Ccn2 Deletion Reduces Cardiac Dysfunction, Oxidative Markers, and Fibrosis Induced by Doxorubicin Administration in Mice.

Cellular Communication Network Factor 2 (CCN2) is a matricellular protein implicated in cell communication and microenvironmental signaling. Overexpression of CCN2 has been documented in various cardiovascular pathologies, wherein it may exert either deleterious or protective effects depending on the pathological context, thereby suggesting that its role in the cardiovascular system is not yet fully elucidated. In this study, we aimed to investigate the effects of Ccn2 gene deletion on the progression of acute cardiac injury induced by doxorubicin (DOX), a widely utilized chemotherapeutic agent. To this end, we employed conditional knockout (KO) mice for the Ccn2 gene (CCN2-KO), which were administered DOX and compared to DOX-treated wild-type (WT) control mice. Our findings demonstrated that the ablation of CCN2 ameliorated DOX-induced cardiac dysfunction, as evidenced by improvements in ejection fraction (EF) and fractional shortening (FS) of the left ventricle. Furthermore, DOX-treated CCN2-KO mice exhibited a significant reduction in the gene expression and activation of oxidative stress markers (Hmox1 and Nfe2l2/NRF2) relative to DOX-treated WT controls. Additionally, the deletion of Ccn2 markedly attenuated DOX-induced cardiac fibrosis. Collectively, these results suggest that CCN2 plays a pivotal role in the pathogenesis of DOX-mediated cardiotoxicity by modulating oxidative stress and fibrotic pathways. These findings provide a novel avenue for future investigations to explore the therapeutic potential of targeting CCN2 in the prevention of DOX-induced cardiac dysfunction.

Multiscale mapping of transcriptomic signatures for cardiotoxic drugs.

Drug-induced gene expression profiles can identify potential mechanisms of toxicity. We focus on obtaining signatures for cardiotoxicity of FDA-approved tyrosine kinase inhibitors (TKIs) in human induced-pluripotent-stem-cell-derived cardiomyocytes, using bulk transcriptomic profiles. We use singular value decomposition to identify drug-selective patterns across cell lines obtained from multiple healthy human subjects. Cellular pathways affected by cardiotoxic TKIs include energy metabolism, contractile, and extracellular matrix dynamics. Projecting these pathways to published single cell expression profiles indicates that TKI responses can be evoked in both cardiomyocytes and fibroblasts. Integration of transcriptomic outlier analysis with whole genomic sequencing of our six cell lines enables us to correctly reidentify a genomic variant causally linked to anthracycline-induced cardiotoxicity and predict genomic variants potentially associated with TKI-induced cardiotoxicity. We conclude that mRNA expression profiles when integrated with publicly available genomic, pathway, and single cell transcriptomic datasets, provide multiscale signatures for cardiotoxicity that could be used for drug development and patient stratification.

Adenylate cyclase 1 knockdown attenuates pirarubicin-induced cardiotoxicity.

This study aimed to investigate the effects and possible mechanisms of adenylate cyclase 1 (ADCY1) on pirarubicin-induced cardiomyocyte injury. HL-1 cells were treated with pirarubicin (THP) to induce intracellular toxicity, and the extent of damage to mouse cardiomyocytes was assessed using CCK-8, Edu, flow cytometry, ROS, ELISA, RT-qPCR and western blotting. THP treatment reduced the viability of HL-1 cells, inhibited proliferation, induced apoptosis and triggered oxidative stress. In addition, the RT-qPCR results revealed that ADCY1 expression was significantly elevated in HL-1 cells, and molecular docking showed a direct interaction between ADCY1 and THP. Western blotting showed that ADCY1, phospho-protein kinase A and GRIN2D expression were also significantly elevated. Knockdown of ADCY1 attenuated THP-induced cardiotoxicity, possibly by regulating the ADCY1/PKA/GRIN2D pathway.

CREG1 attenuates doxorubicin-induced cardiotoxicity by inhibiting the ferroptosis of cardiomyocytes.

OBJECTIVE: Doxorubicin (DOX)-induced cardiotoxicity limits the application of DOX in cancer patients. Currently, there is no effective prevention or treatment for DOX-induced cardiotoxicity. The cellular repressor of E1A-stimulated genes (CREG1) is a cardioprotective factor that plays an important role in the maintenance of cardiomyocytes differentiation and homeostasis. However, the role and mechanism of CREG1 in DOX-induced cardiotoxicity has not yet been elucidated. METHODS: In vivo, C57BL/6J mice, CREG1 transgenic and cardiac-specific CREG1 knockout mice were used to establish a DOX-induced cardiotoxicity model. H&E staining, Masson's trichrome, WGA staining, real-time PCR, and western blotting were performed to examine fibrosis and ferroptosis in the myocardium. In vitro, neonatal mouse cardiomyocytes (NMCMs) were cultured and stimulated with DOX, CREG1-overexpressed adenovirus, and small interfering RNA was used to establish CREG1 overexpression or knockdown cardiomyocytes. Transcriptomics, real-time PCR, western blotting, and immunoprecipitation were used to examine the roles and mechanisms of CREG1 in cardiomyocytes ferroptosis. RESULTS: The mRNA and protein levels of CREG1 were reduced in the hearts and NMCMs after DOX treatment. CREG1 overexpression alleviated myocardial damage and inhibited DOX-induced ferroptosis in the myocardium. CREG1 deficiency in the heart aggravated DOX-induced cardiotoxicity and ferroptosis. In vitro, CREG1 overexpression inhibited cardiomyocytes ferroptosis induced by DOX, and CREG1 knockdown aggravated DOX-induced cardiotoxicity. Mechanistically, CREG1 inhibited the mRNA and protein expression of pyruvate dehydrogenase kinase 4 (PDK4) by regulating the F-box and WD repeat domain containing 7 (FBXW7)-forkhead box O1 (FOXO1) pathway. PDK4 deficiency reversed the effects of CREG1 knockdown on cardiomyocytes ferroptosis following DOX treatment. CONCLUSION: CREG1 alleviated DOX-induced cardiotoxicity by inhibiting ferroptosis in cardiomyocytes. Our findings may help clarify the new roles of CREG1 in the development of DOX-induced cardiotoxicity.

Targeting OGF/OGFR signal to mitigate doxorubicin-induced cardiotoxicity.

Enkephalins are reportedly correlated with heart function. However, their regulation in the heart remains unexplored. This study revealed a substantial increase in circulating levels of opioid growth factor (OGF) (also known as methionine enkephalin) and myocardial expression levels of both OGF and its receptor (OGFR) in subjects treated with doxorubicin (Dox). Silencing OGFR through gene knockout or using adeno-associated virus serotype 9 carrying small hairpin RNA effectively alleviated Dox-induced cardiotoxicity (DIC) in mice. Conversely, OGF supplementation exacerbated DIC manifestations, which could be abolished by administration of the OGFR antagonist naltrexone (NTX). Mechanistically, the previously characterized OGF/OGFR/P21 axis was identified to facilitate DIC-related cardiomyocyte apoptosis. Additionally, OGFR was observed to dissociate STAT1 from the promoters of ferritin genes (FTH and FTL), thereby repressing their transcription and exacerbating DIC-related cardiomyocyte ferroptosis. To circumvent the compromised therapeutic effects of Dox on tumors owing to OGFR blockade, SiO2-based modifiable lipid nanoparticles were developed for heart-targeted delivery of NTX. The pretreatment of tumor-bearing mice with the assembled NTX nanodrug successfully provided cardioprotection against Dox toxicity without affecting Dox therapy in tumors. Taken together, this study provides a novel understanding of Dox cardiotoxicity and sheds light on the development of cardioprotectants for patients with tumors receiving Dox treatment.

Downregulating miR-432-5p exacerbates adriamycin-induced cardiotoxicity via activating the RTN3 signaling pathway.

BACKGROUND: Adriamycin (ADR) is a widely used chemotherapy drug in clinical practice and it causes toxicity in the myocardium affecting its clinical use. miR-432-5p is a miRNA primarily expressed in myocardial cells and has a protective effect in the myocardium. We aim to explore the protective effect of miR-432-5p on ADR-caused impaired mitochondrial ATP metabolism and endoplasmic reticulum stress (ERs). METHOD: The primary cardiomyocytes were obtained from neonatal mice and the ADR was added to cells, meanwhile, a mice model was constructed through intravenous ADR challenge, and expression levels of miR-432-5p were examined. Subsequently, the miR-432-5p was introduced in vitro and in vivo to explore its effect on the activity of mitochondrial ATP synthesis, autophagy, and ER stress. The bioinformatics analysis was performed to explore the target of miR-432-5p. RESULTS: ADR decreased the expression of miR-432-5p in cardiomyocytes. It also decreases mitochondrial ATP production and activates the ER stress pathway by increasing the expression of LC3B, Beclin 1, cleaved caspase 3, and induces cardiac toxicity. miR-432-5p exogenous supplementation can reduce the cardiotoxicity caused by ADR, and its protective effect on cardiomyocytes depends on the down-regulation of the RTN3 signaling pathway in ER. CONCLUSION: ADR can induce the low expression of miR-432-5p, and activate the RTN3 pathway in ER, increase the expression of LC3B, Beclin 1, cleaved caspase 3, CHOP, and RTN3, and induce cardiac toxicity.

H3K27ac acts as a molecular switch for doxorubicin-induced activation of cardiotoxic genes.

BACKGROUND: Doxorubicin (Dox) is an effective chemotherapeutic drug for various cancers, but its clinical application is limited by severe cardiotoxicity. Dox treatment can transcriptionally activate multiple cardiotoxicity-associated genes in cardiomyocytes, the mechanisms underlying this global gene activation remain poorly understood. METHODS AND RESULTS: Herein, we integrated data from animal models, CUT&Tag and RNA-seq after Dox treatment, and discovered that the level of H3K27ac (a histone modification associated with gene activation) significantly increased in cardiomyocytes following Dox treatment. C646, an inhibitor of histone acetyltransferase, reversed Dox-induced H3K27ac accumulation in cardiomyocytes, which subsequently prevented the increase of Dox-induced DNA damage and apoptosis. Furthermore, C646 alleviated cardiac dysfunction in Dox-treated mice by restoring ejection fraction and reversing fractional shortening percentages. Additionally, Dox treatment increased H3K27ac deposition at the promoters of multiple cardiotoxic genes including Bax, Fas and Bnip3, resulting in their up-regulation. Moreover, the deposition of H3K27ac at cardiotoxicity-related genes exhibited a broad feature across the genome. Based on the deposition of H3K27ac and mRNA expression levels, several potential genes that might contribute to Dox-induced cardiotoxicity were predicted. Finally, the up-regulation of H3K27ac-regulated cardiotoxic genes upon Dox treatment is conservative across species. CONCLUSIONS: Taken together, Dox-induced epigenetic modification, specifically H3K27ac, acts as a molecular switch for the activation of robust cardiotoxicity-related genes, leading to cardiomyocyte death and cardiac dysfunction. These findings provide new insights into the relationship between Dox-induced cardiotoxicity and epigenetic regulation, and identify H3K27ac as a potential target for the prevention and treatment of Dox-induced cardiotoxicity.

Circ-0006332 stimulates cardiomyocyte pyroptosis via the miR-143/TLR2 axis to promote doxorubicin-induced cardiac damage.

Doxorubicin (DOX)-mediated cardiotoxicity can impair the clinical efficacy of chemotherapy, leading to heart failure (HF). Given the importance of circRNAs and miRNAs in HF, this paper intended to delineate the mechanism of the circular RNA 0006332 (circ -0,006,332)/microRNA (miR)-143/Toll-like receptor 2 (TLR2) axis in doxorubicin (DOX)-induced HF. The binding of miR-143 to circ -0,006,332 and TLR2 was assessed with the dual-luciferase assay, and the binding between miR-143 and circ -0,006,332 was determined with FISH, RIP, and RNA pull-down assays. miR-143 and/or circ -0,006,332 were overexpressed in rats and cardiomyocytes, followed by DOX treatment. In cardiomyocytes, miR-143 and TLR2 expression, cell viability, LDH release, ATP contents, and levels of IL-1ß, IL-18, TNF-α, and pyroptosis-related molecules were examined. In rats, cardiac function, serum levels of cardiac enzymes, apoptosis, myocardial fibrosis, and levels of IL-1ß, IL-18, TNF-α, TLR2, and pyroptosis-related molecules were detected. miR-143 diminished TLR2 expression by binding to TLR2, and circ -0,006,332 bound to miR-143 to downregulate miR-143 expression. miR-143 expression was reduced and TLR2 expression was augmented in DOX-induced cardiomyocytes. miR-143 inhibited DOX-induced cytotoxicity by suppressing pyroptosis in H9C2 cardiomyocytes. In DOX-induced rats, miR-143 reduced cardiac dysfunction, myocardial apoptosis, myocardial fibrosis, TLR2 levels, and pyroptosis. Furthermore, overexpression of circ -0,006,332 blocked these effects of miR-143 on DOX-induced cardiomyocytes and rats. Circ -0,006,332 stimulates cardiomyocyte pyroptosis by downregulating miR-143 and upregulating TLR2, thus promoting DOX-induced cardiac injury.

Risk of anthracycline-induced cardiac dysfunction in adolescent and young adult (AYA) cancer survivors: role of genetic susceptibility loci.

There is a known genetic susceptibility to anthracycline-induced cardiac dysfunction in childhood cancer survivors, but this has not been adequately shown in adolescent and young adult (AYA) patients. Our aim was to determine if the previously identified variants associated with cardiac dysfunction in childhood cancer patients affect AYA cancer patients similarly. Forty-five variants were selected for analysis in 253 AYAs previously treated with anthracyclines. We identified four variants that were associated with cardiac dysfunction: SLC10A2:rs7319981 (p = 0.017), SLC22A17:rs4982753 (p = 0.019), HAS3:rs2232228 (p = 0.023), and RARG:rs2229774 (p = 0.050). HAS3:rs2232228 and SLC10A2:rs7319981 displayed significant effects in our AYA cancer survivor population that were in the opposite direction than that reported in childhood cancer survivors. Genetic variants in the host genes were further analyzed for additional associations with cardiotoxicity in AYA cancer survivors. The host genes were then evaluated in a panel of induced pluripotent stem cell-derived cardiomyocytes to assess changes in levels of expression when treated with doxorubicin. Significant upregulation of HAS3 and SLC22A17 expression was observed (p < 0.05), with non-significant anthracycline-responsivity observed for RARG. Our study demonstrates that there is a genetic influence on cardiac dysfunction in AYA cancer patients, but there may be a difference in the role of genetics between childhood and AYA cancer survivors.

PICALM Regulating the Generation of Amyloid ß-Peptide to Promote Anthracycline-Induced Cardiotoxicity.

Anthracyclines are chemotherapeutic drugs used to treat solid and hematologic malignancies. However, life-threatening cardiotoxicity, with cardiac dilation and heart failure, is a drawback. A combination of in vivo for single cell/nucleus RNA sequencing and in vitro approaches is used to elucidate the underlying mechanism. Genetic depletion and pharmacological blocking peptides on phosphatidylinositol binding clathrin assembly (PICALM) are used to evaluate the role of PICALM in doxorubicin-induced cardiotoxicity in vivo. Human heart tissue samples are used for verification. Patients with end-stage heart failure and chemotherapy-induced cardiotoxicity have thinner cell membranes compared to healthy controls do. Using the doxorubicin-induced cardiotoxicity mice model, it is possible to replicate the corresponding phenotype in patients. Cellular changes in doxorubicin-induced cardiotoxicity in mice, especially in cardiomyocytes, are identified using single cell/nucleus RNA sequencing. Picalm expression is upregulated only in cardiomyocytes with doxorubicin-induced cardiotoxicity. Amyloid ß-peptide production is also increased after doxorubicin treatment, which leads to a greater increase in the membrane permeability of cardiomyocytes. Genetic depletion and pharmacological blocking peptides on Picalm reduce the generation of amyloid ß-peptide. This alleviates the doxorubicin-induced cardiotoxicity in vitro and in vivo. In human heart tissue samples of patients with chemotherapy-induced cardiotoxicity, PICALM, and amyloid ß-peptide are elevated as well.

Computational approaches identify a transcriptomic fingerprint of drug-induced structural cardiotoxicity.

Structural cardiotoxicity (SCT) presents a high-impact risk that is poorly tolerated in drug discovery unless significant benefit is anticipated. Therefore, we aimed to improve the mechanistic understanding of SCT. First, we combined machine learning methods with a modified calcium transient assay in human-induced pluripotent stem cell-derived cardiomyocytes to identify nine parameters that could predict SCT. Next, we applied transcriptomic profiling to human cardiac microtissues exposed to structural and non-structural cardiotoxins. Fifty-two genes expressed across the three main cell types in the heart (cardiomyocytes, endothelial cells, and fibroblasts) were prioritised in differential expression and network clustering analyses and could be linked to known mechanisms of SCT. This transcriptomic fingerprint may prove useful for generating strategies to mitigate SCT risk in early drug discovery.

Cardiomyocyte-specific Tbk1 deletion aggravated chronic doxorubicin cardiotoxicity via inhibition of mitophagy.

Doxorubicin (Dox) use is limited by Dox-induced cardiotoxicity. TANK-blinding kinase 1 (TBK1) is an important kinase involved in the regulation of mitophagy, but the role of TBK1 in cardiomyocytes in chronic Dox-induced cardiomyopathy remains unclear. Cardiomyocyte-specific Tbk1 knockout (Tbk1CKO) mice received Dox (6 mg/kg, injected intraperitoneally) once a week for 4 times, and cardiac assessment was performed 4 weeks after the final Dox injection. Adenoviruses encoding Tbk1 or containing shRNA targeting Tbk1, or a TBK1 phosphorylation inhibitor were used for overexpression or knockdown of Tbk1, or inhibit phosphorylation of TBK1 in isolated primary cardiomyocytes. Our results revealed that moderate Dox challenge decreased TBK1 phosphorylation (with no effect on TBK1 protein levels), resulting in compromised myocardial function, obvious mortality and overt interstitial fibrosis, and the effects were accentuated by Tbk1 deletion. Dox provoked mitochondrial membrane potential collapse and oxidative stress, the effects of which were exacerbated and mitigated by Tbk1 knockdown, specific inhibition of phosphorylation and overexpression, respectively. However, Tbk1 （Ser172A） overexpression did not alleviate these effects. Further scrutiny revealed that TBK1 exerted protective effects on mitochondria via SQSTM1/P62-mediated mitophagy. Tbk1 overexpression mediated cardioprotective effects on Dox-induced cardiotoxicity were cancelled off by Sqstm1/P62 knockdown. Moreover, TBK1-mitophagy-mitochondria cascade was confirmed in heart tissues from dilated cardiomyopathy patients. Taken together, our findings denoted a pivotal role of TBK1 in Dox-induced mitochondrial injury and cardiotoxicity possibly through its phosphorylation and SQSTM1/P62-mediated mitophagy.

HER2/neu 655 polymorphism, trastuzumab-induced cardiotoxicity, and survival in HER2-positive breast cancer patients.

PURPOSE: HER2 overexpression in breast cancer correlates with poor outcomes. The incorporation of Trastuzumab into the treatment regimen has notably improved patient prognoses. However, cardiotoxicity emerges in approximately 20% of patients treated with the drug. This study aims to investigate the association between the HER2 655 A > G polymorphism, Trastuzumab-induced cardiotoxicity, and patient survival. METHODS: The study involved 88 patients treated with Trastuzumab. Cardiotoxicity, defined as a reduction in left ventricular ejection fraction (LVEF) from baseline or the emergence of clinical signs of congestive heart failure, was identified during treatment follow-up. Genotyping of HER2 655 A > G employed TaqMan SNP technology. RESULTS: Genotype frequencies of HER2/neu 655 (53 AA, 32 AG, and 3 GG) were consistent with Hardy-Weinberg equilibrium. No significant differences were observed in mean baseline LVEF between patients who developed cardiotoxicity and those who did not. Within these groups, neither AA nor AG genotypes showed an association with changes in mean baseline or reduced LVEF levels. Logistic regression analysis, adjusted for hormonal status and anthracycline treatment, revealed that AG genotype carriers face a significantly higher risk of cardiotoxicity compared to AA carriers (OR = 4.42; p = 0.037). No association was found between the HER2/neu 655 A > G polymorphism and disease-free or overall survival, regardless of whether the data was adjusted for stage or not. CONCLUSION: HER2 655 A > G polymorphism is significantly linked to an increased risk of Trastuzumab-induced cardiotoxicity but does not correlate with variations in disease-free survival or overall survival rates.

RNA sequencing of formalin fixed paraffin-embedded heart tissue provides transcriptomic information about chemotherapy-induced cardiotoxicity.

Gene expression of formalin-fixed paraffin-embedded (FFPE) tissue may serve for molecular studies on cardiovascular diseases. Chemotherapeutics, such as doxorubicin (DOX) may cause heart injury, but the mechanisms of these side effects of DOX are not well understood. This study aimed to investigate whether DOX-induced gene expression in archival FFPE heart tissue in experimental rats would correlate with the gene expression in fresh-frozen heart tissue by applying RNA sequencing technology. The results showed RNA from FFPE samples was degraded, resulting in a lower number of uniquely mapped reads. However, DOX-induced differentially expressed genes in FFPE were related to molecular mechanisms of DOX-induced cardiotoxicity, such as inflammation, calcium binding, endothelial dysfunction, senescence, and cardiac hypertrophy signaling. Our data suggest that, despite the limitations, RNA sequencing of archival FFPE heart tissue supports utilizing FFPE tissues from retrospective studies on cardiovascular disorders, including DOX-induced cardiotoxicity.

What Powers Trastuzumab's Cardiotoxicity? Decoding Mitochondrial-Related Gene Expression Through Integrative Review and Meta-Analysis in Cardiomyocytes.

Trastuzumab is a monoclonal antibody used in oncotherapy for HER2-positive tumors. However, as an adverse effect, trastuzumab elevates the risk of heart failure, implying the involvement of energy production and mitochondrial processes. Past studies with transcriptome analysis have offered insights on pathways related to trastuzumab safety and toxicity but limited study sizes hinder conclusive findings. Therefore, we meta-analyzed mitochondria-related gene expression data in trastuzumab-treated cardiomyocytes. We searched the transcriptome databases for trastuzumab-treated cardiomyocytes in the ArrayExpress, DDBJ Omics Archive, Gene Expression Omnibus, Google Scholar, PubMed, and Web of Science repositories. A subset of 1270 genes related to mitochondrial functions (biogenesis, organization, mitophagy, and autophagy) was selected from the Kyoto Encyclopedia of Genes and Genomes and Gene Ontology Resource databases to conduct the present meta-analysis using the Metagen package (Study register at PROSPERO: CRD42021270645). Three datasets met the inclusion criteria and 1243 genes were meta-analyzed. We observed 69 upregulated genes after trastuzumab treatment which were related mainly to autophagy (28 genes) and mitochondrial organization (28 genes). We also found 37 downregulated genes which were related mainly to mitochondrial biogenesis (11 genes) and mitochondrial organization (24 genes). The present meta-analysis indicates that trastuzumab therapy causes an unbalance in mitochondrial functions, which could, in part, help explain the development of heart failure and yields a list of potential molecular targets. These findings contribute to our understanding of the molecular mechanisms underlying the cardiotoxic effects of trastuzumab and may have implications for the development of targeted therapies to mitigate such effects.

Downregulating miRNA-199a-5p exacerbates fluorouracil-induced cardiotoxicity by activating the ATF6 signaling pathway.

BACKGROUND: Fluorouracil (5-FU) might produce serious cardiac toxic reactions. miRNA-199a-5p is a miRNA primarily expressed in myocardial cells and has a protective effect on vascular endothelium. Under hypoxia stress, the expression level of miRNA-199a-5p was significantly downregulated and is closely related to cardiovascular events such as coronary heart disease, heart failure, and hypertension. We explored whether 5-FU activates the endoplasmic reticulum stress ATF6 pathway by regulating the expression of miRNA-199a-5p in cardiac toxicity. METHODS: This project established a model of primary cardiomyocytes derived from neonatal rats and treated them with 5-FU in vitro. The expression of miRNA-199a-5p and its regulation were explored in vitro and in vivo. RESULTS: 5-FU decreases the expression of miRNA-199a-5p in cardiomyocytes, activates the endoplasmic reticulum stress ATF6 pathway, and increases the expression of GRP78 and ATF6, affecting the function of cardiomyocytes, and induces cardiac toxicity. The rescue assay further confirmed that miRNA-199a-5p supplementation can reduce the cardiotoxicity caused by 5-FU, and its protective effect on cardiomyocytes depends on the downregulation of the endoplasmic reticulum ATF6 signaling pathway. CONCLUSIONS: 5-FU can down-regulate expression of miRNA-199a-5p, then activate the endoplasmic reticulum stress ATF6 pathway, increase the expression of GRP78 and ATF6, affect the function of cardiomyocytes, and induce cardiac toxicity.

Identification of ADME genes polymorphic variants linked to trastuzumab-induced cardiotoxicity in breast cancer patients: Case series of mono-institutional experience.

BACKGROUND: Long-term survival induced by anticancer treatments discloses emerging frailty among breast cancer (BC) survivors. Trastuzumab-induced cardiotoxicity (TIC) is reported in at least 5% of HER2+BC patients. However, TIC mechanism remains unclear and predictive genetic biomarkers are still lacking. Interaction between systemic inflammation, cytokine release and ADME genes in cancer patients might contribute to explain mechanisms underlying individual susceptibility to TIC and drug response variability. We present a single institution case series to investigate the potential role of genetic variants in ADME genes in HER2+BC patients TIC experienced. METHODS: We selected data related to 40 HER2+ BC patients undergone to DMET genotyping of ADME constitutive variant profiling, with the aim to prospectively explore their potential role in developing TIC. Only 3 patients ("case series"), who experienced TIC, were compared to 37 "control group" matched patients cardiotoxicity-sparing. All patients underwent to left ventricular ejection fraction (LVEF) evaluation at diagnosis and during anti-HER2 therapy. Each single probe was clustered to detect SNPs related to cardiotoxicity. RESULTS: In this retrospective analysis, our 3 cases were homogeneous in terms of clinical-pathological characteristics, trastuzumab-based treatment and LVEF decline. We identified 9 polymorphic variants in 8 ADME genes (UGT1A1, UGT1A6, UGT1A7, UGT2B15, SLC22A1, CYP3A5, ABCC4, CYP2D6) potentially associated with TIC. CONCLUSION: Real-world TIC incidence is higher compared to randomized clinical trials and biomarkers with potential predictive value aren't available. Our preliminary data, as proof of concept, could suggest a predictive role of pharmacogenomic approach in the identification of cardiotoxicity risk biomarkers for anti-HER2 treatment.

Anthracyclines induce cardiotoxicity through a shared gene expression response signature.

TOP2 inhibitors (TOP2i) are effective drugs for breast cancer treatment. However, they can cause cardiotoxicity in some women. The most widely used TOP2i include anthracyclines (AC) Doxorubicin (DOX), Daunorubicin (DNR), Epirubicin (EPI), and the anthraquinone Mitoxantrone (MTX). It is unclear whether women would experience the same adverse effects from all drugs in this class, or if specific drugs would be preferable for certain individuals based on their cardiotoxicity risk profile. To investigate this, we studied the effects of treatment of DOX, DNR, EPI, MTX, and an unrelated monoclonal antibody Trastuzumab (TRZ) on iPSC-derived cardiomyocytes (iPSC-CMs) from six healthy females. All TOP2i induce cell death at concentrations observed in cancer patient serum, while TRZ does not. A sub-lethal dose of all TOP2i induces limited cellular stress but affects calcium handling, a function critical for cardiomyocyte contraction. TOP2i induce thousands of gene expression changes over time, giving rise to four distinct gene expression response signatures, denoted as TOP2i early-acute, early-sustained, and late response genes, and non-response genes. There is no drug- or AC-specific signature. TOP2i early response genes are enriched in chromatin regulators, which mediate AC sensitivity across breast cancer patients. However, there is increased transcriptional variability between individuals following AC treatments. To investigate potential genetic effects on response variability, we first identified a reported set of expression quantitative trait loci (eQTLs) uncovered following DOX treatment in iPSC-CMs. Indeed, DOX response eQTLs are enriched in genes that respond to all TOP2i. Next, we identified 38 genes in loci associated with AC toxicity by GWAS or TWAS. Two thirds of the genes that respond to at least one TOP2i, respond to all ACs with the same direction of effect. Our data demonstrate that TOP2i induce thousands of shared gene expression changes in cardiomyocytes, including genes near SNPs associated with inter-individual variation in response to DOX treatment and AC-induced cardiotoxicity.

Knockdown of NR4A1 alleviates doxorubicin-induced cardiotoxicity through inhibiting the activation of the NLRP3 inflammasome.

Doxorubicin (DOX) is a widely used antitumor drug, but its clinical applicability is hampered by the unfortunate side effect of DOX-induced cardiotoxicity (DIC). In our current study, we retrieved three high-throughput sequencing datasets related to DIC from the Gene Expression Omnibus (GEO) datasets. We conducted differential analysis using R (DESeq2) to pinpoint differentially expressed genes (DEGs, and identified 11 genes that were consistently altered in both the control and DOX-treated groups. Notably, our Random Forest analysis of these three GEO datasets highlighted the significance of nuclear receptor subfamily 4 group A member 1 (NR4A1) in the context of DIC. The DOX-induced mouse model and cell model were used for the in vivo and in vitro studies to reveal the role of NR4A1 in DIC. We found that silencing NR4A1 by adeno-associated virus serotype 9 (AAV9) contained shRNA in vivo alleviated the DOX-induced cardiac dysfunction, cardiomyocyte injury and fibrosis. Mechanistically, we found NR4A1 silencing was able to inhibit DOX-induced the cleavage of NLRP3, IL-1ß and GSDMD in vivo. Further in vitro studies have shown that inhibition of NR4A1 suppressed DOX-induced cytotoxicity and oxidative stress through the same molecular mechanism. We prove that NR4A1 plays a critical role in DOX-induced cardiotoxicity by inducing pyroptosis via activation of the NLRP3 inflammasome, and it might be a promising therapeutic target for DIC.

The Role of RARG rs2229774, SLC28A3 rs7853758, and UGT1A6*4 rs17863783 Single-nucleotide Polymorphisms in the Doxorubicin-induced Cardiotoxicity in Solid Childhood Tumors.

BACKGROUND: The objective of our study was to determine the role of retinoic acid receptor gamma (RARG) rs2229774, SLC28A3 rs7853758, and UGT1A6*4 rs17863783 single-nucleotide polymorphisms in identifying the risk of doxorubicin-induced cardiotoxicity in pediatric solid tumors. METHODS: A total of 60 pediatric patients who had completed their treatment at least 2 years ago and 50 healthy children matched for age and sex were included in the study. All patients were evaluated for cardiotoxicity by echocardiography. The blood samples were analyzed for RARG rs2229774, SLC28A3 rs7853758, and UGT1A6*4 rs17863783 polymorphisms. Demographic characteristics, echocardiographic parameters, and genetic results of both groups were evaluated. RESULTS: In our study, the RARG rs2229774 AA genotype was associated with cardiotoxicity ( P =0.017). The SLC28A3 rs7853758 AA+GA genotype was detected more frequently in patients who did not develop cardiotoxicity ( P <0.023). Furthermore, the frequency of the SLC28A3 rs7853758 A allele was significantly lower in the cardiotoxicity group ( P <0.025). CONCLUSIONS: This is the first study in the Turkish population to investigate the correlation between the cardiotoxicity risk and 3 marker genes, which are recommended in the pharmacogenetic guideline for risk assessment in pediatric doxorubicin patients. The gene polymorphism that we investigated in this study was useful for the early prediction of cardiotoxicity risk.