Regadenoson Reduces Soluble Receptor for Advanced Glycation End-Products in Lung Recipients

BACKGROUND

The selective adenosine A2A receptor (A2AR) agonist regadenoson reduces inflammation due to lung ischemia-reperfusion injury (IRI). The objective of this study was to investigate molecular and cellular mechanisms by which regadenoson reduces IRI in lung transplant recipients.

METHODS

Fourteen human lung transplant recipients were infused for 12 hours with regadenoson and 7 more served as untreated controls. Plasma levels of high mobility group box 1 and its soluble receptor for advanced glycation end-products (sRAGE) were measured by Luminex. Matrix metalloproteinase (MMP) 2 and 9 were measured by gelatin zymography. Tissue inhibitor of metalloproteinase 1 was measured by mass spectroscopy. A2AR expression on leukocytes was analyzed by flow cytometry. MMP-9-mediated cleavage of RAGE was evaluated using cultured macrophages in vitro.

RESULTS

Regadenoson treatment during lung transplantation significantly reduced levels of MMP-9 (P < .05), but not MMP-2, and elevated levels of tissue inhibitor of metalloproteinase 1 (P < .05), an endogenous selective inhibitor of MMP-9. Regadenoson infusion significantly reduced plasma levels of sRAGE (P < .05) during lung reperfusion compared with control subjects. A2AR expression was highest on invariant natural killer T cells and higher on monocytes than other circulating immune cells (P < .05). The shedding of RAGE from cultured monocytes/macrophages was increased by MMP-9 stimulation and reduced by an MMP inhibitor or by A2AR agonists, regadenoson or ATL146e.

CONCLUSIONS

In vivo and in vitro studies suggest that A2AR activation reduces sRAGE in part by inhibiting MMP-9 production by monocytes/macrophages. These results suggest a novel molecular mechanism by which A2AR agonists reduce primary graft dysfunction.

Regadenoson for the treatment of COVID-19: A five case clinical series and mouse studies

BACKGROUND

Adenosine inhibits the activation of most immune cells and platelets. Selective adenosine A2A receptor (A2AR) agonists such as regadenoson (RA) reduce inflammation in most tissues, including lungs injured by hypoxia, ischemia, transplantation, or sickle cell anemia, principally by suppressing the activation of invariant natural killer T (iNKT) cells. The anti-inflammatory effects of RA are magnified in injured tissues due to induction in immune cells of A2ARs and ecto-enzymes CD39 and CD73 that convert ATP to adenosine in the extracellular space. Here we describe the results of a five patient study designed to evaluate RA safety and to seek evidence of reduced cytokine storm in hospitalized COVID-19 patients.

METHODS AND FINDINGS

Five COVID-19 patients requiring supplemental oxygen but not intubation (WHO stages 4-5) were infused IV with a loading RA dose of 5 μg/kg/h for 0.5 h followed by a maintenance dose of 1.44 μg/kg/h for 6 hours, Vital signs and arterial oxygen saturation were recorded, and blood samples were collected before, during and after RA infusion for analysis of CRP, D-dimer, circulating iNKT cell activation state and plasma levels of 13 proinflammatory cytokines. RA was devoid of serious side effects, and within 24 hours from the start of infusion was associated with increased oxygen saturation (93.8 ± 0.58 vs 96.6 ± 1.08%, P<0.05), decreased D-dimer (754 ± 17 vs 518 ± 98 ng/ml, P<0.05), and a trend toward decreased CRP (3.80 ± 1.40 vs 1.98 ± 0.74 mg/dL, P = 0.075). Circulating iNKT cells, but not conventional T cells, were highly activated in COVID-19 patients (65% vs 5% CD69+). RA infusion for 30 minutes reduced iNKT cell activation by 50% (P<0.01). RA infusion for 30 minutes did not influence plasma cytokines, but infusion for 4.5 or 24 hours reduced levels of 11 of 13 proinflammatory cytokines. In separate mouse studies, subcutaneous RA infusion from Alzet minipumps at 1.44 μg/kg/h increased 10-day survival of SARS-CoV-2-infected K18-hACE2 mice from 10 to 40% (P<0.001).

CONCLUSIONS

Infused RA is safe and produces rapid anti-inflammatory effects mediated by A2A adenosine receptors on iNKT cells and possibly in part by A2ARs on other immune cells and platelets. We speculate that iNKT cells are activated by release of injury-induced glycolipid antigens and/or alarmins such as IL-33 derived from virally infected type II epithelial cells which in turn activate iNKT cells and secondarily other immune cells. Adenosine released from hypoxic tissues, or RA infused as an anti-inflammatory agent decrease proinflammatory cytokines and may be useful for treating cytokine storm in patients with Covid-19 or other inflammatory lung diseases or trauma.

Evidence That Binding of Cyclic GMP to the Extracellular Domain of NKA (Sodium-Potassium ATPase) Mediates Natriuresis

BACKGROUND

Extracellular renal interstitial guanosine cyclic 3',5'-monophosphate (cGMP) inhibits renal proximal tubule (RPT) sodium (Na+) reabsorption via Src (Src family kinase) activation. Through which target extracellular cGMP acts to induce natriuresis is unknown. We hypothesized that cGMP binds to the extracellular α1-subunit of NKA (sodium-potassium ATPase) on RPT basolateral membranes to inhibit Na+ transport similar to ouabain-a cardiotonic steroid.

METHODS

Urine Na+ excretion was measured in uninephrectomized 12-week-old female Sprague-Dawley rats that received renal interstitial infusions of vehicle (5% dextrose in water), cGMP (18, 36, and 72 μg/kg per minute; 30 minutes each), or cGMP+rostafuroxin (12 ng/kg per minute) or were subjected to pressure-natriuresis±rostafuroxin infusion. Rostafuroxin is a digitoxigenin derivative that displaces ouabain from NKA.

RESULTS

Renal interstitial cGMP and raised renal perfusion pressure induced natriuresis and increased phosphorylated SrcTyr416 and Erk 1/2 (extracellular signal-regulated protein kinase 1/2)Thr202/Tyr204; these responses were abolished with rostafuroxin coinfusion. To assess cGMP binding to NKA, we performed competitive binding studies with isolated rat RPTs using bodipy-ouabain (2 μM)+cGMP (10 µM) or rostafuroxin (10 µM) and 8-biotin-11-cGMP (2 μM)+ouabain (10 μM) or rostafuroxin (10 µM). cGMP or rostafuroxin reduced bodipy-ouabain fluorescence intensity, and ouabain or rostafuroxin reduced 8-biotin-11-cGMP staining. We cross-linked isolated rat RPTs with 4-N3-PET-8-biotin-11-cGMP (2 μM); 8-N3-6-biotin-10-cAMP served as negative control. Precipitation with streptavidin beads followed by immunoblot analysis showed that RPTs after cross-linking with 4-N3-PET-8-biotin-11-cGMP exhibited a significantly stronger signal for NKA than non-cross-linked samples and cross-linked or non-cross-linked 8-N3-6-biotin-10-cAMP RPTs. Ouabain (10 μM) reduced NKA in cross-linked 4-N3-PET-8-biotin-11-cGMP RPTs confirming fluorescence staining. 4-N3-PET-8-biotin-11-cGMP cross-linked samples were separated by SDS gel electrophoresis and slices corresponding to NKA molecular weight excised and processed for mass spectrometry. NKA was the second most abundant protein with 50 unique NKA peptides covering 47% of amino acids in NKA. Molecular modeling demonstrated a potential cGMP docking site in the ouabain-binding pocket of NKA.

CONCLUSIONS

cGMP can bind to NKA and thereby mediate natriuresis.

Isotonic design for phase I cancer clinical trials with late-onset toxicities

This article addresses the problem of identifying the maximum tolerated dose (MTD) in Phase I dose-finding clinical trials with late-onset toxicities. The main design challenge is how best to adaptively allocate study participants to tolerable doses when the evaluation window for the toxicity endpoint is long relative to the accrual rate of new participants. We propose a new design framework based on order-restricted statistical inference that addresses this challenge in sequential dose assignments. We illustrate the proposed method on real data from a Phase I trial of bortezomib in lymphoma patients and apply it to a Phase I trial of radiotherapy in prostate cancer patients. We conduct extensive simulation studies to compare our design's operating characteristics to existing published methods. Overall, our proposed design demonstrates good performance relative to existing methods in allocating participants at and around the MTD during the study and accurately recommending the MTD at the study conclusion.

Standardizing Prostaglandin Initiation in Prenatally Diagnosed Ductal-Dependent Neonates; A Quality Initiative

Prostaglandin E1 (PGE) is used in patients with ductal-dependent congenital heart disease (CHD). Side effects of apnea and fever are often dose dependent and occur within 48 h after initiation. We initiated a standardized approach to PGE initiation after our institution recognized a high incidence of side effects and a wide variety of starting doses of PGE. Neonates with prenatally diagnosed ductal-dependent CHD were identified, started on a standardized protocol that started PGE at 0.01 mcg/kg/min, and evaluated for PGE related side effects. Compliance, outcomes and dose adjustments during the first 48 h post-PGE initiation were evaluated. Fifty patients were identified (25 pre-intervention; 25 post-intervention). After intervention, compliance with the protocol was 96%, and apnea or fever occurred in 28% (compared to 63% pre-intervention, p = 0.015). Dose adjustments (either increase or decrease) prior to cardiac surgery were similar in both cohorts (60%, 52%, p = 0.569). There were no mortalities or emergent procedures performed due to ductus arteriosus closure. Standardizing a protocol for initiating PGE in prenatally diagnosed ductal-dependent CHD was successful and reduced the incidence of apnea, fever, and sepsis evaluations. A starting dose of 0.01 mcg/kg/min did not cause increased adverse effects.

Collateral status, hyperglycemia, and functional outcome after acute ischemic stroke

BACKGROUND

Mixed data exist regarding the association between hyperglycemia and functional outcome after acute ischemic stroke when accounting for the impact of leptomeningeal collateral flow. We sought to determine whether collateral status modifies the association between treatment group and functional outcome in a subset of patients with large vessel occlusion enrolled in the Stroke Hyperglycemia Insulin Network Effort (SHINE) trial.

METHODS

In this post-hoc analysis, we analyzed patients enrolled into the SHINE trial with anterior circulation large vessel occlusion who underwent imaging with CT angiography prior to glucose control treatment group assignment. The primary analysis assessed the degree to which collateral status modified the effect between treatment group and functional outcome as defined by the 90-day modified Rankin Scale score. Logistic regression was used to model the data, with adjustments made for thrombectomy status, age, post-perfusion thrombolysis in cerebral infarction (TICI) score, tissue plasminogen activator (tPA) use, and baseline National Institutes of Health Stroke Scale (NIHSS) score. Five SHINE trial centers contributed data for this analysis. Statistical significance was defined as a p-value < 0.05.

RESULTS

Among the 1151 patients in the SHINE trial, 57 with angiographic data were included in this sub-analysis, of whom 19 had poor collaterals and 38 had good collaterals. While collateral status had no effect (p = 0.855) on the association between glucose control treatment group and functional outcome, patients with good collaterals were more likely to have a favorable functional outcome (p = 0.001, OR 5.02; 95% CI 1.37-16.0).

CONCLUSIONS

In a post-hoc analysis using a subset of patients with angiographic data enrolled in the SHINE trial, collateral status did not modify the association between glucose control treatment group and functional outcome. However, consistent with prior studies, there was a significant association between good collateral status and favorable outcome in patients with large vessel occlusion stroke.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier is NCT01369069. Registration date is June 8, 2011.

Ceramide nanoliposomes augment the efficacy of venetoclax and cytarabine in models of acute myeloid leukemia

Despite several new therapeutic options for acute myeloid leukemia (AML), disease relapse remains a significant challenge. We have previously demonstrated that augmenting ceramides can counter various drug-resistance mechanisms, leading to enhanced cell death in cancer cells and extended survival in animal models. Using a nanoscale delivery system for ceramide (ceramide nanoliposomes, CNL), we investigated the effect of CNL within a standard of care venetoclax/cytarabine (Ara-C) regimen. We demonstrate that CNL augmented the efficacy of venetoclax/cytarabine in in vitro, ex vivo, and in vivo models of AML. CNL treatment induced non-apoptotic cytotoxicity, and augmented cell death induced by Ara-C and venetoclax. Mechanistically, CNL reduced both venetoclax (Mcl-1) and cytarabine (Chk1) drug-resistant signaling pathways. Moreover, venetoclax and Ara-C augmented the generation of endogenous pro-death ceramide species, which was intensified with CNL. Taken together, CNL has the potential to be utilized as an adjuvant therapy to improve outcomes, potentially extending survival, in patients with AML.

Breast Cancer Antiestrogen Resistance 3 (BCAR3) promotes tumor growth and progression in triple-negative breast cancer

Triple-Negative Breast Cancers (TNBCs) constitute roughly 10-20% of breast cancers and are associated with poor clinical outcomes. Previous work from our laboratory and others has determined that the cytoplasmic adaptor protein Breast Cancer Antiestrogen Resistance 3 (BCAR3) is an important promoter of cell motility and invasion of breast cancer cells. In this study, we use both in vivo and in vitro approaches to extend our understanding of BCAR3 function in TNBC. We show that BCAR3 is upregulated in ductal carcinoma in situ (DCIS) and invasive carcinomas compared to normal mammary tissue, and that survival of TNBC patients whose tumors contained elevated BCAR3 mRNA is reduced relative to individuals whose tumors had less BCAR3 mRNA. Using mouse orthotopic tumor models, we further show that BCAR3 is required for efficient TNBC tumor growth. Analysis of publicly available RNA expression databases revealed that MET receptor signaling is strongly correlated with BCAR3 mRNA expression. A functional role for BCAR3-MET coupling is supported by data showing that both proteins participate in a single pathway to control proliferation and migration of TNBC cells. Interestingly, the mechanism through which this functional interaction operates appears to differ in different genetic backgrounds of TNBC, stemming in one case from potential differences in the strength of downstream signaling by the MET receptor and in another from BCAR3-dependent activation of an autocrine loop involving the production of HGF mRNA. Together, these data open the possibility for new approaches to personalized therapy for individuals with TNBCs.

Immune mechanisms orchestrate tertiary lymphoid structures in tumors via cancer-associated fibroblasts

Tumor-associated tertiary lymphoid structures (TA-TLS) are associated with enhanced patient survival and responsiveness to cancer therapies, but the mechanisms underlying their development are unknown. We show here that TA-TLS development in murine melanoma is orchestrated by cancer-associated fibroblasts (CAF) with characteristics of lymphoid tissue organizer cells that are induced by tumor necrosis factor receptor signaling. CAF organization into reticular networks is mediated by CD8 T cells, while CAF accumulation and TA-TLS expansion depend on CXCL13-mediated recruitment of B cells expressing lymphotoxin-α1β2. Some of these elements are also overrepresented in human TA-TLS. Additionally, we demonstrate that immunotherapy induces more and larger TA-TLS that are more often organized with discrete T and B cell zones, and that TA-TLS presence, number, and size are correlated with reduced tumor size and overall response to checkpoint immunotherapy. This work provides a platform for manipulating TA-TLS development as a cancer immunotherapy strategy.

Timing of Introduction of Complementary Foods and Beverages to Infants of Low-Income Women

Background: Although rates of complementary food and beverage (CFB) consumption among infants under 4 to 6 months of age have been declining, they remain well above the American Academy of Pediatrics (AAPs) recommendations. It is unclear if women with low income in the United States are more likely than other women to introduce CFBs early. We examined timing of introduction of CFBs to infants of mothers with low income to further illuminate infant feeding practices in this potentially vulnerable population. Materials and Methods: We analyzed infant feeding data collected prospectively from 443 mother-infant dyads. Data were obtained by interview at 1, 3, and 6 months postpartum. We used Kaplan-Meier curves to show time to introduction of CFBs overall and by type of CFB, and log-rank tests to compare timing by demographic and clinical characteristics. Results: Participants were mostly non-Hispanic black or white, with a high school education or less. By month 3, 48% of infants were fed at least one CFB, increasing to over 83% by month 5. Women who did not work outside the home introduced CFBs significantly earlier than those who worked, as did women who smoked compared with those who did not. Timing did not differ by other participant characteristics. Conclusions: Introduction of CFBs before 4-6 months was common. Clinical guidance and intervention programs should support mothers toward the goal of improving infant diets in this at-risk population.

Hospital Survival After Surgical Repair of Truncus Arteriosus with Interrupted Aortic Arch: Results from a Multi-institutional Database

Truncus arteriosus (TA) is a major congenital cardiac malformation that requires surgical repair in the first few weeks of life. Interrupted aortic arch (IAA) is an associated malformation that significantly impacts the complexity of the TA operation. The aim of this study was to (1) define the comorbid conditions associated with TA and (2) determine the hospital survival and morbidity of patients with TA with and without an IAA. Data was collected from the Vizient Clinical Database/Resource Manager, formerly University HealthSystem Consortium, which encompasses more than 160 academic medical centers in the United States. The database was queried for patients admitted from 2002 to 2016 who were ≤ 4 months of age at initial admission, diagnosed with TA, and underwent complete surgical repair during that hospitalization. Of the 645 patients with TA who underwent surgery, 98 (15%) had TA with an interrupted aortic arch (TA-IAA). Both TA and TA-IAA were associated with a high prevalence of comorbidities, including DiGeorge syndrome, prematurity, and other congenital malformations. There was no difference in mortality between TA and TA-IAA (13.7-18.4%, p value = 0.227). No comorbid conditions were associated with an increased mortality in either group. However, patients with TA-IAA had a longer post-operative length of stay (LOS) compared to those without IAA (30 versus 40.3 days, p value = 0.001) and this effect was additive with each additional comorbid condition. In conclusion, the addition of IAA to TA is associated with an increased post-operative LOS, but does not increase in-hospital mortality.

Abstract 4: Glucose Control and Risk of Tpa-Related Symptomatic Intracerebral Hemorrhage in Patients With Hyperglycemic Acute Ischemic Stroke: Preplanned Analysis From the SHINE Trial

Introduction: In acute ischemic stroke (AIS), hyperglycemia promotes enhanced blood brain barrier permeability, tissue acidosis, and oxygen free radicals, and may increase risk of post-tPA symptomatic intracerebral hemorrhage (sICH). We performed a pre-planned analysis from the SHINE trial (NCT01369069) to examine the effects of blood glucose (BG) control on post-thrombolysis ICH.

Hypothesis: In AIS, (1) post-tPA BG measures are associated with sICH, and (2) intensive insulin therapy can reduce the risk of sICH.

Methods: Hyperglycemic AIS patients <12 hours onset were randomized to intensive insulin (target range 80-130 mg/dL) vs standard BG control (80-179 mg/dL) over a 72-hour period. Randomization was stratified by tPA treatment. Three independent vascular neurologists reviewed all sICH events occurring within 7 days, defined by neurologic deterioration of ≥4 points on the NIHSS. Associations between BG control and sICH were analyzed using a logistic regression model accounting for NIHSS, age, systolic blood pressure, onset to tPA time, and endovascular therapy. Associations were reported as odds ratios (95% CI). Categorical variables and outcomes were compared using the chi-square test (p < 0.05).

Results: Of the 1151 SHINE participants, 725 (63%) received IV tPA (median age 65, 46% women, 29% Black, 18% Hispanic). Median NIHSS was 7, baseline BG 187 (IQR 153-247) mg/dL, and onset to tPA was 2.2 hrs (1.6-2.9). Post-tPA sICH occurred in 3.6% (3% intensive vs. 4.3% standard, OR 1.10, 95% CI 0.60-2.01, p=0.697). There was a consistent association between post-tPA BG measures and sICH. In the first 12 hours, every 10 mg/dL increase in median BG increased odds of sICH by ~8% (OR 1.08, 95% CI 1.03-1.14, p=0.004), and a greater percentage of BG measures 80-130 mg/dL decreased odds of sICH by ~11% (0.89, 95% CI 0.80-0.99, p=0.030).

Conclusion: In this pre-planned analysis, intensive insulin therapy was not associated with a reduced risk of post-tPA sICH. However, post-tPA hyperglycemia was associated with a higher risk of sICH overall, particularly in the early post-treatment period. These data provide class IIa, level B-R evidence that post-tPA glucose levels between 80-130 mg/dL are associated with decreased risk of sICH. Acknowledgments: NIH-NINDS U01 NS069498.

Differential Expression of CD49a and CD49b Determines Localization and Function of Tumor-Infiltrating CD8+ T Cells

CD8⁺ T-cell infiltration and effector activity in tumors are correlated with better overall survival of patients, suggesting that the ability of T cells to enter and remain in contact with tumor cells supports tumor control. CD8⁺ T cells express the collagen-binding integrins CD49a and CD49b, but little is known about their function or how their expression is regulated in the tumor microenvironment (TME). Here, we found that tumor-infiltrating CD8⁺ T cells initially expressed CD49b, gained CD49a, and then lost CD49b over the course of tumor outgrowth. This differentiation sequence was driven by antigen-independent elements in the TME, although T-cell receptor (TCR) stimulation further increased CD49a expression. Expression of exhaustion markers and CD49a associated temporally but not mechanistically. Intratumoral CD49a-expressing CD8⁺ T cells failed to upregulate TCR-dependent Nur77 expression, whereas CD69 was constitutively expressed, consistent with both a lack of productive antigen engagement and a tissue-resident memory-like phenotype. Imaging T cells in live tumor slices revealed that CD49a increased their motility, especially of those in close proximity to tumor cells, suggesting that it may interfere with T-cell recognition of tumor cells by distracting them from productive engagement, although we were not able to augment productive engagement by short-term CD49a blockade. CD49b also promoted relocalization of T cells at a greater distance from tumor cells. Thus, our results demonstrate that expression of these integrins affects T-cell trafficking and localization in tumors via distinct mechanisms, and suggests a new way in which the TME, and likely collagen, could promote tumor-infiltrating CD8⁺ T-cell dysfunction.

Adapting isotonic dose-finding to a dynamic set of drug combinations with application to a phase I leukemia trial

BACKGROUND/AIMS

This article describes the proposed design of a phase I study evaluating the safety of ceramide nanoliposome and vinblastine among an initial set of 19 possible dose combinations in patients with relapsed/refractory acute myeloid leukemia and patients with untreated acute myeloid leukemia who are not candidates for intensive induction chemotherapy.

METHODS

Extensive collaboration between statisticians and clinical investigators revealed the need to incorporate several adaptive features into the design, including the flexibility of adding or eliminating certain dose combinations based on safety criteria applied to multiple dose pairs. During the design stage, additional dose levels of vinblastine were added, increasing the dimension of the drug combination space and thus the complexity of the problem. Increased complexity made application of existing drug combination dose-finding methods unsuitable in their current form.

RESULTS

Our solution to these challenges was to adapt a method based on isotonic regression to meet the research objectives of the study. Application of this adapted method is described herein, and a simulation study of the design's operating characteristics is conducted.

CONCLUSION

The aim of this article is to bring to light examples of novel design applications as a means of augmenting the implementation of innovative designs in the future and to demonstrate the flexibility of adaptive designs in satisfying changing design conditions.

Magnetic resonance imaging accurately tracks kidney pathology and heterogeneity in the transition from acute kidney injury to chronic kidney disease

Acute kidney injury (AKI) increases the risk for chronic kidney disease (CKD). However, there are few tools to detect microstructural changes after AKI. Here, cationic ferritin-enhanced magnetic resonance imaging (CFE-MRI) was applied to examine the heterogeneity of kidney pathology in the transition from AKI to CKD. Adult male mice received folic acid followed by cationic ferritin and were euthanized at four days (AKI), four weeks (CKD-4) or 12 weeks (CKD-12). Kidneys were examined by histologic methods and CFE-MRI. In the CKD-4 and CKD-12 groups, glomerular number was reduced and atubular cortical lesions were observed. Apparent glomerular volume was larger in the AKI, CKD-4 and CKD-12 groups compared to controls. Glomerular hypertrophy occurred with ageing. Interglomerular distance and glomerular density were combined with other MRI metrics to distinguish the AKI and CKD groups from controls. Despite significant heterogeneity, the noninvasive (MRI-based) metrics were as accurate as invasive (histological) metrics at distinguishing AKI and CKD from controls. To assess the toxicity of cationic ferritin in a CKD model, CKD-4 mice received cationic ferritin and were examined one week later. The CKD-4 groups with and without cationic ferritin were similar, except the iron content of the kidney, liver, and spleen was greater in the CKD-4 plus cationic ferritin group. Thus, our study demonstrates the accuracy and safety of CFE-MRI to detect whole kidney pathology allowing for the development of novel biomarkers of kidney disease and providing a foundation for future in vivo longitudinal studies in mouse models of AKI and CKD to track nephron fate.

Abstract B31: Endocervical microRNA profiling for detection of ovarian cancer

Though the necessity for ovarian cancer detection at earlier stages has long been acknowledged, biomarker-based discoveries have yielded underwhelming outcomes. The failures of CA-125 and other approaches have raised concern over the sensitivity and robustness of serum biomarkers. However, the discovery that most ovarian cancers originate in the fallopian tube may offer a unique opportunity; since the natural washdown of fallopian tube cells and debris travels through the uterus and into the cervix and vagina, we hypothesized that biomarkers may be concentrated in these proximal fluids. Though we previously demonstrated that tumor DNA is present in the vaginal tract of ovarian cancer patients, the deep sequencing required and low sensitivity (60%) render it insufficient for clinical use. Therefore, we examined other potential biomarkers with high stability that are detectable with methods that are cost effective and noninvasive, such as endocervical sampling. We performed mass spectroscopy on 41 endocervical cytobrush (ECC) samples and found the greatest discriminating pathway between ovarian cancer and benign patients was exosomal composition and trafficking (p=1.3 × 10−21). MicroRNAs (miRNAs) are common exosomal cargo, boast high extracellular stability in bodily fluids, and govern a multitude of cellular processes that can influence ovarian cancer initiation and progression. We therefore used NanoString to perform comprehensive miRNA profiling in matched ECC and plasma samples from high-grade serous ovarian cancer and normal patients. We discovered 13 significant differentially expressed ECC miRNAs and 7 plasma miRNAs individually capable of distinguishing cancer from normal. Not only did ECC samples yield a higher number of significant hits than plasma samples, but these hits also showed better sensitivity and specificity as assessed through their concordance index (c-index) scores generated by area under receiver operator curve analysis (c-index averages of 0.9141 in ECC vs. 0.8796 in plasma). 3 miRNAs overlapped between ECC and plasma, and in each case higher c-index scores were present in ECC samples than in plasma. ECC samples also showed more dramatic differences in expression between cancer and benign (1.4 log2 fold change in ECC vs. 0.8 log2 fold change in plasma), suggesting ECC may yield more consistent and detectable differences in miRNA expression than its plasma counterpart. The miRNAs discovered in our ECC samples showed individual sensitivities and specificities that lie within 95% confidence intervals, indicating potential for a viable positive predictive value for a clinical screening test. Crucial next steps are to validate these data in a larger cohort and determine if a similar distinguishing signature is present in the earliest events in fallopian tube transformation. Together, these data support further investigation of proximal tissue sampling for detection of ovarian cancer.

Citation Format: Alexandra R. Harris, Danielle C. Llaneza, Mark R. Conaway, Thomas P. Conrads, Katherine Croft, John R. Cornelison, Charles N. Landen. Endocervical microRNA profiling for detection of 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 B31.

Looking past PD-L1: expression of immune checkpoint TIM-3 and its ligand galectin-9 in cervical and vulvar squamous neoplasia

Immunotherapies targeting the PD-1/PD-L1 pathway have shown some success in cervical and vulvar squamous cell carcinomas, but little is known about the potential vulnerability of these tumors to other checkpoint inhibitors. TIM-3 is a checkpoint molecule that exerts immunosuppressive function via its interaction with Gal-9. TIM-3 and Gal-9 have been identified on a variety of malignancies but have not been studied in cervical and vulvar cancers, nor has their relationship to PD-L1 been established. Sixty-three cervical and vulvar invasive (n = 34) and intraepithelial lesions (n = 29) were assessed for TIM-3, Gal-9, and PD-L1 in tumor/lesional cells and associated immune cells. Tumoral TIM-3 expression was identified in 85% of squamous cell carcinomas but only 21% of intraepithelial lesions (p < 0.0001). When immune cells were also accounted for, 97% of invasive and 41% of intraepithelial lesions had a TIM-3 combined positive score (CPS) ≥ 1 (p < 0.0001). Tumoral membranous expression of Gal-9 was seen in 82% of squamous cell carcinomas and 31% of intraepithelial lesions (p = 0.0001); nearly all cases had Gal-9-positive immune cells. Tumoral PD-L1 was seen in 71% of squamous cell carcinomas and 10% of intraepithelial lesions (p < 0.0001), while the PD-L1 CPS was ≥1 in 82 and 21%, respectively (p < 0.0001). There were no significant differences in TIM-3, GAL-9, or PD-L1 expression in cervical vs. vulvar neoplasms, nor was HPV status significantly associated with any of the three markers. Dual TIM-3/Gal-9 expression was present in the majority (86%) of PD-L1-positive cases including 100% of PD-L1-positive squamous cell carcinomas, suggesting a possible role for TIM-3 checkpoint inhibition in concert with anti-PD-1/PD-L1.

Adenosine A2A receptor agonist (regadenoson) in human lung transplantation

BACKGROUND

Currently, there are no clinically approved treatments for ischemia-reperfusion injury after lung transplantation. Pre-clinical animal models have demonstrated a promising efficacy of adenosine _2A receptor (A_2AR) agonists as a treatment option for reducing ischemia-reperfusion injury. The purpose of this human study, is to conduct a Phase I clinical trial for evaluating the safety of continuous infusion of an A_2AR agonist in lung transplant recipients.

METHODS

An adaptive, two-stage continual reassessment trial was designed to evaluate the safety of regadenoson (A_2AR agonist) in the setting of lung transplantation. Continuous infusion of regadenoson was administered to lung transplant recipients that was started at the time of skin incision. Adverse events and dose-limiting toxicities, as pre-determined by a study team and assessed by a clinical team and an independent safety monitor, were the primary end-points for safety in this trial.

RESULTS

Between January 2018 and March 2019, 14 recipients were enrolled in the trial. Of these, 10 received the maximum infused dose of 1.44 µg/kg/min for 12 hours. No dose-limiting toxicities were observed. The steady-state plasma regadenoson levels sampled before the reperfusion of the first lung were 0.98 ± 0.46 ng/ml. There were no mortalities within 30 days.

CONCLUSIONS

Regadenoson, an A_2AR agonist, can be safely infused in the setting of lung transplantation with no dose-limiting toxicities or drug-related mortality. Although not powered for the evaluation of secondary end-points, the results of this trial and the outcome of pre-clinical studies warrant further investigation with a Phase II randomized controlled trial.

Understanding the asthmatic response to an experimental rhinovirus infection: Exploring the effects of blocking IgE

BACKGROUND

Rhinovirus frequently causes asthma exacerbations among children and young adults who are allergic. The interaction between allergen and rhinovirus-induced symptoms and inflammation over time is unclear.

OBJECTIVE

Our aim was to compare the response to an experimental inoculation with rhinovirus-16 in allergic asthmatics with the response in healthy controls and to evaluate the effects of administrating omalizumab before and during the infection.

METHODS

Two clinical trials were run in parallel. In one of these trials, the response to an experimental inoculation with rhinovirus-16 among asthmatics with high levels of total IgE was compared to the response in healthy controls. The other trial compared the effects of administering omalizumab versus placebo to asthmatics in a randomized, double-blind placebo-controlled investigation. The primary outcome for both trials compared lower respiratory tract symptoms (LRTSs) between study groups over the first 4 days of infection.

RESULTS

Frequent comparisons of symptoms, lung function, and blood eosinophil counts revealed differences that were more pronounced among allergic asthmatics than among controls by days 2 and 3 after virus inoculation. Additionally, an augmentation of upper respiratory tract symptom scores and LRTS scores occurred among the atopic asthmatics versus the controls during the resolution of symptoms (P < .01 for upper respiratory symptom tract scores and P < .001 for LRTS scores). The beneficial effects of administering omalizumab on reducing LRTSs and improving lung function were strongest over the first 4 days.

CONCLUSIONS

LRTSs and blood eosinophil counts were augmented and lung function was reduced among allergic asthmatics early after rhinovirus inoculation but increased late in the infection during symptom resolution. The effect of administering omalizumab on the response to rhinovirus was most pronounced during the early/innate phase of the infection.

Coherence principles in interval-based dose finding

This paper studies the notion of coherence in interval-based dose-finding methods. An incoherent decision is either (a) a recommendation to escalate the dose following an observed dose-limiting toxicity or (b) a recommendation to deescalate the dose following a non-dose-limiting toxicity. In a simulated example, we illustrate that the Bayesian optimal interval method and the Keyboard method are not coherent. We generated dose-limiting toxicity outcomes under an assumed set of true probabilities for a trial of n=36 patients in cohorts of size 1, and we counted the number of incoherent dosing decisions that were made throughout this simulated trial. Each of the methods studied resulted in 13/36 (36%) incoherent decisions in the simulated trial. Additionally, for two different target dose-limiting toxicity rates, 20% and 30%, and a sample size of n=30 patients, we randomly generated 100 dose-toxicity curves and tabulated the number of incoherent decisions made by each method in 1000 simulated trials under each curve. For each method studied, the probability of incurring at least one incoherent decision during the conduct of a single trial is greater than 75%. Coherency is an important principle in the conduct of dose-finding trials. Interval-based methods violate this principle for cohorts of size 1 and require additional modifications to overcome this shortcoming. Researchers need to take a closer look at the dose assignment behavior of interval-based methods when using them to plan dose-finding studies.

A MULTICENTER STUDY EVALUATING PERCEPTIONS AND KNOWLEDGE OF INPATIENT GLYCEMIC CONTROL AMONG RESIDENT PHYSICIANS: ANALYZING THEMES TO INFORM AND IMPROVE CARE

Objective: In this descriptive study, we evaluated perceptions and knowledge of inpatient glycemic control among resident physicians. Methods: We performed this study at four academic medical centers: the University of Mississippi Medical Center, University of Virginia Health System, University of Louisville Health Sciences Center, and Emory University. We designed a questionnaire, and Institutional Review Board approval was granted at each institution prior to study initiation. We then administered the questionnaire to Internal Medicine and Medicine-Pediatric resident physicians. Results: A total of 246 of 438 (56.2%) eligible resident physicians completed the Inpatient Glycemic Control Questionnaire (IGCQ). Most respondents (85.4%) reported feeling comfortable treating and managing inpatient hyperglycemia, and a majority (66.3%) agreed they had received adequate education. Despite self-reported comfort with knowledge, only 51.2% of respondents could identify appropriate glycemic targets in critically ill patients. Only 45.5% correctly identified appropriate inpatient random glycemic target values in noncritically ill patients, and only 34.1% of respondents knew appropriate preprandial glycemic targets in noncritically ill patients. A small majority (54.1%) were able to identify the correct fingerstick glucose value that defines hypoglycemia. System issues were the most commonly cited barrier to successful inpatient glycemic control. Conclusion: Most respondents reported feeling comfortable managing inpatient hyperglycemia but had difficulty identifying appropriate inpatient glycemic target values. Future interventions could utilize the IGCQ as a pre- and postassessment tool and focus on early resident education along with improving system environments to aid in successful inpatient glycemic control. Abbreviations: DM = diabetes mellitus; Emory = Emory University Healthcare; IGC = inpatient glycemic control; IGCQ = Inpatient Glycemic Control Questionnaire; IRB = Institutional Review Board; PGY = postgraduate year; UMMC = University of Mississippi Medical Center; UVA = University of Virginia Health System; UL = University of Louisville Health Sciences Center.

Construction and preliminary evaluation of the inpatient glycemic control questionnaire (IGCQ): a survey tool assessing perceptions and knowledge of resident physicians

BACKGROUND

Uncontrolled hyperglycemia in hospitalized patients, with or without diabetes mellitus, is associated with many adverse outcomes. Resident physicians are the primary managers of inpatient glycemic control (IGC) in many academic and community medical centers; however, no validated survey tools related to their perceptions and knowledge of IGC are currently available. As identification of common barriers to successful IGC amongst resident physicians may help foster better educational interventions (ultimately leading to improvements in IGC and patient care), we sought to construct and preliminarily evaluate such a survey tool.

METHODS

We developed the IGC questionnaire (IGCQ) by using previously published but unvalidated survey tools related to physician perspectives on inpatient glycemic control as a framework. We administered the IGCQ to a cohort of resident physicians from the University of Mississippi Medical Center, University of Louisville, Emory University, and the University of Virginia. We then used classical test theory and Rasch Partial Credit Model analyses to preliminarily evaluate and revise the IGCQ. The final survey tool contains 16 total items and three answer-choice categories for most items.

RESULTS

Two hundred forty-six of 438 (56.2%) eligible resident physicians completed the IGCQ during various phases of development.

CONCLUSIONS

We constructed and preliminarily evaluated the IGCQ, a survey tool that may be useful for future research into resident physician perceptions and knowledge of IGC. Future studies could seek to externally validate the IGCQ and then utilize the survey tool in pre- and post-intervention assessments.

Consequences of Performing Parallel Dose Finding Trials in Heterogeneous Groups of Patients

Patient heterogeneity, in which patients can be grouped by risk of toxicity, is a design challenge in early phase dose finding trials. Carrying out independent trials for each group is a readily available approach for dose finding. However, this often leads to dose recommendations that violate the known order of toxicity risk by group, or reversals in dose recommendation. In this manuscript, trials for partially ordered groups are simulated using four approaches: independent parallel trials using the continual reassessment method (CRM), Bayesian optimal interval design, and 3 + 3 methods, as well as CRM for partially ordered groups. Multiple group order structures are considered, allowing for varying amounts of group frailty order information. These simulations find that parallel trials in the presence of partially ordered groups display a high frequency of trials resulting in reversals. Reversals occur when dose recommendations do not follow known order of toxicity risk by group, such as recommending a higher dose level in a group of patients known to have a higher risk of toxicity. CRM for partially ordered groups eliminates the issue of reversals, and simulation results indicate improved frequency of maximum tolerated dose selection as well as treating a greater proportion of trial patients at this dose compared with parallel trials. When information is available on differences in toxicity risk by patient subgroup, methods designed to account for known group ordering should be considered to avoid reversals in dose recommendations and improve operating characteristics.

Acid ceramidase promotes drug resistance in acute myeloid leukemia through NF-κB-dependent P-glycoprotein upregulation

Acute myeloid leukemia (AML) is the most common acute leukemia in adults. More than half of older AML patients fail to respond to cytotoxic chemotherapy, and most responders relapse with drug-resistant disease. Failure to achieve complete remission can be partly attributed to the drug resistance advantage of AML blasts that frequently express P-glycoprotein (P-gp), an ATP-binding cassette transporter. Our previous work showed that elevated acid ceramidase (AC) levels in AML contribute to blast survival. Here, we investigated P-gp expression levels in AML relative to AC. Using parental HL-60 cells and drug-resistant derivatives as our model, we found that P-gp expression and efflux activity were highly upregulated in resistant derivatives. AC overexpression in HL-60 conferred resistance to the AML chemotherapeutic drugs, cytarabine, mitoxantrone, and daunorubicin, and was linked to P-gp upregulation. Furthermore, targeting AC through pharmacologic or genetic approaches decreased P-gp levels and increased sensitivity to chemotherapeutic drugs. Mechanistically, AC overexpression increased NF-κB activation whereas NF-kB inhibitors reduced P-gp levels, indicating that the NF-kappaB pathway contributes to AC-mediated modulation of P-gp expression. Hence, our data support an important role for AC in drug resistance as well as survival and suggest that sphingolipid targeting approaches may also impact drug resistance in AML.

Behavioral Strategies to Lower Postprandial Glucose in Those with Type 2 Diabetes May Also Lower Risk of Coronary Heart Disease

INTRODUCTION

Efforts to lower glycosylated hemoglobin (A1c) in patients with type 2 diabetes (T2D) are intended to reduce the risk of diabetic complications, but A1c is not the only factor contributing to this risk. Consequently, we re-analyzed published data from a broad-spectrum lifestyle intervention that lowered A1c to assess its effectiveness in lowering the overall risk of two complications of T2D, namely, coronary heart disease (CHD) and stroke.

METHODS

Data from 37 adults who participated in a randomized clinical trial of a lifestyle intervention intended to reduce postprandial glucose (PPG) were re-analyzed for their pre- and post-treatment risk of CHD and stroke using the T2D-specific UK Prospective Diabetes Study (UKPDS) v2.0 risk algorithm.

RESULTS

Compared to participants who received routine care, those using the lifestyle intervention had a significantly greater reduction in 10-year risk for CHD, but not for stroke.

CONCLUSION

These secondary analyses suggest that broad-spectrum lifestyle interventions that focus on lowering PPG may lower the risk of future CHD, which could guide future research.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT02432391.

Reasons for Early Cessation of Breastfeeding Among Women with Low Income

Background: Most women in the United States do not meet their breastfeeding goals, and low-income women breastfeed at lower rates than the general population. While risk factors for early cessation have been documented, specific reasons for discontinuing among this population are less understood. We examined reasons for cessation among low-income mothers to inform the development of targeted strategies to address breastfeeding disparities. Materials and Methods: We performed a secondary data analysis using prospective data collected during a randomized intervention trial of Special Supplemental Nutrition Program for Women, Infants, and Children (WIC)-eligible women interviewed in the third trimester and at 1, 3, and 6 months postpartum. We included the 221 women who initiated breastfeeding and stopped by 6 months. Women's reasons for discontinuing breastfeeding were grouped by thematic category and compared by time of breastfeeding cessation. Results: The most common reasons reported overall for breastfeeding cessation were concerns about breast milk supply and latch difficulty. Some reasons differed significantly by time of cessation. Latch difficulty was reported most often by women who breastfed for 1 month or less; supply concerns increased with increasing breastfeeding duration. Returning to work/school was uncommonly reported for those who stopped by 1 month, but more frequently reported in those with later cessation. Conclusions: We found that low-income women reported similar reasons for early breastfeeding cessation as have been reported for other populations of women. These results underscore the need for appropriately timed, culturally sensitive interventions to reduce disparities in duration of breastfeeding, specifically to address latch difficulty in the first few weeks and supply concerns as infants grow.

A Randomized Trial of Prenatal Video Education to Improve Breastfeeding Among Low-Income Women

Background: Many women initiate breastfeeding but do not meet their duration goals, and low-income women initiate and continue breastfeeding at lower rates than their counterparts. One-on-one counseling is associated with increased breastfeeding but requires significant resources. In contrast, video education, which requires fewer resources and is effective in other health care settings, such as vaccine uptake, has gone untested for prolonging breastfeeding duration among low-income women. Objective: To determine whether use of an educational breastfeeding video shown individually to low-income pregnant women in the prenatal clinic would prolong duration of any and exclusive breastfeeding. Methods: A multicenter, randomized, controlled trial was conducted in four prenatal clinics. Low-income pregnant women were randomized to view the intervention (breastfeeding education) or control (prenatal nutrition) video in the third trimester and interviewed by telephone at 1, 3, and 6 months postpartum about infant feeding practices. Kaplan-Meier survival curves with log-rank tests and Cox proportional hazards regression were utilized to compare groups. Results: Of the 816 eligible women approached, 64% participated: 263 assigned to the intervention, and 259 assigned to the control. Six-month data were obtained for 211 (80%) and 220 (85%) women, respectively. Rate of breastfeeding cessation did not differ by group (hazard ratios; HR = 1.00, 95% confidence interval [CI]: 0.81-1.24 and HR = 0.93, 95% CI: 0.76-1.14, for any and exclusive breastfeeding, respectively). Conclusion: A single viewing of a breastfeeding education video shown in the prenatal clinic did not impact breastfeeding duration or exclusivity among low-income women in this study. Although not sufficient alone, educational videos may be useful as one component of a comprehensive program to promote breastfeeding.

Vitamin D pathway activation selectively deactivates signal transducer and activator of transcription (STAT) proteins and inflammatory cytokine production in natural killer leukemic large granular lymphocytes

Calcitriol, the active form of vitamin D, has been well documented to act directly on immune cells and malignant cells. Activated T cells are one of the best characterized targets of calcitriol, with effects including decreasing inflammatory cytokine output and promoting anti-inflammatory cytokine production. However, the effects of calcitriol on natural killer (NK) cells are less clear. Reports suggest that only immature NK cell populations are affected by calcitriol treatment resulting in impaired cytotoxic function and cytokine production, while mature NK cells may have little or no response. NK cell large granular lymphocyte leukemia (NK-LGLL) is a rare leukemia with CD3-CD16+CD56+NK cell clonal expansion. The current standard treatments are immunosuppressant therapies, which are not curative. The Janus kinase (JAK) - signal transducer and activator of transcription (STAT) pathway is hyperactivated in LGLL and is one pathway of interest in new drug target investigations. We previously demonstrated the ability of calcitriol to decrease STAT1 tyrosine 701 (p-STAT1) and STAT3 tyrosine 705 (p-STAT3) phosphorylation as well as inflammatory cytokine output of T cell large granular lymphocyte leukemia cells, but did not determine the effects of calcitriol on NK-LGLL. Therefore, in the present study, we investigated whether NKL cells, a model of NK-LGLL, and NK-LGLL patient peripheral blood mononuclear cells (PBMCs) are susceptible to treatment with calcitriol or seocalcitol (EB1089), a potent analog of calcitriol. NKL cells are dependent on interleukin (IL)-2 for survival and we show here for the first time that treatment with IL-2 induced tyrosine phosphorylation of STATs 1 through 6. Both calcitriol and EB1089 caused significant upregulation of the vitamin D receptor (VDR). IL-2 induction of p-STAT1 and p-STAT3 phosphorylation was significantly decreased after calcitriol or EB1089 treatment. Additionally, IL-10, interferon (IFN)-γ, and FMS-like tyrosine kinase 3 ligand (Flt-3L) extracellular output was significantly decreased at 100 nM EB1089 and intracellular IL-10 was decreased with either calcitriol or EB1089 treatment. We treated NK-LGLL patient PBMCs with calcitriol or EB1089 and found decreased p-STAT1 and p-STAT3 while VDR increased, which matched the NKL cell line data. We then measured 75 serum cytokines in NK-LGLL patients (n = 8) vs. age- and sex-matched normal healthy donors (n = 8), which is the first serum cytokine study for this LGLL subtype. We identified 15 cytokines, including IL-10 and Flt-3L, which were significantly different between normal donors and NK-LGLL patients. Overall, our results suggest that activating the vitamin D pathway could be a mechanism to decrease STAT1 and 3 activation and inflammatory cytokine output in NK-LGLL patients.

The Impact of Early-Phase Trial Design in the Drug Development Process

PURPOSE

Many of the therapeutic agents that are being used currently were developed using the 3+3 decision rule for dose finding. Over the past 30 years, several dose-finding designs have been proposed and evaluated, including the "continual reassessment method" (CRM) and the "Bayesian optimal interval design" (BOIN). This research investigates the role of the choice of an early-phase design on the likelihood that drugs entering the drug development pipeline will have 2 successful phase III trials.Experimental Design: Using simulation, each agent in a population of hypothetical agents was tracked through the drug development process, from initial dose finding to 2 confirmatory phase III trials. Varying the designs of the phase I, II, and III trials allows for an assessment of the effect of the choice of designs on the proportion of agents with successful phase III trials.

RESULTS

The results indicate that using the CRM or BOIN, rather than the 3+3, substantially enhances the proportion of effective agents that have successful phase III trials, with the CRM having a greater effect than BOIN. A larger phase II trial magnifies the effect of the phase I design.

CONCLUSIONS

The results underscore the importance of the choice of the early-phase designs. Use of the 3+3 results in fewer agents with successful phase III trials compared with the CRM or BOIN. The difference is more pronounced among highly effective agents. In addition, the results show the importance of a sufficiently powered phase II trial.

Shift models for dose-finding in partially ordered groups

BACKGROUND

Limited options are available for dose-finding clinical trials requiring group-specific dose selection. While conducting parallel trials for groups is an accessible approach to group-specific dose selection, this approach allows for maximum tolerated dose selection that does not align with clinically meaningful group order information.

METHODS

The two-stage continual reassessment method is developed for dose-finding in studies involving three or more groups where group frailty order is known between some but not all groups, creating a partial order. This is an extension of the existing continual reassessment method shift model for two ordered groups. This method allows for dose selection by group, where maximum tolerated dose selection follows the known frailty order among groups. For example, if a group is known to be the most frail, the recommended maximum tolerated dose for this group should not exceed the maximum tolerated dose recommended for any other group.

RESULTS

With limited alternatives for dose-finding in partially ordered groups, this method is compared to two alternatives: (1) an existing method for dose-finding in partially ordered groups which is less computationally accessible and (2) independent trials for each group using the two-stage continual reassessment method. Simulation studies show that when ignoring information on group frailty, using independent continual reassessment method trials by group, 30% of simulations would result in maximum tolerated dose selection that is out of order between groups. In addition, the two-stage continual reassessment method for partially ordered groups selects the maximum tolerated dose more often and assigns more patients to the maximum tolerated dose compared to using independent continual reassessment method trials within each group. Simulation results for the proposed method and the less computationally accessible approach are similar.

CONCLUSION

The proposed continual reassessment method for partially ordered groups ensures appropriate maximum tolerated dose order and improves accuracy of maximum tolerated dose selection, while allowing for trial implementation that is computationally accessible.

Revisiting isotonic phase I design in the era of model-assisted dose-finding

Background/aims In the conduct of phase I trials, the limited use of innovative model-based designs in practice has led to an introduction of a class of "model-assisted" designs with the aim of effectively balancing the trade-off between design simplicity and performance. Prior to the recent surge of these designs, methods that allocated patients to doses based on isotonic toxicity probability estimates were proposed. Like model-assisted methods, isotonic designs allow investigators to avoid difficulties associated with pre-trial parametric specifications of model-based designs. The aim of this work is to take a fresh look at an isotonic design in light of the current landscape of model-assisted methods. Methods The isotonic phase I method of Conaway, Dunbar, and Peddada was proposed in 2004 and has been regarded primarily as a design for dose-finding in drug combinations. It has largely been overlooked in the single-agent setting. Given its strong simulation performance in application to more complex dose-finding problems, such as drug combinations and patient heterogeneity, as well as the recent development of user-friendly software to accompany the method, we take a fresh look at this design and compare it to a current model-assisted method. We generated operating characteristics of the Conaway-Dunbar-Peddada method using a new web application developed for simulating and implementing the design and compared it to the recently proposed Keyboard design that is based on toxicity probability intervals. Results The Conaway-Dunbar-Peddada method has better performance in terms of accuracy of dose recommendation and safety in patient allocation in 17 of 20 scenarios considered. The Conaway-Dunbar-Peddada method also allocated fewer patients to doses above the maximum tolerated dose than the Keyboard method in many of scenarios studied. Overall, the performance of the Conaway-Dunbar-Peddada method is strong when compared to the Keyboard method, making it a viable simple alternative to the model-assisted methods developed in recent years. Conclusion The Conaway-Dunbar-Peddada method does not rely on the specification and fitting of a parametric model for the entire dose-toxicity curve to estimate toxicity probabilities as other model-based designs do. It relies on a similar set of pre-trial specifications to toxicity probability interval-based methods, yet unlike model-assisted methods, it is able to borrow information across all dose levels, increasing its efficiency. We hope this concise study of the Conaway-Dunbar-Peddada method, and the availability of user-friendly software, will augment its use in practice.

Validation of a simple disease-specific, quality-of-life measure for diabetic polyneuropathy: CAPPRI

OBJECTIVE

We studied the performance of a 15-item, health-related quality-of-life polyneuropathy scale in the clinic setting in patients with diabetic distal sensorimotor polyneuropathy (DSPN).

METHODS

Patients with DSPN from 11 academic sites completed a total of 231 Chronic Acquired Polyneuropathy Patient-Reported Index (CAPPRI) scales during their clinic visits. Conventional and modern psychometric analyses were performed on the completed forms.

RESULTS

Conventional and modern analyses generally indicated excellent psychometric properties of the CAPPRI in patients with DSPN. For example, the CAPPRI demonstrated unidimensionality and performed like an interval-level scale.

CONCLUSION

Attributes of the CAPPRI for DSPN include ease of use and interpretation; unidimensionality, allowing scores to be summed; adequate coverage of disease severity; and the scale's ability to address relevant life domains. Furthermore, the CAPPRI is free and in the public domain. The CAPPRI may assist the clinician and patient with DSPN in estimating disease-specific quality of life, especially in terms of pain, sleep, psychological well-being, and everyday function. The CAPPRI may be most useful in the everyday clinical setting but merits further study in this setting, as well as the clinical trial setting.

Focal adhesion kinase (FAK) deficiency in mononuclear phagocytes alters murine breast tumor progression

While it has long been recognized that mononuclear phagocytes play a significant role in determining breast tumor progression, the molecular factors that contribute to these events are not fully understood. In this report, we sought to determine whether focal adhesion kinase (FAK) expression in this cell population influences primary breast tumor initiation and growth. Using the MMTV-polyoma middle T (PyVmT) murine model of spontaneous breast cancer, we found that FAK expression in mononuclear phagocytes accelerates tumor initiation/progression during the early stages of PyVmT tumor growth but subsequently restricts tumor growth once the tumors have transitioned to malignancy. Mononuclear phagocytes accumulated at the site of developing tumors in a FAK-independent manner. However, once in the tumor, our data suggest that FAK expression is upregulated in the tumor-associated myeloid cells, and its activity in this population of cells may influence the immune landscape of the tumor by supporting the recruitment and/or survival of NK cells. Together, these data support a model in which FAK expression in the mononuclear phagocyte compartment positively regulates the early steps of tumor progression but subsequently functions to restrict tumor growth as the tumors transition to invasive carcinoma.

Early childhood growth and cognitive outcomes: Findings from the MAL-ED study

Although many studies around the world hope to measure or improve developmental progress in children to promote community flourishing and productivity, growth is sometimes used as a surrogate because cognitive skills are more difficult to measure. Our objective was to assess how childhood measures of anthropometry correlate with measures of child development in low-income settings with high prevalence of poor nutrition and enteric disease, to inform studies considering growth outcomes in the absence of direct child developmental skill assessment. Children from the MAL-ED study were followed from birth to 24 months of age in field sites in 8 low- and middle-income countries across 3 continents. Monthly weight, length, and head circumference measurements were performed. At 24 months, the Bayley Scales of Infant and Toddler Development was administered. We correlated cognitive measures at 24 months with anthropometric measurements from birth to 2 years comparing 3 constructs: absolute attained monthly measures, summative difference in measures from the mean growth curve, and rate of change in measures. Growth faltering at multiple time periods is related to Bayley cognitive outcomes at 24 months. Birthweight, overall growth by 18-24 months, and rate of growth in the 6- to 18-month period were most associated with 24-month developmental scores. In this study, head circumference measurements, compared with length, was more closely linked to cognitive scores at 24 months. Notably, all studies between growth and cognitive outcomes exhibited low r² values (0.001-0.049). Anthropometric measures, particularly head circumference, were related to cognitive development, although explaining a low percent of variance. When feasible, direct measures of child development may be more useful.

Implementation of a Model-Based Design in a Phase Ib Study of Combined Targeted Agents

In recent years, investigators have recognized the rigidity of single-agent, safety-only, traditional designs, rendering them ineffective for conducting contemporary early-phase clinical trials, such as those involving combinations and/or biological agents. Novel approaches are required to address these research questions, such as those posed in trials involving targeted therapies. We describe the implementation of a model-based design for identifying an optimal treatment combination, defined by low toxicity and high efficacy, in an early-phase trial evaluating a combination of two oral targeted inhibitors in relapsed/refractory mantle cell lymphoma. Operating characteristics demonstrate the ability of the method to effectively recommend optimal combinations in a high percentage of trials with reasonable sample sizes. The proposed design is a practical, early-phase, adaptive method for use with combined targeted therapies. This design can be applied more broadly to early-phase combination studies, as it was used in an ongoing study of a melanoma helper peptide vaccine plus novel adjuvant combinations. Clin Cancer Res; 23(23); 7158-64. ©2017 AACR.

Follow-up of Acute kidney injury in Neonates during Childhood Years (FANCY): a prospective cohort study

BACKGROUND

Very low birth weight (VLBW) neonates commonly experience acute kidney injury (AKI) in the neonatal intensive care unit (NICU). We hypothesize that VLBW neonates exposed to AKI in the NICU might be at a higher risk of renal dysfunction during childhood.

METHODS

In this cohort study, VLBW children (aged 3-7 years) completed a kidney health evaluation and were stratified according to AKI status in the NICU. The primary outcome was renal dysfunction defined as any of the following: estimated glomerular filtration rate (eGFR) <90 mL/min/1.73 m², urine protein/creatinine >0.2 or blood pressure ≥95th percentile.

RESULTS

Thirty-four subjects completed the study. Twenty subjects had a history of neonatal AKI (stage 1, n = 8; stage 2, n = 9; and stage 3, n = 3). At a median age of 5 years, the AKI group had a higher risk of renal dysfunction compared with the group without AKI (65% vs 14%, relative risk 4.5 (1.2-17.1), p = 0.01). Overall, 26% of the total cohort had an eGFR <90 mL/min/1.73 m² using serum cystatin C (35% of AKI subjects, 14% of no AKI subjects, p = 0.25).

CONCLUSIONS

Evidence of renal dysfunction in neonates born VLBW can be found early in childhood. Further work is necessary to determine how to reduce renal disease in this vulnerable population.

A design for phase I trials in completely or partially ordered groups

We propose a design for dose finding for cytotoxic agents in completely or partially ordered groups of patients. By completely ordered groups, we mean that prior to the study, there is clinical information that would indicate that for a given dose, the groups can be ordered with respect to the probability of toxicity at that dose. With partially ordered groups, at a given dose, only some of the groups can be ordered with respect to the probability of toxicity at that dose. The method we propose includes elements of the parametric model used in the continual reassessment method combined with the Hwang-Peddada order-restricted estimation procedure. We evaluate the operating characteristics of these designs in a family of dose-toxicity curves representing complete and partial orders. Copyright © 2017 John Wiley & Sons, Ltd.

Designs for phase I trials in ordered groups

We propose a new design for dose finding for cytotoxic agents in two ordered groups of patients. By ordered groups, we mean that prior to the study there is clinical information that would indicate that for a given dose one group would be more susceptible to toxicities than patients in the other group. The designs are evaluated relative to two previously proposed designs for ordered groups over a range of scenarios generated randomly from a family of dose-toxicity curves. Copyright © 2016 John Wiley & Sons, Ltd.

Dimension of model parameter space and operating characteristics in adaptive dose-finding studies

Adaptive, model-based, dose-finding methods, such as the continual reassessment method, have been shown to have good operating characteristics. One school of thought argues in favor of the use of parsimonious models, not modeling all aspects of the problem, and using a strict minimum number of parameters. In particular, for the standard situation of a single homogeneous group, it is common to appeal to a one-parameter model. Other authors argue for a more classical approach that models all aspects of the problem. Here, we show that increasing the dimension of the parameter space, in the context of adaptive dose-finding studies, is usually counter productive and, rather than leading to improvements in operating characteristics, the added dimensionality is likely to result in difficulties. Among these are inconsistency of parameter estimates, lack of coherence in escalation or de-escalation, erratic behavior, getting stuck at the wrong level, and, in almost all cases, poorer performance in terms of correct identification of the targeted dose. Our conclusions are based on both theoretical results and simulations. Copyright © 2016 John Wiley & Sons, Ltd.

Growth and development in children born very low birthweight

OBJECTIVE

To examine the relationships between growth (birth to age 2 years) and developmental outcomes in children born with very low birthweight (VLBW).

DESIGN

Motor and mental development in children born with VLBW were regressed on anthropometric measurements at birth, 9 months and 2 years using multivariable regression.

SETTING

The Early Childhood Longitudinal Study-Birth Cohort, a longitudinal cohort, community sample, designed to be representative of children born across the USA.

PATIENTS

950 children born with VLBW (<1500 g).

MAIN OUTCOME MEASURES

Motor and cognitive scores on the Bayley Scales at 9 months and 24 months chronological age.

RESULTS

A high proportion of children exhibited poor growth, with length-for-age z-scores <-2 (ie, stunting) in 21.3% of children at 9 months (adjusted for prematurity) and 34.2% of children at 2 years. Compared with children having z-scores >-2, children with growth shortfalls in head circumference, length and weight had a higher adjusted OR (aOR) of low Bayley motor scores at 9 months and 2 years (aOR ranging from 1.8 to 3.3, all p<0.05), while low Bayley cognitive scores were predicted by 9-month deficits in length and weight (aOR 2.0 and 2.4, respectively, both p<0.01) and 2-year deficits in length and head circumference (aOR 2.9 and 2.8, both p<0.05).

CONCLUSION

Anthropometric measures of growth were linked to current and future neurodevelopmental outcomes in children born with VLBW. While careful length measures may be a particularly useful marker, deficits in all anthropometric measures were risk factors for developmental delays.

Performance of toxicity probability interval based designs in contrast to the continual reassessment method

Toxicity probability interval designs have received increasing attention as a dose-finding method in recent years. In this study, we compared the two-stage, likelihood-based continual reassessment method (CRM), modified toxicity probability interval (mTPI), and the Bayesian optimal interval design (BOIN) in order to evaluate each method's performance in dose selection for phase I trials. We use several summary measures to compare the performance of these methods, including percentage of correct selection (PCS) of the true maximum tolerable dose (MTD), allocation of patients to doses at and around the true MTD, and an accuracy index. This index is an efficiency measure that describes the entire distribution of MTD selection and patient allocation by taking into account the distance between the true probability of toxicity at each dose level and the target toxicity rate. The simulation study considered a broad range of toxicity curves and various sample sizes. When considering PCS, we found that CRM outperformed the two competing methods in most scenarios, followed by BOIN, then mTPI. We observed a similar trend when considering the accuracy index for dose allocation, where CRM most often outperformed both mTPI and BOIN. These trends were more pronounced with increasing number of dose levels. Copyright © 2016 John Wiley & Sons, Ltd.

Combinatorial drug screening and molecular profiling reveal diverse mechanisms of intrinsic and adaptive resistance to BRAF inhibition in V600E BRAF mutant melanomas

Over half of BRAFV600E melanomas display intrinsic resistance to BRAF inhibitors, in part due to adaptive signaling responses. In this communication we ask whether BRAFV600E melanomas share common adaptive responses to BRAF inhibition that can provide clinically relevant targets for drug combinations. We screened a panel of 12 treatment-naïve BRAFV600E melanoma cell lines with MAP Kinase pathway inhibitors in pairwise combination with 58 signaling inhibitors, assaying for synergistic cytotoxicity. We found enormous diversity in the drug combinations that showed synergy, with no two cell lines having an identical profile. Although the 6 lines most resistant to BRAF inhibition showed synergistic benefit from combination with lapatinib, the signaling mechanisms by which this combination generated synergistic cytotoxicity differed between the cell lines. We conclude that adaptive responses to inhibition of the primary oncogenic driver (BRAFV600E) are determined not only by the primary oncogenic driver but also by diverse secondary genetic and epigenetic changes ("back-seat drivers") and hence optimal drug combinations will be variable. Because upregulation of receptor tyrosine kinases is a major source of drug resistance arising from diverse adaptive responses, we propose that inhibitors of these receptors may have substantial clinical utility in combination with inhibitors of the MAP Kinase pathway.

Construction and validation of the chronic acquired polyneuropathy patient-reported index (CAP-PRI): A disease-specific, health-related quality-of-life instrument

INTRODUCTION

Generic health-related quality-of-life (HRQOL) patient-reported outcome measures have been used in patients with chronic immune-mediated polyneuropathies. We have created a disease-specific HRQOL instrument.

METHODS

The chronic acquired polyneuropathy patient-reported index (CAP-PRI) was developed and validated in multiple steps. Items were initially generated through patient and specialist input. The performance of the preliminary 20 items was analyzed via a prospective, 5-center study involving chronic immune-mediated polyneuropathy patients.

RESULTS

Data analysis suggested modification to a 15-item scale with 3 response categories rather than 5. The final CAP-PRI was validated in another prospective, 5-center study. The CAP-PRI appeared to be a unidimensional outcome measure that fit the Rasch model in our multicenter cohort. It correlated appropriately with outcome measures commonly used in this patient population.

CONCLUSIONS

The CAP-PRI is a simple disease-specific HRQOL measure that appears to be useful for clinical care and possibly also for clinical trials. Muscle Nerve 54: 9-17, 2016.

Checkpoint Kinase 2 Negatively Regulates Androgen Sensitivity and Prostate Cancer Cell Growth

Prostate cancer is the second leading cause of cancer death in American men, and curing metastatic disease remains a significant challenge. Nearly all patients with disseminated prostate cancer initially respond to androgen deprivation therapy (ADT), but virtually all patients will relapse and develop incurable castration-resistant prostate cancer (CRPC). A high-throughput RNAi screen to identify signaling pathways regulating prostate cancer cell growth led to our discovery that checkpoint kinase 2 (CHK2) knockdown dramatically increased prostate cancer growth and hypersensitized cells to low androgen levels. Mechanistic investigations revealed that the effects of CHK2 were dependent on the downstream signaling proteins CDC25C and CDK1. Moreover, CHK2 depletion increased androgen receptor (AR) transcriptional activity on androgen-regulated genes, substantiating the finding that CHK2 affects prostate cancer proliferation, partly, through the AR. Remarkably, we further show that CHK2 is a novel AR-repressed gene, suggestive of a negative feedback loop between CHK2 and AR. In addition, we provide evidence that CHK2 physically associates with the AR and that cell-cycle inhibition increased this association. Finally, IHC analysis of CHK2 in prostate cancer patient samples demonstrated a decrease in CHK2 expression in high-grade tumors. In conclusion, we propose that CHK2 is a negative regulator of androgen sensitivity and prostate cancer growth, and that CHK2 signaling is lost during prostate cancer progression to castration resistance. Thus, perturbing CHK2 signaling may offer a new therapeutic approach for sensitizing CRPC to ADT and radiation.

Abstract 5049: Checkpoint kinase 2 is a novel regulator of prostate cancer cell growth

Prostate cancer (PCa) is the second leading cause of cancer death in American men, and the cure for metastatic disease remains a significant challenge. While nearly all patients with disseminated PCa initially respond to androgen deprivation therapy (ADT), virtually every patient will relapse and develop incurable castration-resistant prostate cancer (CRPC). Androgen receptor (AR) signaling pathways continue to play a crucial role in CRPC progression. Previous studies have shown that signal transduction pathways can stimulate AR activation, suggesting that the ability of signaling cascades to influence AR function may have a significant role in CRPC progression, and that CRPC may not be effectively treated by ligand-directed therapy alone. A high-throughput RNAi screen identifying signaling pathways that regulate PCa cell growth led to our discovery that knockdown of Checkpoint Kinase 2 (CHK2) dramatically increased PCa proliferation in the presence and absence of androgen. Furthermore, CHK2 depletion hypersensitized cells to castrate androgen levels. These CHK2-mediated effects on growth were dependent on the downstream signaling proteins CDC25C and CDK1 and could be blocked by the AR antagonist MDV3100. Immunohistochemical analysis of CHK2 in patient samples demonstrated that reduced CHK2 expression significantly correlated with increased Gleason score indicating the clinical relevance of CHK2 in PCa. Moreover, CHK2 expression is lower in castration-resistant C4-2 and CWR22Rv1 cells compared to androgen-sensitive LNCaP cells consistent with loss of CHK2 expression during PCa progression. CHK2 depletion increased AR transcriptional activity on both androgen-activated and androgen-repressed genes, substantiating that CHK2 affects PCa growth through the AR. Remarkably, quantitative PCR, chromatin immunoprecipitation, and western blot analyses revealed that CHK2 is a novel AR-repressed gene, suggesting a negative feedback loop between CHK2 and the AR. Furthermore, we show that CHK2 physically associates with the AR, and that cellular stress, such as DNA damage and serum starvation, increases this association. Based on these data, we propose that CHK2 is a negative regulator of androgen sensitivity and PCa growth. Thus, alterations to CHK2 signaling may sensitize CRPC to ADT and radiation.

Citation Format: Huy Q. Ta, Melissa L. Ivey, Henry F. Frierson, Mark R. Conaway, Jaroslaw Dziegielewski, James M. Larner, Daniel Gioeli. Checkpoint kinase 2 is a novel regulator of prostate cancer cell growth. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5049. doi:10.1158/1538-7445.AM2015-5049

Viewing as little as 1 hour of TV daily is associated with higher change in BMI between kindergarten and first grade

OBJECTIVE

Evaluate associations between TV viewing and weight status in children from kindergarten to first grade.

METHODS

Linear and logistic regression was used to evaluate associations of TV-viewing time on BMI-z-score cross-sectionally at kindergarten and first grade and longitudinally in between, among a nationally representative sample of 14,645 children from the Early Childhood Longitudinal Study-Kindergarten Cohort 2011. All analyses were adjusted for sex, race/ethnicity, parental education, and household income.

RESULTS

Weekday TV-viewing time was correlated with BMI-z-score (P < 0.01) at kindergarten and first grade and with change in BMI-z-score in between (P < 0.05). Compared with children watching <1 h of TV daily, children watching ≥1 h in kindergarten and first grade had a greater odds of overweight (1.50-1.60) and obesity (1.58-1.73). Children watching 1-<2 h and ≥2 h daily had higher BMI-z-scores (P < 0.0001) and less favorable changes in BMI-z-score between time points (P < 0.05). Children who were not overweight or obese in kindergarten and watched ≥1 h of TV had a greater odds of becoming overweight (1.39) and obese (1.86) between evaluations.

CONCLUSIONS

Children watching as little as 1-<2 h of TV daily were more likely to become overweight and obese over time. Physicians should encourage families to restrict TV-viewing time to reduce weight gain.