Browsing by Subject "radiation therapy"

Now showing 1 - 5 of 5
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    Dichotomous effects of cellular expression of STAT3 on tumor growth of HNSCC
    (Elsevier, 2021) Bickett, Thomas E.; Knitz, Michael W.; Piper, Miles; Oweida, Ayman J.; Gadwa, Jacob; Darragh, Laurel B.; Nguyen, Diemmy; Bhatia, Shilpa; Bhuvane, Shiv; Phan, Andy V.; Van Court, Benjamin; Corbo, Sophia; Pham, Tiffany; Dent, Alexander L.; Lenz, Laurel; Karam, Sana D.; Microbiology and Immunology, School of Medicine
    STAT3 signaling has been shown to regulate cellular function and cytokine production in the tumor microenvironment (TME). Within the head and neck squamous cell carcinoma (HNSCC) TME, we previously showed that therapeutic targeting of STAT3 in combination with radiation resulted in improved tumor growth delay. However, given the independent regulatory effects STAT3 has on anti-tumor immunity, we aimed to decipher the effects of individually targeting STAT3 in the cancer cell, regulatory T cells (Tregs), and natural killer (NK) cell compartments in driving tumor growth and resistance to therapy in HNSCCs. We utilized a CRISPR knockout system for genetic deletion of STAT3 within the cancer cell as well as two genetic knockout mouse models, FoxP3-Cre/STAT3 fl and NKp46-Cre/STAT3 fl, for Tregs and NK cell targeting, respectively. Our data revealed differences in development of resistance to treatment with STAT3 CRISPR knockout in the cancer cell, driven by differential recruitment of immune cells. Knockout of STAT3 in Tregs overcomes this resistance and results in Treg reprogramming and recruitment and activation of antigen-presenting cells. In contrast, knockout of STAT3 in the NK cell compartment results in NK cell inactivation and acceleration of tumor growth. These data underscore the complex interplay between the cancer cell and the immune TME and carry significant implications for drug targeting and design of combination approaches in HNSCCs.
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    Early Cardiac Effects of Contemporary Radiation Therapy in Patients With Breast Cancer
    (Elsevier, 2020) Clasen, Suparna C.; Shou, Haochang; Freedman, Gary; Plastaras, John P.; Taunk, Neil K.; Teo, Boon-Keng Kevin; Smith, Amanda M.; Demissei, Biniyam G.; Ky, Bonnie; Medicine, School of Medicine
    Purpose To characterize the early changes in echocardiographically derived measures of cardiac function with contemporary radiation therapy (RT) in breast cancer and to determine the associations with radiation dose-volume metrics, including mean heart dose (MHD). Methods and Materials In a prospective longitudinal cohort study of 86 patients with breast cancer treated with photon or proton thoracic RT, clinical and echocardiographic data were assessed at 3 time points: within 4 weeks before RT initiation (T0), within 3 days before 6 weeks after the end of RT (T1), and 5 to 9 months after RT completion (T2). Associations between MHD and echocardiographically derived measures of cardiac function were assessed using generalized estimating equations to define the acute (T0 to T1) and subacute (T0 to T2) changes in cardiac function. Results The median estimates of MHD were 139 cGy (interquartile range, 99-249 cGy). In evaluating the acute changes in left ventricular ejection fraction (LVEF) from T0 to T1, and accounting for the time from RT, age, race, preexisting cardiovascular disease, and an interaction term with anthracycline or trastuzumab exposure and MHD, there was a modest decrease in LVEF of borderline significance (0.22%; 95% confidence interval [CI], –0.44% to 0.01%; P = .06) per 30-day interval for every 100 cGy increase of MHD. Similarly, there was a modest worsening in longitudinal strain (0.19%; 95% CI, –0.01% to 0.39%; P = .06) per 30-day interval for each 100 cGy increase in MHD. We did not find significant associations between MHD and changes in circumferential strain or diastolic function. Conclusions With modern radiation planning techniques, there are modest subclinical changes in measures of cardiac function in the short-term. Longer-term follow-up studies are needed to determine whether these early changes are associated with the development of overt cardiac disease.
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    Literature review of management of brain metastases from germ cell tumors
    (AME, 2022-04-30) Le , Amy; Arbab , Mona; Adra , Nabil; Miller , James C.; Watson , Gordon A.; Shiue, Kevin; Radiation Oncology, School of Medicine
    Objective: In this review article, we discuss the role of chemotherapy, surgery, and radiation therapy in the treatment of brain metastases from germ cell tumors (GCT). Background: GCT rarely metastasize to the brain and there is limited data to guide management. Most instances of brain metastases occur in patients with non-seminomatous germ cell tumors (NSGCT). Methods: We searched PubMed using the terms 'central nervous system (CNS) metastases' or 'brain metastases' and 'germ cell' from 2011 through August 2021. Review articles and prospective trials related to the treatment of brain metastases in GCT were included in addition to articles obtained by hand search of the references and clinical practice guidelines. Conclusions: We highlight the importance of using chemotherapy as first-line therapy in most situations. We discuss the very minimal data regarding surgery and its primary role when there is significant mass effect or brain shift. We also compare whole brain radiation therapy (WBRT) with the use of radiosurgery. We then provide overall recommendations based on the reviewed data and our experience as a referral center for GCT.
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    Mifepristone as Bridge or Adjunct Therapy in the Management of Challenging Cushing Disease Cases
    (Sage, 2021) Chang, Alice Y.; Mirfakhraee, Sasan; King, Elizabeth E.; Mercado, Jennifer U.; Donegan, Diane M.; Yuen, Kevin C. J.; Medicine, School of Medicine
    Establishing a definitive diagnosis of Cushing disease (CD), given its clinical and biochemical heterogeneity, initiating effective treatment to control the effects of hypercortisolism, and managing recurrence are challenging disease aspects to address. Mifepristone is a competitive glucocorticoid receptor antagonist that is approved in the US by the Food and Drug Administration to control hyperglycemia secondary to endogenous hypercortisolism (Cushing syndrome) in patients who have glucose intolerance or type 2 diabetes mellitus and have failed surgery or are not candidates for surgery. Herein, we describe 6 patients with CD who received mifepristone as adjunct/bridge therapy in the following clinical settings: to assess clinical benefits of treatment for suspected recurrent disease, to control hypercortisolism preoperatively for severe disease, to control hypercortisolism during the COVID-19 pandemic, and to provide adjunctive treatment to radiation therapy. The patients were treated at multiple medical practice settings. Mifepristone treatment in each of the described cases was associated with clinical improvements, including improvements in overall glycemia, hypertension, and weight loss. In addition, in one case where biochemical and radiological evidence of disease recurrence was uncertain, clinical improvement with mifepristone pointed toward likely disease recurrence. Adverse events associated with mifepristone reported in the 6 cases were consistent with those previously reported in the pivotal trial and included cortisol withdrawal symptoms, antiprogesterone effects (vaginal bleeding), hypothyroidism (treated with levothyroxine), and hypokalemia (treated with spironolactone). These cases show how mifepristone can potentially be utilized as a therapeutic trial in equivocal cases of CD recurrence; as a presurgical treatment strategy, particularly during the COVID-19 pandemic; and as bridge therapy, while awaiting the effects of radiation.
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    The Sin of Exclusion: Applicability of Trials Encouraging Omission of Radiation Therapy to Nonwhite Patients With Breast Cancer
    (ASCO, 2018-11) McClelland, Shearwood, III; Xanthopoulos, Eric P.; Mitin, Timur; Graduate Medical Education, School of Medicine