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ItemModifiable Lifestyle Factors Associated With Response to Treatment in Early Rheumatoid Arthritis(WILEY, 2020-06)OBJECTIVE: We aimed to evaluate the associations between response to algorithm-directed treat-to-target conventional synthetic disease-modifying antirheumatic drug therapy and potentially modifiable lifestyle factors, including dietary fish oil supplementation, body mass index (BMI), and smoking history in a rheumatoid arthritis (RA) inception cohort. METHODS: Patients with RA with a duration of less than 12 months were reviewed every 3 to 6 weeks to adjust therapy according to disease response. All patients received advice to take fish oil supplements, and omega-3 status was measured as plasma levels of eicosapentaenoic acid (EPA). Lifestyle factors and other variables potentially prognostic for 28-joint Disease Activity Score (DAS28) remission and DAS28 low disease activity (LDA) at the 12-month visit were included in multivariable logistic regression models. RESULTS: Of 300 participants, 57.7% reached DAS28 LDA, and 43.7% were in DAS28 remission at 1 year. Increase in plasma EPA was associated with an increase in the odds of being in LDA (adjusted odds ratio [OR] = 1.27; P < 0.0001) and remission (adjusted OR = 1.21; P < 0.001). There was some evidence that the effect of BMI on LDA might be modified by smoking history. An increase in BMI was associated with a decrease in the odds of being in LDA in current and former smokers but had no impact on LDA in patients who had never smoked. There were no meaningful associations between BMI or smoking history and remission. CONCLUSION: Omega-3 status, BMI, and smoking history are potential predictors of outcome in early RA. The possibility of an effect modification by smoking on the predictive value of BMI merits further investigation.
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ItemNo Preview AvailableIntegrating Shared Survivorship Care into an Allogeneic Bone Marrow Transplant Long Term Follow up Service(ELSEVIER SCIENCE INC, 2020-03)
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ItemSUN-127 Diagnostic Challenges Associated with the Rising Incidence of Endocrine Toxicity in the Era of Combination Immunotherapy(The Endocrine Society, 2020-05-08)Abstract Background: Immune checkpoint blockade is now established as standard of care in several malignancies. Trials involving combined cytotoxic T lymphocyte associated protein 4 (CTLA4) and programmed cell death protein 1 (PD1) blockade demonstrate improved tumour responses in melanoma but at the cost of severe grade 3-4 immune related adverse events (irAEs) in 55%, and endocrine irAEs in up to 10% [1]. Immune-mediated damage to endocrine glands can be a diagnostic and management challenge. We aimed to review the incidence, biochemical evolution and imaging findings of endocrine toxicity related to combined anti CTLA-4 and anti-PD-1 therapy. Methods: We undertook a retrospective chart review of patients who received combined ipilimumab and nivolumab for metastatic melanoma at a tertiary referral centre between 2016-2019. We recorded onset and duration of abnormal biochemistry in endocrine irAEs, reviewed all available MRI images for pituitary size (mm) and appearance and 18-F FDG PET images for features of hypophysitis, thyroiditis and pancreatitis. Results: 162 patients received combination therapy. At least one irAE was recorded in 135 patients (83%), 100 (62%) required glucocorticoids, and 84 (52%) had an unplanned hospital presentation due to irAEs. Thyroiditis occurred in 50 (30.9%), with median time to onset of 30.9 days (range 1-234 days). 35 cases were identified with routine biochemistry performed every 4-6 weeks. TSH receptor antibody was measured in 13 patients and all were negative. 29 (58%) developed permanent hypothyroidism. Central cortisol deficiency was documented in 31 (19%) with a median time to diagnosis of 67.5 days (range 5-286). 4 cases were diagnosed on routine biochemistry and 14 presented with symptoms prompting investigation. 13 were diagnosed after routine neuroimaging demonstrated a pituitary abnormality, and a further 27 patients without the clinical syndrome had features of hypophysitis on neuroimaging. New onset diabetes occurred in 3 people, in which pancreatic inflammation on imaging was found in 2. A further 3/5 patients with an asymptomatic elevated lipase were found to have abnormal pancreatic imaging. In one patient with no features of endocrine or exocrine failure, there was a significant increase in FDG uptake and a subsequent loss of pancreatic volume. Conclusion: We report real world incidence of endocrine irAEs with combination immunotherapy. Routine biochemistry leads to the detection of some but not all cases. Early recognition and avoidance of unplanned presentations remains a challenge. Opportunistic assessment of endocrine gland appearance on routine imaging studies may provide useful early diagnostic information. Reference: Larkin J, Chiarion-Sileni V, Gonzalez R, Grob JJ, Cowey CL, Lao CD, et al. Combined nivolumab and ipilimumab or monotherapy in untreated melanoma. N Engl J Med. (2015) 1:23-34. 10.1056/NEJMoa1504030
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ItemSUN-039 Estradiol Dose and Concentrations in Transfeminine Individuals(The Endocrine Society, 2020-05)Abstract Background: Feminizing hormone therapy with estradiol is used to align an individual’s physical characteristics with their gender identity. Australian expert consensus guidelines (1) recommend targeting estradiol concentrations of 250-600 pmol/L (68-163 pg/mL) based on local cross-sectional data (2). We aimed to establish the proportion of individuals achieving estradiol concentrations in consensus guidelines. Methods: A retrospective cross-sectional analysis was performed of transfeminine individuals attending a primary or secondary care clinic in Melbourne, Australia who were prescribed oral estradiol valerate for at least 6 months and had estradiol dose and concentration available. Estradiol concentration was measured by immunoassay. Outcomes were (1) proportion of individuals achieving target estradiol concentrations and (2) influence of estradiol dose and BMI on estradiol concentrations. Results: 259 individuals (median age 25.8(IQR 21.9,33.5) years)) had data available for analysis. Median duration of estradiol therapy was 24(15,33) months. Median estradiol concentration was 328(238,434) pmol/L (89(65,118) pg/mL) on 6(4,8) mg estradiol valerate. 172 (66%) individuals had estradiol concentrations within the target range recommended in consensus guidelines. 70 (27%) individuals had estradiol concentrations below target, and 17 (7%) above target. There was a weak positive correlation between estradiol dose and estradiol concentration (r=0.156, p=0.012). There was no correlation between BMI and estradiol concentration achieved (r=-0.063, p=0.413). Conclusions: 66% of individuals achieved estradiol concentration recommended in consensus guidelines with a relatively high oral estradiol dose. There was significant interindividual variability. Estradiol concentration should be interpreted in conjunction with clinical features of feminization and weighed against potential risks of escalating estradiol dose. References 1. Cheung AS, Wynne K, Erasmus J, Murray S, Zajac JD. Position statement on the hormonal management of adult transgender and gender diverse individuals. Med J Aust 2019; 211:127-133 2. Angus L, Leemaqz SY, Ooi O, Cundill P, Silberstein N, Locke P, Zajac JD, Cheung AS. Cyproterone acetate or spironolactone in lowering testosterone concentrations for transgender individuals receiving estradiol therapy. Endocr Connect 2019
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ItemNo Preview AvailableInhibition of RNA polymerase I transcription activates targeted DNA damage response and enhances the efficacy of PARP inhibitors in high-grade serous ovarian cancer.(AMER ASSOC CANCER RESEARCH, 2020-07)Abstract Introduction: PARP inhibitors (PARPi) have revolutionized disease management of patients with homologous recombination (HR) DNA repair-deficient high-grade serous ovarian cancer (HGSOC). However, acquired resistance to PARPi is a major challenge in the clinic. The specific inhibitor of RNA polymerase I (Pol I) transcription of ribosomal RNA genes (rDNA) has demonstrated single-agent antitumor activity in p53 wild-type and p53-mutant hematologic malignancies (first-in-human trial, dose escalation study of CX-5461 at Peter MacCallum Cancer Centre) (Khot et al., Cancer Discov 2019). CX-5461 has also been reported to exhibit synthetic lethality with BRCA1/2 deficiency through stabilization of G-quadruplex DNA (GQ) structures. Here, we investigate the efficacy of CX-5461 in treating HGSOC. Experimental Design: The mechanisms by which CX-5461 induces DNA damage response (DDR) and displays synthetic lethality in HR-deficient HGSOC cells are explored. We present in vivo data of mice bearing two functionally and genomically profiled HGSOC-patient-derived xenograft (PDX)s treated with CX-5461 and olaparib, alone and in combination. We also investigate CX-5461-sensitivity gene expression signatures in primary and relapsed HGSOC. Results: Utilizing ovarian cancer cell lines, we demonstrate that sensitivity to CX-5461 is associated with “BRCA1 mutation” and “MYC targets” gene expression signatures. In addition, sensitivity to CX-5461 is associated with high basal rates of Pol I transcription. Importantly, we demonstrate a novel mechanism for CX-5461 synthetic lethal interaction with HR deficiency mediated through the induction of replication stress at rDNA repeats. Our data reveal CX-5461-mediated DDR in HR-deficient cells does not involve stabilization of GQ structures as previously proposed. On the contrary, we show definitively that CX-5461 inhibits Pol I recruitment leading to rDNA chromatin defects including stabilization of R-loops, single-stranded DNA, and replication stress at the rDNA. Mechanistically, we demonstrate CX-5461 leads to replication-dependent DNA damage involving MRE11-dependent degradation of replication forks. Importantly, CX-5461 has a different sensitivity spectrum to olaparib and cooperates with PARPi in exacerbating replication stress, leading to enhanced therapeutic efficacy in HR-deficient HGSOC-PDX in vivo compared to single-agent treatment of both drugs. Further, CX-5461 exhibits single-agent efficacy in olaparib-resistant HGSOC-PDX overcoming PARPi-resistance mechanisms involving fork protection. Importantly, we identify CX-5461-sensitivity gene expression signatures in primary and relapsed HGSOC. Conclusions: CX-5461 is a promising therapy alone and in combination therapy with PARPi in HR-deficient HGSOC. CX-5461 also has exciting potential as a treatment option for patients with relapsed HGSOC tumors that have high MYC activity and poor clinical outcome; these patients currently have very limited effective treatment options. This abstract is also being presented as Poster A71. Citation Format: Elaine Sanij, Katherine Hannan, Jiachen Xuan, Shunfei Yan, Jessica A. Ahern, Anna S. Trigos, Natalie Brajanovski, Jinbae Son, Keefe T. Chan, Olga Kondrashova, Elizabeth Lieschke, Matthew J. Wakefield, Sarah Ellis, Carleen Cullinane, Gretchen Poortinga, Kum Kum Khanna, Linda Mileshkin, Grant A. McArthur, John Soong, Els M. Berns, Ross D. Hannan, Clare L. Scott, Karen E. Sheppard, Richard B. Pearson. Inhibition of RNA polymerase I transcription activates targeted DNA damage response and enhances the efficacy of PARP inhibitors in high-grade serous ovarian cancer [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research; 2019 Sep 13-16, 2019; Atlanta, GA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(13_Suppl):Abstract nr PR13.