Management of Cancer Therapeutics-Related Cardiac Dysfunction

The Role of p90 Ribosomal S6 Kinase (RSK) in Tyrosine Kinase Inhibitor (TKI)-Induced Cardiotoxicity

Targeted therapy, such as tyrosine kinase inhibitors (TKIs), has been approved to manage various cancer types. However, TKI-induced cardiotoxicity is a limiting factor for their use. This issue has raised the need for investigating potential cardioprotective techniques to be combined with TKIs. Ribosomal S6-kinases (RSKs) are a downstream effector of the mitogen-activated-protein-kinase (MAPK) pathway; specific RSK isoforms, such as RSK1 and RSK2, have been expressed in cancer cells, in which they increase tumour proliferation. Selective targeting of those isoforms would result in tumour suppression. Moreover, activation of RSKs expressed in the heart has resulted in cardiac hypertrophy and arrhythmia; thus, inhibiting RSKs would result in cardio-protection. This review article presents an overview of the usefulness of RSK inhibitors that can be novel agents to be assessed in future research for their effect in reducing cancer proliferation, as well as protecting the heart from cardiotoxicity induced by TKIs.

Global longitudinal strain assessment in contrast-enhanced echocardiography in breast cancer patients: a feasibility study

BACKGROUND

Left ventricular global longitudinal strain (GLS) obtained from two-dimensional speckle-tracking echocardiography (2D-STE) can reflect cancer therapy-related cardiac dysfunction in breast cancer (BC) patients, however, the accuracy and reproducibility of 2D-STE are restricted due to poor image quality.

METHODS

Between January 2019 and October 2021, 160 consecutive BC patients aged ≥ 18 years were recruited. The 160 BC patients (mean age: 48.41 ± 9.93 years, 100% women) underwent both 2D-STE and Contrast-enhanced echocardiography (CEcho), 125 of whom were included in the measurement of GLS. The intraclass correlation coefficient (ICC) was used to determine the intra- and inter-observer reproducibility of 2D-STE and CEcho-STE. Correlation (r) was calculated using Pearson correlation. Statistical significance was set at P < 0.05.

RESULTS

Among 160 BC patients, more segments were recognized by CEcho-STE than by 2D-STE (2,771, 99.53% vs. 2,440, 84.72%). The left ventricular ejection fraction (LVEF) obtained by 2D was lower than CEcho (61.75 ± 6.59% vs. 64.14 ± 5.97%, P < 0.0001). The GLS obtained by 2D-STE was lower than CEcho-STE (-21.74 ± 2.77% vs. -26.79 ± 4.30%, P = 0.001). The ICC of the intraobserver and interobserver agreements in the CEcho-STE group was lower than that in the 2D-STE group. GLS measurements were in good agreement between the 2D-STE and CEcho-STE groups (r = 0.773).

CONCLUSIONS

CEcho can overcome some imaging limitations and recognize more segments than 2D, which may provide an LVEF and GLS closer to the true value. Based on AutoStrain, CEcho-STE may serve as a complementary method for those with poor image quality.

Disclosing an In-Frame Deletion of the Titin Gene as the Possible Predisposing Factor of Anthracycline-Induced Cardiomyopathy: A Case Report

Anthracycline-induced cardiomyopathy has been noted as a non-neglectable issue in the field of clinical oncology. Remarkable progress has been achieved in searching for inherited susceptible genetic deficits underlying anthracycline cardiotoxicity in the past several years. In this case report, we present the preliminary results of a genetic study in a young male patient who was treated with standard dose anthracycline-based chemotherapy for his acute myeloid leukemia and attacked by acute congestive heart failure after just two courses of therapy. After a survey of 76 target genes, an in-frame deletion of the titin gene was recognized as the most possible genetic defect responsible for his cardiomyopathy caused by anthracycline. This defect proved to pass down from the patient′s mother and did not exist in seven unrelated chemotherapy-treated cancer patients without chemotherapy-induced cardiomyopathy and four other healthy volunteer DNA donors.

Successful Management of Osimertinib-Induced Heart Failure

Cancer therapeutics-related cardiac dysfunction is currently of great concern as one of the pivotal therapeutic targets of onco-cardiology. Only a few studies have reported the occurrence of heart failure following the administration of osimertinib, a third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor for EGFR mutation-positive advanced non-small cell lung cancer. We report on a 74-year-old woman with osimertinib-induced advanced heart failure with reduced ejection fraction, which was treated by the temporal termination of osimertinib and neurohormonal blocker therapy, as well as heart rate modulation therapy using ivabradine. Despite osimertinib-induced heart failure being relatively rare, aggressive neurohormonal blocker therapy using ivabradine if applicable, as well as the temporal termination of osimertinib, might be a promising therapeutic strategy.

Investigation of the Antiremodeling Effects of Losartan, Mirabegron and Their Combination on the Development of Doxorubicin-Induced Chronic Cardiotoxicity in a Rat Model

Despite the effectiveness of doxorubicin (DOXO) as a chemotherapeutic agent, dose-dependent development of chronic cardiotoxicity limits its application. The angiotensin-II receptor blocker losartan is commonly used to treat cardiac remodeling of various etiologies. The beta-3 adrenergic receptor agonist mirabegron was reported to improve chronic heart failure. Here we investigated the effects of losartan, mirabegron and their combination on the development of DOXO-induced chronic cardiotoxicity. Male Wistar rats were divided into five groups: (i) control; (ii) DOXO-only; (iii) losartan-treated DOXO; (iv) mirabegron-treated DOXO; (v) losartan plus mirabegron-treated DOXO groups. The treatments started 5 weeks after DOXO administration. At week 8, echocardiography was performed. At week 9, left ventricles were prepared for histology, qRT-PCR, and Western blot measurements. Losartan improved diastolic but not systolic dysfunction and ameliorated SERCA2a repression in our DOXO-induced cardiotoxicity model. The DOXO-induced overexpression of Il1 and Il6 was markedly decreased by losartan and mirabegron. Mirabegron and the combination treatment improved systolic and diastolic dysfunction and significantly decreased overexpression of Smad2 and Smad3 in our DOXO-induced cardiotoxicity model. Only mirabegron reduced DOXO-induced cardiac fibrosis significantly. Mirabegron and its combination with losartan seem to be promising therapeutic tools against DOXO-induced chronic cardiotoxicity.

New Concept of Onco-Hypertension and Future Perspectives

Owing to aging populations, the prevalence of hypertension and associated cardiovascular events has been increasing worldwide. The morbidity and mortality due to cancer have also been increasing with aging populations. Several small-molecule inhibitors have been used in cancer therapy, which have a positive impact on the prognosis and survival of patients with cancer. Consequently, the number of cancer survivors with hypertension has been rapidly increasing. Anticancer therapy, including vascular endothelial growth factor inhibitors, increases blood pressure. However, both clinical and laboratory evidence are lacking regarding optimal blood pressure control in patients with hypertension with cancer. Here, we propose the concept of onco-hypertension, which is an evolving subspecialty focused on the complex pathophysiology of hypertension and cancer. In this review, we highlight blood pressure changes in cancer, hypertension induced by anticancer therapy, and optimal blood pressure management in patients with hypertension with cancer. In addition, we discuss needed studies to further establish this new onco-hypertension concept.

Genetic Variants Associated With Cancer Therapy-Induced Cardiomyopathy

BACKGROUND

Cancer therapy-induced cardiomyopathy (CCM) is associated with cumulative drug exposures and preexisting cardiovascular disorders. These parameters incompletely account for substantial interindividual susceptibility to CCM. We hypothesized that rare variants in cardiomyopathy genes contribute to CCM.

METHODS

We studied 213 patients with CCM from 3 cohorts: retrospectively recruited adults with diverse cancers (n=99), prospectively phenotyped adults with breast cancer (n=73), and prospectively phenotyped children with acute myeloid leukemia (n=41). Cardiomyopathy genes, including 9 prespecified genes, were sequenced. The prevalence of rare variants was compared between CCM cohorts and The Cancer Genome Atlas participants (n=2053), healthy volunteers (n=445), and an ancestry-matched reference population. Clinical characteristics and outcomes were assessed and stratified by genotypes. A prevalent CCM genotype was modeled in anthracycline-treated mice.

RESULTS

CCM was diagnosed 0.4 to 9 years after chemotherapy; 90% of these patients received anthracyclines. Adult patients with CCM had cardiovascular risk factors similar to the US population. Among 9 prioritized genes, patients with CCM had more rare protein-altering variants than comparative cohorts ( P≤1.98e-04). Titin-truncating variants (TTNtvs) predominated, occurring in 7.5% of patients with CCM versus 1.1% of The Cancer Genome Atlas participants ( P=7.36e-08), 0.7% of healthy volunteers ( P=3.42e-06), and 0.6% of the reference population ( P=5.87e-14). Adult patients who had CCM with TTNtvs experienced more heart failure and atrial fibrillation ( P=0.003) and impaired myocardial recovery ( P=0.03) than those without. Consistent with human data, anthracycline-treated TTNtv mice and isolated TTNtv cardiomyocytes showed sustained contractile dysfunction unlike wild-type ( P=0.0004 and P<0.002, respectively).

CONCLUSIONS

Unrecognized rare variants in cardiomyopathy-associated genes, particularly TTNtvs, increased the risk for CCM in children and adults, and adverse cardiac events in adults. Genotype, along with cumulative chemotherapy dosage and traditional cardiovascular risk factors, improves the identification of patients who have cancer at highest risk for CCM.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifiers: NCT01173341; AAML1031; NCT01371981.