ERBB signaling attenuates proinflammatory activation of nonclassical monocytes.

Immune activation in chronic systolic heart failure (HF) correlates with disease severity and prognosis. Recombinant neuregulin-1 (rNRG-1) is being developed as a possible therapy for HF, based on the activation of ERBB receptors in cardiac cells. Work in animal models of HF led us to hypothesize that there may be direct effects of NRG-1 on immune system activation and inflammation. We investigated the expression of ERBB receptors and the effect of rNRG-1 isoform glial growth factor 2 (GGF2) in subpopulations of peripheral blood mononuclear cells (PB MNCs) in subjects with HF. We found that human monocytes express both ERBB2 and ERBB3 receptors, with high interindividual variability among subjects. Monocyte surface ERBB3 and TNF-α mRNA expression were inversely correlated in subjects with HF but not in human subjects without HF. GGF2 activation of ERBB signaling ex vivo inhibited LPS-induced TNF-α production, specifically in the CD14lowCD16+ population of monocytes in a phosphoinositide 3-kinase-dependent manner. GGF2 suppression of TNF-α correlated directly with the expression of ERBB3. In vivo, a single dose of intravenous GGF2 reduced TNF-α expression in PB MNCs of HF subjects participating in a phase I safety study of GGF2. These results support a role for ERBB3 signaling in the regulation of TNF-α production from CD14lowCD16+ monocytes and a need for further investigation into the clinical significance of NRG-1/ERBB signaling as a modulator of immune system function.NEW & NOTEWORTHY This study identified a novel role of neuregulin-1 (NRG-1)/ERBB signaling in the control of proinflammatory activation of monocytes. These results further improve our fundamental understanding of cardioprotective effects of NRG-1 in patients with heart failure.

Cardio-Oncology Training: A Proposal From the International Cardioncology Society and Canadian Cardiac Oncology Network for a New Multidisciplinary Specialty.

There is an increasing awareness and clinical interest in cardiac safety during cancer therapy as well as in optimally addressing cardiac issues in cancer survivors. Although there is an emerging expertise in this area, known as cardio-oncology, there is a lack of organization in the essential components of contemporary training. This proposal, an international consensus statement organized by the International Cardioncology Society and the Canadian Cardiac Oncology Network, attempts to marshal the important ongoing efforts for training the next generation of cardio-oncologists. The necessary elements are outlined, including the expectations for exposure necessary to develop adequate training. There should also be a commitment to local, regional, and international education and research in cardio-oncology as a requirement for advancement in the field.

A Phase I, Single Ascending Dose Study of Cimaglermin Alfa (Neuregulin 1ß3) in Patients With Systolic Dysfunction and Heart Failure.

A first-in-human, phase 1, double blind, placebo-controlled, single ascending dose study examined the safety, tolerability, and exploratory efficacy of intravenous infusion of a recombinant growth factor, cimaglermin alfa, in patients with heart failure and left ventricular systolic dysfunction (LVSD). In these patients on optimal guideline-directed medical therapy, cimaglermin treatment was generally tolerated except for transient nausea and headache and a dose-limiting toxicity was noted at the highest planned dose. There was a dose-dependent improvement in left ventricular ejection fraction lasting 90 days following infusion. Thus, cimaglermin is a potential therapy to enhance cardiac function in LVSD and warrants further investigation.

Neuregulin-1 signaling in the pathogenesis of chemotherapy-induced heart failure.

The National Cancer Institute estimates that approximately 13.7 million Americans with a history of cancer were alive on January 1, 2012. With the rising number of cancer survivors, there is an increased focus on how chemotherapy agents modulate the cardiovascular biology and cause chemotherapy-related heart failure in certain patients. Neuregulin-1 (NRG-1) is an important cardiac growth factor that is essential for normal myocardial development and maintenance. Certain chemotherapy agents perturb the normal NRG-1 signaling in the cardiovascular system and cause cardiac dysfunction and, in some cases, symptomatic heart failure. As researchers have learned the critical importance of NRG-1 within the cardiovascular system, more attention has been focused on the potential use of NRG-1 as biomarker and therapy for the treatment of heart failure. This review will highlight the biology of NRG-1 within the cardiovascular system, its role in chemotherapy-induced heart failure, and the translational potential of NRG-1 as treatment for heart failure.