform, reliable and time-efficient method for the production of 3D cell lysates that does not compromise cell adhesion before cell lysis. The samples can be used for western blotting as well as phosphoproteome array technology. This technique will be of interest for researchers working in all fields of biology and drug development.

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