Cardiotoxicity in childhood cancer survivors: strategies for prevention and management

Rationale and design of the Children's Oncology Group study AAML1831 integrated cardiac substudies in pediatric acute myeloid leukemia therapy

Background

Pediatric acute myeloid leukemia (AML) therapy is associated with substantial short- and long-term treatment-related cardiotoxicity mainly due to high-dose anthracycline exposure. Early left ventricular systolic dysfunction (LVSD) compromises anthracycline delivery and is associated with inferior event-free and overall survival in de novo pediatric AML. Thus, effective cardioprotective strategies and cardiotoxicity risk predictors are critical to optimize cancer therapy delivery and enable early interventions to prevent progressive LVSD. While dexrazoxane-based cardioprotection reduces short-term cardiotoxicity without compromising cancer survival, liposomal anthracycline formulations have the potential to mitigate cardiotoxicity while improving antitumor efficacy. This overview summarizes the rationale and methodology of cardiac substudies within AAML1831, a randomized Children's Oncology Group Phase 3 study of CPX-351, a liposomal formulation of daunorubicin and cytarabine, in comparison with standard daunorubicin/cytarabine with dexrazoxane in the treatment of de novo pediatric AML.

Methods/design

Children (age <22 years) with newly diagnosed AML were enrolled and randomized to CPX-351-containing induction 1 and 2 (Arm A) or standard daunorubicin and dexrazoxane-containing induction (Arm B). Embedded cardiac correlative studies aim to compare the efficacy of this liposomal anthracycline formulation to dexrazoxane for primary prevention of cardiotoxicity by detailed core lab analysis of standardized echocardiograms and serial cardiac biomarkers throughout AML therapy and in follow-up. In addition, AAML1831 will assess the ability of early changes in sensitive echo indices (e.g., global longitudinal strain) and cardiac biomarkers (e.g., troponin and natriuretic peptides) to predict subsequent LVSD. Finally, AAML1831 establishes expert consensus-based strategies in cardiac monitoring and anthracycline dose modification to balance the potentially competing priorities of cardiotoxicity reduction with optimal leukemia therapy.

Discussion

This study will inform diagnostic, prognostic, preventative, and treatment strategies regarding cardiotoxicity during pediatric AML therapy. Together, these measures have the potential to improve leukemia-free and overall survival and long-term cardiovascular health in children with AML. Clinical trial registration: https://clinicaltrials.gov/, identifier NCT04293562.

Pharmacotherapy for Cancer Treatment-Related Cardiac Dysfunction and Heart Failure in Childhood Cancer Survivors

The number of childhood cancer survivors is increasing rapidly. According to American Association for Cancer Research, there are more than 750,000 childhood cancer survivors in the United States and Europe. As the number of childhood cancer survivors increases, so does cancer treatment-related cardiac dysfunction (CTRCD), leading to heart failure (HF). It has been reported that childhood cancer survivors who received anthracyclines are 15 times more likely to have late cancer treatment-related HF and have a 5-fold higher risk of death from cardiovascular (CV) disease than the general population. CV disease is the leading cause of death in childhood cancer survivors. The increasing need to manage cancer survivor patients has led to the rapid creation and adaptation of cardio-oncology. Cardio-oncology is a multidisciplinary science that monitors, treats, and prevents CTRCD. Many guidelines and position statements have been published to help diagnose and manage CTRCD, including those from the American Society of Clinical Oncology, the European Society of Cardiology, the Canadian Cardiovascular Society, the European Society of Medical Oncology, the International Late Effects of Childhood Cancer Guideline Harmonization Group, and many others. However, there remains a gap in identifying high-risk patients likely to develop cardiomyopathy and HF in later life, thus reducing primary and secondary measures being instituted, and when to start treatment when there is echocardiographic evidence of left ventricular (LV) dysfunctions without symptoms of HF. There are no randomized controlled clinical trials for treatment for CTRCD leading to HF in childhood cancer survivors. The treatment of HF due to cancer treatment is similar to the guidelines for general HF. This review describes the latest pharmacologic therapy for preventing and treating LV dysfunction and HF in childhood cancer survivors based on expert consensus guidelines and extrapolating data from adult HF trials.

Analyzing Cardiovascular Characteristics of Patients Initially Diagnosed with Breast Cancer in Saudi Arabia

Introduction Cancer is a condition where abnormal cells proliferate uncontrollably, leading to metastasis, which can be related to death. Breast cancer is the most prevalent type among women worldwide. Early detection with screening mammography has contributed to the decline in breast cancer incidence and mortality. Breast cancer patients are more likely to develop cardiovascular disease, with elderly patients dying from complications. Understanding the patients' cardiovascular status prior to treatment is essential. The study's objective was to evaluate the cardiovascular characteristics of women with breast cancer at diagnosis within the designated time frame of one year. Methodology This was a retrospective study that focused on patients in Taif City, Saudi Arabia, who were initially diagnosed with primary breast cancer over a span of one year. The inclusion criteria encompassed eligible patients, while those not meeting the criteria were excluded. Data extraction from patients' records was conducted, and the analysis was executed using IBM SPSS Statistics for Windows, Version 26.0 (Released 2019; IBM Corp., Armonk, New York, United States). Results This study analyzed the cardiovascular attributes of breast cancer patients, focusing on 136 female cases. The study found significant patterns concerning cardiovascular risk factors in breast cancer patients, categorized by menopausal status. Premenopausal female cases had a mean age of 43.09 ± 8.31 years, while postmenopausal patients had an average age of 58.07 ± 11.70 years. Postmenopausal patients had a higher prevalence of overweight/obesity, irregular menstrual cycles, type II diabetes, hypertension, and hyperlipidemia compared to their premenopausal counterparts. No significant differences were found between the two groups regarding low-density lipoprotein (LDL) cholesterol levels, axillary lymph node metastasis, or distant metastasis. This study emphasized the importance of regular check-ups for menopausal women to detect potential health complications early. Conclusion In summary, breast cancer is a global health concern, and understanding its impact on the cardiovascular system is crucial for comprehensive patient care. A study in Saudi Arabia found associations between cardiovascular risk factors and menopausal status in breast cancer patients. Postmenopausal patients had more prevalent risk factors, emphasizing the need for proactive assessment and management. Age-appropriate screenings and interventions are essential. Integrated healthcare approaches should consider the interplay between breast cancer and cardiovascular health, with medical professionals vigilant in evaluating and addressing risk factors to mitigate complications and optimize long-term outcomes.

In Vitro Evaluation of Ferutinin Rich-Ferula communis L., ssp. glauca, Root Extract on Doxorubicin-Induced Cardiotoxicity: Antioxidant Properties and Cell Cycle Modulation

The clinical use of anthracycline Doxorubicin as an antineoplastic drug in cancer therapy is limited by cardiotoxic effects that can lead to congestive heart failure. Recent studies have shown several promising activities of different species of the genus Ferula belonging to the Apiaceae Family. Ferula communis is the main source of Ferutinin-a bioactive compound isolated from many species of Ferula-studied both in vitro and in vivo because of their different effects, such as estrogenic, antioxidant, anti-inflammatory, and also antiproliferative and cytotoxic activity, performed in a dose-dependent and cell-dependent way. However, the potential protective role of Ferutinin in myocardium impairment, caused by chemotherapeutic drugs, still represents an unexplored field. The aim of this study was to test the effects of Ferutinin rich-Ferula communis L. root extract (FcFE) at different concentrations on H9C2 cells. Moreover, we evaluated its antioxidant properties in cardiomyocytes in order to explore new potential therapeutic activities never examined before in other experimental works. FcFE, at a concentration of 0.25 µM, in the H9C2 line, significantly reduced the ROS production induced by H2O2 (50 µM and 250 µM) and traced the cell mortality of the H9C2 co-treated with Ferutinin 0.25 µM and Doxorubicin (0.5 µM and 1 µM) to control levels. These results showed that FcFE could protect against Doxorubicin-induced cardiotoxicity. Further molecular characterization of this natural compound may open the way for testing FcFE at low concentrations in vivo and in clinical studies as an adjuvant in cancer therapy in association with anthracyclines to prevent side effects on heart cells.

Cardiotoxicity in children with cancer treated with anthracyclines: A position statement on dexrazoxane

Cardiovascular disease is the leading cause of non-malignant morbidity and mortality in childhood cancer survivors (CCSs). Anthracyclines are included in many treatment regimens for paediatric cancer, but unfortunately, these compounds are cardiotoxic. One in 10 CCSs who has received an anthracycline will develop a symptomatic cardiac event over time. Given the crucial need to mitigate anthracycline-related cardiotoxicity (ARC), the authors critically examined published data to identify effective cardioprotective strategies. Based on their expert analysis of contemporary literature data, it was concluded that consideration should be given for routine use of dexrazoxane in children with cancer who are at risk of ARC.

Abnormal HDL lipid and protein composition following pediatric cancer treatment: an associative study

BACKGROUND

Long-term childhood cancer survivors (CCS) are at high risk of having dyslipidemia including low high density lipoprotein cholesterol (HDL-C). However, little is known about the prevalence of low HDL-C and the impact of therapy exposure on HDL composition early after treatment is terminated.

METHODS

This associative study included 50 children and adolescents who had completed their cancer treatments (< 4 years). Clinical characteristics (demographic, diagnosis, treatment, anthropometric parameters), fasting plasma lipids, apoliporoteins (Apo) A-I and composition of HDL fractions (HDL2 and HDL3) were assessed. Data were stratified according to the presence of dyslipidemia and median doses of therapeutic agents and compared using Fisher exact or Mann-Whitney tests. Univariate binary logistic regression analyses were carried out to evaluate the associations between the clinical and biochemical characteristics and having low HDL-C. Composition of HDL2 and HDL3 particles was assessed in a sub-group of 15 patients and compared to 15 age- and sex-matched healthy controls using Wilcoxon paired test.

RESULTS

Of the 50 pediatric cancer patients included in this study (mean age: 11.30 ± 0.72 y; mean time since end of treatment: 1.47 ± 0.12 y; male: 38%), 8 had low HDL-C (16%), all of which were adolescent at diagnosis. Higher doses of doxorubicin were associated with lower HDL-C and Apo A-I levels. In hypertriglyceridemic patients and compared to normolipidemics, triglycerides (TG) content was greater in HDL2 and HDL3 fractions whereas esterified cholesterol (EC) content was lower in HDL2. Enrich TG content of HDL3 and lower EC of HDL2 was found in patients exposed to ≥ 90 mg/m² doxorubicin. Factors positively associated with the risk of having low HDL-C were age, being overweight or obese and exposure to doxorubicin ≥ 90 mg/m². Compared to healthy controls, a sub-group of 15 patients showed higher TG and free cholesterol (FC) content of HDL2 and HDL3 and lower EC content in HDL3.

CONCLUSIONS

Overall, we found abnormalities in HDL-C and Apo A-I levels and in HDL composition early after pediatric cancer treatment that are influenced by age, overweight or obesity status and exposure to doxorubicin.

Dexrazoxane Treatments Limits Subclinical Cardiac Dysfunction in Childhood Acute Lymphoblastic Leukemia Survivors Exposed to Doxorubicin Treatments

INTRODUCTION

Doxorubicin leads to dose dependent cardiotoxicity in childhood acute lymphoblastic leukemia (ALL) survivors. We investigated survivors' heart health using echocardiography and evaluated doxorubicin and dexrazoxane treatments on cardiac function.

METHODS

A total of 196 childhood ALL survivors were stratified (standard risk [SR], high risk with and without dexrazoxane (HR+DEX and HR). We performed a complete transthoracic echocardiographic assessment with M-mode echocardiography, Doppler, and Tissue Doppler. We used 2-dimensional and 3-dimensional echocardiography to measure the left ventricular ejection fraction, whereas myocardial strain imaging was used to obtain global strain indices.

RESULTS

Although most cardiac and arterial dimension parameters were not different between groups, a difference was observed in posterior intima of the right carotid ( P =0.017). Diastolic functions analyses reported that LV shortening fraction and left and right ventricular lateral S' wave amplitudes were lower in HR than in SR and HR+DEX groups ( P =0.028, P =0.048, and P =0.005, respectively). The LV lateral E' in diastolic function was lower in the HR than in SR and HR+DEX groups ( P =0.036). The LV end-systolic wall stress was higher in HR than in SR and HR+DEX groups ( P =0.009). A decrease contractility was observed, while the effect was not group specific. Strain rate was not different between groups, as opposed to tissue Doppler measurements.

CONCLUSIONS

This study showed that dexrazoxane treatments could limit subclinical cardiac dysfunction in childhood ALL survivors, whereas survivors in HR group who did not receive dexrazoxane had potential subclinical cardiac damage observable in heart failure patients. Echocardiographic screening for survivors must be part of the follow-up routine in cardio-oncology.

Cell death regulation in myocardial toxicity induced by antineoplastic drugs

Homeostatic regulation of cardiomyocytes plays a critical role in maintaining normal physiological activity of cardiac tissue. Severe cardiotoxicity can lead to heart disease, including but not limited to arrhythmias, myocardial infarction and cardiac hypertrophy. In recent years, significant progress has been made in developing new therapies for cancer that have dramatically changed the treatment of several malignancies and continue to improve patient survival, but can also lead to serious cardiac adverse effects. Mitochondria are key organelles that maintain homeostasis in myocardial tissue and have been extensively involved in various cardiovascular disease episodes, including ischemic cardiomyopathy, heart failure and stroke. Several studies support that mitochondrial targeting is a major determinant of the cardiotoxic effects triggered by chemotherapeutic agents increasingly used in solid and hematologic tumors. This antineoplastic therapy-induced mitochondrial toxicity is due to different mechanisms, usually altering the mitochondrial respiratory chain, energy production and mitochondrial kinetics, or inducing mitochondrial oxidative/nitrosative stress, ultimately leading to cell death. This review focuses on recent advances in forms of cardiac cell death and related mechanisms of antineoplastic drug-induced cardiotoxicity, including autophagy, ferroptosis, apoptosis, pyroptosis, and necroptosis, explores and evaluates key proteins involved in cardiac cell death signaling, and presents recent advances in cardioprotective strategies for this disease. It aims to provide theoretical basis and targets for the prevention and treatment of pharmacological cardiotoxicity in clinical settings.

Selective Intra-Arterial Doxorubicin Eluting Microsphere Embolization for Desmoid Fibromatosis: A Combined Prospective and Retrospective Study

Simple Summary

Desmoid fibromatoses (DFs) are locally aggressive tumors composed of monoclonal fibroblasts within an abundant extracellular matrix. Systemic treatment with doxorubicin is effective, but associated with significant toxicity. We investigated arterial doxorubicin eluting embolization (DEE), an approach that delivers high doxorubicin concentrations to the tumor with limited systemic drug exposure, in 24 patients (median age, 24 years; interquartile range, 16–34). Most patients (71%) had one or more than one prior DFs treatment (surgery, systemic therapy, or both). Patients underwent a median of two (range, 1–4) DEE treatments, with a median of 49 mg (range, 8–75) doxorubicin per treatment. Efficacy outcomes were available for 23 patients. With a median follow-up of 8 months (interquartile range, 3–13), median tumor volumes decreased by 59% (interquartile range, 40–71%). Of 23 patients, 9 (39%), 12 (52%), and 2 (9%) had a partial response, stable disease, and progressive disease, respectively. The procedure was safe and well tolerated.

Abstract

Desmoid fibromatoses (DFs) are locally aggressive tumors composed of monoclonal fibroblasts within an abundant extracellular matrix. Systemic doxorubicin treatment is effective, but toxic. We investigated arterial doxorubicin eluting embolization (DEE), an approach characterized by high drug concentrations in the tumor alongside limited systemic drug exposure. The primary and secondary endpoints were radiological response using MRI and RECIST 1.1, respectively. The study included 24 patients (median age, 24; interquartile range, 16–34 years). Data were collected prospectively for 9 patients and retrospectively for 15 patients. The most frequent tumor locations were chest/abdomen wall and neck/shoulder/axilla (29% each). Of 24 patients, 7 (24%) were treatment naïve, and 17 (71%) had received one or two prior treatments. Patients underwent a median of two treatments (range, 1–4), with a median of 49 mg (range, 8–75) doxorubicin/treatment. Efficacy outcomes were available for 23 patients. With a median follow-up of 8 months (interquartile range, 3–13), median tumor volumes decreased by 59% (interquartile range, 40–71%) and T2 signal intensity decreased by 36% (interquartile range, 19–55%). Of 23 patients, 9 (39%), 12 (52%), and 2 (9%) had a partial response, stable disease, and progressive disease, respectively. DEE was safe and well tolerated, with one reported grade 3–4 adverse event (cord injury). In conclusion, DEE was safe and achieved rapid clinical/volumetric responses in DFs.

Doxorubicin-induced cardiotoxicity is mediated by neutrophils through release of neutrophil elastase

The mechanisms by which Doxorubicin (Dox) causes acute and late cardiotoxicity are not completely understood. One understudied area is the innate immune response, and in particular the role of neutrophils in Dox-induced cardiotoxicity. Here, using echocardiography, flow cytometry and immunofluorescence staining, we demonstrated increased infiltration of neutrophils that correlated with decreased heart function, disruption of vascular structures and increased collagen deposition in the heart after Dox treatment. Depleting neutrophils protected the heart from Dox-induced cardiotoxicity and changes in vascular structure. Furthermore, our data using neutrophil elastase (NE) knock-out mice and the NE inhibitor AZD9668 suggest that neutrophils cause this damage by releasing NE and that inhibiting NE can prevent Dox-induced cardiotoxicity. This work shows the role of neutrophils and NE in Doxorubicin-induced cardiotoxicity for the first time and suggests a new possible therapeutic intervention.

Cardio-Oncology Drug Interactions: A Scientific Statement From the American Heart Association

In the cardio-oncology population, drug interactions are of particular importance given the complex pharmacological profile, narrow therapeutic index, and inherent risk of therapies used to manage cardiovascular disease and cancer. Drug interactions may be beneficial or detrimental to the desired therapeutic effect. Clinicians in both cardiology and oncology should be cognizant of these potential drug-drug interactions that may reduce the efficacy or safety of either cardiovascular or cancer therapies. These risks can be mitigated through increased recognition of potential drug-drug interaction, use of alternative medications when possible, and careful monitoring. This scientific statement provides clinicians with an overview of pharmacodynamic and pharmacokinetic drug-drug interactions in patients with cancer exposed to common cardiovascular and cancer medications.

The sGC-cGMP Signaling Pathway as a Potential Therapeutic Target in Doxorubicin-Induced Heart Failure: A Narrative Review

The anti-cancer agent doxorubicin (DOX) has high cardiotoxicity that is linked to DOX-mediated increase in oxidative stress, mitochondrial iron overload, DNA damage, autophagy, necrosis, and apoptosis, all of which are also associated with secondary tumorigenicity. This limits the clinical application of DOX therapies. Previous studies have attributed DOX-mediated cardiotoxicity to mitochondrial iron accumulation and the production of reactive oxygen species (ROS), which seem to be independent of its anti-tumor DNA damaging effects. Chemo-sensitization of soluble guanylate cyclase (sGC) in the cyclic guanosine monophosphate (cGMP) pathway induces tumor cell death despite the cardiotoxicity associated with DOX treatment. However, sGC-cGMP signaling must be activated during heart failure to facilitate myocardial cell survival. The sGC pathway is dependent on nitric oxide and signal transduction via the nitric oxide-sGC-cGMP pathway and is attenuated in various cardiovascular diseases. Additionally, cGMP signaling is regulated by the action of certain phosphodiesterases (PDEs) that protect the heart by inhibiting PDE, an enzyme that hydrolyses cGMP to GMP activity. In this review, we discuss the studies describing the interactions between cGMP regulation and DOX-mediated cardiotoxicity and their application in improving DOX therapeutic outcomes. The results provide novel avenues for the reduction of DOX-induced secondary tumorigenicity and improve cellular autonomy during DOX-mediated cardiotoxicity.

PET Tracers for Imaging Cardiac Function in Cardio-oncology

PURPOSE OF REVIEW

Successful treatment of cancer can be hampered by the attendant risk of cardiotoxicity, manifesting as cardiomyopathy, left ventricle systolic dysfunction and, in some cases, heart failure. This risk can be mitigated if the injury to the heart is detected before the onset to irreversible cardiac impairment. The gold standard for cardiac imaging in cardio-oncology is echocardiography. Despite improvements in the application of this modality, it is not typically sensitive to sub-clinical or early-stage dysfunction. We identify in this review some emerging tracers for detecting incipient cardiotoxicity by positron emission tomography (PET).

RECENT FINDINGS

Vectors labeled with positron-emitting radionuclides (e.g., carbon-11, fluorine-18, gallium-68) are now available to study cardiac function, metabolism, and tissue repair in preclinical models. Many of these probes are highly sensitive to early damage, thereby potentially addressing the limitations of current imaging approaches, and show promise in preliminary clinical evaluations. The overlapping pathophysiology between cardiotoxicity and heart failure significantly expands the number of imaging tools available to cardio-oncology. This is highlighted by the emergence of radiolabeled probes targeting fibroblast activation protein (FAP) for sensitive detection of dysregulated healing process that underpins adverse cardiac remodeling. The growth of PET scanner technology also creates an opportunity for a renaissance in metabolic imaging in cardio-oncology research.

Mitochondrial-Targeted Therapy for Doxorubicin-Induced Cardiotoxicity

Anthracyclines, such as doxorubicin, are effective chemotherapeutic agents for the treatment of cancer, but their clinical use is associated with severe and potentially life-threatening cardiotoxicity. Despite decades of research, treatment options remain limited. The mitochondria is commonly considered to be the main target of doxorubicin and mitochondrial dysfunction is the hallmark of doxorubicin-induced cardiotoxicity. Here, we review the pathogenic mechanisms of doxorubicin-induced cardiotoxicity and present an update on cardioprotective strategies for this disorder. Specifically, we focus on strategies that can protect the mitochondria and cover different therapeutic modalities encompassing small molecules, post-transcriptional regulators, and mitochondrial transfer. We also discuss the shortcomings of existing models of doxorubicin-induced cardiotoxicity and explore advances in the use of human pluripotent stem cell derived cardiomyocytes as a platform to facilitate the identification of novel treatments against this disorder.

Pharmacogenomics in Children

Historically genetics has not been considered when prescribing drugs for children. However, it is clear that genetics are not only an important determinant of disease in children but also of drug response for many important drugs that are core agents used in the therapy of common problems in children. Advances in therapy and in the ethical construct of children's research have made pharmacogenomic assessment for children much easier to pursue. It is likely that pharmacogenomics will become part of the therapeutic decision-making process for children, notably in areas such as childhood cancer where weighing benefits and risks of therapy is crucial.

Minimizing cardiac toxicity in children with acute myeloid leukemia

Anthracycline chemotherapy remains an integral component of modern pediatric acute myeloid leukemia (AML) regimens and is often delivered at high doses to maximize cancer survival. Unfortunately, high-dose anthracyclines are associated with a significant risk of cardiotoxicity, which may result in early and/or long-term left ventricular systolic dysfunction and heart failure. Moreover, the development of cardiotoxicity during pediatric AML therapy is associated with lower event-free and overall survival, which may be partially attributable to incomplete anthracycline delivery. A combined strategy of primary cardioprotection and close cardiac monitoring can maximize chemotherapy delivery while reducing the toxicity of intensive AML therapy. Primary cardioprotection using dexrazoxane reduces short-term cardiotoxicity without compromising cancer survival. Liposomal anthracycline formulations, which are under active investigation, have the potential to mitigate cardiotoxicity while also improving antitumor efficacy. Primary cardioprotective strategies may reduce but not eliminate the risk of cardiotoxicity; therefore, close cardiac monitoring is also needed. Standard cardiac monitoring consists of serial echocardiographic assessments for left ventricular ejection fraction decline. Global longitudinal strain has prognostic utility in cancer therapy-related cardiotoxicity and may be used as an adjunct assessment. Additional cardioprotective measures should be considered in response to significant cardiotoxicity; these include cardiac remodeling medications to support cardiac recovery and anthracycline dose interruption and/or regimen modifications. However, the withholding of anthracyclines should be limited to avoid compromising cancer survival. A careful approach to cardioprotection during AML therapy is critical to maximize the efficacy of leukemia treatment while minimizing the short- and long-term risks of cardiotoxicity.

Pediatric Chemotherapy Drugs Associated With Cardiotoxicity

Pediatric cancers are a common cause of childhood morbidity. As a result, chemotherapeutic regimens have been designed to target childhood cancers. These medications are necessary to treat pediatric cancers, however, oncology management options are accompanied by multiple negative and potentially fatal adverse effects. Although anthracyclines are the most commonly used chemotherapeutic agents associated with cardiotoxicity, we also explore other chemotherapeutic drugs used in children that can potentially affect the heart. Genetic variations resulting in single nucleotide polymorphism (SNP) have the propensity to modify the cardiotoxic effects of the chemotherapy drugs. The clinical presentation of the cardiac effects can vary from arrhythmias and heart failure to completely asymptomatic. A range of imaging studies and laboratory investigations can protect the heart from severe outcomes. The physiology of the heart and the effect of drugs in children vary vividly from adults; therefore, it is crucial to study the cardiotoxic effect of chemotherapy drugs in the pediatric population. This review highlights the potential contributing factors for cardiotoxicity in the pediatric population and discusses the identification and management options.

Cardiovascular status of breast cancer patients before and after receiving anthracycline chemotherapy regimen

Aim

To explore the effect of TEC chemotherapy regimen (Docetaxel + Epirubicin + Cyclophosphamide) on traditional cardiovascular risk factors, atherosclerotic cardiovascular disease and cardiac electrical activity.

Design

243 patients with first initially diagnosed breast cancer were collected who receiving TEC chemotherapy.

Methods

Univariate analysis, multivariate analysis, binary logistic regression analysis and statistical description were used to analyse the data.

Results

Among the first diagnosed patients, prevalence of hypertension and overweight/obesity in postmenopausal patients were significantly higher than premenopausal group. Compared with initially diagnosed state, incidence of hyperlipidaemia increased significantly after TEC chemotherapy, blood glucose level was remarkably increased, and prevalence of hyperuricaemia was significantly increased, changes of blood pressure level and prevalence rate of hypertension were not significant, and there was no statistical difference. Different menopause status showed the same trend. Atherosclerotic cardiovascular disease risk stratification showed after chemotherapy low‐risk patients decrease, medium‐risk and high‐risk people increased. Grouped by menstrual status, after chemotherapy, both groups showed the same trend. The independent influencing factors of increased heart rate after chemotherapy were postmenopausal status. Postmenopausal patients had more cardiovascular risk factors than premenopausal patients. After receiving chemotherapy, levels of cardiovascular risk factors in both groups mostly changed to the direction of disease. Chemotherapy drugs increase the risk of atherosclerotic cardiovascular disease in breast cancer patients. It is necessary to strengthen interdisciplinary cooperation to dynamic assess the cardiovascular health of patients of breast cancer patients.

Evaluation of Cardiotoxic Effects of Anthracyclines by Tissue Doppler Imaging in Survivors of Childhood Cancer

BACKGROUND

Childhood cancer survivors (CCSs) are at risk for anthracycline-induced cardiotoxicity which tends to be more prominent long after completion of the chemotherapy. The aim of this study was to examine echocardiographic parameters of anthracycline-induced subclinical cardiotoxicity in children who had received chemotherapy.

MATERIALS AND METHODS

A cross-sectional single-center study was conducted in a tertiary level university hospital in Eskisehir, Turkey. A total of 50 CCSs and 40 healthy peers were included. The CCSs were divided into 3 subgroups according to cumulative anthracycline dose (100-200 mg/m2, 201-299 mg/m2, and ≥ 300 mg/m2). Biventricular cardiac examination was performed with conventional echocardiography and tissue Doppler echocardiography imaging (TDI).

RESULTS

The mean duration from termination of chemotherapy to echocardiographic assessment was 3.9 ± 2.2 years. The mean age of the CCSs was 11.6 ± 3.9 years. TDI-derived mitral annular isovolumetric relaxation time (IVRT) and myocardial performance index (MPI) were higher in the high-dose group of CCSs than in controls (P = .006, P = .007, P < .001, P = .0014, respectively). IVRT was also higher in patients with ≥ 300 mg/m2 cumulative dose than in those with < 200 mg/m2 (P = .007). TDI-derived mitral annular MPI and IVRT were significantly associated with cumulative anthracycline dose (r = 0.288, P = .006, r = 0.340, P = .001).

CONCLUSION

A cumulative anthracycline dose > 300 mg/m2 may lead to subclinical cardiotoxicity, and is therefore a potential risk factor for late onset cardiac failure. TDI-derived MPI can be a sensitive tool to reveal subtle signs of myocardial damage, which may facilitate implementation of preventive therapies for patients suspected to be at risk.

Free radical induced activity of an anthracycline analogue and its MnII complex on biological targets through in situ electrochemical generation of semiquinone

Cytotoxicity by anthracycline antibiotics is attributed to several pathways. Important among them are formation of free-radical intermediates. However, their generation makes anthracyclines cardiotoxic which is a concern on their use as anticancer agents. Hence, any change in redox behavior that address cardiotoxicity is welcome. Modulation of redox behavior raises the fear that cytotoxicity could be compromised. Regarding the generation of free radical intermediates on anthracyclines, a lot depends on the surrounding environment (oxic or anoxic), polarity and pH of the medium. In case of anthracyclines, one-electron reduction to semiquinone or two-electron reduction to quinone-dianion are crucial both for cytotoxicity and for cardiotoxic side effects. The disproportion-comproportionation equilibria at play between quinone-dianion, free quinone and semiquinone control biological activity. Whatever is the form of reduction, semiquinones are generated as a consequence of the presence of anthracyclines and these interact with a biological target. Alizarin, a simpler anthracycline analogue and its Mn^II complex were subjected to electrochemical reduction to realize what happens when anthracyclines are reduced by compounds present in cells as members of the electron transport chain. Glassy carbon electrode maintained at the pre-determined reduction potential of a compound was used for reduction of the compounds. Nucleobases and calf thymus DNA that were maintained in immediate vicinity of such radical generation were used as biological targets. Changes due to the generated species under aerated/de-aerated conditions on nucleobases and on DNA helps one to realize the process by which alizarin and its Mn^II complex might affect DNA. The study reveals alizarin was more effective on nucleobases than the complex in the free radical pathway. Difference in damage caused by alizarin and the Mn^II complex on DNA is comparatively less than that observed on nucleobases; the complex makes up for any inefficacy in the free radical pathway by its other attributes.

Cardiovascular characteristics of patients initially diagnosed breast cancer

Objective

We aimed to explore the cardiovascular characteristics of patients who were initially diagnosed with breast cancer.

Methods

A total of 600 patients who were diagnosed with primary breast cancer were included in this retrospective study. The data of fasting blood glucose, total cholesterol, total triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, lipoprotein (a) (LP (a)) and serum uric acid were collected. Univariate analysis was used to evaluate the cardiovascular risk factors (CVRFs) in patients with breast cancer. The arteriosclerotic cardiovascular disease (ASCVD) risk assessment was performed. Multivariate analysis was used to identify the factors that influenced axillary lymph node metastasis (ALNM).

Results

Compared with the premenopausal group, the prevalence of overweight/obesity (47.6% vs. 35.2%), diabetes (12.8% vs. 4.3%) and hypertension (49.7% vs. 26.3%) were significantly increased in the postmenopausal group (p < 0.05). Comparisons of rural patients and urban patients showed that there were significant differences in the diagnostic age (49.94 ± 9.92 vs. 52.59 ± 11.13) in the rural patients was notably younger in comparison with the urban patients (p < 0.05). However, the number of menopausal patients (44.3% vs. 53.3%) in the rural group were decreased in comparison with the urban group (p < 0.05). In ASCVD risk stratification, the proportion of low-risk patients (56.4% vs. 90.8%), medium-risk patients (20.6% vs 0.3%) and high-risk patients (19.3% vs. 6.6%) were significantly different between the postmenopausal group and premenopausal group (p < 0.05). Residence (OR 0.735; 95% CI 0.516–1.046; p = 0.087), the number of children (OR 1.250; 95% CI 0.990–1.578; p = 0.061) and LP (a) of ≥ 500 mg/L (OR 0.603; 95% CI 0.342–1.063; p = 0.080) were independent influencing factors of ALNM.

Conclusion

Postmenopausal patients have more CVRFs and higher risks of ASCVD than premenopausal patients initially diagnosed with breast cancer. There was a correlation between CVRFs and ALNM in patients with breast cancer.

Anti-Metastatic and Anti-Angiogenic Effects of Curcumin Analog DK1 on Human Osteosarcoma Cells In Vitro

Osteosarcoma (OS) is a life-threatening malignant bone tumor associated with poor prognosis among children. The survival rate of the patient is still arguably low even with intensive treatment provided, plus with the inherent side effects from the chemotherapy, which gives more unfavorable outcomes. Hence, the search for potent anti-osteosarcoma agent with promising safety profile is still on going. Natural occurring substance like curcumin has gained a lot of attention due to its splendid safety profile as well as it pharmacological advantages such as anti-metastasis and anti-angiogenesis. However, natural curcumin was widely known for its poor cellular uptake, which undermines all potential that it possesses. This prompted the development of synthetically synthesized curcuminoid analog, known as (Z)-3-hydroxy-1-(2-hydroxyphenyl)-3-phenylprop-2- en-1-one (DK1). In this present study, in vitro scratch assay, transwell migration/invasion assay, HUVEC tube formation assay, and ex vivo rat aortic ring assays were performed in order to investigate the anti-metastatic and anti-angiogenic potential of DK1. For further comprehension of DK1 mechanism on human osteosarcoma cell lines, microarray gene expression analysis, quantitative polymerase chain reaction (qPCR), and proteome profiler were adopted, providing valuable forecast from the expression of important genes and proteins related to metastasis and angiogenesis. Based on the data gathered from the bioassays, DK1 was able to inhibit the metastasis and angiogenesis of human osteosarcoma cell lines by significantly reducing the cell motility, number of migrated and invaded cells as well as the tube formation and micro-vessels sprouting. Additionally, DK1 also has significantly regulated several cancer pathways involved in OS proliferation, metastasis, and angiogenesis such as PI3K/Akt and NF-κB in both U-2 OS and MG-63. Regulation of PI3K/Akt caused up-regulation of genes related to metastasis inhibition, namely, PTEN, FOXO, PLK3, and GADD45A. Meanwhile, NF-κB pathway was regulated by mitigating the expression of NF-κB activator such as IKBKB and IKBKE in MG-63, whilst up-regulating the expression of NF-κB inhibitors such as NFKBIA and NFKBIE in U-2 OS. Finally, DK1 also has successfully hindered the metastatic and angiogenic capability of OS cell lines by down-regulating the expression of pro-metastatic genes and proteins like MMP3, COL11A1, FGF1, Endoglin, uPA, and IGFBP2 in U-2 OS. Whilst for MG-63, the significantly down-regulated oncogenes were Serpin E1, AKT2, VEGF, uPA, PD-ECGF, and Endoglin. These results suggest that curcumin analog DK1 may serve as a potential new anti-osteosarcoma agent due to its anti-metastatic and anti-angiogenic attributes.

Early-onset Cardiotoxicity assessment related to anthracycline in children with leukemia. A Prospective Study

Background:

Acute leukemias are the most frequent malignancies in children. Advances in treatment have improved the overall survival to 80%. Almost 10% of children with cancer develop clinical cardiac toxicity. Total anthracycline cumulative dose is a risk factor for early-onset cardiotoxicity.

Objective:

To describe the incidence of early-onset cardiotoxicity in children with acute leukemia treated with chemotherapy.

Methods:

A prospective descriptive study of patients >1 y and <18 years diagnosed with acute leukemia. Assessed with electrocardiograma, echocardiography, and blood biomarkers at diagnosis and during the follow-up.

Results:

94 patients with acute lymphoblastic leukemia and 18 with acute myeloid leukemia were included. 20 patients (17.9%) developed early-onset cardiotoxicity. Statistically significant data was seen after anthracycline dose >150 mg/m², between the first echocardiographic evaluation and posterior analyses in the left ventricular fraction ejection with Teicholz p 0.05, Simpson p 0.018 and GLS p 0.004. In this study, there was no relation between blood biomarkers and cardiotoxicity.

Conclusions:

Cancer therapeutic-related cardiac dysfunction is related to anthracycline cumulative dose. In this study, echocardiographic follow-up was useful to predict risk factors for early cardiac dysfunction.

The Prophylactic Effect of Pinocembrin Against Doxorubicin-Induced Cardiotoxicity in an In Vitro H9c2 Cell Model

Background

The clinical use of Doxorubicin (Dox) is significantly limited by its dose-dependent cardiotoxic side effect. Accumulative evidence suggests that the use of flavonoids, such as the antioxidative Pinocembrin (Pin), could be effective in the prevention of Dox-induced cardiotoxicity. Accordingly, we investigated the ability of pinocembrin (Pin) to attenuate Dox-induced cardiotoxicity in an in vitro H9c2 cardiomyoblast model.

Methodology

The cardioprotective potential of Pin was established in H9c2 cells. Here, cells were treated with Dox (2μM), Dox (2μM) + Pin (1μM), and Dox (2μM) + Dexrazoxane (20μM) for 6 days. Thereafter, the safe co-administration of Pin with Dox, in a cancer environment, was investigated in MCF-7 breast cancer cells subjected to the same experimental conditions. Untreated cells served as the control. Subsequently, Pin’s ability to attenuate Dox-mediated oxidative stress, impaired mitochondrial bioenergetics and potential, as well as aggravated apoptosis was quantified using biochemical assays.

Results

The results demonstrated that co-treatment with Pin mitigates Dox-induced oxidative stress by alleviating the antioxidant enzyme activity of the H9c2 cells. Pin further reduced the rate of apoptosis and necrosis inferred by Dox by improving mitochondrial bioenergetics. Interestingly, Pin did not decrease the efficacy of Dox but, rather increased the rate of apoptosis and necrosis in Dox-treated MCF-7 cells.

Conclusion

The findings presented in this study showed, for the first time, that Pin attenuates Dox-induced cardiotoxicity without reducing its chemotherapeutic effect. We propose that additional studies, using in vivo models, should be conducted to further investigate Pin as a suitable candidate in the prevention of the cardiovascular dysfunction inferred by Dox administration.

Cardiotoxicity - the first cause of morbidity and mortality in pediatric patients survivors of acute lymphoblastic leukemia

Acute lymphoblastic leukemia is the most common hematological malignancy at pediatric age. Cardiotoxicity holds the first place among the causes of morbidity and mortality in these patients. Anthracyclines are cytostatic drugs frequently associated with cardiotoxicity. Early diagnosis of cardiac impairment during the treatment of pediatric patients is extremely important, both for modulating future chemotherapy and for administering cardioprotective agents. Long term monitoring after chemotherapy helps to identify the risk of late cardiotoxicity among cancer survivors. There are several biomarkers, already in use or still under study, which may represent an operator-independent alternative for echocardiography in the diagnosis of cardiotoxicity. In case of cardiac damage, the clinician has options for treating or limiting the progression, either with the use of already approved agents, such as Dexrazoxane, or by administrating other cardioprotective drugs. International experts are still attempting to establish the best algorithm for early detection of cardiotoxicity, as well as the most efficient treatment plan in case of already existing myocardial damage in these patients. We present a review on treatment-related cardiotoxicity, including mechanisms of development, useful biomarkers and treatment options, after carefully analyzing specialty literature.

Cardiovascular Toxicities in Pediatric Cancer Survivors

Advances in cancer therapies have significantly improved patient outcomes. However, with improvements in survival, the toxicities associated with cancer therapy have become of paramount importance and oncologists are faced with the challenge of establishing therapeutic efficacy while minimizing toxicity. Cardiovascular disease represents a significant risk to survivors of childhood cancer and is a major cause of morbidity and mortality. This article outlines the current state of knowledge regarding cardiotoxicity in children undergoing cancer therapies, including the impact of specific oncologic therapies, recommendations for cardiovascular screening, the management of established cardiac disease, and the evolving field of pediatric cardio-oncology.

Magnetic Driven Nanocarriers for pH-Responsive Doxorubicin Release in Cancer Therapy

Doxorubicin is one of the most widely used anti-cancer drugs, but side effects and selectivity problems create a demand for alternative drug delivery systems. Herein we describe a hybrid magnetic nanomaterial as a pH-dependent doxorubicin release carrier. This nanocarrier comprises magnetic iron oxide cores with a diameter of 10 nm, enveloped in a hybrid material made of siliceous shells and ĸ-carrageenan. The hybrid shells possess high drug loading capacity and a favorable drug release profile, while the iron oxide cores allows easy manipulation via an external magnetic field. The pH responsiveness was assessed in phosphate buffers at pH levels equivalent to those of blood (pH 7.4) and tumor microenvironment (pH 4.2 and 5). The nanoparticles have a loading capacity of up to 12.3 wt.% and a release profile of 80% in 5 h at acidic pH versus 25% at blood pH. In vitro drug delivery tests on human breast cancer and non-cancer cellular cultures have shown that, compared to the free drug, the loaded nanocarriers have comparable antiproliferative effect but a less intense cytotoxic effect, especially in the non-cancer cell line. The results show a clear potential for these new hybrid nanomaterials as alternative drug carriers for doxorubicin.

Subclinical Cardiac Dysfunction in Childhood Cancer Survivors on 10-Years Follow-Up Correlates With Cumulative Anthracycline Dose and Is Best Detected by Cardiopulmonary Exercise Testing, Circulating Serum Biomarker, Speckle Tracking Echocardiography, and Tissue Doppler Imaging

Background: Survivors of childhood cancer are at risk for anthracycline- and/or radiotherapy-induced cardiotoxicity. Aims: The aim of this study was to assess clinical, laboratory, and imaging parameters of subclinical cardiovascular disease in childhood cancer survivors. Methods: Patients underwent cardiopulmonary exercise test (CPET), laboratory testing, transthoracic echocardiography (TTE) with tissue doppler imaging (TDI) and speckle tracking. A subset of patients also underwent cardiovascular magnetic resonance imaging (CMR). Findings were correlated to cumulative anthracycline and exposure to mediastinal irradiation during cancer treatment. In a subgroup analysis, TTE and CMR findings were compared to data from 40 gender- and age-matched patients with childhood onset hypertrophic cardiomyopathy (HCM). Results: Cardiac evaluation was performed in 79 patients (43 males) at 11.2 ± 4.5 years after cancer treatment. Oncologic diagnosis at a median age of 12.0 years was Hodgkin lymphoma in 20, sarcoma in 17, acute leukemia in 24, relapse leukemia in 10, and others in 8 patients. Cumulative anthracycline dose exceeded 300 mg/m² in 28 patients. Twenty six patients also received mediastinal irradiation. Decreased peak respiratory oxygen uptake in % predicted on CPET, increased levels of N-terminal pro-brain natriuretic peptide (NTproBNP), increased global longitudinal strain on TTE speckle tracking, and diastolic dysfunction on TDI were the most prominent findings on detailed cardiology follow-up. In contrast to HCM patients, childhood cancer survivors did not show left ventricular hypertrophy (LVPWd z-score median 0.9 vs. 2.8, p < 0.001), hyperdynamic systolic function on TTE (Ejection fraction 62 ± 7 vs. 72 ± 12%, p = 0.001), or fibrotic myocardial changes on CMR (Late gadolinium positive 0/13 vs. 13/36, p = 0.001; extracellular volume fraction 22 ± 2 vs. 28 ± 3, p < 0.001) at time of follow-up. There was no correlation between chest radiation exposure and abnormal cardiac findings. Cumulative anthracycline dose was the only significant independent predictor on multivariate analysis for any cardiovascular abnormality on follow-up (p = 0.036). Conclusion: Increasing cumulative anthracycline dose during cancer treatment correlates with subclinical cardiac dysfunction in childhood cancer survivors best detected by elevated cardiac serum biomarkers, decreased exercise capacity on CPET, and abnormalities on echocardiographic speckle tracking and TDI.

Teaching the basics of the mechanism of doxorubicin-induced cardiotoxicity: Have we been barking up the wrong tree?

Doxorubicin (DOX), or Adriamycin, an anthracycline antibiotic discovered serendipitously as a chemotherapeutic drug several decades ago, is still one of the most effective drugs for treating various adult and pediatric cancers (breast cancer, Hodgkin's disease, lymphoblastic leukemia). However, one of the major side effects of the continuous use of DOX is dose-dependent, long-term, and potentially lethal cardiovascular toxicity (congestive heart failure and cardiomyopathy) in cancer survivors many years after cessation of chemotherapy. In addition, predisposition to cardiotoxicity varied considerably among individuals. The long-held notion that DOX cardiotoxicity is caused by reactive oxygen species formed from the redox-cycling of DOX semiquinone lacks rigorous proof in a chronic animal model, and administration of reactive oxygen species detoxifying agents failed to reverse DOX-induced cardiac problems. In this review, I discuss the pros and cons of the reactive oxygen species pathway as a primary or secondary mechanism of DOX cardiotoxicity, the role of topoisomerases, and the potential use of mitochondrial-biogenesis-enhancing compounds in reversing DOX-induced cardiomyopathy. New approaches for well-designed clinical trials that repurpose FDA-approved drugs and naturally occurring polyphenolic compounds prophylactically to prevent or mitigate cardiovascular complications in both pediatric and adult cancer survivors are needed. Essentially, the focus should be on enhancing mitochondrial biogenesis to prevent or mitigate DOX-induced cardiotoxicity.

Aspirin ameliorates the long-term adverse effects of doxorubicin through suppression of cellular senescence

A number of childhood cancer survivors develop adverse, late onset side effects of earlier cancer treatments, known as the late effects of cancer therapy. As the number of survivors continues to increase, this growing population is at increased risk for a number of health-related problems. In the present study, we have examined the effect of aspirin on the late effects of chemotherapy by treating juvenile mice with doxorubicin (DOX). This novel mouse model produced various long-term adverse effects, some of which resemble premature aging phenotypes. DOX also resulted in the tissue accumulation of senescent cells and up-regulation of cyclooxygenase-2 (COX2) expression. However, treatment with aspirin following juvenile exposure to DOX improved body weight gain, ameliorated the long-term adverse effects, and reduced the levels of senescence markers. Moreover, aspirin reduced p53 and p21 accumulation in DOX-treated human and mouse fibroblasts. However, the suppressive effect of aspirin on DOX-induced p53 accumulation was significantly decreased in COX2 knockout mouse embryonic fibroblasts. Additionally, treatment of senescent fibroblasts with aspirin or celecoxib, a COX2 specific inhibitor, reduced cell viability and decreased the levels of Bcl-xL protein. Taken together, these studies suggest that aspirin may be able to reduce the late effects of chemotherapy through the suppression of cellular senescence.

Doxorubicin-Induced Cardiomyopathy in Children

Doxorubicin-induced cardiotoxicity in childhood cancer survivors is a growing problem. The population of patients at risk for cardiovascular disease is steadily increasing, as five-year survival rates for all types of childhood cancers continue to improve. Doxorubicin affects the developing heart differently from the adult heart and in a subset of exposed patients, childhood exposure leads to late, irreversible cardiomyopathy. Notably, the prevalence of late-onset toxicity is increasing in parallel with improved survival. By the year 2020, it is estimated that there will be 500,000 childhood cancer survivors and over 50,000 of them will suffer from doxorubicin-induced cardiotoxicity. The majority of the research to-date, concentrated on childhood cancer survivors, has focused mostly on clinical outcomes through well-designed epidemiological and retrospective cohort studies. Preclinical studies have elucidated many of the cellular mechanisms that elicit acute toxicity in cardiomyocytes. However, more research is needed in the areas of early- and late-onset cardiotoxicity and more importantly improving the scientific understanding of how other cells present in the cardiac milieu are impacted by doxorubicin exposure. The overall goal of this review is to succinctly summarize the major clinical and preclinical studies focused on doxorubicin-induced cardiotoxicity. As the prevalence of patients affected by doxorubicin exposure continues to increase, it is imperative that the major gaps in existing research are identified and subsequently utilized to develop appropriate research priorities for the coming years. Well-designed preclinical research models will enhance our understanding of the pathophysiology of doxorubicin-induced cardiotoxicity and directly lead to better diagnosis, treatment, and prevention. © 2019 American Physiological Society. Compr Physiol 9:905-931, 2019.

Transcriptomic profiling reveals p53 as a key regulator of doxorubicin-induced cardiotoxicity

Doxorubicin is an important anticancer drug in the clinic. Unfortunately, it causes cumulative and dose-dependent cardiotoxic side effects. As the population of cancer survivors who have been exposed to treatment continues to grow, there is increased interest in assessing the long-term cardiac effects of doxorubicin and understanding the underlying mechanisms at play. In this study, we investigated doxorubicin-induced transcriptomic changes using RNA-sequencing (RNAseq) and a cellular model comprised of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). Analyses of predicted upstream regulators identified the p53 protein as a key regulator of transcriptomic changes induced by doxorubicin. Clustering and pathway analyses showed that increased death receptor (DR) expression and enrichment of the extrinsic apoptotic pathway are significantly associated with doxorubicin-induced cardiotoxicity. Increased expression of p53 and DRs were confirmed via immunoblotting. Our data pinpoints increased DR expression as an early transcriptomic indicator of cardiotoxicity, suggesting that DR expression might function as a predictive biomarker for cardiac damage.

Identification of genetic association between cardiorespiratory fitness and the trainability genes in childhood acute lymphoblastic leukemia survivors

BACKGROUND

The progress of treatments of childhood acute lymphoblastic leukemia (ALL) has made it possible to reach a survival rate superior to 80%. However, the treatments lead to several long-term adverse effects, including cardiac toxicity. Although studies have reported associations between genetic variants and cardiorespiratory fitness, none has been performed on childhood ALL survivors.

METHODS

We performed whole-exome sequencing in 239 childhood ALL survivors from the PETALE cohort. Germline variants (both common and rare) in selected set of genes (N = 238) were analyzed for an association with cardiorespiratory fitness.

RESULTS

Our results showed that the common variant in the TTN gene was significantly associated with a low cardiorespiratory fitness level (p = 0.0005) and that the LEPR, IGFBPI and ENO3 genes were significantly associated with a low cardiorespiratory fitness level in female survivors (p ≤ 0.002). Also, we detected an association between the low cardiorespiratory fitness level in participants that were stratified to the "high risk" prognostic group and functionally predicted rare variants in the SLC22A16 gene (p = 0.001). Positive associations between cardiorespiratory fitness level and trainability genes were mainly observed in females.

CONCLUSIONS

For the first time, we observed that low cardiorespiratory fitness in childhood ALL survivors can be associated with variants in genes related to subjects' trainability. These findings could allow better childhood ALL patient follow-up tailored to their genetic profile and cardiorespiratory fitness, which could help reduce at least some of the burden of long-term adverse effects of treatments.

Engagement with tNOX (ENOX2) to Inhibit SIRT1 and Activate p53-Dependent and -Independent Apoptotic Pathways by Novel 4,11-Diaminoanthra[2,3-b]furan-5,10-diones in Hepatocellular Carcinoma Cells

Hepatocellular carcinoma (HCC) is the most frequent primary malignancy of the liver and is among the top three causes of cancer-associated death worldwide. However, the clinical use of chemotherapy for HCC has been limited by various challenges, emphasizing the urgent need for novel agents with improved anticancer properties. We recently synthesized and characterized a series of 4,11-diaminoanthra[2,3-b]furan-5,10-dione derivatives that exhibit potent apoptotic activity against an array of cancer cell lines, including variants with multidrug resistance. Their effect on liver cancer cells, however, was unknown. Here, we investigated three selected 4,11-diaminoanthra[2,3-b]furan-5,10-dione derivatives (compounds 1–3) for their cytotoxicity and the underlying molecular mechanisms in wild-type or p53-deficient HCC cells. Cytotoxicity was determined by WST-1 assays and cell impedance measurements and apoptosis was analyzed by flow cytometry. The interaction between compounds and tumor-associated NADH oxidase (tNOX, ENOX2) was studied by cellular thermal shift assay (CETSA). We found that compound 1 and 2 induced significant cytotoxicity in both HepG2 and Hep3B lines. CETSA revealed that compounds 1 and 2 directly engaged with tNOX, leading to a decrease in the cellular NAD⁺/NADH ratio. This decreased the NAD⁺-dependent activity of Sirtuin 1 (SIRT1) deacetylase. In p53-wild-type HepG2 cells, p53 acetylation/activation was enhanced, possibly due to the reduction in SIRT1 activity, and apoptosis was observed. In p53-deficient Hep3B cells, the reduction in SIRT1 activity increased the acetylation of c-Myc, thereby reactivating the TRAIL pathway and, ultimately leading to apoptosis. These compounds thus trigger apoptosis in both cell types, but via different pathways. Taken together, our data show that derivatives 1 and 2 of 4,11-diaminoanthra[2,3-b]furan-5,10-diones engage with tNOX and inhibit its oxidase activity. This results in cytotoxicity via apoptosis through tNOX-SIRT1 axis to enhance the acetylation of p53 or c-Myc in HCC cells, depending on their p53 status.

Anthracycline-associated cardiotoxicity in adults: systematic review on the cardioprotective role of beta-blockers

OBJECTIVES

This study aimed at assessing the role of beta-blockers on preventing anthracycline-induced cardiotoxicity in adults.

METHODS

A systematic review was performed on electronic databases, including relevant studies that analysed beta-blockers as cardioprotective agents before the use of anthracyclines by adult oncologic patients.

RESULTS

After application of eligibility and selection criteria, eight articles were considered as high quality, complying with the proposed theme; all eight clinical trials, four of them placebo-controlled, with a total number of 655 patients included. From this sample, 281 (42.9%) used beta-blocker as intervention, and carvedilol was the most frequent (167 patients - 25.5%). Six studies were considered positive regarding the cardioprotection role played by beta-blockers, although only four demonstrated significant difference on left ventricle ejection fraction after chemotherapy on groups that used beta-blockers compared to control groups. Carvedilol and nebivolol, but not metoprolol, had positive results regarding cardioprotection. Other beta-blockers were not analysed in the selected studies.

CONCLUSIONS

Despite the potential cardioprotective effect of beta-blockers, as demonstrated in small and unicentric clinical trials, its routine use on prevention of anthracycline-associated cardiotoxicity demands greater scientific evidence.

Quercetin Reverses Altered Energy Metabolism in the Heart of Rats Receiving Adriamycin Chemotherapy

The primary aim of this study was to find the potential modulatory roles of quercetin (QUE) against Adriamycin (ADR)-induced cardiotoxicity. A total of 50 rats were assigned to five groups: a control group, an ADR-treated group, a QUE-treated group, a prophylaxis-cotreated group, and a therapeutic-cotreated group, respectively. QUE exhibited a significant cardioprotective effect, particularly, when it was administered prior to and concurrently with ADR treatment (prophylaxis-cotreated group). This effect was biochemically evident by the significant decreases in the serum levels of myocardial injury biomarkers such as troponin, creatine kinase-myocardium bound, and creatine phosphokinase. In addition, significant elevations in myocardial antioxidant indices coupled with significant reductions in myocardial malondialdehyde contents and DNA damage, elicited by ADR injection, were observed. All these biochemical improvements were accompanied by a significant histopathological recovery and obvious modulation of the AMP-activated protein kinase (AMPK) signaling pathway by promoting the expression of the AMPKα2, PPARα, and PCG-1α genes. Taken together, these findings conclusively showed that QUE administration through its antioxidant capacity and myocardial energy metabolism restoration provides a prophylactic effect in response to ADR-induced deleterious effects, in the rat heart.

Avaliação econômica do uso de dexrazoxano na profilaxia de cardiotoxicidade em crianças em tratamento quimioterápico com antraciclinas

Resumo: O câncer em indivíduos de 0 a 19 anos é considerado raro, quando comparado à incidência em faixas etárias maiores, sendo estimado entre 2% e 3% de todos os tumores malignos registrados no Brasil. O uso de antraciclinas está frequentemente associado ao aparecimento de cardiotoxicidade e faz parte de aproximadamente 60% dos protocolos terapêuticos em oncologia pediátrica. Dentre as estratégias existentes para a prevenção de cardiotoxicidade, o dexrazoxano obteve resultados favoráveis pautados em desfechos intermediários (marcadores bioquímicos e medidas ecocardiográficas). Foi desenvolvida, neste trabalho, uma avaliação de custo-efetividade que compare o uso do dexrazoxano em diferentes populações, além de uma avaliação do impacto orçamentário causado pela possível incorporação da tecnologia. Foi utilizado o horizonte temporal de toda a vida do paciente e a perspectiva de análise do Sistema Único de Saúde. Uma análise de impacto orçamentário para cada tecnologia também foi construída. Após uma busca na literatura, foi desenvolvido um modelo de Markov capaz de comparar o uso do dexrazoxano em seis perfis de pacientes com risco de desenvolver cardiotoxicidade. Usar o medicamento nas crianças menores de cinco anos de idade se mostrou a alternativa mais custo-efetiva (razão de custo-efetividade incremental - RCEI de R$ 6.156,96), seguida de usar em todos os pacientes (RCEI de R$ 58.968,70). Caso o preço diminua a um valor menor que R$ 250,00 por frasco, a alternativa de usar em todas as crianças se torna a mais custo-efetiva. O impacto orçamentário ao final de cinco anos foi de R$ 30.622.404,81 para uso apenas nas crianças menores de cinco anos. Usar a tecnologia em todas as crianças produziria um impacto incremental de R$ 94.352.898,77.

The role of irradiated heart and left ventricular volumes in heart failure occurrence after childhood cancer

BACKGROUND

Paediatric cancer survivors have a high risk of developing cardiac diseases, and the most frequent cardiac disease is heart failure (HF). The radiation dose-volume effects in the heart and cardiac substructures have not been explored in childhood cancer survivors (CCS). Therefore, the role of irradiated heart volume in the occurrence of HF among this population remains unclear. The aims of this study were to determine the doses and irradiated volumes of the heart and left ventricle (LV) related to the risk of HF in CCS and to investigate the impact of anthracycline exposure on this risk.

METHODS AND RESULTS

A case-control study nested in the French Childhood Cancer Survivors Study cohort. The mean heart and left ventricular doses and volumes indicators were estimated by reconstruction of individual treatments. A total of 239 HF cases and 1042 matched controls were included. The median age of HF diagnosis was 25.1 years. The median volume of the heart that received ≥ 30 Gy was 61.1% for cases and 16.9% for controls. In patients who did not receive anthracycline, the risk of HF was increased 3.6-fold when less than 10% of the LV received ≥ 30 Gy when compared to patients who were not exposed to any cardiac radiation and anthracycline.

CONCLUSIONS

Small irradiated volumes of the heart or LV were significantly associated with HF risk. To the author's knowledge, this is the first study to report a dose-response relationship based on dose-volume indicators in CCS, which can be translated efficiently into current clinical practice.

Role of ACE inhibitors in anthracycline-induced cardiotoxicity: A randomized, double-blind, placebo-controlled trial

BACKGROUND

Several measures including drugs have been tried to reduce anthracycline cardiotoxicity. The lack of randomized trials prompted this study to assess the role of an angiotensin converting enzyme (ACE) inhibitor (enalapril) in anthracycline-induced cardiotoxicity in children with hematological malignancies.

METHODS

A randomized, double-blind, placebo-controlled trial was conducted on 84 patients with leukemia (41) and lymphoma (43) who received anthracyclines (doxorubicin and/or daunorubicin) at cumulative dose ≥200 mg/m² . The patients were randomized to receive either enalapril [group A (n = 44)] or placebo [group B (n = 40)] for 6 months. Left ventricular ejection fraction (LVEF) and cardiac biomarkers (cardiac troponin I [cTnI], probrain natriuretic peptide [proBNP], and creatine kinase MB [CK-MB]) were assessed at baseline and 6 months. The primary outcome was a measured decrease in LVEF (≥20%). Secondary outcome measures were changes in cardiac biomarkers and the development of heart failure or arrhythmias.

RESULTS

LVEF decreased in both groups at 6 months, more so in group B (62.25 ± 5.49 vs 56.15 ± 4.79, P < 0.001). A ≥20% decrease was seen in 3 patients in group B but none in group A (P = 0.21). Cardiac biomarkers increased more in group B at 6 months, and the increase was significant for proBNP (49.60 ± 35.97 vs 98.60 ± 54.24, P < 0.001) and cTnI (0.01 ± 0.00 vs 0.011 ± 0.003, P = 0.035) but not significant for CK-MB (1.08 ± 0.18 vs 1.21 ± 0.44, P = 0.079). In group A, 9.1% of the patients showed an increase in proBNP level ≥100 compared with 37.5% in group B (P < 0.001). No patient developed heart failure or arrhythmia.

CONCLUSION

Enalapril has a role in reducing cardiac toxicity after anthracycline administration.

Two-Dimensional Speckle Tracking Echocardiography-Derived Strain Measurements in Survivors of Childhood Cancer on Angiotensin Converting Enzyme Inhibition or Receptor Blockade

Speckle tracking echocardiography (STE)-derived strain indices are believed to detect early cardiac dysfunction in survivors of childhood cancer and have potential to identify patients who may benefit from early heart failure treatment. However, effects of heart failure treatment on STE-derived strain measurements in this population are unknown. The aim of this study was to assess STE-derived strain measurements in survivors of childhood cancer treated with angiotensin converting enzyme inhibition or receptor blockade (ACEi/ARB). Two-dimensional speckle tracking analysis was retrospectively performed on echocardiograms from childhood cancer survivors before and during therapy with ACEi/ARB. Global left ventricular longitudinal and circumferential strain (GLS and GCS) and strain rates (LSR and CSR) were assessed and correlated with conventional echocardiographic measures of function. In 22 childhood cancer survivors (median age: 14.8, range 6.4-21.6 years), mean GLS (- 13.83 ± 0.74% to - 15.94 ± 0.74%, p = 0.002), GCS (- 18.79 ± 1.21% to - 20.74 ± 0.84%, p = 0.027), LSR (- 0.78 ± 0.04 to - 0.88 ± 0.04 s^-1, p = 0.022), and CSR (- 1.08 ± 0.07 to - 1.21 ± 0.06 s^-1, p = 0.027) improved on therapy. Improvement in GLS was maintained for greater than 1 year on ACEi/ARB (p = 0.02). Measures of strain and strain rate correlated with standard echocardiographic measures of function and were reproducible. These findings support the use of ACEi/ARB to treat post-chemotherapy-related cardiovascular changes in childhood cancer survivors, provide proof-of-concept that STE-derived strain and strain rate may be used to reliably monitor cardiac function during therapy, and support continued investigation into the clinical benefit of strain measurements in this population.