Leukemia cell proliferation and death in chronic lymphocytic leukemia patients on therapy with the BTK inhibitor ibrutinib

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Abstract

BACKGROUND. Ibrutinib is an effective targeted therapy for patients with chronic lymphocytic leukemia (CLL) that inhibits Bruton’s tyrosine kinase (BTK), a kinase involved in B cell receptor signaling.

METHODS. We used stable isotopic labeling with deuterated water (²H₂O) to measure directly the effects of ibrutinib on leukemia cell proliferation and death in 30 patients with CLL.

RESULTS. The measured average CLL cell proliferation (“birth”) rate before ibrutinib therapy was 0.39% of the clone per day (range 0.17%–1.04%); this decreased to 0.05% per day (range 0%–0.36%) with treatment. Death rates of blood CLL cells increased from 0.18% per day (average, range 0%–0.7%) prior to treatment to 1.5% per day (range 0%–3.0%) during ibrutinib therapy, and they were even higher in tissue compartments.

CONCLUSIONS. This study provides the first direct in vivo measurements to our knowledge of ibrutinib’s antileukemia actions, demonstrating profound and immediate inhibition of CLL cell proliferation and promotion of high rates of CLL cell death.

TRIAL REGISTRATION. This trial was registered at clinicaltrials.gov (NCT01752426).

FUNDING. This study was supported by a Cancer Center Support Grant (National Cancer Institute grant P30 CA016672), an NIH grant (CA081554) from the National Cancer Institute, MD Anderson’s Moon Shots Program in CLL, and Pharmacyclics, an AbbVie company.

Authors

Jan A. Burger, Kelvin W. Li, Michael J. Keating, Mariela Sivina, Ahmed M. Amer, Naveen Garg, Alessandra Ferrajoli, Xuelin Huang, Hagop Kantarjian, William G. Wierda, Susan O’Brien, Marc K. Hellerstein, Scott M. Turner, Claire L. Emson, Shih-Shih Chen, Xiao-Jie Yan, Dominik Wodarz, Nicholas Chiorazzi

Prostatic compensation of the vitamin D axis in African American men

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Abstract

BACKGROUND. African American (AA) men are disproportionately affected by both prostate cancer (PCa) and vitamin D deficiency compared with European American (EA) men. Vitamin D deficiency is linked to increased PCa aggressiveness and mortality. Therefore, it has been hypothesized that vitamin D deficiency may contribute to the PCa disparity between AA and EA men.

METHODS. We studied a cross sectional group of 60 PCa patients (AA, n = 31; EA, n = 29) who underwent radical prostatectomy. Vitamin D metabolites 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)₂D) were measured in the serum and tissue by uHPLC-MS-MS. Tissue was laser capture microdissected, and gene expression was quantified by microarray. DNA isolated from whole blood was genotyped for West African ancestry markers and vitamin D–related SNPs.

RESULTS. Serum concentrations of 25(OH)D were lower in AAs, but concentrations of 1,25(OH)₂D in the prostate tissue were higher compared with EAs. Expression of the vitamin D receptor was higher in prostate tissue from AAs. Expression of the extracellular receptor of vitamin D binding protein, LRP2, was positively associated with West African ancestry and inversely associated with tissue 25(OH)D concentrations in AAs.

CONCLUSIONS. The relationships between vitamin D binding protein LRP2 and vitamin D metabolites suggest that the prohormone is actively transported into the prostate, followed by intraprostatic conversion to the active hormone, rather than passive diffusion. These findings support the presence of a compensatory response in prostate tissue to vitamin D deficiency in AAs and reveal a previously unknown complexity involving tissue distribution of vitamin D metabolites.

FUNDING. Department of Defense Prostate Cancer Research Program Idea Award for Disparities Research PC121923 (LN and RK) and the NIH 1R01MD007105 (RK).

Authors

Zachary Richards, Ken Batai, Rachael Farhat, Ebony Shah, Andrew Makowski, Peter H. Gann, Rick Kittles, Larisa Nonn

Myocardial microRNAs associated with reverse remodeling in human heart failure

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Abstract

BACKGROUND. In dilated cardiomyopathies (DCMs) changes in expression of protein-coding genes are associated with reverse remodeling, and these changes can be regulated by microRNAs (miRs). We tested the general hypothesis that dynamic changes in myocardial miR expression are predictive of β-blocker–associated reverse remodeling.

METHODS. Forty-three idiopathic DCM patients (mean left ventricular ejection fraction 0.24 ± 0.09) were treated with β-blockers. Serial ventriculography and endomyocardial biopsies were performed at baseline, and after 3 and 12 months of treatment. Changes in RT-PCR (candidate miRs) or array-measured miRs were compared based on the presence (R) or absence (NR) of a reverse-remodeling response, and a miR-mRNA-function pathway analysis (PA) was performed.

RESULTS. At 3 months, 2 candidate miRs were selectively changed in Rs, decreases in miR-208a-3p and miR-591. PA revealed changes in miR-mRNA interactions predictive of decreased apoptosis and myocardial cell death. At 12 months, 5 miRs exhibited selective changes in Rs (decreases in miR-208a-3p, -208b-3p, 21-5p, and 199a-5p; increase in miR-1-3p). PA predicted decreases in apoptosis, cardiac myocyte cell death, hypertrophy, and heart failure, with increases in contractile and overall cardiac functions.

CONCLUSIONS. In DCMs, myocardial miRs predict the time-dependent reverse-remodeling response to β-blocker treatment, and likely regulate the expression of remodeling-associated miRs.

TRIAL REGISTRATION. ClinicalTrials.gov NCT01798992.

FUNDING. NIH 2R01 HL48013, 1R01 HL71118 (Bristow, PI); sponsored research agreements from Glaxo-SmithKline and AstraZeneca (Bristow, PI); NIH P20 HL101435 (Lowes, Port multi-PD/PI); sponsored research agreement from Miragen Therapeutics (Port, PI).

Authors

Carmen C. Sucharov, David P. Kao, J. David Port, Anis Karimpour-Fard, Robert A. Quaife, Wayne Minobe, Karin Nunley, Brian D. Lowes, Edward M. Gilbert, Michael R. Bristow

Protection against Plasmodium falciparum malaria by PfSPZ Vaccine

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Abstract

BACKGROUND: A radiation-attenuated Plasmodium falciparum (Pf) sporozoite (SPZ) malaria vaccine, PfSPZ Vaccine, protected 6 of 6 subjects (100%) against homologous Pf (same strain as in the vaccine) controlled human malaria infection (CHMI) 3 weeks after 5 doses administered intravenously. The next step was to assess protective efficacy against heterologous Pf (different from Pf in the vaccine), after fewer doses, and at 24 weeks.

METHODS: The trial assessed tolerability, safety, immunogenicity, and protective efficacy of direct venous inoculation (DVI) of 3 or 5 doses of PfSPZ Vaccine in non-immune subjects.

RESULTS: Three weeks after final immunization, 5 doses of 2.7 × 10⁵ PfSPZ protected 12 of 13 recipients (92.3% [95% CI: 48.0, 99.8]) against homologous CHMI and 4 of 5 (80.0% [10.4, 99.5]) against heterologous CHMI; 3 doses of 4.5 × 10⁵ PfSPZ protected 13 of 15 (86.7% [35.9, 98.3]) against homologous CHMI. Twenty-four weeks after final immunization, the 5-dose regimen protected 7 of 10 (70.0% [17.3, 93.3]) against homologous and 1 of 10 (10.0% [–35.8, 45.6]) against heterologous CHMI; the 3-dose regimen protected 8 of 14 (57.1% [21.5, 76.6]) against homologous CHMI. All 22 controls developed Pf parasitemia. PfSPZ Vaccine was well tolerated, safe, and easy to administer. No antibody or T cell responses correlated with protection.

CONCLUSIONS: We have demonstrated for the first time to our knowledge that PfSPZ Vaccine can protect against a 3-week heterologous CHMI in a limited group of malaria-naive adult subjects. A 3-dose regimen protected against both 3-week and 24-week homologous CHMI (87% and 57%, respectively) in this population. These results provide a foundation for developing an optimized immunization regimen for preventing malaria.

TRIAL REGISTRATION: ClinicalTrials.gov NCT02215707.

FUNDING: Support was provided through the US Army Medical Research and Development Command, Military Infectious Diseases Research Program, and the Naval Medical Research Center’s Advanced Medical Development Program.

Authors

Judith E. Epstein, Kristopher M. Paolino, Thomas L. Richie, Martha Sedegah, Alexandra Singer, Adam J. Ruben, Sumana Chakravarty, April Stafford, Richard C. Ruck, Abraham G. Eappen, Tao Li, Peter F. Billingsley, Anita Manoj, Joana C. Silva, Kara Moser, Robin Nielsen, Donna Tosh, Susan Cicatelli, Harini Ganeshan, Jessica Case, Debbie Padilla, Silas Davidson, Lindsey Garver, Elizabeth Saverino, Tooba Murshedkar, Anusha Gunasekera, Patrick S. Twomey, Sharina Reyes, James E. Moon, Eric R. James, Natasha KC, Minglin Li, Esteban Abot, Arnel Belmonte, Kevin Hauns, Maria Belmonte, Jun Huang, Carlos Vasquez, Shon Remich, Mary Carrington, Yonas Abebe, Amy Tillman, Bradley Hickey, Jason Regules, Eileen Villasante, B. Kim Lee Sim, Stephen L. Hoffman

Protein disulfide isomerase inhibition blocks thrombin generation in humans by interfering with platelet factor V activation

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Abstract

BACKGROUND: Protein disulfide isomerase (PDI) is required for thrombus formation. We previously demonstrated that glycosylated quercetin flavonoids such as isoquercetin inhibit PDI activity and thrombus formation in animal models, but whether extracellular PDI represents a viable anticoagulant target in humans and how its inhibition affects blood coagulation remain unknown.

METHODS: We evaluated effects of oral administration of isoquercetin on platelet-dependent thrombin generation in healthy subjects and patients with persistently elevated anti-phospholipid antibodies.

RESULTS: Following oral administration of 1,000 mg isoquercetin to healthy adults, the measured peak plasma quercetin concentration (9.2 μM) exceeded its IC₅₀ for inhibition of PDI by isoquercetin in vitro (2.5 ± 0.4 μM). Platelet-dependent thrombin generation decreased by 51% in the healthy volunteers compared with baseline (P = 0.0004) and by 64% in the anti-phospholipid antibody cohort (P = 0.015) following isoquercetin ingestion. To understand how PDI affects thrombin generation, we evaluated substrates of PDI identified using an unbiased mechanistic-based substrate trapping approach. These studies identified platelet factor V as a PDI substrate. Isoquercetin blocked both platelet factor Va and thrombin generation with an IC₅₀ of ~5 μM. Inhibition of PDI by isoquercetin ingestion resulted in a 53% decrease in the generation of platelet factor Va (P = 0.001). Isoquercetin-mediated inhibition was reversed with addition of exogenous factor Va.

CONCLUSION: These studies show that oral administration of isoquercetin inhibits PDI activity in plasma and diminishes platelet-dependent thrombin generation predominantly by blocking the generation of platelet factor Va. These pharmacodynamic and mechanistic observations represent an important step in the development of a novel class of antithrombotic agents targeting PDI.

TRIAL REGISTRATION: Clinicaltrials.gov (NCT01722669)

FUNDING: National Heart, Lung, and Blood Institute (U54 HL112302) and Quercegen Pharma

Authors

Jack D. Stopa, Donna Neuberg, Maneka Puligandla, Bruce Furie, Robert Flaumenhaft, Jeffrey I. Zwicker

Early cytokine signatures of ischemia/reperfusion injury in human orthotopic liver transplantation

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Abstract

BACKGROUND. Orthotopic liver transplant (OLT) is the primary therapy for end-stage liver disease and acute liver failure. However, ischemia/reperfusion injury (IRI) can severely compromise allograft survival. To understand the evolution of immune responses underlying OLT-IRI, we evaluated longitudinal cytokine expression profiles from adult OLT recipients before transplant through 1 month after transplant.

METHODS. We measured the expression of 38 cytokines, chemokines, and growth factors in preoperative and postoperative recipient circulating systemic blood (before transplant and 1 day, 1 week, and 1 month after transplant) and intraoperative portal blood (before and after reperfusion) of 53 OLT patients and analyzed this expression in relation to biopsy-proven IRI (n = 26 IRI+; 27 IRI–), clinical liver function tests early (days 1–7) after transplant, and expression of genes encoding cytokine receptors in biopsies of donor allograft taken before and after reperfusion.

RESULTS. Bilirubin and arginine transaminase levels early after transplant correlated with IRI. Fourteen cytokines were significantly increased in the systemic and/or portal blood of IRI+ recipients that shifted from innate to adaptive-immune responses over time. Additionally, expression of cognate receptors for 10 of these cytokines was detected in donor organ biopsies by RNAseq.

CONCLUSION. These results provide a mechanistic roadmap of the early immunological events both before and after IRI and suggest several candidates for patient stratification, monitoring, and treatment.

FUNDING. Ruth L. Kirschstein National Research Service Award T32CA009120, Keck Foundation award 986722, and a Quantitative & Computational Biosciences Collaboratory Postdoctoral Fellowship.

Authors

Rebecca A. Sosa, Ali Zarrinpar, Maura Rossetti, Charles R. Lassman, Bita V. Naini, Nakul Datta, Ping Rao, Nicholas Harre, Ying Zheng, Roberto Spreafico, Alexander Hoffmann, Ronald W. Busuttil, David W. Gjertson, Yuan Zhai, Jerzy W. Kupiec-Weglinski, Elaine F. Reed

Chorioretinal thinning in chronic kidney disease links to inflammation and endothelial dysfunction

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Abstract

BACKGROUND. Chronic kidney disease (CKD) is strongly associated with cardiovascular disease and there is an established association between vasculopathy affecting the kidney and eye. Optical coherence tomography (OCT) is a novel, rapid method for high-definition imaging of the retina and choroid. Its use in patients at high cardiovascular disease risk remains unexplored.

METHODS. We used the new SPECTRALIS OCT machine to examine retinal and retinal nerve fiber layer (RNFL) thickness, macular volume, and choroidal thickness in a prospective cross-sectional study in 150 subjects: 50 patients with hypertension (defined as a documented clinic BP greater than or equal to 140/90 mmHg (prior to starting any treatment) with no underlying cause identified); 50 with CKD (estimated glomerular filtration rate (eGFR) 8–125 ml/min/1.73 m²); and 50 matched healthy controls. We excluded those with diabetes. The same, masked ophthalmologist carried out each study. Plasma IL-6, TNF-α , asymmetric dimethylarginine (ADMA), and endothelin-1 (ET-1), as measures of inflammation and endothelial function, were also assessed.

RESULTS. Retinal thickness, macular volume, and choroidal thickness were all reduced in CKD compared with hypertensive and healthy subjects (for retinal thickness and macular volume P < 0.0001 for CKD vs. healthy and for CKD vs. hypertensive subjects; for choroidal thickness P < 0.001 for CKD vs. healthy and for CKD vs. hypertensive subjects). RNFL thickness did not differ between groups. Interestingly, a thinner choroid was associated with a lower eGFR (r = 0.35, P <0.0001) and, in CKD, with proteinuria (r = –0.58, P < 0.001) as well as increased circulating C-reactive protein (r = –0.57, P = 0.0002), IL-6 (r = –0.40, P < 0.01), ADMA (r = –0.37, P = 0.02), and ET-1 (r = –0.44, P < 0.01). Finally, choroidal thinning was associated with renal histological inflammation and arterial stiffness. In a model of hypertension, choroidal thinning was seen only in the presence of renal injury.

CONCLUSIONS. Chorioretinal thinning in CKD is associated with lower eGFR and greater proteinuria, but not BP. Larger studies, in more targeted groups of patients, are now needed to clarify whether these eye changes reflect the natural history of CKD. Similarly, the associations with arterial stiffness, inflammation, and endothelial dysfunction warrant further examination.

TRIAL REGISTRATION. Registration number at www.clinicalTrials.gov: NCT02132741.

SOURCE OF FUNDING. TR was supported by a bursary from the Erasmus Medical Centre, Rotterdam. JJMHvB was supported by a bursary from the Utrecht University. JRC is supported by a Rowling Scholarship. SB was supported by a Wellcome Trust funded clinical research fellowship from the Scottish Translational Medicine and Therapeutics Initiative, and by a Rowling Scholarship, at the time of this work. ND is supported by a British Heart Foundation Intermediate Clinical Research Fellowship (FS/13/30/29994).

Authors

Craig Balmforth, Job J.M.H. van Bragt, Titia Ruijs, James R. Cameron, Robert Kimmitt, Rebecca Moorhouse, Alicja Czopek, May Khei Hu, Peter J. Gallacher, James W. Dear, Shyamanga Borooah, Iain M. MacIntyre, Tom M.C. Pearson, Laura Willox, Dinesh Talwar, Muriel Tafflet, Christophe Roubeix, Florian Sennlaub, Siddharthan Chandran, Baljean Dhillon, David J. Webb, Neeraj Dhaun

Plasma vesicle miRNAs for therapy response monitoring in Hodgkin lymphoma patients

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Abstract

BACKGROUND. Cell-free circulating nucleic acids, including 22-nt microRNAs (miRNAs), represent noninvasive biomarkers for treatment response monitoring of cancer patients. While the majority of plasma miRNA is bound to proteins, a smaller, less well-characterized pool is associated with extracellular vesicles (EVs). Here, we addressed whether EV-associated miRNAs reflect metabolic disease in classical Hodgkin lymphoma (cHL) patients.

METHODS. With standardized size-exclusion chromatography (SEC), we isolated EV-associated extracellular RNA (exRNA) fractions and protein-bound miRNA from plasma of cHL patients and healthy subjects. We performed a comprehensive small RNA sequencing analysis and validation by TaqMan qRT-PCR for candidate discovery. Fluorodeoxyglucose-PET (FDG-PET) status before treatment, directly after treatment, and during long-term follow-up was compared directly with EV miRNA levels.

RESULTS. The plasma EV miRNA repertoire was more extensive compared with protein-bound miRNA that was heavily dominated by a few abundant miRNA species and was less informative of disease status. Purified EV fractions of untreated cHL patients and tumor EVs had enriched levels of miR24-3p, miR127-3p, miR21-5p, miR155-5p, and let7a-5p compared with EV fractions from healthy subjects and disease controls. Serial monitoring of EV miRNA levels in patients before treatment, directly after treatment, and during long-term follow-up revealed robust, stable decreases in miRNA levels matching a complete metabolic response, as observed with FDG-PET. Importantly, EV miRNA levels rose again in relapse patients.

CONCLUSION. We conclude that cHL-related miRNA levels in circulating EVs reflect the presence of vital tumor tissue and are suitable for therapy response and relapse monitoring in individual cHL patients.

FUNDING. Cancer Center Amsterdam Foundation (CCA-2013), Dutch Cancer Society (KWF-5510), Technology Foundation STW (STW Perspectief CANCER-ID).

Authors

Monique A.J. van Eijndhoven, Josée M. Zijlstra, Nils J. Groenewegen, Esther E.E. Drees, Stuart van Niele, S. Rubina Baglio, Danijela Koppers-Lalic, Hans van der Voorn, Sten F.W.M. Libregts, Marca H.M. Wauben, Renee X. de Menezes, Jan R.T. van Weering, Rienk Nieuwland, Lydia Visser, Anke van den Berg, Daphne de Jong, D. Michiel Pegtel

Institutional implementation of clinical tumor profiling on an unselected cancer population

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Abstract

BACKGROUND. Comprehensive genomic profiling of a patient’s cancer can be used to diagnose, monitor, and recommend treatment. Clinical implementation of tumor profiling in an enterprise-wide, unselected cancer patient population has yet to be reported.

METHODS. We deployed a hybrid-capture and massively parallel sequencing assay (OncoPanel) for all adult and pediatric patients at our combined cancer centers. Results were categorized by pathologists based on actionability. We report the results for the first 3,727 patients tested.

RESULTS. Our cohort consists of cancer patients unrestricted by disease site or stage. Across all consented patients, half had sufficient and available (>20% tumor) material for profiling; once specimens were received in the laboratory for pathology review, 73% were scored as adequate for genomic testing. When sufficient DNA was obtained, OncoPanel yielded a result in 96% of cases. 73% of patients harbored an actionable or informative alteration; only 19% of these represented a current standard of care for therapeutic stratification. The findings recapitulate those of previous studies of common cancers but also identify alterations, including in AXL and EGFR, associated with response to targeted therapies. In rare cancers, potentially actionable alterations suggest the utility of a “cancer-agnostic” approach in genomic profiling. Retrospective analyses uncovered contextual genomic features that may inform therapeutic response and examples where diagnoses revised by genomic profiling markedly changed clinical management.

CONCLUSIONS. Broad sequencing-based testing deployed across an unselected cancer cohort is feasible. Genomic results may alter management in diverse scenarios; however, additional barriers must be overcome to enable precision cancer medicine on a large scale.

FUNDING. This work was supported by DFCI, BWH, and the National Cancer Institute (5R33CA155554 and 5K23CA157631).

Authors

Lynette M. Sholl, Khanh Do, Priyanka Shivdasani, Ethan Cerami, Adrian M. Dubuc, Frank C. Kuo, Elizabeth P. Garcia, Yonghui Jia, Phani Davineni, Ryan P. Abo, Trevor J. Pugh, Paul van Hummelen, Aaron R. Thorner, Matthew Ducar, Alice H. Berger, Mizuki Nishino, Katherine A. Janeway, Alanna Church, Marian Harris, Lauren L. Ritterhouse, Joshua D. Campbell, Vanesa Rojas-Rudilla, Azra H. Ligon, Shakti Ramkissoon, James M. Cleary, Ursula Matulonis, Geoffrey R. Oxnard, Richard Chao, Vanessa Tassell, James Christensen, William C. Hahn, Philip W. Kantoff, David J. Kwiatkowski, Bruce E. Johnson, Matthew Meyerson, Levi A. Garraway, Geoffrey I. Shapiro, Barrett J. Rollins, Neal I. Lindeman, Laura E. MacConaill

Acute hemodynamic effects of inhaled sodium nitrite in pulmonary hypertension associated with heart failure with preserved ejection fraction

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Abstract

BACKGROUND. Pulmonary hypertension (PH) is associated with poor outcomes, yet specific treatments only exist for a small subset of patients. The most common form of PH is that associated with left heart disease (Group 2), for which there is no approved therapy. Nitrite has shown efficacy in preclinical animal models of Group 1 and 2 PH, as well as in patients with left heart failure with preserved ejection fraction (HFpEF). We evaluated the safety and efficacy of a potentially novel inhaled formulation of nitrite in PH-HFpEF patients as compared with Group 1 and 3 PH.

METHODS. Cardiopulmonary hemodynamics were recorded after acute administration of inhaled nitrite at 2 doses, 45 and 90 mg. Safety endpoints included change in systemic blood pressure and methemoglobin levels. Responses were also compared with those administered inhaled nitric oxide.

RESULTS. Thirty-six patients were enrolled (10 PH-HFpEF, 20 Group 1 pulmonary arterial hypertension patients on background PH-specific therapy, and 6 Group 3 PH). Drug administration was well tolerated. Nitrite inhalation significantly lowered pulmonary, right atrial, and pulmonary capillary wedge pressures, most pronounced in patients with PH-HFpEF. There was a modest decrease in cardiac output and systemic blood pressure. Pulmonary vascular resistance decreased only in Group 3 PH patients. There was substantial increase in pulmonary artery compliance, most pronounced in patients with PH-HFpEF.

CONCLUSIONS. Inhaled nitrite is safe in PH patients and may be efficacious in PH-HFpEF and Group 3 PH primarily via improvements in left and right ventricular filling pressures and pulmonary artery compliance. The lack of change in pulmonary vascular resistance likely may limit efficacy for Group 1 patients.

TRIAL REGISTRATION. ClinicalTrials.gov NCT01431313

FUNDING. This work was supported in part by the NIH grants 2P01HL103455 (to MAS and MTG), R01HL098032 (to MTG), and R01HL096973 (to MTG), and Mast Therapeutics, Inc.

Authors

Marc A. Simon, Rebecca R. Vanderpool, Mehdi Nouraie, Timothy N. Bachman, Pamela M. White, Masataka Sugahara, John Gorcsan III, Ed L. Parsley, Mark T. Gladwin