The Anti-Cancer Multikinase Inhibitor Sorafenib Impairs Cardiac Contractility by Reducing Phospholamban Phosphorylation and Sarcoplasmic Calcium Transients

Sorafenib induces cachexia by impeding transcriptional signaling of the SET1/MLL complex on muscle-specific genes

Chemotherapeutics used in cancer therapy are often linked to muscle wasting or cachexia. Insights into the molecular basis of chemotherapy-induced cachexia is essential to improve treatment strategies. Here, we demonstrated that Sorafenib-tyrosine kinase inhibitor (TKI) class of chemotherapeutic agents-induced cachexia. System-wide analyses revealed that Sorafenib alters the global transcriptional program and proteostasis in muscle cells. Mechanistically, Sorafenib treatment reduced active epigenetic mark H3K4 methylation on distinct muscle-specific genes by impeding chromatin association of SET1A-catalytic component of the SET1/MLL histone methyltransferase complex. This mechanism favored transcriptional disorientation that led to disrupted sarcomere assembly, calcium homeostasis and mitochondrial respiration. Consequently, the contractile ability of muscle cells was severely compromised. Interestingly, the other prominent TKIs Nilotinib and Imatinib did not exert similar effects on muscle cell physiology. Collectively, we identified an unanticipated transcriptional mechanism underlying Sorafenib-induced cachexia. Our findings hold the potential to strategize therapy regimens to minimize chemotherapy-induced cachexia.

A fatal case of cabozantinib-induced cardiomyopathy

Cabozantinib, a multi-kinase receptor inhibitor, is utilized in the treatment of advanced malignancies such as metastatic renal cancers. While rare, cabozantinib-induced cardiotoxicity has emerged as a recognized adverse effect with potentially reversible outcomes. We report the case of a 55-year-old male who developed fatal cardiomyopathy 4 months after initiating cabozantinib therapy. Despite its rarity, cardiomyopathy after initiation of cabozantinib can be lethal if not diagnosed early. This case underscores a significant gap in the surveillance of patients treated with newer agents like cabozantinib. Larger observational studies are needed to assess the prevalence and impact of cardiomyopathy after initiation of cabozantinib therapy, and to determine the cost-effectiveness of early surveillance protocols.

Sodium-Glucose Co-Transporter-2 Inhibitor Empagliflozin Attenuates Sorafenib-Induced Myocardial Inflammation and Toxicity

Environmental antineoplastics such as sorafenib may pose a risk to humans through water recycling, and the increased risk of cardiotoxicity is a clinical issue in sorafenib users. Thus, developing strategies to prevent sorafenib cardiotoxicity is an urgent work. Empagliflozin, as a sodium-glucose co-transporter-2 (SGLT2) inhibitor for type 2 diabetes control, has been approved for heart failure therapy. Still, its cardioprotective effect in the experimental model of sorafenib cardiotoxicity has not yet been reported. Real-time quantitative RT-PCR (qRT-PCR), immunoblot, and immunohistochemical analyses were applied to study the effect of sorafenib exposure on cardiac SGLT2 expression. The impact of empagliflozin on cell viability was investigated in the sorafenib-treated cardiomyocytes using Alamar blue assay. Immunoblot analysis was employed to delineate the effect of sorafenib and empagliflozin on ferroptosis/proinflammatory signaling in cardiomyocytes. Ferroptosis/DNA damage/fibrosis/inflammation of myocardial tissues was studied in mice with a 28-day sorafenib ± empagliflozin treatment using histological analyses. Sorafenib exposure significantly promoted SGLT2 upregulation in cardiomyocytes and mouse hearts. Empagliflozin treatment significantly attenuated the sorafenib-induced cytotoxicity/DNA damage/fibrosis in cardiomyocytes and mouse hearts. Moreover, GPX4/xCT-dependent ferroptosis as an inducer for releasing high mobility group box 1 (HMGB1) was also blocked by empagliflozin administration in the sorafenib-treated cardiomyocytes and myocardial tissues. Furthermore, empagliflozin treatment significantly inhibited the sorafenib-promoted NFκB/HMGB1 axis in cardiomyocytes and myocardial tissues, and sorafenib-stimulated proinflammatory signaling (TNF-α/IL-1β/IL-6) was repressed by empagliflozin administration. Finally, empagliflozin treatment significantly attenuated the sorafenib-promoted macrophage recruitments in mouse hearts. In conclusion, empagliflozin may act as a cardioprotective agent for humans under sorafenib exposure by modulating ferroptosis/DNA damage/fibrosis/inflammation. However, further clinical evidence is required to support this preclinical finding.

Proposal for considerations during human iPSC-derived cardiac organoid generation for cardiotoxicity drug testing

Human iPSC-derived cardiac organoids (hiPSC-COs) for cardiotoxicity drug testing via the variety of cell lines and unestablished protocols may lead to differences in response results due to a lack of criteria for generation period and size. To ensure reliable drug testing, it is important for researchers to set optimal generation period and size of COs according to the cell line and protocol applied in their studies. Hence, we sought to propose a process to establish minimum criteria for the generation duration and size of hiPSC-COs for cardiotoxic drug testing. We generated hiPSC-COs of different sizes based on our protocol and continuously monitored organoids until they indicated a minimal beating rate change as a control that could lead to more accurate beating rate changes on drug testing. Calcium transients and physiological tests to assess the functionality of hiPSC-COs on selected generation period, which showed regular cardiac beating, and immunostaining assays to compare characteristics were performed. We explained the generation period and size that exhibited and maintained regular beating rate changes on hiPSC-COs, and lead to reliable response results to cardiotoxicity drugs. We anticipate that this study will offer valuable insights into considering the appropriate generation period and size of hiPSC-COs ensuring reliable outcomes in cardiotoxicity drug testing.

Adverse effects of tyrosine kinase inhibitors in cancer therapy: pathophysiology, mechanisms and clinical management

Since their invention in the early 2000s, tyrosine kinase inhibitors (TKIs) have gained prominence as the most effective pathway-directed anti-cancer agents. TKIs have shown significant utility in the treatment of multiple hematological malignancies and solid tumors, including chronic myelogenous leukemia, non-small cell lung cancers, gastrointestinal stromal tumors, and HER2-positive breast cancers. Given their widespread applications, an increasing frequency of TKI-induced adverse effects has been reported. Although TKIs are known to affect multiple organs in the body including the lungs, liver, gastrointestinal tract, kidneys, thyroid, blood, and skin, cardiac involvement accounts for some of the most serious complications. The most frequently reported cardiovascular side effects range from hypertension, atrial fibrillation, reduced cardiac function, and heart failure to sudden death. The potential mechanisms of these side effects are unclear, leading to critical knowledge gaps in the development of effective therapy and treatment guidelines. There are limited data to infer the best clinical approaches for the early detection and therapeutic modulation of TKI-induced side effects, and universal consensus regarding various management guidelines is yet to be reached. In this state-of-the-art review, we examine multiple pre-clinical and clinical studies and curate evidence on the pathophysiology, mechanisms, and clinical management of these adverse reactions. We expect that this review will provide researchers and allied healthcare providers with the most up-to-date information on the pathophysiology, natural history, risk stratification, and management of emerging TKI-induced side effects in cancer patients.

Ca2+-Dependent Effects of the Selenium-Sorafenib Nanocomplex on Glioblastoma Cells and Astrocytes of the Cerebral Cortex: Anticancer Agent and Cytoprotector

Despite the fact that sorafenib is recommended for the treatment of oncological diseases of the liver, kidneys, and thyroid gland, and recently it has been used for combination therapy of brain cancer of various genesis, there are still significant problems for its widespread and effective use. Among these problems, the presence of the blood-brain barrier of the brain and the need to use high doses of sorafenib, the existence of mechanisms for the redistribution of sorafenib and its release in the brain tissue, as well as the high resistance of gliomas and glioblastomas to therapy should be considered the main ones. Therefore, there is a need to create new methods for delivering sorafenib to brain tumors, enhancing the therapeutic potential of sorafenib and reducing the cytotoxic effects of active compounds on the healthy environment of tumors, and ideally, increasing the survival of healthy cells during therapy. Using vitality tests, fluorescence microscopy, and molecular biology methods, we showed that the selenium-sorafenib (SeSo) nanocomplex, at relatively low concentrations, is able to bypass the mechanisms of glioblastoma cell chemoresistance and to induce apoptosis through Ca²⁺-dependent induction of endoplasmic reticulum stress, changes in the expression of selenoproteins and selenium-containing proteins, as well as key kinases-regulators of oncogenicity and cell death. Selenium nanoparticles (SeNPs) also have a high anticancer efficacy in glioblastomas, but are less selective, since SeSo in cortical astrocytes causes a more pronounced activation of the cytoprotective pathways.

Merits of hiPSC-Derived Cardiomyocytes for In Vitro Research and Testing Drug Toxicity

The progress of medical technology and scientific advances in the field of anticancer treatment have increased the survival probabilities and duration of life of patients. However, cancer-therapy-induced cardiac dysfunction remains a clinically salient problem. Effective anticancer therapies may eventually induce cardiomyopathy. To date, several studies have focused on the mechanisms underlying cancer-treatment-related cardiotoxicity. Cardiomyocyte cell lines with no contractile physiological characteristics cannot adequately model “true” human cardiomyocytes. However, applying “true” human cardiomyocytes for research is fraught with many obstacles (e.g., invasiveness of the procedure), and there is a proliferative limitation for rodent primary cultures. Human-induced pluripotent stem-cell-differentiated cardiomyocytes (hiPSC-CMs), which can be produced efficiently, are viable candidates for mimicking human cardiomyocytes in vitro. We successfully performed cardiac differentiation of human iPSCs to obtain hiPSC-CMs. These hiPSC-CMs can be used to investigate the pathophysiological basis and molecular mechanism of cancer-treatment-related cardiotoxicity and to develop novel strategies to prevent and rescue such cardiotoxicity. We propose that hiPSC-CMs can be used as an in vitro drug screening platform to study targeted cancer-therapy-related cardiotoxicity.

Kir2.1 dysfunction at the sarcolemma and the sarcoplasmic reticulum causes arrhythmias in a mouse model of Andersen-Tawil syndrome type 1

Andersen-Tawil syndrome type 1 (ATS1) is associated with life-threatening arrhythmias of unknown mechanism. In this study, we generated and characterized a mouse model of ATS1 carrying the trafficking-deficient mutant Kir2.1Δ314-315 channel. The mutant mouse recapitulates the electrophysiological phenotype of ATS1, with QT prolongation exacerbated by flecainide or isoproterenol, drug-induced QRS prolongation, increased vulnerability to reentrant arrhythmias and multifocal discharges resembling catecholaminergic polymorphic ventricular tachycardia (CPVT). Kir2.1Δ314-315 cardiomyocytes display significantly reduced inward rectifier K+ and Na+ currents, depolarized resting membrane potential and prolonged action potentials. We show that, in wild-type mouse cardiomyocytes and skeletal muscle cells, Kir2.1 channels localize to sarcoplasmic reticulum (SR) microdomains, contributing to intracellular Ca2+ homeostasis. Kir2.1Δ314-315 cardiomyocytes exhibit defective SR Kir2.1 localization and function, as intact and permeabilized Kir2.1Δ314-315 cardiomyocytes display abnormal spontaneous Ca2+ release events. Overall, defective Kir2.1 channel function at the sarcolemma and the SR explain the life-threatening arrhythmias in ATS1 and its overlap with CPVT.

Treatment effects of the EGFR pathway drugs on head and neck cancer stem cells

(1) Head and neck cancer (HNC) is the sixth most common cancer worldwide and show low survival rates and drug resistance, which can be due to the presence of cancer stem cells (CSCs), a small cell population with metastatic potential, invasion and self-renewal ability. (2) Here, seven tumor cells were sorted as CD44+/CD117+/CD133+ or ALDH+, considered as HNC stem cells (HNCSCs), and as CD44-/CD117-/CD133- or ALDH-, considered non-HNCSCs after both cells sorted criteria was compared to evaluate cell migration, invasion, and colony forming assays. These subpopulations were treated with Cetuximab, Paclitaxel, or a combination of both drugs and evaluated for cell viability. Quantitative PCR and western blot were performed to evaluate EGFR, TRKB, KRAS and HIF-1α gene and protein expression. (3) HNCSCs presented more colonies and appeared to be more sensitive to the drug combination when compared with non-HNCSCs, regardless cells sorted criteria and primary tumor subsite. The EGFR, TRKB, KRAS and HIF-1α genes and proteins were upregulated in CSCs compared with non-HNCSCs, thus explaining the drug resistance. (4) This study contributes to the better development of specific therapeutic protocols based on Cetuximab and Paclitaxel drugs in the treatment of HNC in the presence of CSCs and cell proliferation biomarkers.

Hesperetin mitigates sorafenib-induced cardiotoxicity in mice through inhibition of the TLR4/NLRP3 signaling pathway

Sorafenib is an oral multi-kinase receptor inhibitor that targets various signaling pathways. It is used as the first line of treatment in advanced hepatocellular and renal cell carcinomas. Sorafenib was reported to induce cardiotoxicity due to myocyte necrosis. Hesperetin is a naturally occurring flavonoid with antioxidant and anti-inflammatory capabilities. This study investigated the putative protective effect of hesperetin against sorafenib-induced cardiotoxicity in mice through downregulation of NLRP3/TLR4 signaling and inhibition of apoptosis. Twenty-four male Swiss mice were distributed into four groups: untreated control, hesperetin (50 mg/kg/day, orally), sorafenib (100 mg/kg/day, orally), and combination (Hesperetin+Sorafenib). After a three-week treatment period, various biochemical parameters in cardiac tissues were assessed. TNF-α, IL-1β, and IL-6 levels were measured. Moreover, TLR4 and NLRP3 expressions were evaluated using Western blot analysis. Histopathological examination and immunohistochemical assessment of apoptotic activity were done. Compared with the sorafenib group, the combination group exhibited reduced TNF-α, IL-1β, IL-6 levels and lower NLRP3/TLR4 expressions. Histologically, the combination group showed improved myocardial histology and a marked decrease in collagen deposition. Immunohistochemical examination showed decreased caspase-3 and increased Bcl-2 expression. Before recommending hesperetin as an adjuvant, clinical studies are warranted for mitigating sorafenib cardiotoxicity.

Comparative Analysis of the Cytotoxic Effect of a Complex of Selenium Nanoparticles Doped with Sorafenib, "Naked" Selenium Nanoparticles, and Sorafenib on Human Hepatocyte Carcinoma HepG2 Cells

Despite the use of sorafenib as one of the most effective drugs for the treatment of liver cancer, its significant limitations remain-poor solubility, the need to use high doses with the ensuing complications on healthy tissues and organs, and the formation of cell resistance to the drug. At the same time, there is more and more convincing evidence of the anticancer effect of selenium-containing compounds and nanoparticles. The aim of this work was to develop a selenium-sorafenib nanocomplex and study the molecular mechanisms of its anticancer effect on human hepatocyte carcinoma cells, where nanoselenium is not only a sorafenib transporter, but also an active compound. We have created a selenium-sorafenib nanocomplex based on selenium nanoparticles with size 100 nm. Using vitality tests, fluorescence microscopy, and PCR analysis, it was possible to show that selenium nanoparticles, both by themselves and doped with sorafenib, have a pronounced pro-apoptotic effect on HepG2 cells with an efficiency many times greater than that of sorafenib (So). "Naked" selenium nanoparticles (SeNPs) and the selenium-sorafenib nanocomplex (SeSo), already after 24 h of exposure, lead to the induction of the early stages of apoptosis with the transition to the later stages with an increase in the incubation time up to 48 h. At the same time, sorafenib, at the studied concentrations, began to exert a proapoptotic effect only after 48 h. Under the action of SeNPs and SeSo, both classical pathways of apoptosis induction and ER-stress-dependent pathways involving Ca2+ ions are activated. Thus, sorafenib did not cause the generation of Ca2+ signals by HepG2 cells, while SeNPs and SeSo led to the activation of the Ca2+ signaling system of cells. At the same time, the selenium-sorafenib nanocomplex turned out to be more effective in activating the Ca2+ signaling system of cells, inducing apoptosis and ER stress by an average of 20-25% compared to "naked" selenium nanoparticles. Our data on the mechanisms of action and the created nanocomplex are promising as a platform for the creation of highly selective and effective drugs with targeted delivery to tumors.

Cardio-oncology in Austria: cardiotoxicity and surveillance of anti-cancer therapies : Position paper of the Heart Failure Working Group of the Austrian Society of Cardiology

Survival in cancer is continuously improving due to evolving oncological treatment. Therefore, cardiovascular short-term and long-term side effects gain crucial importance for overall outcome. Cardiotoxicity not only presents as heart failure, but also as treatment-resistant hypertension, acute coronary ischemia with plaque rupture or vasospasm, thromboembolism, arrhythmia, pulmonary hypertension, diastolic dysfunction, acute myocarditis and others. Recent recommendations have proposed baseline cardiac risk assessment and surveillance strategies. Major challenges are the availability of monitoring and imaging resources, including echocardiography with speckle tracking longitudinal strain (GLS), serum biomarkers such as natriuretic peptides (NT-proBNP) and highly sensitive cardiac troponins. This Austrian consensus encompasses cardiotoxicity occurrence in frequent antiproliferative cancer drugs, radiotherapy, immune checkpoint inhibitors and cardiac follow-up considerations in cancer survivors in the context of the Austrian healthcare setting. It is important to optimize cardiovascular risk factors and pre-existing cardiac diseases without delaying oncological treatment. If left ventricular ejection fraction (LVEF) deteriorates during cancer treatment (from >10% to <50%), or myocardial strain decreases (>15% change in GLS), early initiation of cardioprotective therapies (angiotensin-converting enzyme inhibitors, angiotensin or beta receptor blockers) is recommended, and LVEF should be reassessed before discontinuation. Lower LVEF cut-offs were recently shown to be feasible in breast cancer patients to enable optimal anticancer treatment. Interdisciplinary cardio-oncology cooperation is pivotal for optimal management of cancer patients.

Oxidative stress in anticancer therapies-related cardiac dysfunction

Redox abnormalities are at the crossroad of cardiovascular diseases, cancer and cardiotoxicity from anticancer treatments. Indeed, disturbances of the redox equilibrium are common drivers of these conditions. Not only is an increase in oxidative stress a fundamental mechanism of action of anthracyclines (which have historically been the most studied anticancer treatments) but also this is at the basis of the toxic cardiovascular effects of antineoplastic targeted drugs and radiotherapy. Here we examine the oxidative mechanisms involved in the different cardiotoxicities induced by the main redox-based antineoplastic treatments, and discuss novel approaches for the treatment of such toxicities.

Structural and Electrophysiological Changes in a Model of Cardiotoxicity Induced by Anthracycline Combined With Trastuzumab

Background

Combined treatment with anthracyclines (e.g., doxorubicin; Dox) and trastuzumab (Trz), a humanized anti-human epidermal growth factor receptor 2 (HER2; ErbB2) antibody, in patients with HER2-positive cancer is limited by cardiotoxicity, as manifested by contractile dysfunction and arrhythmia. The respective roles of the two agents in the cardiotoxicity of the combined therapy are incompletely understood.

Objective

To assess cardiac performance, T-tubule organization, electrophysiological changes and intracellular Ca²⁺ handling in cardiac myocytes (CMs) using an in vivo rat model of Dox/Trz-related cardiotoxicity.

Methods and Results

Adult rats received 6 doses of either Dox or Trz, or the two agents sequentially. Dox-mediated left ventricular (LV) dysfunction was aggravated by Trz administration. Dox treatment, but not Trz, induced T-tubule disarray. Moreover, Dox, but not Trz monotherapy, induced prolonged action potential duration (APD), increased incidence of delayed afterdepolarizations (DADs) and beat-to-beat variability of repolarization (BVR), and slower Ca²⁺ transient decay. Although APD, DADs, BVR and Ca²⁺ transient decay recovered over time after the cessation of Dox treatment, subsequent Trz administration exacerbated these abnormalities. Trz, but not Dox, reduced Ca²⁺ transient amplitude and SR Ca²⁺ content, although only Dox treatment was associated with SERCA downregulation. Finally, Dox treatment increased Ca²⁺ spark frequency, resting Ca²⁺ waves, sarcoplasmic reticulum (SR) Ca²⁺ leak, and long-lasting Ca²⁺ release events (so-called Ca²⁺ “embers”), partially reproduced by Trz treatment.

Conclusion

These results suggest that in vivo Dox but not Trz administration causes T-tubule disarray and pronounced changes in electrical activity of CMs. While adaptive changes may account for normal AP shape and reduced DADs late after Dox administration, subsequent Trz administration interferes with such adaptive changes. Intracellular Ca²⁺ handling was differently affected by Dox and Trz treatment, leading to SR instability in both cases. These findings illustrate the specific roles of Dox and Trz, and their interactions in cardiotoxicity and arrhythmogenicity.

Mechanobiology Assays with Applications in Cardiomyocyte Biology and Cardiotoxicity

Cardiomyocytes are the motor units that drive the contraction and relaxation of the heart. Traditionally, testing of drugs for cardiotoxic effects has relied on primary cardiomyocytes from animal models and focused on short-term, electrophysiological, and arrhythmogenic effects. However, primary cardiomyocytes present challenges arising from their limited viability in culture, and tissue from animal models suffers from a mismatch in their physiology to that of human heart muscle. Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) can address these challenges. They also offer the potential to study not only electrophysiological effects but also changes in cardiomyocyte contractile and mechanical function in response to cardiotoxic drugs. With growing recognition of the long-term cardiotoxic effects of some drugs on subcellular structure and function, there is increasing interest in using hiPSC-CMs for in vitro cardiotoxicity studies. This review provides a brief overview of techniques that can be used to quantify changes in the active force that cardiomyocytes generate and variations in their inherent stiffness in response to cardiotoxic drugs. It concludes by discussing the application of these tools in understanding how cardiotoxic drugs directly impact the mechanobiology of cardiomyocytes and how cardiomyocytes sense and respond to mechanical load at the cellular level.

Assessment of Treatment With Sorafenib Plus Doxorubicin vs Sorafenib Alone in Patients With Advanced Hepatocellular Carcinoma: Phase 3 CALGB 80802 Randomized Clinical Trial

IMPORTANCE

Previous communication has reported significant improvement in overall survival (OS) when using doxorubicin plus sorafenib in the treatment of advanced hepatocellular cancer (HCC).

OBJECTIVE

To determine if doxorubicin added to sorafenib therapy improves OS, with stratification for locally advanced and metastatic disease.

DESIGN, SETTING, AND PARTICIPANTS

This unblinded randomized phase 3 clinical trial was led by Alliance in collaboration with Eastern Cooperative Oncology Group-American College of Radiology Imaging Network, Canadian Cancer Trials Group, and Southwest Oncology Group. It was launched in February 2010 and completed in May 2015; data were also analyzed during this time frame. Patients with histologically proven advanced HCC, no prior systemic therapy, Child-Pugh grade A score, Eastern Cooperative Oncology Group performance status of 0 to 2 (later amended to 0-1), and adequate hematologic, hepatic, renal, and cardiac function were eligible. The OS primary end point had a final analysis planned with 364 events observed among 480 total patients with 90% power to detect a 37% increase in median OS.

INTERVENTIONS OR EXPOSURES

Patients received either 60 mg/m2 of doxorubicin every 21 days plus 400 mg of sorafenib orally twice daily or the sorafenib alone, adjusted to half doses for patients with bilirubin levels of 1.3 to 3.0 mg/dL.

MAIN OUTCOMES AND MEASURES

The primary end point was OS, and progression-free survival (PFS) was a secondary end point.

RESULTS

Of 356 patients included in the study, the mean (SD) age was 62 (10.1) years, and 306 (86.0%) were men. Although it was planned to include 480 patients, the study was halted after accrual of 356 patients (180 patients treated with doxorubicin plus sorafenib and 176 with sorafenib alone) with a futility boundary crossed at a planned interim analysis. Median OS was 9.3 months (95% CI, 7.3-10.8 months) in the doxorubicin plus sorafenib arm and 9.4 months (95% CI, 7.3-12.9 months) in the sorafenib alone arm (hazard ratio, 1.05; 95% CI, 0.83-1.31). The median PFS was 4.0 months (95% CI, 3.4-4.9 months) in the doxorubicin plus sorafenib arm and 3.7 months (95% CI, 2.9-4.5 months) in the sorafenib alone arm (hazard ratio, 0.93; 95% CI, 0.75-1.16). Grade 3 or 4 neutropenia and thrombocytopenia adverse events occurred in 61 (36.8%) and 29 (17.5%) patients, respectively, being treated with doxorubicin plus sorafenib vs 1 (0.6%) and 4 (2.4%) patients treated with sorafenib.

CONCLUSIONS AND RELEVANCE

This multigroup study of the addition of doxorubicin to sorafenib therapy did not show improvement of OS or PFS in patients with HCC.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01015833.

Sorafenib- Taurine Combination Model for Hepatocellular Carcinoma Cells: Immunological Aspects

Sorafenib (Sor) is a multi-kinase inhibitor. It is recommended for the treatment of advanced hepatocellular carcinoma (HCC). However, Sor has severe and marked side effects. On the other hand, taurine (Tau) has been shown to enhance the therapeutic effects of cancer chemotherapy and also to enhance the function of leukocytes.

Here, we aimed to investigate the enhancing efficacy of Sor as well as minimizing its marked side effects by using Tau in combination in an immunological aspect. We evaluated the influence of Sor and Tau combination on the expression pattern of FOXP3 gene in HepG2 cells compared to peripheral blood mononuclear leukocytes (PBMCs) as control normal cells. Also, the levels of TGF-β and IL-10 released in culture media of both cells were determined. Our results revealed that, Tau reduced cytotoxicity of Sor on PBMC indicated by lactic dehyrogenase (LDH) release assay. In addition, Sor-Tau combination led to FOXP3 down-regulation in hepatic cancer cells (HepG2). The results showed also that, TGF-β levels decreased significantly in their culture media. In contrary, the cytokine increased in PBMCs culture media. Moreover, IL-10 was significantly elevated in the culture media of both cells. This study could open new avenues for the improvement of therapeutic efficacy of Sorafenib treated HCC patients by using Tau in combination.

Downregulation of miR-146a Contributes to Cardiac Dysfunction Induced by the Tyrosine Kinase Inhibitor Sunitinib

The main adverse effect of tyrosine kinase inhibitors, such as sunitinib, is cardiac contractile dysfunction; however, the molecular mechanisms of this effect remain largely obscure. MicroRNAs (miRNAs) are key regulatory factors in both cardiovascular diseases and the tyrosine kinase pathway. Therefore, we analyzed the differential expression of miRNAs in the myocardium in mice after exposure to sunitinib using miRNA microarray. A significant downregulation of miR-146a was observed in the myocardium of sunitinib-treated mice, along with a 20% decrease in left ventricle ejection fraction (LVEF). The downregulation of miR-146a was further validated by RT-qPCR. Among the potential targets of miR-146a, we focused on Pln and Ank2, which are closely related to cardiac contractile dysfunction. Results of luciferase reporter assay confirmed that miR-146a directly targeted the 3′ untranslated region of Pln and Ank2. Significant upregulation of PLN and ANK2 at the mRNA and protein levels was observed in the myocardium of sunitinib-treated mice. Cardiac-specific overexpression of miR-146a prevented the deteriorate effect of SNT on calcium transients, thereby alleviating the decreased contractility of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). SiRNA knockdown of PLN or ANK2 prevented sunitinib-induced suppression of contractility in hiPSC-CMs. Therefore, our in vivo and in vitro results showed that sunitinib downregulated miR-146a, which contributes to cardiac contractile dysfunction by regulating the downstream targets PLN and ANK2, and that upregulation of miR-146a alleviated the inhibitory effect of SNT on cardiac contractility. Thus, miR-146a could be a useful protective agent against sunitinib-induced cardiac dysfunction.

Heart Failure and Cancer: Mechanisms of Old and New Cardiotoxic Drugs in Cancer Patients

Although there have been many improvements in prognosis for patients with cancer, anticancer therapies are burdened by the risk of cardiovascular toxicity. Heart failure is one of the most dramatic clinical expressions of cardiotoxicity, and it may occur acutely or appear years after treatment. This article reviews the main mechanisms and clinical presentations of left ventricular dysfunction induced by some old and new cardiotoxic drugs in cancer patients, referring to the most recent advances in the field. The authors describe the mechanisms of cardiotoxicity induced by anthracyclines, which can lead to cardiovascular problems in up to 48% of patients who take them. The authors also describe mechanisms of cardiotoxicity induced by biological drugs that produce left ventricular dysfunction through secondary mechanisms. They outline the recent advances in immunotherapies, which have revolutionised anticancer therapies.

4-Amino-2-Trifluoromethyl-Phenyl Retinate induced leukemia cell differentiation by decreasing eIF6

4-Amino-2-Trifluoromethyl-Phenyl Retinate (ATPR), an all-trans retinoic acid (ATRA) derivative, possesses the ability to relief several carcinoma. Here, we explored the potential molecular mechanism of eukaryotic translation initiation factor 6 (eIF6) in ATPR-induced leukemia cell differentiation. Our research showed that ATPR could inhibit cell proliferation and promote cell differentiation in several leukemia cell lines. Besides, ATPR remarkably reduced the expression of eIF6 in vitro. Interestingly, the reduction of eIF6 contributed to restraining proliferation of K562 cells by inhibiting CyclinD1, C-myc and blocking cell cycle, as well as promoting differentiation of K562 cells by increasing the expression of C/EBPε, cell surface antigen CD11b and inducing renal-shrinkage of nuclear. Furthermore, the over-expression of eIF6 restrained the effects of ATPR on cell proliferation and maturation in K562 cells. In Addition, Notch1/CBF-1 signal activated by Chrysin could increase expression of eIF6 and restrain the differentiation in ATPR-induced K562 cells. Taken together, all above results indicated that ATPR induced differentiation of leukemia cells by decreasing eIF6 through Notch1/CBF-1 signal, which might exert an innovative treatment for leukemia.

Will iPSC-cardiomyocytes revolutionize the discovery of drugs for heart disease?

Cardiovascular disease remains the largest single cause of mortality in the Western world, despite significant advances in clinical management over the years. Unfortunately, the development of new cardiovascular medicines is stagnating and can in part be attributed to the difficulty of screening for novel therapeutic strategies due to a lack of suitable models. The advent of human induced pluripotent stem cells and the ability to make limitless numbers of cardiomyocytes could revolutionize heart disease modeling and drug discovery. This review summarizes the state of the art in the field, describes the strengths and weaknesses of the technology, and applications where the model system would be most appropriate.