Browsing by Subject "Radiation"
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Item 142. Optimization of the Murine Hindlimb Lymphedema Model(Wolters Kluwer, 2025-04-24) Ahmed, Shahnur; Mohan, Ganesh; Sullivan, Steven J.; Jorge, Miguel; Sinha, Mithun; Hassanein, Aladdin H.; Surgery, School of MedicinePURPOSE: Secondary lymphedema is limb swelling from lymphatic injury. It frequently occurs following lymph node dissection and radiation during the treatment of malignancies such as breast cancer or melanoma. The murine tail is the most commonly used model to study secondary lymphedema and involves full thickness tail skin excision and lymphatic vessel disruption. The murine hindlimb model, which has been less frequently used in the literature, offers a more clinically translatable method. However, there is inconsistency and variability, including the benefit of radiation, which have contributed to the model being less widely adapted than the tail model. The purpose of this study is to 1) optimize the murine hindlimb lymphedema to achieve consistent results and 2) assess the effect of radiation on outcome in the murine hindlimb model. METHODS: C57BL/6 mice either underwent 20 Gy irradiation of one hindlimb seven days prior to surgery (n=11) or no preoperative radiation (n=9). For all mice, a circumferential skin incision was created at the proximal hindlimb exposing the subcutaneous soft tissues. Lymphatics were identified with isosulfan blue dye injection into the paw and disrupted. Popliteal lymph nodes were excised. The skin was sutured leaving a 3 mm gap. The contralateral hindlimb served as the control. Paw thickness and calf thickness measurements were obtained at weekly intervals and indocyanine green (ICG) near-infrared laser lymphangiography was used to assess lymphatic function. RESULTS: For the irradiated mice, the average paw thickness of the operated hindlimb on postoperative day (POD) 14 was 3.5±0.3 cm compared to 2.1±0.05 cm on the contralateral limb (p=0.0001). At POD-90, the average paw thickness of the irradiated, operated hindlimb was 2.4±0.1 cm compared to 2.1±0.1 cm for the contralateral limb (p=0.01). ICG lymphangiography at 24-hours postinjection on POD-42 demonstrated an average signal intensity of 97.7±28.5 arbitrary fluorescent units (AFU) in the operated hindlimb compared to 33.6±6.2 AFU in the non-operated hindlimb (p=0.003). In the mice that did not undergo radiation, the average paw thickness was 2.5±0.2 cm on POD-42 was greater than the contralateral limb (2.1±0.1 cm) (p=0.0002) but smaller than hindlimbs that underwent radiation (3.2±0.1 cm) (p=0.0002). The nonradiated mice had greater paw thickness than the contralateral control until POD-56 whereas the radiated mice sustained significant paw thickness until Day 90. CONCLUSION: Radiation of the murine hindlimb model results in sustained lymphedema compared to non-irradiated mice. The murine hindlimb lymphedema model is clinically more translatable than the murine tail model and includes limb lymphatic vessel disruption, and popliteal lymphadenectomy and ideally radiation for consistent results with lymphedema sustained for 90 days.Item Changes in receipt of adjuvant brachytherapy for endometrial cancer patients before and after affordable care act: The impact of Medicaid expansion(Termedia Publishing, 2023) Le, Amy; Holmes, Jordan A.; Radiation Oncology, School of MedicinePurpose: For patients with high-intermediate risk (HIR) endometrial cancer, adjuvant radiation (RT) reduces the risk of recurrence, but many patients do not receive RT. Under the Affordable Care Act (ACA), most states expanded Medicaid coverage. Our hypothesis was patients would be more likely to receive indicated adjuvant RT in states that expanded Medicaid compared with patients in states that did not expand Medicaid. Material and methods: National Cancer Database (NCDB) was used to identify patients aged 40-64 years with HIR endometrial adenocarcinoma, stage IA and grade 3 or stage IB and grade 1 or 2, diagnosed from 2010-2018. We conducted a difference-in-differences (DID) cross-sectional retrospective analysis comparing receipt of adjuvant RT among patients residing in Medicaid expansion and non-expansion states before and after ACA implementation (January 2014). Results: Expansion states had higher rates of adjuvant RT prior to January 2014 compared with non-expansion states (49.21% vs. 36.46%), and the proportion of patients who received adjuvant RT increased over the study period across both Medicaid expansion and non-expansion states. After Medicaid expansion, the non-expansion states had a larger absolute increase in adjuvant radiation resulting in a non-significant change in the difference in adjuvant radiation rates compared with baseline (crude increase: 9.63% vs. 7.45%, adjusted DID: -2.68 [95% CI: -7.12-1.75], p = 0.236). Conclusions: Medicaid expansion is likely not the most significant factor affecting access or receipt of adjuvant RT for HIR endometrial cancer patients. Further study could help inform policy and efforts to ensure all patients have access to guideline-recommended RT.Item Clinical and Genetic Risk Factors for Radiation-Associated Ototoxicity: A Report from the Childhood Cancer Survivor Study and the St. Jude Lifetime Cohort(Wiley, 2021) Trendowski, Matthew R.; Baedke, Jessica L.; Sapkota, Yadav; Travis, Lois B.; Zhang, Xindi; El Charif, Omar; Wheeler, Heather E.; Leisenring, Wendy M.; Robison, Leslie L.; Hudson, Melissa M.; Morton, Lindsay M.; Oeffinger, Kevin C.; Howell, Rebecca M.; Armstrong, Gregory T.; Bhatia, Smita; Dolan, M. Eileen; Epidemiology, School of Public HealthBackground: Cranial radiation therapy (CRT) is associated with ototoxicity, which manifests as hearing loss and tinnitus. The authors sought to identify clinical determinants and genetic risk factors for ototoxicity among adult survivors of pediatric cancer treated with CRT. Methods: Logistic regression evaluated associations of tinnitus (n = 1991) and hearing loss (n = 2198) with nongenetic risk factors and comorbidities among CRT-treated survivors in the Childhood Cancer Survivor Study. Genome-wide association studies (GWASs) of CRT-related tinnitus and hearing loss were also performed. Results: Males were more likely to report CRT-related tinnitus (9.4% vs 5.4%; P = 5.1 × 10-4 ) and hearing loss (14.0% vs 10.7%; P = .02) than females. Survivors with tinnitus or hearing loss were more likely to experience persistent dizziness or vertigo (tinnitus: P < 2 × 10-16 ; hearing loss: P = 6.4 × 10-9 ), take antidepressants (tinnitus: P = .02; hearing loss: P = .01), and report poorer overall health (tinnitus: P = 1.5 × 10-6 ; hearing loss: P = 1.7 × 10-6 ) in comparison with controls. GWAS of CRT-related tinnitus revealed a genome-wide significant signal in chromosome 1 led by rs203248 (P = 1.5 × 10-9 ), whereas GWAS of CRT-related hearing loss identified rs332013 (P = 5.8 × 10-7 ) in chromosome 8 and rs67522722 (P = 7.8 × 10-7 ) in chromosome 6 as nearly genome-wide significant. A replication analysis identified rs67522722, intronic to ATXN1, as being significantly associated with CRT-related hearing loss (P = .03) and de novo hearing loss (P = 3.6 × 10-4 ). Conclusions: CRT-associated ototoxicity was associated with sex, several neuro-otological symptoms, increased antidepressant use, and poorer self-reported health. GWAS of CRT-related hearing loss identified rs67522722, which was supported in an independent cohort of survivors. Lay summary: Hearing loss and subjective tinnitus (the perception of noise or ringing in the ear) are long-term side effects of cancer treatment and are common in children treated with radiation to the brain. These toxicities can affect childhood development and potentially contribute to serious learning and behavioral difficulties. This study's data indicate that males are at greater risk for hearing loss and tinnitus than females after radiation therapy to the brain. Those who develop these toxicities are more likely to use antidepressants and report poorer overall health. Health care providers can improve the management of survivors by informing patients and/or their parents of these risks.Item Comparative Survival Benefits of Surgery and Adjuvant Chemotherapy in Neuroendocrine Carcinoma of the Gallbladder: A Population-Based Study with Insight into Future Personalized Therapeutic Approach(MDPI, 2023-06-18) Khan, Jaffar; Ullah, Asad; Yasinzai, Abdul Qahar Khan; Waheed, Abdul; Ballur, Kalyani; Dickerson, Thomas E.; Ullah, Kaleem; Mejias, Christopher D.; Saeed, Omer; Pathology and Laboratory Medicine, School of MedicineBackground: Neuroendocrine carcinomas of the gallbladder (NECs-GB) are rare tumors, accounting for <0.2% of all neuroendocrine carcinomas of the gastrointestinal tract. They originate from the neuroendocrine cells of the gallbladder epithelium with associated intestinal or gastric metaplasia. The current study is the largest study from the SEER database on NECs-GB that aims to elucidate the demographic, clinical, and pathologic factors influencing the prognosis and comparative survival analysis of different treatment modalities. Methods: The data from 176 patients with NECs-GB was abstracted from the Surveillance Epidemiology and End Result (SEER) database (2000–2018). Multivariate analysis, non-parametric survival analysis, and a chi-square test were used to analyze the data. Results: NECs-GB had a higher incidence amongst females (72.7%) and Caucasians (72.7%). Most patients had surgery only (N = 52, 29.5%), (N = 40) 22.7% had chemotherapy only, and (N = 23) 13.1% had chemotherapy with surgery. Only (N = 17) 9.7% had trimodaltiy (surgery, chemotherapy, and radiation therapy), and for (N = 41) 23.3% the status of chemotherapy was unknown, and these cases had neither radiation nor surgery. Conclusion: NECs-GB more frequently affects Caucasian females after the 6th decade of life. The combination of surgery, radiation, and adjuvant chemotherapy was associated with better long-term (5 years) outcomes, while surgery alone was associated with better short-term (<2 years) outcome survival.Item Corrigendum: eIF3a Regulation of NHEJ Repair Protein Synthesis and Cellular Response to Ionizing Radiation(Frontiers Media, 2021-01-07) Tumia, Rima; Wang, Chao J.; Dong, Tianhan; Ma, Shijie; Beebe, Jenny; Chen, Juan; Dong, Zizheng; Liu, Jing-Yuan; Zhang, Jian-Ting; Pharmacology and Toxicology, School of Medicine[This corrects the article DOI: 10.3389/fcell.2020.00753.].Item Editorial: Ongoing advancements in the research of radiation- induced toxicity and the development of interventions to protect and/or mitigate its effects(Frontiers Media, 2024-08-21) Cui, Wanchang; Plett, P. Artur; Sharma, Guru Prasad; Kerns, Sarah; MacVittie, Thomas J.; Medicine, School of MedicineItem The Exploration of an Effective Medical Countermeasure Enhancing Survival and Hematopoietic Recovery and Preventing Immune Insufficiency in Lethally-Irradiated Mice(2020-08) Wu, Tong; Orschell, Christie M.; Basile, David P.; Unthank, Joseph L.; Haneline, Laura S.; Pelus, Louis M.; MacVittie, Thomas J.There is an urgent demand for effective medical countermeasures (MCM) in the event of high-dose radiation exposure ranging from nuclear plant disasters to potential nuclear warfare. Victims of lethal-dose radiation exposure face multi-organ injuries including the hematopoietic acute radiation syndrome (H-ARS) and the delayed effects of acute radiation exposure (DEARE) years after irradiation. Defective lymphocyte reconstitution and its subsequent immune insufficiency are some of the most serious consequences of H-ARS and DEARE. In order to investigate potential MCMs to protect or mitigate these radiation injuries, the prolonged tissue-specific immunosuppression at all levels of lymphocyte development in established murine H-ARS and DEARE models was defined, along with unique sex-related and age-related changes present in some tissues but not others. The “double hits” of irradiation and age-related stress on lymphopoiesis led to significant myeloid skew and long-term immune involution. Different kinds and different combinations of hematopoietic growth factors, some in combination with angiotensin converting enzyme inhibitor, were administered to lethally irradiated mice. These radiomitigators were found to significantly increase survival and enhance hematopoiesis in H-ARS, but they did little to alleviate the severity of DEARE including immune insufficiency. 16,16 dimethyl-prostaglandin E2 (dmPGE2), a long-acting formulation of PGE2 with similar biological effects as PGE2, was found to enhance survival and hematopoiesis in lethal-irradiated mice when used as radiomitigator or radioprotectant. The optimum time window for administration of radioprotectant and radiomitigator dmPGE2 was defined, which is -3hr to -15min prior to irradiation and +6hr to +30hr post irradiation. Significant survival efficacy of radioprotectant dmPGE2 was also demonstrated in pediatric and geriatric mice. Using specific PGE2 receptor (EP) agonists, the EP4 receptor was defined as the PGE2 receptor potentially responsible for dmPGE2 radioprotection. Radioprotectant dmPGE2 was also found to prevent radiation-induced thymic involution and to ameliorate the long-term immune suppression in radiation survivors in the DEARE phase via promoting hematopoietic stem cell differentiation towards to the lymphoid lineage. This is the first report of an effective MCM for H-ARS which also targets long-term thymic involution and lymphoid lineage reconstitution.Item Innate Immune Pathways Associated with Lung Radioprotection by Soy Isoflavones(Frontiers, 2017-01-23) Abernathy, Lisa M.; Fountain, Matthew D.; Joiner, Michael C.; Hillman, Gilda G.; Department of Microbiology & Immunology, IU School of MedicineINTRODUCTION: Radiation therapy for lung cancer causes pneumonitis and fibrosis. Soy isoflavones protect against radiation-induced lung injury, but the mediators of radioprotection remain unclear. We investigated the effect of radiation on myeloid-derived suppressor cells (MDSCs) in the lung and their modulation by soy isoflavones for a potential role in protection from radiation-induced lung injury. METHODS: BALB/c mice (5-6 weeks old) received a single 10 Gy dose of thoracic irradiation and soy isoflavones were orally administrated daily before and after radiation at 1 mg/day. Arginase-1 (Arg-1) and nuclear factor κB (NF-κB) p65 were detected in lung tissue by western blot analysis and immunohistochemistry. Lung MDSC subsets and their Arg-1 expression were analyzed by flow cytometry. Cytokine levels in the lungs were measured by ELISA. RESULTS: At 1 week after radiation, CD11b+ cells expressing Arg-1 were decreased by radiation in lung tissue yet maintained in the lungs treated with radiation and soy isoflavones. Arg-1 was predominantly expressed by CD11b+Ly6ClowLy6G+ granulocytic MDSCs (gr-MDSCs). Arg-1 expression in gr-MDSCs was reduced by radiation and preserved by supplementation with soy isoflavones. A persistent increase in Arg-1+ cells was observed in lung tissue treated with combined radiation and soy isoflavones at early and late time points, compared to radiation alone. The increase in Arg-1 expression mediated by soy isoflavones could be associated with the inhibition of radiation-induced activation of NF-κB and the control of pro-inflammatory cytokine production demonstrated in this study. CONCLUSION: A radioprotective mechanism of soy isoflavones may involve the promotion of Arg-1-expressing gr-MDSCs that could play a role in downregulation of inflammation and lung radioprotection.Item Irradiation of Nf1 mutant mouse models of spinal plexiform neurofibromas drives pathologic progression and decreases survival(Oxford University Press, 2021-04-23) Laurent, Danny; Smith, Abbi E.; Bessler, Waylan K.; Mendonca, Marc; Chin-Sinex, Helen; Descovich, Martina; Horvai, Andrew E.; Clapp, D. Wade; Nakamura, Jean L.; Radiation Oncology, School of MedicineBackground: Genetically susceptible individuals can develop malignancies after irradiation of normal tissues. In the context of therapeutic irradiation, it is not known whether irradiating benign neoplasms in susceptible individuals promotes neoplastic transformation and worse clinical outcomes. Individuals with Neurofibromatosis 1 (NF1) are susceptible to both radiation-induced second malignancies and spontaneous progression of plexiform neurofibromas (PNs) to malignant peripheral nerve sheath tumors (MPNSTs). The role of radiotherapy in the treatment of benign neoplasms such as PNs is unclear. Methods: To test whether radiotherapy promotes neoplastic progression of PNs and reduces overall survival, we administered spinal irradiation (SI) to conditional knockout mouse models of NF1-associated PNs in 2 germline contexts: Nf1 fllfl ; PostnCre + and Nf1 fl/- ; PostnCre + . Both genotypes develop extensive Nf1 null spinal PNs, modeling PNs in NF1 patients. A total of 101 mice were randomized to 0 Gy, 15 Gy (3 Gy × 5), or 30 Gy (3 Gy × 10) of spine-focused, fractionated SI and aged until signs of illness. Results: SI decreased survival in both Nf1 fllfl mice and Nf1 fl/- mice, with the worst overall survival occurring in Nf1 fl/- mice receiving 30 Gy. SI was also associated with increasing worrisome histologic features along the PN-MPNST continuum in PNs irradiated to higher radiation doses. Conclusions: This preclinical study provides experimental evidence that irradiation of pre-existing PNs reduces survival and may shift PNs to higher grade neoplasms.Item Local and distant brain control in melanoma and NSCLC brain metastases with concurrent radiosurgery and immune checkpoint inhibition(Springer, 2022-07) Le, Amy; Mohammadi, Homan; Mohammed, Toka; Burney, Heather; Zang, Yong; Frye, Douglas; Shiue, Kevin; Lautenschlaeger, Tim; Miller, James; Radiation Oncology, School of MedicineIntroduction The treatment of brain metastases with stereotactic radiosurgery (SRS) in combination with immune checkpoint inhibitors (ICI) has become more common in recent years, but there is a lack of prospective data on cancer control outcomes when these therapies are administered concurrently. Methods Data were retrospectively reviewed for patients with non-small cell lung cancer (NSCLC) and melanoma brain metastases treated with SRS at a single institution from May 2008 to January 2017. A parametric proportional hazard model is used to detect the effect of concurrent ICI within 30, 60, or 90 days of ICI administration on local control and distant in-brain control. Other patient and lesion characteristics are treated as covariates and adjusted in the regression. A frailty term is added in the baseline hazard to capture the within-patient correlation. Results We identified 144 patients with 477 total lesions, including 95 NSCLC patients (66.0%), and 49 (34.0%) melanoma patients. On multivariate analysis, concurrent SRS and ICI (SRS within 30 days of ICI administration) was not associated with local control but was associated with distant brain control. When controlling for prior treatment to lesion, number of lesions, and presence of extracranial metastases, patients receiving this combination had a statistically significant decrease in distant brain failure compared to patients that received non-concurrent ICI or no ICI (HR 0.15; 95% CI 0.05–0.47, p = 0.0011). Conclusion Concurrent ICI can enhance the efficacy of SRS. Prospective studies would allow for stronger evidence to support the impact of concurrent SRS and ICI on disease outcomes.