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Receptor-targeted image-guided Radionuclide Therapy (TRT) is increasingly recognized as a promising approach to cancer treatment. In particular, the potential for clinical translation of receptor-targeted alpha-particle therapy is receiving considerable attention as an approach that can improve outcomes for cancer patients. Higher Linear-energy Transfer (LET) of alpha-particles (compared to beta particles) for this purpose results in an increased incidence of double-strand DNA breaks and improved-localized cancer-cell damage. Recent clinical studies provide compelling evidence that alpha-TRT has the potential to deliver a significantly more potent anti-cancer effect compared with beta-TRT. Generator-produced 212Pb (which decays to alpha emitters 212Bi and 212Po) is a particularly promising radionuclide for receptor-targeted alpha-particle therapy. A second attractive feature that distinguishes 212Pb alpha-TRT from other available radionuclides is the possibility to employ elementallymatched isotope 203Pb as an imaging surrogate in place of the therapeutic radionuclide. As direct non-invasive measurement of alpha-particle emissions cannot be conducted using current medical scanner technology, the imaging surrogate allows for a pharmacologically-inactive determination of the pharmacokinetics and biodistribution of TRT candidate ligands in advance of treatment. Thus, elementally-matched 203Pb labeled radiopharmaceuticals can be used to identify patients who may benefit from 212Pb alpha-TRT and apply appropriate dosimetry and treatment planning in advance of the therapy. In this review, we provide a brief history on the use of these isotopes for cancer therapy; describe the decay and chemical characteristics of 203/212Pb for their use in cancer theranostics and methodologies applied for production and purification of these isotopes for radiopharmaceutical production. In addition, a medical physics and dosimetry perspective is provided that highlights the potential of 212Pb for alpha-TRT and the expected safety for 203Pb surrogate imaging. Recent and current preclinical and clinical studies are presented. The sum of the findings herein and observations presented provide evidence that the 203Pb/212Pb theranostic pair has a promising future for use in radiopharmaceutical theranostic therapies for cancer.

Simple Summary Radiation therapy and immune checkpoint inhibitors (ICIs) have been demonstrated to cooperatively activate adaptive anti-tumor immunity with curative potential in preclinical models of melanoma. Receptor-targeted radionuclide therapy can be systemically injected to selectively deliver ionizing radiation to tumor sites throughout the body, potentially rendering all tumor sites more susceptible to anti-tumor immune response. In this study, we demonstrated the feasibility of delivering alpha-particle radiation to murine melanoma tumors using a 212Pb radiolabeled peptide [212Pb]VMT01 that targets the melanocortin 1 receptor (MC1R). Our data showed anti-tumor cooperation between [212Pb]VMT01 and ICIs in melanoma, mediated by induction of tumor-specific immunity. The immunogenicity of [212Pb]VMT01 in melanoma was also evidenced by enhanced tumor infiltrating lymphocytes and tumor vaccination assays. Abstract Radiotherapy can facilitate the immune recognition of immunologically “cold” tumors and enhance the efficacy of anti-PD-1 and anti-CTLA-4 immune checkpoint inhibitors (ICIs) in melanoma. Systemic administration of receptor-targeted radionuclide therapy has the potential to selectively deliver radionuclides to multiple tumors throughout the body in metastatic settings. By triggering immunologic cell death and increasing the immune susceptibility of surviving tumor cells in these locations, targeted radionuclide therapies may overcome resistance to ICIs and render immunologically “cold” tumors throughout the body responsive to ICIs and immunologically “hot”. Here, we show the anti-tumor cooperation of targeted α-particle radionuclide therapy (α-TRT) and ICIs in preclinical models of melanoma. Melanocortin 1 receptor (MC1R)-targeted radiopeptide [212Pb]VMT01 was employed to deliver α-radiation to melanoma tumors in mice. A single injection of 4.1 MBq [212Pb]VMT01 significantly slowed the tumor growth of B16-F10 melanoma and the combination of [212Pb]VMT01 and ICIs induced a cooperative anti-tumor effect leading to 43% complete tumor response with no sign of malignancy on autopsy. Animals with complete response developed anti-tumor immunity to reject further tumor inoculations. This therapeutic cooperation was completely abolished in RAG1 KO mice, which are deficient in T-cell maturation. In addition, the anti-tumor cooperation was compromised when fractionated [212Pb]VMT01 was used in the combination. We also demonstrated that [212Pb]VMT01 induced immunogenic cell death in tumor vaccination assays and in vitro exposure to [212Pb]VMT01 sensitized immunotolerant melanoma to ICIs treatment in vivo. Enhanced tumor infiltrating CD3+, CD4+, CD8+ lymphocytes were observed following injection of 1.4 MBq [212Pb]VMT01. Overall, we demonstrated anti-tumor cooperation between α-TRT and ICIs in melanoma that is mediated by tumor specific immunity.

Melanocortin 1 receptor (MC1R) is under investigation as a target for drug delivery for metastatic melanoma therapy and imaging. The purpose of this study was to determine the potential of using BRAF inhibitors (BRAF(i)) and histone deacetylase inhibitors (HDAC(i)) to enhance the delivery of MC1R-targeted radiolabeled peptide ([(212)Pb]DOTA-MC1L) by pharmacologically upregulating the MC1R expression in metastatic melanoma cells and tumors. MC1R expression was analyzed in de-identified melanoma biopsies by immunohistochemical staining. Upregulation of MC1R expression was determined in BRAF(V600E) cells (A2058) and BRAF wild-type melanoma cells (MEWO) by quantitative real-time polymerase chain reaction, flow cytometry, and receptor-ligand binding assays. The role of microphthalmia-associated transcription factor (MITF) in the upregulation of MC1R was also examined in A2058 and MEWO cells. The effectiveness of [(212)Pb]DOTA-MC1L α-particle radiotherapy in combination with BRAF(i) and/or HDAC(i) was determined in athymic nu/nu mice bearing A2058 and MEWO human melanoma xenografts. High expression of MC1R was observed in situ in clinical melanoma biopsies. BRAF(i) and HDAC(i) significantly increased the MC1R expression (up to 10-fold in mRNA and 4-fold in protein levels) via MITF-dependent pathways, and this increase led to enhanced ligand binding on the cell surface. Inhibition of MITF expression antagonized the upregulation of MC1R in both BRAF(V600E) and BRAF(WT) cells. Combining [(212)Pb]DOTA-MC1L with BRAF(i) and/or HDAC(i) improved the tumor response by increasing the delivery of (212)Pb α-particle emissions to melanoma tumors via augmented MC1R expression. These data suggest that FDA-approved HDAC(i) and BRAF(i) could improve the effectiveness of MC1R-targeted therapies by enhancing drug delivery via upregulated MC1R.

The benefit of cardiac resynchronization therapy in patients supported by a left ventricular assist device (LVAD) is unknown. There are currently no guidelines regarding the continuation, discontinuation or pacemaker (PM) settings post-LVAD implant. The aim of the study was to assess the hemodynamic benefit of biventricular (BiV) pacing in LVAD patients. We studied 22 patients supported by LVADs (age 62 ± 9, 21 males) who had received a BiV PM before LVAD implant. A total of 123 complete sets of hemodynamics were obtained during BiV pacing (n = 54), right ventricular (RV) pacing (n = 54), and intrinsic rhythm (n = 15). There were no significant differences in right atrial (RA) pressure, mean pulmonary artery pressure (mPA), PCWP, cardiac output, PA saturation (PASat) and right ventricular stroke work index between BiV and RV pacing. Hemodynamics obtained during intrinsic rhythm in 15 non–PM-dependent patients were not significantly different compared with those obtained during BiV or RV pacing. Furthermore, hemodynamics were similar at different heart rates ranging 50 to 110 beats/min. Right ventricular stroke work index was significantly lower at the highest heart rate compared with baseline and lowest heart rates suggesting decreased RV performance at higher heart rate. In conclusion, BiV pacing does not have any acute hemodynamic benefit compared with RV pacing or intrinsic rhythm in LVAD patients. A lower heart rate may confer better RV performance.

In as little as six weeks, melanoma can turn life-threatening. Not only is melanoma a fast growing skin cancer, but its annual incidence rate is nearly 100,000 in the United States. Disease identified early can be cured by surgery, but metastatic melanoma is lethal. Despite the striking progress in treating metastatic melanoma using MAPK inhibitors and immune checkpoint inhibitors, improvements in objective response rate ( Citation Format: Brenna Marks, Mengshi Li, Edwin Sagastume, Michael Schultz, Frances Johnson. Assessing Melanocortin 1 receptor as a target for metastatic melanoma drug delivery [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1171.

Oncology nurse practitioner (ONP) patient navigators may improve clinical outcomes. However, no standard measures of the process of oncology patient navigation or of related clinical outcomes exist, and research in this area is limited. The exploratory pilot study detailed in this article used grounded theory and interviews with three ONPs to define the processes employed by ONP patient navigators in caring for patients with cancer. .

Who wants a left ventricular assist device for ambulatory heart failure? Early insights from the MEDAMACS screening pilot Garrick C. Stewart, MD, MPH, Michelle M. Kittleson, MD, PhD, Jennifer A. Cowger, MD, Frances L. Johnson, MD, Chetan B. Patel, MD, Maria M. Mountis, DO, Parag C. Patel, MD, J. Eduardo Rame, MD, Jeffrey Testani, MD, Maya E. Guglin, MD, Jeffrey J. Teuteberg, MD, and Lynne W. Stevenson, MD From the Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, Massachusetts; Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California; Cardiovascular Center, University of Michigan, Ann Arbor, Michigan; Division of Cardiology, University of Iowa, Iowa City, Iowa; Division of Cardiology, Duke University, Durham, North Carolina; Division of Cardiology, Cleveland Clinic Foundation, Cleveland, Ohio; Division of Cardiology, University of Texas Southwestern, Dallas, Texas; Heart and Vascular Center, University of Pennsylvania, Philadelphia, Pennsylvania; Division of Cardiology, University of South Florida, Tampa, Florida; and the Heart and Vascular Institute, University of Pittsburgh, Pittsburgh, Pennsylvania

Background Nurse practitioners should become more active in patient navigation and its subcomponent, care coordination, because research has shown that these roles are influential in improving patient care at all levels of an organization. Well-defined process and outcome measures, as well as educational initiatives, are critical to these programs because they serve as the structure for program evaluation. Objectives This article aims to assess and define metrics that nurse practitioners in the oncology setting can use to evaluate navigation programs, which is essential for the evolution of research pertaining to the navigation field. Methods The current article is a systematic review that describes oncology nurse practitioner navigation metrics using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) format for the systematic literature review process. These metrics are then compared to current standards of care. Findings Seven studies met the criteria for this review. Research is emerging that shows benefit in using an oncology nurse practitioner navigator for ensuring timely care and patient and staff satisfaction. These metrics are in line with expert consensus recommendations. The need for more research identifying sound research tools that have been rigorously tested has been identified.

A method for preparation of Pb-212 and Pb-203 labeled chelator-modified peptide-based radiopharmaceuticals for cancer imaging and radionuclide therapy has been developed and adapted for automated clinical production. Pre-concentration and isolation of radioactive Pb2+ from interfering metals in dilute hydrochloric acid was optimized using a commercially-available Pb-specific chromatography resin packed in disposable plastic columns. The pre-concentrated radioactive Pb2+ is eluted in NaOAc buffer directly to the reaction vessel containing chelator-modified peptides. Radiolabeling was found to proceed efficiently at 85 °C (45 min; pH 5.5). The specific activity of radiolabeled conjugates was optimized by separation of radiolabeled conjugates from unlabeled peptide via HPLC. Preservation of bioactivity was confirmed by in vivo biodistribution of Pb-203 and Pb-212 labeled peptides in melanoma-tumor-bearing mice. The approach has been found to be robustly adaptable to automation and a cassette-based fluid-handling system (Modular Lab Pharm Tracer) has been customized for clinical radiopharmaceutical production. Our findings demonstrate that the Pb-203/Pb-212 combination is a promising elementally-matched radionuclide pair for image-guided radionuclide therapy for melanoma, neuroendocrine tumors, and potentially other cancers.

Background— Cardiac dysfunction in failing hearts of human patients and animal models is associated with both microtubule densification and transverse-tubule (T-tubule) remodeling. Our objective was to investigate whether microtubule densification contributes to T-tubule remodeling and excitation–contraction coupling dysfunction in heart disease. Methods and Results— In a mouse model of pressure overload–induced cardiomyopathy by transaortic banding, colchicine, a microtubule depolymerizer, significantly ameliorated T-tubule remodeling and cardiac dysfunction. In cultured cardiomyocytes, microtubule depolymerization with nocodazole or colchicine profoundly attenuated T-tubule impairment, whereas microtubule polymerization/stabilization with taxol accelerated T-tubule remodeling. In situ immunofluorescence of heart tissue sections demonstrated significant disorganization of junctophilin-2 (JP2), a protein that bridges the T-tubule and sarcoplasmic reticulum membranes, in transaortic banded hearts as well as in human failing hearts, whereas colchicine injection significantly preserved the distribution of JP2 in transaortic banded hearts. In isolated mouse cardiomyocytes, prolonged culture or treatment with taxol resulted in pronounced redistribution of JP2 from T-tubules to the peripheral plasma membrane, without changing total JP2 expression. Nocodazole treatment antagonized JP2 redistribution. Moreover, overexpression of a dominant-negative mutant of kinesin 1, a microtubule motor protein responsible for anterograde trafficking of proteins, protected against JP2 redistribution and T-tubule remodeling in culture. Finally, nocodazole treatment improved Ca 2+ handling in cultured myocytes by increasing the amplitude of Ca 2+ transients and reducing the frequency of Ca 2+ sparks. Conclusion— Our data identify a mechanistic link between microtubule densification and T-tubule remodeling and reveal microtubule-mediated JP2 redistribution as a novel mechanism for T-tubule disruption, loss of excitation–contraction coupling, and heart failure.

Visual scoring of biomarkers by immunohistochemistry (IHC) on formalin-fixed paraffin embedded tissues constitutes a major part of histopathologic diagnosis and staging of several cancers. To improve sensitivity and linearity of IHC methods, we have developed a quantitative IHC technique using streptavidin coated phosphor integrated dot (PID) fluorescent nanoparticles (Gonda et al, Scientific Reports, 2017). In retrospective analysis of clinically established biomarkers (i.e., PD-L1, HER2, CSF-1R), IHC-PID has provided high-sensitivity quantitative detection of target proteins with a broad dynamic range. The present study examines the utility of IHC-PID in the biomarker discovery and validation process by evaluating melanocortin subtype 1 receptor (MC1R) in cell lines and clinical biopsy samples. MC1R is currently under investigation as a potential diagnostic and therapeutic target for malignant melanoma, a lethal cancer with poor long-term prognosis. MC1R is an endocytic cell-surface G-protein coupled receptor that exhibits relatively high expression in malignant melanoma tumors vs. normal tissues. Notably, current melanoma therapies, including MAPKi (e.g., vemurafenib, dabrafenib) increase MC1R expression pharmacologically on melanoma cells (unpublished results). MC1R expression was determined in cell lines by standard radio-ligand binding assay (125I-NDP-α-MSH). The SK-Mel-28 cell line showed 5-6 fold increased expression of endogenous MC1R when compared to the A375 cell line. Formalin fixed pellets of these two cell lines were used for analytical validation of PID-IHC. By utilizing dedicated image-processing algorithms, the readout of average PID score/cell was determined to be 285 and 98, for SK-Mel-28 and A375 cell lines, respectively. To confirm the increase in sensitivity with the PID technology, enabling quantitative IHC and improved detection of MC1R, de-identified melanoma samples from varying sites were collected by surgical biopsy at The University of Iowa Hospitals and Clinics and scored by a pathologist. Sister sections were stained by conventional IHC or IHC-PID. For IHC-PID, sections were counter stained by hematoxylin; tumor regions were hand annotated by a pathologist; and fluorescent images in 5 microscopic fields were captured and analyzed. Background PID threshold was determined by using no-primary antibody as controls. IHC-PID was performed on MS0759 (T1b N0 M0), MS0045 (T3a N1a M0) and MS0868 (T4b N3 M1a) samples and showed average PID score/cell of 217±38, 68±12, and 160±21, respectively. Ongoing studies are expanding on IHC-PID use to assess MC1R expression on a clinical melanoma panel (n=20) in late stage patients undergoing pharmacological interventions including MAPKi. The overall goal of this project is to develop PID-based quantitative IHC to support the development of MC1R as an imaging biomarker for patient stratification and monitoring clinical response to MC1R-targeted radionuclide therapy for malignant melanoma. Note: This abstract was not presented at the meeting. Citation Format: Apollina Goel, Kenji Nishikawa, Etsuko Futaya, Ildiko Poylak, Robert Holt, Mengshi Li, Edwin Sagastum, Brenna Marks, Aaron D. Bossler, Frances L. Johnson, Michael K. Schultz, Hideki Goda, Hisatake Okada, Kelly Orcutt, George Abe, Kenneth Bloom. Quantitative immunohistochemistry for melanocortin 1 receptor using phosphor integrated dots [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-230.

Background— INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) profiles provide important prognostic information for patients with advanced heart failure (HF) receiving mechanical support. The value of INTERMACS profiling has not been shown for patients followed on medical therapy for advanced HF at centers that also offer mechanical circulatory support. Methods and Results— This prospective, observational study enrolled 166 patients with chronic New York Heart Association class III–IV HF, ejection fraction ≤30%, and ≥1 HF hospitalization in the previous year, excluding patients listed for transplant or receiving chronic intravenous inotropic therapy. Subjects were followed for at least 12 months or until death, mechanical support, or transplant. Baseline features, quality of life, and outcomes were compared according to INTERMACS profile. Mean age was 57 years, ejection fraction 18%, and 57% had HF >5 years, whereas 23% of subjects were INTERMACS profile 4, 32% profile 5, and 45% profile 6/7. At 1 year, only 47% of this ambulatory advanced HF cohort remained alive on medical therapy. Patients in INTERMACS profile 4 were more likely to die or require mechanical support, with only 52% of these patients alive without support after the first 6 months. Profile 6/7 patients had 1-year survival of 84%, similar to outcomes for contemporary destination left ventricular assist device recipients. Quality of life using the indexed EuroQol score was poor across profiles 4 to 7, although severe limitation was less common than for ambulatory patients enrolled in INTERMACS before ventricular assist device implantation. Conclusions— Ambulatory patients with systolic HF, a heavy symptom burden, and at least 1 recent HF hospitalization are at high risk for death or left ventricular assist device rescue. INTERMACS profiles help identify ambulatory patients with advanced HF who may benefit from current mechanical support devices under existing indications.

The aim of this study was to determine the impact of prolonged left ventricular assist device (VAD) support on cardiac ventricular geometry and VAD flow kinetics.Nineteen patients with end-stage heart failure underwent the implantation of HeartMate II rotary flow VADs. Left and right ventricular geometry and VAD flow kinetics were assessed by transthoracic echocardiography early (7 ± 1 days) and late (113 ± 21 days) after VAD implantation.Left ventricular end-diastolic internal dimension decreased by 21% and 35%, respectively, early and late after VAD implantation (n = 19; P.001 vs before VAD implantation). Right ventricular end-diastolic internal dimension did not decrease at either time. Hemodynamic trends were similar. VAD inflow obstruction by myocardium was observed in eight patients, seven of whom demonstrated significantly increased variation of VAD inflow during the cardiac cycle ("pulsatility") detected by Doppler studies. Medical or surgical intervention returned VAD flow patterns toward baseline in seven of eight patients with VAD obstructions.Prolonged rotary VAD support unloads the left ventricle, with modest effects on the right ventricle. These changes are often associated with alterations of VAD flow kinetics, requiring therapeutic intervention. These findings indicate the usefulness of echocardiographic surveillance in patients undergoing prolonged VAD support.

Mutations that disrupt the coding sequence of Nav1.5, the cardiac Na+ channel encoded by SCN5A, cause inherited arrhythmias and cardiomyopathy. Changes in Nav1.5 splice isoforms, localization and function have also been associated with prognosis in acquired heart disease. However, the role of genetic variants in SCN5A gene regulatory sequences (e.g. those modulating expression) remains poorly understood. MicroRNAs (miRs) have emerged as vital gene regulators in heart, having roles in cardiogenesis, contractile function, and disease. These small non-coding RNAs are loaded into Argonaute proteins to direct post-transcriptional gene suppression by base-pairing with target transcripts, and genetic variants altering miR binding sequences may influence disease. Here, we used high-throughput biochemical means (HITS-CLIP) to generate the first transcriptome-wide map of miR binding events in human heart (4000 sites across >2200 genes). Our query of the data uncovered >500 common SNPs residing in or nearby miR target sites. Among these, we identified a synonymous SNP (rs1805126, T/C) which alters a conserved miR-24 binding site in the terminal coding exon of SCN5A. We hypothesized that this SNP affects Nav1.5 expression and contributes to clinical outcomes in heart failure. In vitro experiments showed that miR-24 suppresses Na+ current on patch clamp analysis (~5-fold; p1800 subjects with EFs≤30% and implantable cardioverter defibrillators (ICDs) from GRADE, a prospective multicenter study of genetic modulators of heart failure outcomes. We found that CC homozygotes had worse survival rates than T-allele carriers (HR=1.5, p=0.001), but no change in appropriate ICD shocks, a surrogate for sudden death. Together, these data reveal a novel miR-24:SCN5A:SNP regulatory axis that points to a surprising link between cardiac Na+ channel levels and non-arrhythmic death in heart failure. Overall, this work represents a key advance in exploring the interface of cardiac miRs with genetics and disease, perhaps signifying a broader functional relevance for “silent” SNPs.

Junctophilin-2 (JP2), a membrane-binding protein that provides a structural bridge between the plasmalemma and sarcoplasmic reticulum, is essential for precise Ca(2+)-induced Ca(2+) release during excitation-contraction coupling in cardiomyocytes. In animal and human failing hearts, expression of JP2 is decreased markedly, but the molecular mechanisms underlying JP2 down-regulation remain incompletely defined. In mouse hearts, ischemia/reperfusion injury resulted in acute JP2 down-regulation, which was attenuated by pretreatment with the calpain inhibitor MDL-28170 or by transgenic overexpression of calpastatin, an endogenous calpain inhibitor. Using a combination of computational analysis to predict calpain cleavage sites and in vitro calpain proteolysis reactions, we identified four putative calpain cleavage sites within JP2 with three N-terminal and one C-terminal cleavage sites. Mutagenesis defined the C-terminal region of JP2 as the predominant calpain cleavage site. Exogenous expression of putative JP2 cleavage fragments was not sufficient to rescue Ca(2+) handling in JP2-deficient cardiomyocytes, indicating that cleaved JP2 is non-functional for normal Ca(2+)-induced Ca(2+) release. These data provide new molecular insights into the posttranslational regulatory mechanisms of JP2 in cardiac diseases.

The dramatic efficacy of cardiac replacement therapy, an expanding population of potential recipients, and a shrinking donor supply have converged to create thorny medical and ethical issues for practitioners and patients. Based on scientific evaluation of current practice, new policies are being considered to optimize outcomes for end-stage heart failure patients in an equitable way. Meanwhile, improving efficacy of mechanical assist devices may soon justify transitioning from "bridge-to-transplant" to "destination therapy" as a standard approach for those who cannot safely await a transplant, further altering the landscape of surgical therapy for end stage heart failure. In this review, selected aspects of heart transplantation of interest to the broader transplant community are briefly reviewed, focusing on recipient and donor selection, surgical considerations, and subsequent management.

Del1 is a unique αvβ3 integrin ligand that is produced by endothelial cells, and thus provides an autocrine signaling pathway in this cell type. It is expressed transiently in the embryo and mediates cell attachment, migration, and activation of cytoplasmic signaling molecules in focal contacts. Del1 also activates angiogenesis in the chick chorioallantoic membrane assay. Reexpression of this embryonic signaling molecule has now been documented in naturally occurring human tumors, where it is expressed by both tumor cells and angiogenic endothelial cells, suggesting that Del1 is important in mediating angiogenesis under pathophysiological conditions in the adult. To investigate the role of Del1 in tumor growth and angiogenesis, human 143B osteosarcoma cells and murine Lewis lung carcinoma cells were engineered to express Del1 and compared to control transfectants for their ability to produce tumors in nude or syngeneic mice, respectively. Del1 expressing tumors showed a two- to fourfold increase in capillary density and an accelerated rate of growth. Expression of Del1 also correlated with a decrease in apoptosis in tumor cells in vivo. Taken together, these data suggest that Del1 acts as an angiogenic factor in the context of solid tumor formation and that this increase in vascularization accelerates tumor growth through decreased apoptosis.

Angiostatin and endostatin are potent endothelial cell growth inhibitors that have been shown to inhibit angiogenesis in vivo and tumor growth in mice. However, tumor shrinkage requires chronic delivery of large doses of these proteins. Here we report synergistic antitumor activity and survival of animals when these factors are delivered in combination to tumors by retroviral gene transfer. We have demonstrated this efficacy in both murine leukemia and melanoma models. Complete loss of tumorigenicity was seen in 40% of the animals receiving tumors transduced by the combination of angiostatin and endostatin in the leukemia model. The synergy was also demonstrated in vitro on human umbilical vein endothelial cell differentiation and this antiangiogenic activity may suggest a mechanism for the antitumor activity in vivo. These findings imply separate pathways by which angiostatin and endostatin mediate their antiangiogenic effects. Together, these data suggest that a combination of antiangiogenic factors delivered by retroviral gene transfer may produce synergistic antitumor effects in both leukemia and solid tumors, thus avoiding long-term administration of recombinant proteins. The data also suggest that novel combinations of antiangiogenic factors delivered into tumors require further investigation as therapeutic modalities.

Persistent severe left ventricular dysfunction during extracorporeal membrane oxygenation (ECMO) requires left heart decompression. We describe stenting of the atrial septum as an alternative emergency approach for left heart decompression during ECMO in addition to the already published surgical and transcatheter approaches.

A 43-year-old woman underwent mitral valve replacement for severe mitral regurgitation nine years after orthotopic heart transplant. Histopathology showed chronic rejection of the mitral valve with lymphocytic infiltrates. The patient is well at one year follow-up. This report describes an identified case of chronic mitral valve rejection requiring valve replacement.

The unique syndrome of brain death is associated with cardiac dysfunction; however, if such a heart is removed from this environment and transplanted, the cardiac dysfunction often resolves. This scenario offers insight into the mechanisms of reversible forms of cardiac injury and suggests that treatment of the extra-cardiac milieu by removing the initiating insult can often result in recovery. The mechanisms leading to reversible cardiac dysfunction are discussed in this review, with concentration on the implications of such injury in determining outcomes following transplantation.

Heart failure is a clinical syndrome that is heterogeneous in both pathophysiology and etiology. This article describes some of the common mechanisms underlying heart failure, and reviews common causes. Informative diagnostic testing is reviewed.

A 32-year-old man was referred to our medical center for chest pain and dyspnea of 2 days duration. Past medical history was unremarkable. Vital signs and physical examination were normal. ECG (Figure 1) showed a right bundle-branch block but no changes suggestive of ischemia. Troponin T level was 4.01 ng/mL (normal

The need to assess heart failure at an early stage highlights the importance of accurate microarray analysis using small tissue samples. To test our ability to obtain high quality RNA from biopsy-sized cardiac specimens, amplification was performed on RNA from biopsy-sized samples of left ventricle (LV) tissue from one explanted failing human heart and one non-failing heart. Two methods were used: one-cycle (1C) amplification of 1.6 microg of RNA, and two-cycle (2C) amplification of 50 ng of RNA. The resulting cRNA was hybridized to Affymetrix GeneChip arrays. Over 65% of all differentially expressed genes for failing vs non-failing hearts were concordant between 1C and 2C RNA amplification. Differentially expressed genes between 1C and 2C RNA amplification in our study were highly correlated (R(2) = 0.957 and changes in gene expression agreed with prior studies on genes and heart failure; e.g., decreased alpha-myosin heavy chain and alpha-tropomyosin, as well as increased expression of insulin-like growth factor). Two cycles of amplification from cardiac biopsies will permit accurate transcription profiling of heart failure at pre-symptomatic stages. Ability to measure gene expression from nanogram amounts of RNA will provide new opportunities to predict progression to symptomatic heart failure, and to identify potential targets for therapy.

Background Despite concerns about the adequacy of support provided by continuous-flow left ventricular assist devices (LVADs), direct comparisons of patient characteristics and outcomes between first-generation pulsatile and second-generation nonpulsatile LVADs are absent. We hypothesized that a nonpulsatile Jarvik 2000 LVAD (Jarvik Heart, Inc, New York, NY) would result in comparable outcomes to those of similarly ill patients implanted with a pulsatile LVAD (Novacor, WorldHeart Inc, Oakland, CA; and HeartMate XVE, Thoratec, Pleasanton, CA). Methods We retrospectively compared common pre-LVAD clinical characteristics and indicators of heart failure severity between 13 pulsatile and 14 nonpulsatile LVAD recipients. The outcomes analyzed were either heart transplantation, if the LVAD was intended as a bridge to transplantation, or hospital discharge if the intention was destination therapy. Results There was no significant difference between groups in pre-LVAD disease severity indicators. Nonpulsatile LVAD recipients had a significantly smaller body surface area (1.9 ± 0.2 m 2 versus 2.1 ± 0.2 m 2 , p = 0.04) and cardiopulmonary bypass time was also significantly shorter (61 ± 34 minutes versus 110 ± 49 minutes, p = 0.01). Aside from duration of initial intensive care unit stay (nonpulsatile, 10 ± 16 days; pulsatile, 14 ± 11 days; p = 0.02), there was no difference in post-LVAD outcomes: 10 of 14 nonpulsatile and 8 of 13 pulsatile LVAD patients achieved the combined end point ( p = 0.69). Conclusions Similarly ill congestive heart failure patients benefited equally well from either a nonpulsatile or a pulsatile LVAD. This may support an expanded role for nonpulsatile LVADs in the treatment of severe heart failure.

Purpose Ventricular assist devices (VAD) and heart transplantation (OHT) improve survival and quality of life in highly-selected patients, but the thresholds for considering ambulatory patients for advanced therapies remains unclear. The purpose of this study was to compare the characteristics and outcomes of patients at referral centers based on their median wait time to OHT. Methods and Materials The MedaMACS Screening Pilot Study enrolled patients from 10 US advanced heart failure centers, including those with INTERMACS profiles 4-7, EF ≤ 30%, and ≥1 heart failure hospitalization in the past year. Patients were divided based on the median wait time to OHT for Status 1A patients in their region: Group 1, ≤ 30 days, and Group 2, > 30 days. Clinical characteristics and outcomes were compared. Results Of 168 MedaMACS patients, 47 (28%) were in Group 1 and 121 (72%) were in Group 2. There was no difference in demographic or clinical characteristics, including symptoms, signs, echocardiographic or hemodynamic parameters. There were significantly more patients evaluated for OHT in Group 1 (53%) vs Group 2 (28%; p Table ). Conclusions Triage for advanced heart failure therapies at US centers appears to be driven by geography: centers with shorter median wait time to OHT are more likely to evaluate patients for OHT and less likely to place VADs. As patients at these different centers do not differ clinically, further study is needed to assess whether threshold for considering patients for advanced therapies should be determined by wait time to transplant as well as clinical considerations. Median wait time to transplant in the region for Status 1A patients in the region Group 1: ≤30 days (N = 48) Group 2: >30 days (N = 121) Death 15% (7) 22% (26) Transplantation * 25% (12) 7% (8) VAD * 2% (1) 18% (21) * p

Purpose Right atrial (RA) and pulmonary capillary wedge pressure (PCWP) are concordant in the majority of heart failure (HF) patients, allowing estimation of volume status by jugular venous pressure (JVP). Pts with discordant filling pressures have been identified while undergoing transplant evaluation. However, the incidence and outcomes of discordant filling pressures have not been evaluated in pts with chronic advanced HF. Methods and Materials The MEDAMACS screening pilot was a multicenter, prospective, observational study of pts with advanced systolic HF, including 116 pts who underwent right heart catheterization (RHC) within 6 months of enrollment. Three strata were defined: 1. Matched high (MH, RA≥11mmHg +PCWP≥20mmHg) 2. Matched low (ML, RA≤10 mmHg+PCWP≤19mmHg) or 3. Mismatched (MM i.e. RA≤10 mmHg+PCWP≥20mmHg). Pts were assessed for outcomes of death, initiation of inotropes, mechanical circulatory support, or transplant. Results Of the 116 pts in this analysis, 25%, 47%, and 28% pts were in the ML, MH and MM groups respectively. 49 events were recorded by 6 months. The majority of pts with in the MM group had low RA pressure and high PCWP. There were no differences between the 3 groups in baseline demographics, HF etiology, EF, or NYHA class. The MH and MM groups included fewer pts tolerating ACE-inhibitors (ML 76%, MH 50%, MM 58%, p=0.07), and mean Cr was higher in the MM group (ML 1.3 mmol/L, MH 1.6mmol/L, MM 1.8mmol/L, p= 0.02). Six-month event free survival was 75%, 67% and 55% for the ML, MH and MM groups respectively (p=0.249). Conclusions Discordant filling pressures were found in 28% of advanced HF patients on medical therapy and were associated with impaired renal function and lower tolerance of neurohormonal antagonists. Despite limited evidence of congestion by JVP assessment, event rates are high for pts with discordant filling pressures, affirming a role for selective use of invasive hemodynamic assessment in this population.

Background— Apelin is among the most potent stimulators of cardiac contractility known. However, no physiological or pathological role for apelin–angiotensin receptor-like 1 (APJ) signaling has ever been described. Methods and Results— We performed transcriptional profiling using a spotted cDNA microarray with 12 814 unique clones on paired samples of left ventricle obtained before and after placement of a left ventricular assist device in 11 patients. The significance analysis of microarrays and a novel rank consistency score designed to exploit the paired structure of the data confirmed that natriuretic peptides were among the most significantly downregulated genes after offloading. The most significantly upregulated gene was the G-protein–coupled receptor APJ, the specific receptor for apelin. We demonstrate here using immunoassay and immunohistochemical techniques that apelin is localized primarily in the endothelium of the coronary arteries and is found at a higher concentration in cardiac tissue after mechanical offloading. These findings imply an important paracrine signaling pathway in the heart. We additionally extend the clinical significance of this work by reporting for the first time circulating human apelin levels and demonstrating increases in the plasma level of apelin in patients with left ventricular dysfunction. Conclusions— The apelin-APJ signaling pathway emerges as an important novel mediator of cardiovascular control.

Nocardia transvalensis is a rarely reported cause of clinically significant disease, and, to our knowledge, has not been reported previously as a cause of infection in the cardiac transplant population. We report a case of N transvalensis new taxon-2 pulmonary infection that disseminated to the brain and skin in a cardiac transplant recipient despite adequate sulfonamide serum levels. Subsequent isolates were resistant to sulfonamides, and molecular ribotyping of the primary and subsequent isolates confirmed that these were the same N transvalensis new taxon-2 strain. The taxonomic and diagnostic considerations, as well as the clinical significance of anti-microbial-resistant nocardia, are reviewed and discussed herein.

The earliest form of vascular remodeling occurs during embryonic development, during vascular formation. In this process endothelial cells arise and form a dense plexus throughout the mesoderm. This plexus then remodels to form a recognizable branching vascular pattern. This remodeling has been considered to be primarily an endothelial cell event. It is now increasingly clear that this earliest form of remodeling actually represents a complex coordinated development process involving endothelial cells and smooth muscle cells. Recent gene-targeting experiments have begun to dissect the signaling pathways that mediate various aspects of this complex process, which appears to be regulated by secreted factors and physical forces. Subsequently, there is extensive remodeling as the primitive vascular pattern reorganizes to reflect the definitive circulation found in higher vertebrates. And finally, there is continuous remodeling in embryogenesis and during postnatal development as the organism increases in size.

Hematopoietic stem cells (HSCs) reside predominantly in bone marrow, but low numbers of HSCs are also found in peripheral blood. We examined the fate of blood-borne HSCs using genetically marked parabiotic mice, which are surgically conjoined and share a common circulation. Parabionts rapidly established stable, functional cross engraftment of partner-derived HSCs and maintained partner-derived hematopoiesis after surgical separation. Determination of the residence time of injected blood-borne progenitor cells suggests that circulating HSCs/progenitors are cleared quickly from the blood. These data demonstrate that HSCs rapidly and constitutively migrate through the blood and play a physiological role in, at least, the functional reengraftment of unconditioned bone marrow.

Endothelium critically regulates systemic and pulmonary vascular function, playing a central role in hemostasis, inflammation, vasoregulation, angiogenesis, and vascular growth. Indeed, the endothelium integrates signals originating in the circulation with those in the vessel wall to coordinate vascular function. This highly metabolic role differs significantly from the historic view of endothelium, in which it was considered to be merely an inert barrier. New lines of evidence may further change our understanding of endothelium, in regard to both its origin and function. Embryological studies suggest that the endothelium arises from different sites, including angiogenesis of endothelium from macrovascular segments and vasculogenesis of endothelium from microcirculatory segments. These findings suggest an inherent phenotypic distinction between endothelial populations based on their developmental origin. Similarly, diverse environmental cues influence endothelial cell phenotype, critical to not only normal function but also the function of a diseased vessel. Consequently, an improved understanding of site-specific endothelial cell function is essential, particularly with consideration to environmental stimuli present both in the healthy vessel and in development of vasculopathic disease states. The need to examine endothelial cell phenotypes in the context of vascular function served as the basis for a recent workshop sponsored by the National Heart, Lung, and Blood Institute (NHLBI). This report is a synopsis of pertinent topics that were discussed, and future goals and research opportunities identified by the participants of the workshop are presented.

We provide anatomic and functional evidence that nicotine induces angiogenesis. We also show that nicotine accelerates the growth of tumor and atheroma in association with increased neovascularization. Nicotine increased endothelial-cell growth and tube formation in vitro, and accelerated fibrovascular growth in vivo. In a mouse model of hind-limb ischemia, nicotine increased capillary and collateral growth, and enhanced tissue perfusion. In mouse models of lung cancer and atherosclerosis, we found that nicotine enhanced lesion growth in association with an increase in lesion vascularity. These effects of nicotine were mediated through nicotinic acetylcholine receptors at nicotine concentrations that are pathophysiologically relevant. The endothelial production of nitric oxide, prostacyclin and vascular endothelial growth factor might have a role in these effects.

Purpose INTERMACS profiles provide important prognostic information for patients with advanced heart failure (HF) receiving mechanical support. The role for INTERMACS profiling of advanced HF patients undergoing an initial strategy of medical management is not yet known. Methods and Materials The MedaMACS Screening Pilot enrolled 167 pts with chronic NYHA Class III-IV HF, EF≤30%, and ≥1 HF hospitalization in the prior year. Pts were excluded if listed for transplant or on inotropes. Comprehensive data were collected from usual care, with INTERMACS profiles assigned at enrollment using standard definitions. Subjects were followed for 12mos, or until death, VAD or transplant. Event rates were calculated by the Kaplan-Meier method and risk of death or VAD was analyzed using Cox modeling. Results Mean age was 57yrs, EF 17%, 47% had an ischemic etiology, and 57% had HF >5yrs. At enrollment 23% of subjects were INTERMACS profile 4, 32% profile 5, and 45% profile 6/7. Cumulative follow-up was 117 patient-yrs. Patients in lower INTERMACS profiles had been hospitalized more often in the prior 6 mos, were less often on a beta-blocker, and had higher Seattle HF model scores. Lower INTERMACS profile was associated with increased risk of death or VAD by 12 months. [ figure 1 ] Successively lower INTERMACS profile remained strongly associated with failure of medical therapy (HR 1.61, 95%CI 1.12-2.39) after adjustment for renal function, right ventricular function, and Seattle HF score quartile. Conclusions INTERMACS profiles are a useful short-hand for risk stratification in advanced HF. Lower profiles identify patients who may benefit from current mechanical support devices under existing indications.

Introduction Hypersensitivity myocarditis (HM) is a potentially fatal disease that can lead to refractory heart failure if left untreated. Numerous drugs have been implicated in causing HM. We present a case of HM in a heart transplant recipient treated with Rituximab for post-transplant lymphoproliferative disorder (PTLD). Case Report A 59 yo man was diagnosed with PTLD 8 months after undergoing heart transplantation. He had an early 2R acute cellular rejection that resolved with increasing baseline immunosuppression that consisted of tacrolimus, Cellcept and prednisone. An upper endoscopy done for dysphagia, anorexia and weight loss revealed a gastric ulcer and pathology consistent with high grade B cell lymphoma. PET/CT showed cervical, mediastinal, abdominal and pelvic lymphadenopathy as well as hypermetabolic liver and spine lesions consistent with stage IV metastatic disease. Bone marrow biopsy did not show any lymphoma. He was treated with 4 doses of weekly Rituximab and decreased baseline immunosuppression. He was maintained on tacrolimus with a target level around 6 ng/ml and low dose prednisone. He presented one month later with severe heart failure and allograft dysfunction. Heart biopsy showed pericellular and perivascular mixed inflammatory cell infiltrate rich in eosinophils with many degranulating forms suggestive of hypersensitivity myocarditis. There was no evidence of fungal or parasitic infection or heart involvement of the recently diagnosed B cell lymphoma. No eosinophils were seen during the prior cellular rejection. Patient was treated with high dose IV Solu-Medrol and a follow up biopsy one week later showed marked clearing of the eosinophilic infiltrate. Summary This patient presented with allograft dysfunction after receiving Rituximab, an agent putatively associated with hypersensitivity pneumonitis. Although a complete histologic distinction between HM and acute cellular rejection is not feasible, the features of this infiltrate were more consistent with HM, which was attributed to Rituximab.

enrolled NYHA class III/IV HF patients who were not listed for transplant, were not requiring inotropes, had an LVEF 30% and either had 2 HF hospitalizations in 12 mos or 1 HF hospitalization and 1 high-risk clinical feature. Results: Mean age was 57 yrs and LVEF was 17%. The distribution of IM profiles 4, 5, 6 and 7 was 23%, 31%, 34% and 12%, respectively. A majority described limitations with 4 of 5 health state dimensions: mobility (75%), usual activities (80%), pain/discomfort (62%), and anxiety/depression (64%). The mean visual analogue scale (VAS) score was 52 21, which was in-line with previously reported trends (Figure). The mean EQ-5D index score was 0.67 0.19. The EQ-5D index score significantly increased across increasing IM profiles (p 0.01). Diabetes, lower IM profiles, and unemployment status were independently associated with a lower EQ-5D index score (p 0.01) after adjusting for traditional covariates (age 60, male, white, ischemic, and creatinine 1.6) and other covariates that were significant on univariate analysis. Conclusions: Patients with INTERMACS profile 4-7 heart failure have significantly reduced QOL. Lower INTERMACS profiles, diabetes, and unemployment status were independently associated with a worse health state as determined by the EQ-5D index score. This data may be helpful when determining whether LVADs can be beneficial earlier in the spectrum of advanced heart failure.

Introduction: Recent findings report the potential for bone marrow(BM) or cardiac-derived stem and progenitor cell mobilization and differentiation to repair the infarcted myocardium. Following myocardial infarction (MI), there is an influx of inflammatory cells and secretion of cytokines, leading to cardiomyocyte death and ventricular remodeling. Mobilized c-Kitþ progenitor cells, either from the BM or cardiac niches, play a key role in maintenance of the number of myocytes in aging or postMI. We focused on determining the role of the c-Kit receptor in long term remodeling post-MI. Methods and Results: Functional repair in c-kit mutant (W/W) and littermate wild type (WT) mice post-MI was compared by evaluating in vivo left ventricular (LV) pressure-volume performance and pathology at 5 and 24 weeks post-MI. Evaluation of LV end-systolic and diastolic volume (ESV and EDV) showed a significant worsening of heart function and greater left ventricular dilatation at 5 and 24 weeks post-MI in W/W mice compared to WT (Figure 1). Similarly, the W/W sham and MI operated groups developed greater LV dilatation at 24 weeks when compared to W/W sham and MI mice at 5 weeks. Interestingly, WT sham and MI mice did not demonstrate any significant worsening of heart function at 24 weeks when compared to 5 weeks post-MI. Conclusion: This demonstrates the importance of c-Kit receptors in maintaining heart function post-MI and in aging. These findings provide further evidence indicating the presence of BMor cardiac residentderived stem progenitor cells in maintenance of myocardial health with age and post-injury. 133