Citations

INTRODUCTION: Opioids are used to treat pain in chronic pancreatitis (CP), but little is known about current use patterns. The aim of this study was to characterize the utilization of opioids and associations with clinical characteristics in adult patients with CP. METHODS: This cross-sectional analysis used baseline data from participants with definite CP enrolled in a cohort study in the United States (PROspective Evaluation of CP for EpidEmiologic and Translational StuDies). Data on demographics, pain medication use, healthcare utilization, disability, and pain patterns were systematically collected in case report forms while quality of life was assessed with patient-reported outcome instruments. Opioid use was classified according to strength (weak or strong) and frequency (scheduled or as-needed). RESULTS: A total of 681 participants (n = 364, 53% male) were included: 299 (44%) were current opioid users (22% only weak opioids and 22% at least 1 strong opioid). Increasing frequency and severity of pain was associated with increase of weak, strong, as-needed, or scheduled opioids. Neuromodulators were used by ∼40% of participants; increasing use was associated with increasing frequency and severity of pain. On multivariate analysis, independent predictors associated with strength and frequency of current opioid use were pain patterns (odds ratios [ORs] 1.84–8.32 and ORs 1.92–8.52, respectively, P < 0.001) and prior celiac plexus block (OR 3.54, 95% confidence intervals 1.82–6.87 and OR 3.42, 95% confidence intervals 1.76–6.64, respectively). Participants using opioids had higher prevalence of disability, healthcare utilization, and poorer quality of life. DISCUSSION: Opioid use in CP is common and associated with increased pain severity and constancy. These data provide foundational estimates for future trials that can elucidate the complex interactions between patient factors, pain, and interventions.

INTRODUCTION: Chronic Pancreatitis Prognosis Score (COPPS) was developed to discriminate disease severity and predict risk for future hospitalizations. In this cohort study, we evaluated if COPPS predicts the likelihood of hospitalization(s) in an American cohort. METHODS: The Chronic Pancreatitis, Diabetes, and Pancreatic Cancer consortium provided data and serum from subjects with chronic pancreatitis (N = 279). COPPS was calculated with baseline data and stratified by severity (low, moderate, and high). Primary endpoints included number and duration of hospitalizations during 12-month follow-up. RESULTS: The mean ± SD COPPS was 8.4 ± 1.6. COPPS correlated with all primary outcomes: hospitalizations for any reason (number: r = 0.15, P = 0.01; duration: r = 0.16, P = 0.01) and pancreas-related hospitalizations (number: r = 0.15, P = 0.02; duration: r = 0.13, P = 0.04). The severity distribution was 13.3% low, 66.0% moderate, and 20.8% high. 37.6% of subjects had ≥1 hospitalization(s) for any reason; 32.2% had ≥1 pancreas-related hospitalizations. All primary outcomes were significantly different between severity groups: hospitalizations for any reason (number, P = 0.004; duration, P = 0.007) and pancreas-related hospitalizations (number, P = 0.02; duration, P = 0.04). The prevalence of continued drinking at follow-up ( P = 0.04) was higher in the low and moderate groups. The prevalence of anxiety at enrollment ( P = 0.02) and follow-up ( P < 0.05) was higher in the moderate and high groups. DISCUSSION: Statistically, COPPS significantly correlated with hospitalization outcomes, but the correlations were weaker than in previous studies, which may be related to the outpatient nature of the PROspective Evaluation of Chronic Pancreatitis for EpidEmiologic and Translational StuDies cohort and lower prevalence of high severity disease. Studies in other prospective cohorts are needed to understand the full utility of COPPS as a potential tool for clinical risk assessment and intervention.

Abstract OBJECTIVE: We sought to define the mechanisms by which purines regulate DNA repair and therapy response. METHODS: Phosphoproteomics was used to identify GTP-dependent (de)phosphorylation events after radiation (RT) and antibodies generated against novel sites. Animal models of glioblastoma (GBM) and normal tissues were used to assess DNA repair and treatment responses in vivo. RESULTS: Pharmacogenomic inhibition of GTP (but not ATP) synthesis sensitized GBM cells to RT by inhibiting the activity of non-homologous end joining, but not homologous recombination. We found a GTP-dependent RT-induced dephosphorylation event on Abl interactor 1 (Abi-1) serine 323 (S323) using phosphoproteomics. We generated a new antibody for p-Abi-1 (S323), validated its specificity, and confirmed that RT causes a GTP-dependent dephosphorylation of Abi-1 (S323). Knockout of Abi-1 slowed RT-induced double-strand break (DSB) repair, and this was rescued by re-expression of dephosphomimetic Abi-1 (S323A) but not phosphomimetic Abi-1 (S323D). Abi-1 canonically binds to G protein Rac1. Expression of constitutively active Rac1 promoted but dominant negative Rac1 blocked the dephosphorylation of Abi-1 (S323) and DSB repair. Knock-down or inhibition of protein phosphatase 5 reversed the GTP- and Rac1-mediated dephosphorylation of Abi-1 and DSB repair. In GBM PDX samples, p-Abi-1 (S323) levels negatively correlated with Rac1 activity and predicted favorable efficacy of genotoxic treatments. In orthotopic GBM mouse models, inhibiting Rac1 enhanced RT responses and suppressed Abi-1 (S323) dephosphorylation. Abi-1 knockout enhanced efficacy of genotoxic treatments and could be rescued by Abi-1 S323A (but not Abi-1 S323D) re-expression. This regulation is generalizable beyond brain cancer, as GTP supplementation promoted DNA repair and p-Abi1 (S323) dephosphorylation in non-malignant cells and protected mice from RT-mediated gastrointestinal injury and bleomycin-induced pulmonary fibrosis. CONCLUSION: The GTP-Rac1-PP5-Abi-1 signaling axis links metabolism and DNA repair. Disrupting this pathway can overcome cancer resistance to genotoxic therapy while augmenting it can mitigate genotoxic injury of normal tissues. Citation Format: Weihua Zhou, Zitong Zhao, Angelica Lin, John Yang, Jie Xu, Kari Wilder-Romans, Annabel Yang, Andrew J. Scott, Jing Li, Sumeet Solanki, Jennifer Speth, Natalie Walker, Ayesha U. Kothari, Yangyang Yao, Erik R. Peterson, Navyateja Korimerla, Christian K. Werner, Jessica Liang, Janna Jacobson, Sravya Palavalasa, Alexandra M Obrien, Ameer L Elaimy, Sean P. Ferris, Shuang G. Zhao, Jann N. Sarkaria, Balázs Győrffy, Shuqun Zhang, Wajd N. Al-Holou, Yoshie Umemura, Meredith A Morgan, Theodore S. Lawrence, Costas A. Lyssiotis, Marc Peters-Golden, Yatrik M. Shah, Daniel R. Wahl. GTP signaling links metabolism, DNA repair, and responses to genotoxic stress [abstract]. In: Proceedings of the AACR Special Conference on Brain Cancer; 2023 Oct 19-22; Minneapolis, Minnesota. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_1):Abstract nr A004.

Abstract OBJECTIVE We sought to define the mechanisms by which purines regulate DNA repair and therapy response. METHODS Phosphoproteomics was used to identify GTP-dependent (de)phosphorylation events after radiation (RT) and antibodies generated against novel sites. Animal models of glioblastoma (GBM) and normal tissues were used to assess DNA repair and treatment responses in vivo. RESULTS Pharmacogenomic inhibition of GTP (but not ATP) synthesis sensitized GBM cells to RT by inhibiting the activity of non-homologous end joining, but not homologous recombination. We found a GTP-dependent RT-induced dephosphorylation event on Abl interactor 1 (Abi-1) serine 323 (S323) using phosphoproteomics. We generated a new antibody for p-Abi-1 (S323), validated its specificity, and confirmed that RT causes a GTP-dependent dephosphorylation of Abi-1 (S323). Knockout of Abi-1 slowed RT-induced double-strand break (DSB) repair, and this was rescued by re-expression of dephosphomimetic Abi-1 (S323A) but not phosphomimetic Abi-1 (S323D). Abi-1 canonically binds to G protein Rac1. Expression of constitutively active Rac1 promoted but dominant negative Rac1 blocked the dephosphorylation of Abi-1 (S323) and DSB repair. Knock-down or inhibition of protein phosphatase 5 reversed the GTP- and Rac1-mediated dephosphorylation of Abi-1 and DSB repair. In GBM PDX samples, p-Abi-1 (S323) levels negatively correlated with Rac1 activity and predicted favorable efficacy of genotoxic treatments. In orthotopic GBM mouse models, inhibiting Rac1 enhanced RT responses and suppressed Abi-1 (S323) dephosphorylation. Abi-1 knockout enhanced efficacy of genotoxic treatments and could be rescued by Abi-1 S323A (but not Abi-1 S323D) re-expression. This regulation is generalizable beyond brain cancer, as GTP supplementation promoted DNA repair and p-Abi1 (S323) dephosphorylation in non-malignant cells and protected mice from RT-mediated gastrointestinal injury and bleomycin-induced pulmonary fibrosis. CONCLUSION The GTP-Rac1-PP5-Abi-1 signaling axis links metabolism and DNA repair. Disrupting this pathway can overcome GBM resistance to genotoxic therapy while augmenting it can mitigate genotoxic injury of normal tissues.

ABSTRACT How cell metabolism regulates DNA repair is incompletely understood. Here, we define a GTP-mediated signaling cascade that links metabolism to DNA repair and has significant therapeutic implications. GTP, but not other nucleotides, regulates the activity of Rac1, a guanine nucleotide-binding protein, which promotes the dephosphorylation of serine 323 on Abl-interactor 1 (Abi-1) by protein phosphatase 5 (PP5). Dephosphorylated Abi-1, a protein previously not known to activate DNA repair, promotes nonhomologous end joining. In patients and mouse models of glioblastoma, Rac1 and dephosphorylated Abi-1 mediate DNA repair and resistance to standard-of-care genotoxic treatments. The GTP–Rac1–PP5–Abi-1 signaling axis is not limited to brain cancer, as GTP supplementation promotes DNA repair and Abi-1-S323 dephosphorylation in nonmalignant cells and protects mouse tissues from genotoxic insult. This unexpected ability of GTP to regulate DNA repair independently of deoxynucleotide pools has important implications for normal physiology and cancer treatment. SIGNIFICANCE: A newly described GTP-dependent signaling axis is an unexpected link between nucleotide metabolism and DNA repair. Disrupting this pathway can overcome cancer resistance to genotoxic therapy while augmenting it can mitigate genotoxic injury of normal tissues. This article is featured in Selected Articles from This Issue, p. 5

Introduction: High-sensitivity cardiac troponin (hs-cTn) assays were first approved for use in the U.S. in 2017. They are the guideline preferred biomarker to evaluate patients with acute chest pain. Few data exist regarding implementation of hs-cTn assays in the U.S. Hypothesis: We hypothesize that use of hs-cTn assays has increased over time and that patients assessed with hs-cTn have a shorter length of stay (LOS) and similar use of cardiac testing. Methods: We examined trends in implementation of hs-cTn assays among participating hospitals in the NCDR Chest Pain MI Registry from 1/1/2019 through 9/30/2021. Excluding STEMI patients, associations between hs-cTn use, in-hospital diagnostic imaging, and patient outcomes were assessed using logistic or negative binomial regression models. Results: Among 550 participating hospitals with 251,000 patients in the registry, implementation of hs-cTn assays increased from 3.3% in Q1, 2019 to 32.6% in Q3, 2021 (P trend <0.0001; Figure ). Implementation was similar by hospital size, type, and geographic location. hs-cTn use was associated with more echocardiography among patients with NSTE-ACS (82% vs. 75%; aOR: 1.43, 95% CI, 1.19-1.73) but not in low-risk chest pain. hs-cTn use was associated with decreased odds of invasive coronary angiography in low-risk patients (3.7% vs. 4.5%; aOR: 0.73, 95% CI, 0.58-0.92) but similar use in NSTE-ACS. There was no association between hs-cTn use and non-invasive stress/CTCA testing. Among NSTE-ACS patients, hs-cTn use was not associated with PCI, CABG, or in-hospital mortality. Use of hs-cTn was associated with shorter LOS (47.6 hours vs. 48 hours; IRR: 0.96, 95% CI, 0.93-0.98). Conclusions: Although implementation of hs-cTn among U.S. hospitals is increasing, most U.S hospitals continue to use less-sensitive troponin assays. hs-cTn use was associated with shorter LOS overall, greater use of echocardiography in NSTE-ACS, and lower use of invasive angiograms in low-risk patients.

AbstractBackgroundGoal directed point of care ultrasound (POCUS) is a bedside tool to assist with clinical diagnosis. We examined the impact of POCUS performed by consulting cardiologist (CC) during initial cardiology consult on clinical management and downstream testing.MethodsSixty‐nine study patients (pts) seen in a general cardiology outpatient clinic of a tertiary center by an expert imaging CC were compared to a control group of 65 pts seen by three different CCs without POCUS during the same time‐period, in whom the first standard echo (SE) was performed after the initial visit.ResultsBaseline characteristics were similar between the two groups for age, cardiac risk factors, and referral diagnoses. Echo findings on POCUS and by SE (mean delay of 17.2 days after visit) in the control group were comparable for RV size and function and for valvular heart disease. More patients with lower LVEF, higher LV filling pressures, new regional wall motion abnormalities, and increased aortic root size were present among POCUS group resulting in greater yield of echo abnormalities. There were more cardiovascular medication changes at the first visit (15.3% vs. 5.7%, p < .01), less referral for noninvasive stress testing (10% vs. 29%, p < .01), more advanced cardiac testing and subspecialty referrals (29% vs. 18% pts, p = .06), in the study compared to the control group after cardiology visit.ConclusionPOCUS at time of consultation detects more abnormal echo findings, results in more medication adjustments, less referral for noninvasive stress testing, earlier referral for advanced cardiac diagnostic imaging, and subspecialty cardiac referrals.

Abstract Introduction/Objectives: Purines regulate DNA repair in brain tumors through uncertain mechanisms. We sought to define the mechanisms by which purines regulate DNA repair and therapy response. Methods: Crispr/Cas9, siRNA, and CDNA overexpression and immunoblot were used to modulate and confirm protein levels. γ-H2AX and Rad51 foci were enumerated using immunofluorescence. Fluorescent reporter assays were performed to detect DNA repair activity. Phosphoproteomics was used to identify GTP-dependent (de)phosphorylation events after RT and antibodies generated against novel sites. Celltiter-glo or clonogenic assay were performed to evaluate drug/RT responses. IHC was used to detect protein expression. Animal models of glioblastoma and normal tissue (irradiation of GI system) were used to assess DNA repair and treatment responses in vivo. Results: Pharmacogenomic inhibition of GTP (but not ATP) synthesis sensitized GBM cells to RT, slowed the repair of RT-induced DSBs and inhibited the activity of non-homologous end joining (NHEJ), but not homologous recombination (HR). These effects could be rescued by GTP (but not ATP) supplementation. We found a GTP-dependent RT-induced dephosphorylation event on Abl interactor 1 (Abi-1) serine 323 (S323) using phosphoproteomics. We generated a new antibody for p-Abi-1 (S323), validated its specificity, and confirmed that RT causes a GTP-dependent dephosphorylation of Abi-1 (S323). Knockout of Abi-1 slowed RT-induced DSB repair and this was rescued by re-expression of dephosphomimetic Abi-1 (S323A) but not phosphomimetic Abi-1 (S323D). Abi-1 canonically binds to the small GTP-activated protein Rac1. Expression of constitutively active Rac1 promoted the dephosphorylation of Abi-1 (S323) and DSB repair while these effects were blocked by dominant negative Rac1. Pharmacogenomic inhibition of protein phosphatase 5 reversed the GTP- and Rac1-mediated dephosphorylation of Abi-1 and DSB repair. These findings have therapeutic relevance. In GBM PDX samples, levels of p-Abi-1 (S323) negatively correlated with Rac1 activity and predicted favorable efficacy of genotoxic treatments. In orthotopic GBM mouse models, inhibition of Rac1 enhanced RT responses and suppressed Abi-1 S323 dephosphorylation. Abi-1 knockout enhanced efficacy of numerous genotoxic treatments and could be rescued by Abi-1 S323A (but not Abi-1 S323D) re-expression. This regulation is generalizable beyond brain cancer, as GTP supplementation promoted DNA repair and p-Abi1 (S323) dephosphorylation in normal astrocytes and enteroids and protected mice from RT-mediated gastrointestinal injury. Conclusions: GTP promotes DNA repair by activating Rac1 and PP5 to dephosphorylate Abi-1 and stimulate NHEJ. Disrupting this regulation could improve brain tumor treatment responses while augmenting it could help protect normal tissues from genotoxic injury. Citation Format: Weihua Zhou, Angelica Lin, Zitong Zhao, John Yang, Kari Wilder-Romans, Jie Xu, Sumeet Solanki, Jing Li, Annabel Yang, Andrew Scott, Ayesha Kothari, Erik Peterson, Navyateja Korimerla, Jessica Liang, Janna Jacobson, Sravya Palavalasa, Alexandra Obrien, Sean Ferris, Shuang Zhao, Jann N. Sarkaria, Meredith Morgan, Theodore S. Lawrence, Costas A. Lyssiotis, Yatrik Shah, Daniel R. Wahl. GTP-dependent signaling links metabolism, non-homologous end joining and treatment responses in cancer and normal tissues [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3498.

Abstract Purpose: Men with metastatic castration-resistant prostate cancer (mCRPC) frequently develop resistance to androgen receptor signaling inhibitor (ARSI) treatment; therefore, new therapies are needed. Trophoblastic cell-surface antigen (TROP-2) is a transmembrane protein identified in prostate cancer and overexpressed in multiple malignancies. TROP-2 is a therapeutic target for antibody–drug conjugates (ADC). Experimental Design: TROP-2 gene (TACSTD2) expression and markers of treatment resistance from prostate biopsies were analyzed using data from four previously curated cohorts of mCRPC (n = 634) and the PROMOTE study (dbGaP accession phs001141.v1.p1, n = 88). EPCAM or TROP-2–positive circulating tumor cells (CTC) were captured from peripheral blood for comparison of protein (n = 15) and gene expression signatures of treatment resistance (n = 40). We assessed the efficacy of TROP-2–targeting agents in a mouse xenograft model generated from prostate cancer cell lines. Results: We demonstrated that TACSTD2 is expressed in mCRPC from luminal and basal tumors but at lower levels in patients with neuroendocrine prostate cancer. Patients previously treated with ARSI showed no significant difference in TACSTD2 expression, whereas patients with detectable AR-V7 expression showed increased expression. We observed that TROP-2 can serve as a cell surface target for isolating CTCs, which may serve as a predictive biomarker for ADCs. We also demonstrated that prostate cancer cell line xenografts can be targeted specifically by labeled anti–TROP-2 agents in vivo. Conclusions: These results support further studies on TROP-2 as a therapeutic and diagnostic target for mCRPC.