Congestive heart failure during imatinib mesylate treatment

Mitochondrial Dysfunction in Cardiotoxicity Induced by BCR-ABL1 Tyrosine Kinase Inhibitors -Underlying Mechanisms, Detection, Potential Therapies

The advent of BCR-ABL tyrosine kinase inhibitors (TKIs) targeted therapy revolutionized the treatment of chronic myeloid leukemia (CML) patients. Mitochondria are the key organelles for the maintenance of myocardial tissue homeostasis. However, cardiotoxicity associated with BCR-ABL1 TKIs can directly or indirectly cause mitochondrial damage and dysfunction, playing a pivotal role in cardiomyocytes homeostatic system and putting the cancer survivors at higher risk. In this review, we summarize the cardiotoxicity caused by BCR-ABL1 TKIs and the underlying mechanisms, which contribute dominantly to the damage of mitochondrial structure and dysfunction: endoplasmic reticulum (ER) stress, mitochondrial stress, damage of myocardial cell mitochondrial respiratory chain, increased production of mitochondrial reactive oxygen species (ROS), and other kinases and other potential mechanisms of cardiotoxicity induced by BCR-ABL1 TKIs. Furthermore, detection and management of BCR-ABL1 TKIs will promote our rational use, and cardioprotection strategies based on mitochondria will improve our understanding of the cardiotoxicity from a mitochondrial perspective. Ultimately, we hope shed light on clinical decision-making. By integrate and learn from both research and practice, we will endeavor to minimize the mitochondria-mediated cardiotoxicity and reduce the adverse sequelae associated with BCR-ABL1 TKIs.

Chemotherapeutic-Induced Cardiovascular Dysfunction: Physiological Effects, Early Detection-The Role of Telomerase to Counteract Mitochondrial Defects and Oxidative Stress

Although chemotherapeutics can be highly effective at targeting malignancies, their ability to trigger cardiovascular morbidity is clinically significant. Chemotherapy can adversely affect cardiovascular physiology, resulting in the development of cardiomyopathy, heart failure and microvascular defects. Specifically, anthracyclines are known to cause an excessive buildup of free radical species and mitochondrial DNA damage (_mtDNA) that can lead to oxidative stress-induced cardiovascular apoptosis. Therefore, oncologists and cardiologists maintain a network of communication when dealing with patients during treatment in order to treat and prevent chemotherapy-induced cardiovascular damage; however, there is a need to discover more accurate biomarkers and therapeutics to combat and predict the onset of cardiovascular side effects. Telomerase, originally discovered to promote cellular proliferation, has recently emerged as a potential mechanism to counteract mitochondrial defects and restore healthy mitochondrial vascular phenotypes. This review details mechanisms currently used to assess cardiovascular damage, such as C-reactive protein (CRP) and troponin levels, while also unearthing recently researched biomarkers, including circulating _mtDNA, telomere length and telomerase activity. Further, we explore a potential role of telomerase in the mitigation of mitochondrial reactive oxygen species and maintenance of _mtDNA integrity. Telomerase activity presents a promising indicator for the early detection and treatment of chemotherapy-derived cardiac damage.

Imatinib attenuates cardiac fibrosis by inhibiting platelet-derived growth factor receptors activation in isoproterenol induced model

Cardiac fibrosis is a significant global health problem with limited treatment choices. Although previous studies have shown that imatinib (IMA) inhibited cardiac fibrosis, the anti-fibrotic mechanisms have not been clearly uncovered. The aim of this study is to evaluate whether IMA attenuates cardiac fibrosis by inhibiting platelet-derived growth factor receptors (PDGFR) on isoproterenol (ISO)-induced mice. Adult male C57BL/6 mice were treated with vehicle or ISO ± IMA for one week. After echocardiography examination, the hearts of mice were used for histopathologic, RT-qPCR, and western blot analyses. We found that the ventricular wall thickness, cardiac hypertrophy, and apoptosis were enhanced following ISO treatment. IMA decreased the left ventricular wall thickness, prevented hypertrophy, and inhibited apoptosis induced by ISO. In addition, IMA attenuated the accumulation of collagens and α-smooth muscle actin (α-SMA) (the markers of fibrosis) caused by ISO treatment. Moreover, the expression of fibrosis related genes, and the phosphorylation of PDGFRs in ISO-treated mice hearts were inhibited by IMA as well. However, IMA did not change the expression of the matrix metalloproteinase-9 (MMP-9) in ISO-treated hearts. Furthermore, IMA reduced the expressions of collagens as well as α-SMA caused by activation of PDGFRα in cardiac fibroblasts. Taken together, our data demonstrate that IMA attenuated the cardiac fibrosis by blocking the phosphorylation of PDGFRs in the ISO-induced mice model. This study indicates that IMA could be a potentially therapeutic option for cardiac fibrosis in clinical application.

Cardiovascular Toxicity and Management of Targeted Cancer Therapy

The advent of effective oral, molecular-targeted drugs in oncology has changed many incurable malignancies such as chronic myeloid leukemia into chronic diseases similar to coronary artery disease and diabetes mellitus. Oral agents including monoclonal antibodies, kinase inhibitors and hormone receptor blockers offer patients with cancer incremental improvements in both overall survival and quality of life. As it is imperative to recognize and manage side effects of platelet inhibitors, beta blockers, statins, human immunodeficiency virus drugs and fluoroquinolones by all healthcare providers, the same holds true for these newer targeted therapies; patients may present to their generalist or other subspecialist with drug-related symptoms. Cardiovascular adverse events are among the most frequent, and potentially serious, health issues in outpatient clinics, and among the most frequent side effects of targeted chemotherapy. Data support improved patient outcomes and satisfaction when primary care and other providers are cognizant of chemotherapy side effects, allowing for earlier intervention and reduction in morbidity and healthcare costs. With the implementation of accountable care and pay for performance, improved communication between generalists and subspecialists is essential to deliver cost-effective patient care.

Ageing is a risk factor in imatinib mesylate cardiotoxicity

AIMS

Chemotherapy-induced heart failure is increasingly recognized as a major clinical challenge. Cardiotoxicity of imatinib mesylate, a highly selective and effective anticancer drug belonging to the new class of tyrosine kinase inhibitors, is being reported in patients, some progressing to congestive heart failure. This represents an unanticipated challenge that could limit effective drug use. Understanding the mechanisms and risk factors of imatinib mesylate cardiotoxicity is crucial for prevention of cardiovascular complications in cancer patients.

METHODS AND RESULTS

We used genetically engineered mice and primary rat neonatal cardiomyocytes to analyse the action of imatinib on the heart. We found that treatment with imatinib (200 mg/kg/day for 5 weeks) leads to mitochondrial-dependent myocyte loss and cardiac dysfunction, as confirmed by electron microscopy, RNA analysis, and echocardiography. Imatinib cardiotoxicity was more severe in older mice, in part due to an age-dependent increase in oxidative stress. Mechanistically, depletion of the transcription factor GATA4 resulting in decreased levels of its prosurvival targets Bcl-2 and Bcl-XL was an underlying cause of imatinib toxicity. Consistent with this, GATA4 haploinsufficient mice were more susceptible to imatinib, and myocyte-specific up-regulation of GATA4 or Bcl-2 protected against drug-induced cardiotoxicity.

CONCLUSION

The results indicate that imatinib action on the heart targets cardiomyocytes and involves mitochondrial impairment and cell death that can be further aggravated by oxidative stress. This in turn offers a possible explanation for the current conflicting data regarding imatinib cardiotoxicity in cancer patients and suggests that cardiac monitoring of older patients receiving imatinib therapy may be especially warranted.

Pleural effusion in a patient with metastatic gastrointestinal stromal tumor treated with imatinib: case report

ABSTRACT 

Gastrointestinal stromal tumors are rare malignancies characterized by c-kit and PDGFR-α mutations targeted by imatinib. Pleural effusion is a very rare side effect of imatinib treatment. A 65-year-old female with metastatic gastrointestinal stromal tumor developed electrolyte imbalance, severe peripheral edema and progressively worsening dyspnea 2 months after starting imatinib. Having excluded cardiovascular and pulmonary disorders, imatinib was discontinued and prednisone 25 mg orally daily was begun. The patient's condition improved substantially over the next 48 h with a progressive decrease in dyspnea and a reduction in pleural effusion and peripheral edema. All side effects had resolved within 1 month. In view of the partial response obtained, the patient re-started imatinib after a 1-week interruption. Prednisone was maintained and there was no further toxicity.

Abl kinases are required for vascular function, Tie2 expression, and angiopoietin-1-mediated survival

Endothelial dysfunction is associated with diverse cardiovascular pathologies. Here, we show a previously unappreciated role for the Abelson (Abl) family kinases (Abl and Arg) in endothelial function and the regulation of angiogenic factor pathways important for vascular homeostasis. Endothelial Abl deletion in Arg-null mice led to late-stage embryonic and perinatal lethality, with mutant mice displaying focal loss of vasculature and tissue necrosis. Loss of Abl kinases led to increased endothelial cell apoptosis both in vitro and in vivo, contributing to vascular dysfunction, infarction, and tissue damage. Mechanistically, we identify a unique dual role for Abl kinases in the regulation of angiopoietin/Tie2 protein kinase signaling. Endothelial Abl kinases modulate Tie2 expression and angiopoietin-1-mediated endothelial cell survival. These findings reveal a critical requirement for the Abl kinases in vascular development and function, which may have important implications for the clinical use of Abl kinase inhibitors.

Imatinib-induced decompensated heart failure in an elderly patient with chronic myeloid leukemia: case report and literature review

Because it is safe and well tolerated, imatinib is a standard first-line therapy for chronic myeloid leukemia (CML). Although there have been sporadic reports of imatinib-induced cardiotoxicity, including left ventricle (LV) dysfunction and heart failure, the evidence for it is contradictory. Here, we reported a case of an 88-year-old male patient with CML developed decompensated heart failure following imatinib therapy. Four days after the initiation of imatinib, the patient developed orthopnea, edema and a pleural effusion accompanied by abdominal distension, nausea and vomiting. The chest X-ray film showed an enlarged cardiac profile. The echocardiogram demonstrated a decreased LV ejection fraction and enlarged left-side cardiac chambers. B-type natriuretic peptide concentrations were markedly increased. The patient recovered soon after the withdrawal of imatinib and introduction of comprehensive therapy for heart failure. Imatinib-induced cardiotoxicity in elderly patients is a potentially serious complication that merits further evaluation.

Detection and prevention of cardiac complications of cancer chemotherapy

Despite continuous improvements in management of patients with cancer, cardiac side-effects still account for a substantial limitation of chemotherapy. Evaluation of cardiac toxicity in patients includes consideration of biomarkers such as cardiac troponins and B-type natriuretic peptides, together with non-invasive imaging in the form of 2D-, 3D-, or strain-echocardiography, multiple gated radionuclide angiography, quantitative gated blood-pool SPECT, (123)I-metaiodobenzylguanidine scintigraphy, or cardiac magnetic resonance imaging. These approaches differ from each other with regards to availability, accuracy, sensitivity to detect early stages of cardiac injury, individual reliability, ease of use in a longitudinal follow-up perspective, and to related cost-effectiveness. Improving prevention of these cardiac side-effects depends on several, currently unresolved issues. Early detection and quantification of cardiac damage is required to adapt chemotherapy in progress for optimal management of patients. Whether increased availability of myocardial strain imaging and repeat blood biomarkers determinations will reliably and consistently achieve these goals remain to be confirmed. Also, protective approaches to reduce cardiac toxicity of anticancer drugs should be reconsidered according to the recently restricted approval for use of dexrazoxane. Anthracycline-based regimens, encapsulated anthracyclines and non-anthracycline regimens should be revisited with regards to antitumour efficacy and cardiac toxicity. Cardiovascular drugs that proved effective in prevention of anthracycline-induced cardiac toxicity in experimental models should be investigated in clinical trials. Finally, the efficacy of cardiovascular drugs that have already been tested in clinical settings should be confirmed and compared with each other in patients in increased numbers.

Clinical cardiac safety profile of nilotinib

BACKGROUND

Nilotinib is a second-generation tyrosine kinase inhibitor with significant efficacy as first- or second-line treatment in patients with chronic myeloid leukemia. Despite preclinical evidence indicating a risk of prolongation of the QT interval, which was confirmed in clinical trials, detailed information on nilotinib's cardiac safety profile is lacking.

DESIGN AND METHODS

Here, we retrospectively assessed cardiovascular risk factors in 81 patients who were being or had previously been treated with nilotinib therapy and evaluated cardiovascular parameters by longitudinal monitoring of the QT interval and left ventricular ejection fraction. Detailed information on the occurrence and management of defined cardiac adverse events was extracted.

RESULTS

The median duration of nilotinib therapy was 26 months (range, 1-72). The median QT interval at baseline was 413 msec (range, 368-499 msec). During follow-up, the median QT was not significantly different from the baseline value at any time-point. Sixteen of 81 patients (20%) had new electrocardiographic changes. Cardiac function, as assessed by measurement of left ventricular ejection fraction, did not change significantly from baseline at any time-point. During a median follow-up of 44 months (range, 2-73), seven patients (9%), all of whom had received prior imatinib therapy, developed 11 clinical cardiac adverse events requiring treatment. The median time from the start of nilotinib therapy to an event was 14.5 months (range, 2-68). Five of seven patients were able to continue nilotinib therapy with only one brief interruption.

CONCLUSIONS

Whereas new electrocardiographic abnormalities were recorded in 20% of all patients and some of them developed severe or even life-threatening coronary artery disease, QT prolongation, changes in left ventricular ejection fraction, and clinical cardiac adverse events were uncommon in patients treated with nilotinib.

ErbB signaling in cardiac development and disease

The ErbB family of receptor tyrosine kinases (RTKs) is a family of receptors that allow cells to interact with the extracellular environment and transduce signals to the nucleus that promote differentiation, migration and proliferation necessary for proper heart morphogenesis and function. This review focuses on the role of the ErbB family of receptor tyrosine kinases, and their importance in proper heart morphogenesis, as well as their role in maintenance and function of the adult heart. Studies from transgenic mouse models have shown the importance of ErbB receptors in heart development, and provide insight into potential future therapeutic targets to help reduce congenital heart defect (CHD) mortality rates and prevent disease in adults. Cancer therapeutics have also shed light to the ErbB receptors and signaling network, as undesired side effects have demonstrated their importance in adult cardiomyocytes and prevention of cardiomyopathies. This review will discuss ErbB receptor tyrosine kinases (RTK) in heart development and disease including valve formation and partitioning of a four-chambered heart as well as cardiotoxicity when ErbB signaling is attenuated in adults.

Cardiovascular side-effects of modern cancer therapy

Recent advances in chemotherapy have substantially improved the prognosis of cancer patients. However, many anticancer drugs, especially newly developed ;molecular-target drugs', such as the anti-HER2 blocking antibody and the anti-vascular endothelial growth factor antibody, have serious cardiovascular side-effects such as heart failure, thromboembolism, severe hypertension and lethal arrhythmia, which interrupt cancer treatment and decrease the patient's quality of life. Despite the increasing clinical significance, cardiologists have not been focusing enough of their attention on this issue. The major cardiovascular complications associated with anticancer drugs, and current diagnosis, treatment and prevention strategies are reviewed. Close collaborations between oncologists and cardiologists is necessary to tackle cardiovascular complications and advance cancer treatment.