Mechanisms of Cardiovascular Toxicity of BCR-ABL1 Tyrosine Kinase Inhibitors in Chronic Myelogenous Leukemia

The state of the art in secondary pharmacology and its impact on the safety of new medicines

Secondary pharmacology screening of investigational small-molecule drugs for potentially adverse off-target activities has become standard practice in pharmaceutical research and development, and regulatory agencies are increasingly requesting data on activity against targets with recognized adverse effect relationships. However, the screening strategies and target panels used by pharmaceutical companies may vary substantially. To help identify commonalities and differences, as well as to highlight opportunities for further optimization of secondary pharmacology assessment, we conducted a broad-ranging survey across 18 companies under the auspices of the DruSafe leadership group of the International Consortium for Innovation and Quality in Pharmaceutical Development. Based on our analysis of this survey and discussions and additional research within the group, we present here an overview of the current state of the art in secondary pharmacology screening. We discuss best practices, including additional safety-associated targets not covered by most current screening panels, and present approaches for interpreting and reporting off-target activities. We also provide an assessment of the safety impact of secondary pharmacology screening, and a perspective on opportunities and challenges in this rapidly developing field.

High sensitivity c-reactive protein and circulating biomarkers of endothelial dysfunction in patients with chronic myeloid leukemia receiving tyrosine kinase inhibitors

Tyrosine kinase inhibitors (TKIs) have revolutionized the management of patients with chronic myelogenous leukemia (CML); however, they may cause cardiovascular (CV) toxicities. In this cross-sectional study, we explored whether high-sensitivity C-reactive protein (hsCRP) and novel markers of vascular dysfunction were associated with exposure to specific TKIs, in 262 CML patients. Hs-CRP level was not associated with CML disease activity or treatment with a specific TKI. Body mass index (OR: 1.15, 95% CI: 1.108-1.246; p < 0.001) and CML duration (OR: 1.004, 95% CI: 1.001-1.008; p = 0.024) were independently associated with higher hs-CRP. In exploratory analyses, novel endothelial-centric markers (e.g. ET-1 and VCAM-1) were differential across the various TKIs, particularly amongst nilotinib- and ponatinib-treated patients. While Levels of hs-CRP do not appear to be correlated with specific TKIs, circulating markers of vascular dysfunction were altered in patients treated with specific TKIs and should be explored as potential markers of TKI-associated CV risk.

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.

Cardiovascular Toxicities Associated with Tyrosine Kinase Inhibitors

PURPOSE OF REVIEW

To provide a detailed overview of cardiovascular adverse events associated with the use of tyrosine kinase inhibitors across different tumor types.

RECENT FINDINGS

Despite an undeniable survival advantage of tyrosine kinase inhibitors (TKIs) in patients with hematologic or solid malignancies, the accompanying off-target cardiovascular adverse events can be life-threatening. In patients with B cell malignancies, the use of Bruton tyrosine kinase inhibitors has been associated with atrial and ventricular arrhythmias, as well as hypertension. Cardiovascular toxic profiles are heterogeneous among the several approved breakpoint cluster region (BCR)-ABL TKIS. Notably, imatinib might be cardioprotective. Vascular endothelial growth factor TKIs, constituting the central axis in the treatment of several solid tumors, including renal cell carcinoma and hepatocellular carcinoma, have strongly been associated with hypertension and arterial ischemic events. Epidermal growth factor TKIs as therapy for advanced non-small cell lung cancer (NSCLC) have been reported to be infrequently associated with heart failure and QT prolongation. While tyrosine kinase inhibitors have been demonstrated to increase overall survival across different types of cancers, special consideration should be given to cardiovascular toxicities. High-risk patients can be identified by undergoing a comprehensive workup at baseline.

Approaches to early diagnosis and prevention of cardiovascular toxicity induced by targeted drugs and immune checkpoint inhibitors in oncohematology: a literature review

The development of targeted drugs and immune checkpoint inhibitors (ICIs), as well as their implementation into clinical practice has allowed increasing the overall and event-free survival of oncohematological patients. Currently, assessment of the efficacy of a therapeutic strategy in each specific case includes the evaluation of an acceptable tolerability profile. The subject of discussion includes cardiovascular complications induced by target drugs and ICIs. The review mainly presents the issues of cardiovascular toxicity (CVT) in certain groups of oncohematological patients (with chronic lymphocytic leukemia, chronic myeloid leukemia, multiple myeloma). The spectrum of cardiovascular adverse effects associated with targeted and ICI therapy in oncohematological practice is quite wide — coronary artery disease, peripheral arterial disease, myocarditis, heart failure, arrhythmias, hypertension. The high importance of the problem of using targeted and immunosuppressive therapy dictates the need to predict adverse effects. The diagnosis of heart failure (one of CVT manifestations) is based on determining the decreased left ventricular ejection fraction during echocardiography, less often — during cardiac magnetic resonance imaging; global longitudinal myocardial strain is a significant parameter of preclinical heart failure, which is determined using the speckle tracking technique. To determine vascular toxicity, a special attention is paid to the vascular wall structure and microcirculation parameters — capillary density at rest, percentage of capillary recovery and perfused capillaries, stiffness index for large blood vessels, reflection index for small arteries, laboratory markers of inflammation and endothelial dysfunction (C-reactive protein, fibrinogen, homocysteine, endothelin 1, vascular endothelial growth factor). CVT prevention presumes the determination of the risk group, correction of risk factors, and administration of protective therapy to very high and high-risk patients. One of the promising directions for preventing vascular toxicity is the use of sodium-glucose linked transporter-2 inhibitors.

Inhibition of Soluble Epoxide Hydrolase Attenuates Bosutinib-Induced Blood Pressure Elevation

Supplemental Digital Content is available in the text.

Endothelial cells play a critical role in maintaining homeostasis of vascular function, and endothelial activation is involved in the initial step of atherogenesis. Previously, we reported that Abl kinase mediates shear stress–induced endothelial activation. Bosutinib, a dual inhibitor of Src and Abl kinases, exerts an atheroprotective effect; however, recent studies have demonstrated an increase in the incidence of side effects associated with bosutinib, including increased arterial blood pressure (BP). To understand the effects of bosutinib on BP regulation and the mechanistic basis for novel treatment strategies against vascular dysfunction, we generated a line of mice conditionally lacking c-Abl in endothelial cells (endothelial cell-Abl^KO). Knockout mice and their wild-type littermates (Abl^f/f) were orally administered a clinical dose of bosutinib, and their BP was monitored. Bosutinib treatment increased BP in both endothelial cell-Abl^KO and Abl^f/f mice. Furthermore, acetylcholine-evoked endothelium-dependent relaxation of the mesenteric arteries was impaired by bosutinib treatment. RNA sequencing of mesenteric arteries revealed that the CYP (cytochrome P450)-dependent metabolic pathway was involved in regulating BP after bosutinib treatment. Additionally, bosutinib treatment led to an upregulation of soluble epoxide hydrolase in the arteries and a lower plasma content of eicosanoid metabolites in the CYP pathway in mice. Treatment with 1-Trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea, a soluble epoxide hydrolase inhibitor, reversed the bosutinib-induced changes to the eicosanoid metabolite profile, endothelium-dependent vasorelaxation, and BP. Thus, the present study demonstrates that upregulation of soluble epoxide hydrolase mediates bosutinib-induced elevation of BP, independent of c-Abl. The addition of soluble epoxide hydrolase inhibitor in patients treated with bosutinib may aid in preventing vascular side effects.

Arterial hypertension assessment in a population with chronic myeloid leukemia

Treatment of chronic myeloid leukaemia (CML) is based on tyrosine kinase inhibitors (TKI), whose introduction in 2001 improved the survival rate after 5 years from 40 to 90%. The longevity increase has been accompanied by a higher incidence of cardiovascular events (CVE) that can be explained due to the sum of cardiovascular risk factors (CVRF) together with the secondary effects of the TKI. The effect of the TKI over the blood pressure control is still unknown. An observational cross-sectional study of patients with CML under treatment with TKI (imatinib, dasatinib and nilotinib) was conducted. Blood pressure was analyzed through sphygmomanometer and 24-h ambulatory blood pressure monitoring (ABPM). A total of 73 patients were included, 57 treated with a single line of treatment. 32.9% of the total of individuals under this study showed uncontrolled blood pressure according to the ABPM. The factors related to uncontrolled BP were overweight, dyslipidemia, alcohol use, pulse wave velocity a high/very high cardiovascular risk. The subjects who received treatment with nilotinib did present worse control of their blood pressure in ABPM than those treated with imatinib and dasatinib (p = 0.041). This finding could indicate that an uncontrolled blood pressure is implied in the pro-inflammatory and pro-atherogenic mechanism underlying the development of the cardiovascular disease in those patients under treatment with nilotinib. The ABPM is a useful tool in the diagnosis and treatment of HT, being the reason why it should be included in the assessment of patients with CML whose HT diagnosis proves uncertain.

Targeting HSPA8 inhibits proliferation via downregulating BCR-ABL and enhances chemosensitivity in imatinib-resistant chronic myeloid leukemia cells

The resistance to tyrosine kinase inhibitors is currently a major problem for chronic myeloid leukemia (CML) treatment and HSPA8 is highly expressed and a hallmark of poor prognosis in several human cancers. However, its role in imatinib-resistant CML (IR-CML) cells remains undetermined. Here, we determined HSPA8 was overexpressed in IR-CML cells and associated with imatinib resistance. HSPA8 ablation could downregulate BCR-ABL/STAT5 and BCR-ABL/AKT signaling pathways, dramatically induce proliferation inhibition, autophagy, G0/G1 phase cell cycle arrest but not apoptosis in IR-CML cells. Significantly, HSPA8 ablation enhanced the antitumor activity of imatinib via promoting apoptosis in vitro and vivo. These findings unraveled that HSPA8 ablation inhibits proliferation via downregulating BCR-ABL and enhances chemosensitivity of imatinib in IR-CML cells, which investigate the role and molecular mechanism of HSPA8 in IR-CML cells and suggest that HSPA8 may be a potential target for IR-CML treatment.

Risk of Thrombosis in Adult Philadelphia-Positive ALL Treated with an Asparaginase-Free ALL Regimen

BACKGROUND

venous thromboembolism (VTE) is a well-known complication in adults with acute lymphoblastic leukemia (ALL), especially in patients treated with asparaginase (ASNase)-including regiments. However, VTE risk in adult Philadelphia-positive ALL (Ph+ve ALL) patients treated with non-hyperCVAD chemotherapy is unclear. In this study, we examined VTE incidence in adult Ph+ve ALL patients treated with imatinib plus a pediatric-inspired asparaginase (ASNase)-free regimen modified from the Dana Farber Cancer Institute (DFCI) ALL protocol.

METHODS

a single centre retrospective review of Ph+ve ALL patients treated at Princess Margaret Cancer Center (PMCC) from 2008-2019 with imatinib plus modified DFCI protocol was conducted.

RESULTS

of the 123 patients included, 30 (24.3%) had at least 1 radiology confirmed VTE event from diagnosis to the end of maintenance therapy. 86.7% (26/30) of the VTE events occurred during active treatment. Of all VTE events, the majority (53.3%) were DVT and/or PE while another significant portion were catheter-related (40.0%). Major bleeding was observed in 1 patient on VTE treatment with low molecular weight heparin (LMWH).

CONCLUSION

a high VTE incidence (24.3%) was observed in adults Ph+ve ALL patients treated with imatinib plus an ASNase-free modified DFCI pediatric ALL protocol, suggesting prophylactic anticoagulation should be considered for all adult Ph+ve ALL patients including those treated with ASNase-free regimens.