Trastuzumab cardiotoxicity: from clinical trials to experimental studies

Pharmacokinetics of trastuzumab and its efficacy and safety in HER2-positive cancer patients

Trastuzumab is a potent targeted therapy drug for HER2-positive cancer patients. A comprehensive understanding of trastuzumab's mechanism of action, pharmacokinetic (PK) parameters, and steady-state exposure in different treatment regimens and administration routes is essential for a thorough evaluation of the drug's safety and effectiveness. Due to the distinctive pharmacokinetics, indications, and administration methods of trastuzumab, this understanding becomes crucial. Drug exposure can be assessed by measuring trastuzumab's peak concentration, trough concentration, or area under the curve through assays like enzyme-linked immunosorbent assay (ELISA) or liquid chromatography-tandem mass spectrometry (LC-MS/MS). The dose-response (D-R) and exposure-response (E-R) relationships establish the correlation between drug dosage/exposure and the therapeutic effect and safety. Additionally, various covariates such as body weight, aspartate transaminase, and albumin levels can influence drug exposure. This review provides a comprehensive overview of trastuzumab's mechanism of action, data on steady-state concentration and PK parameters under multiple administration routes and indications, discussions on factors influencing PK parameters, and evaluations of the effectiveness and safety of E-R and D-R in diverse HER2-positive cancer patients.

ErbB2-NOTCH1 axis controls autophagy in cardiac cells

Although the epidermal growth factor receptor 2 (ErbB2) and Notch1 signaling pathways have both significant roles in regulating cardiac biology, their interplay in the heart remains poorly investigated. Here, we present evidence of a crosstalk between ErbB2 and Notch1 in cardiac cells, with effects on autophagy and proliferation. Overexpression of ErbB2 in H9c2 cardiomyoblasts induced Notch1 activation in a post-transcriptional, p38-dependent manner, while ErbB2 inhibition with the specific inhibitor, lapatinib, reduced Notch1 activation. Moreover, incubation of H9c2 cells with lapatinib resulted in stalled autophagic flux and decreased proliferation, consistent with the established cardiotoxicity of this and other ErbB2-targeting drugs. Confirming the findings in H9c2 cells, exposure of primary neonatal mouse cardiomyocytes to exogenous neuregulin-1, which engages ErbB2, stimulated proliferation, and this effect was abrogated by concomitant inhibition of the enzyme responsible for Notch1 activation. Furthermore, the hearts of transgenic mice specifically overexpressing ErbB2 in cardiomyocytes had increased levels of active Notch1 and of Notch-related genes. These data expand the knowledge of ErbB2 and Notch1 functions in the heart and may allow better understanding the mechanisms of the cardiotoxicity of ErbB2-targeting cancer treatments.

Possible protective effect of rosuvastatin in chemotherapy-induced cardiotoxicity in HER2 positive breast cancer patients: a randomized controlled trial

Cardiotoxicity is a side effect of chemotherapy in human epidermal growth factor receptor 2 (HER2) positive breast cancer patients receiving both anthracyclines and trastuzumab. We looked for a possible protective effect of rosuvastatin against chemotherapy-induced cardiotoxicity. Methods: 50 newly diagnosed HER2 positive breast cancer patients were randomly allocated into two groups: 25patients in each. Group 1(control group) received doxorubicin for 4 cycles (3 months) followed by trastuzumab adjuvant therapy. Group 2 (treatment group) received doxorubicin for 4 cycles (3 months) followed by trastuzumab adjuvant therapy and 20 mg of oral rosuvastatin 24 h before the first cycle of chemotherapy and once daily for the rest of the follow-up period (6 months). Transthoracic echocardiography was done, and blood samples were collected for patients 24 h before the initiation of therapy, after 3 months and after 6 months to assess serum levels of high sensitivity cardiac troponin I (hs-cTnI), Myeloperoxidase (MPO), Interleukin-6 (IL-6) and Alanine aminotransferase (ALT). The study was retrospectively registered in Clinical Trials.gov in April 2022. Its ID is NCT05338723. Compared to control group, Rosuvastatin-treated group had a significantly lower decline in LVEF after 3 months and after 6 months. They had significantly lower Hs-cTnI and IL-6 after 3 months and after 6 months, and significantly lower MPO after 6 months. Four patients in control group experienced cardiotoxicity while no one in rosuvastatin-treated group. Rosuvastatin attenuated cardiotoxicity, so it is a promising protective agent against chemotherapy-induced cardiotoxicity.

Immune checkpoints in cardiac physiology and pathology: therapeutic targets for heart failure

Immune checkpoint molecules are physiological regulators of the adaptive immune response. Immune checkpoint inhibitors (ICIs), such as monoclonal antibodies targeting programmed cell death protein 1 or cytotoxic T lymphocyte-associated protein 4, have revolutionized cancer treatment and their clinical use is increasing. However, ICIs can cause various immune-related adverse events, including acute and chronic cardiotoxicity. Of these cardiovascular complications, ICI-induced acute fulminant myocarditis is the most studied, although emerging clinical and preclinical data are uncovering the importance of other ICI-related chronic cardiovascular complications, such as accelerated atherosclerosis and non-myocarditis-related heart failure. These complications could be more difficult to diagnose, given that they might only be present alongside other comorbidities. The occurrence of these complications suggests a potential role of immune checkpoint molecules in maintaining cardiovascular homeostasis, and disruption of physiological immune checkpoint signalling might thus lead to cardiac pathologies, including heart failure. Although inflammation is a long-known contributor to the development of heart failure, the therapeutic targeting of pro-inflammatory pathways has not been successful thus far. The increasingly recognized role of immune checkpoint molecules in the failing heart highlights their potential use as immunotherapeutic targets for heart failure. In this Review, we summarize the available data on ICI-induced cardiac dysfunction and heart failure, and discuss how immune checkpoint signalling is altered in the failing heart. Furthermore, we describe how pharmacological targeting of immune checkpoints could be used to treat heart failure.

Role of Early Left Atrial Functional Decline in Predicting Cardiotoxicity in HER2 Positive Breast Cancer Patients Treated With Trastuzumab

Trastuzumab is widely used in HER2 breast cancer. However, it may cause left ventricular (LV) dysfunction. A decrease in LV global longitudinal strain (GLS) has been previously demonstrated to be a good predictor of subsequent cancer therapy related dysfunction (CTRCD). Left atrial morphological remodeling during Trastuzumab therapy has also been shown. The aim of this study is exploring the relationship between early changes in left atrial function and the development of Trastuzumab-induced cardiotoxicity. Consecutive patients with diagnosis of HER2+non-metastatic breast cancer treated with Trastuzumab were prospectively enrolled. A clinical, conventional, and advanced echocardiographic assessment was performed at baseline and every three months, until a one-year follow-up was reached. One-hundred-sixteen patients completed the 12 months follow-up, 10 (9%) cases of CTRCD were observed, all after the sixth month. GLS and LVEF significantly decreased in the CTRCD group at 6 months of follow-up, with an earlier (3 months) significant worsening in left atrial morpho-functional parameters. Systolic blood pressure, early peak atrial longitudinal strain (PALS), peak atrial contraction (PACS) and left atrial volume (LAVI) changes resulted independent predictors of CTRCD at multivariable logistic regression analysis. Moreover, early changes in PALS and PACS resulted good predictors of CTRCD development (AUC 0.85; p = 0.008, p < 0.001 and 0.77; p = 0.008, respectively). This prospective study emphasizes that the decline in PALS and PACS among trastuzumab-treated patients could possibly increase the accuracy in identifying future CTRCD in non-metastatic HER2 breast cancer cases, adding predictive value to conventional echocardiographic assessment.

Incidence of chemotherapy-related cardiac dysfunction in cancer patients

BACKGROUND

Cancer patients are increasingly affected by chemotherapy-related cardiac dysfunction. The reported incidence of this condition vary significantly across different studies.

HYPOTHESIS

A better comprehensive understanding of chemotherapy-related cardiac dysfunction incidence in cancer patients is imperative. Therefore, we performed a meta-analysis to establish the overall incidence of chemotherapy-related cardiac dysfunction in cancer patients.

METHODS

We searched articles in PubMed and EMBASE from database inception to May 1, 2023. Studies that reported the incidence of chemotherapy-related cardiac dysfunction in cancer patients were included.

RESULTS

A total of 53 studies involving 35 651 individuals were finally included in the meta-analysis. The overall pooled incidence of chemotherapy-related cardiac dysfunction in cancer patients was 63.21 per 1000 person-years (95% CI: 57.28-69.14). The chemotherapy-related cardiac dysfunction incidence increased steeply within half a year of cancer chemotherapy. Also, the trend of chemotherapy-related cardiac dysfunction incidence appeared to have plateaued after a longer duration of follow-up. In addition, chemotherapy-related cardiac dysfunction incidence rates are significantly higher among patients with age ≥50 years versus patients with age <50 years (99.96 vs. 34.48 per 1000 person-years). The incidence rate of cardiac dysfunction was higher among breast cancer patients (72.97 per 1000 person-years), leukemia patients (65.21 per 1000 person-years), and lymphoma patients (55.43 per 1000 person-years).

CONCLUSION

Our meta-analysis unveiled a definitive overall incidence rate of chemotherapy-related cardiac dysfunction in cancer patients. In addition, it was found that the risk of developing this condition escalates within the initial 6 months postchemotherapy, subsequently tapering off to become statistically insignificant after a duration of 6 years.

Impact of a Cancer History on Cardiovascular Events Among Patients With Myocardial Infarction Who Received Revascularization

BACKGROUND

It remains controversial whether a cancer history increases the risk of cardiovascular (CV) events among patients with myocardial infarction (MI) who undergo revascularization.

METHODS AND RESULTS

Patients who were confirmed as type 1 acute MI (AMI) by coronary angiography were retrospectively analyzed. Patients who died in hospital or those not undergoing revascularization were excluded. Patients with a cancer history were compared with those without it. A cancer history was examined in the in-hospital cancer registry. The primary outcome was a composite of cardiac death, recurrent type 1 MI, post-discharge coronary revascularization, heart failure hospitalization, and stroke. Among 551 AMI patients, 55 had a cancer history (cancer group) and 496 did not (non-cancer group). Cox proportional hazards model revealed that the risk of composite endpoint was significantly higher in the cancer group than in the non-cancer group (adjusted hazard ratio [HR]: 1.78; 95% confidence interval [CI]: 1.13-2.82). Among the cancer group, patients who were diagnosed as AMI within 6 months after the cancer diagnosis had a higher risk of the composite endpoint than those who were diagnosed as AMI 6 months or later after the cancer diagnosis (adjusted HR: 5.43; 95% CI: 1.55-19.07).

CONCLUSIONS

A cancer history increased the risk of CV events after discharge among AMI patients after revascularization.

A new perspective in the prevention and treatment of antitumor therapy-related cardiotoxicity: Intestinal microecology

The continuous development of antitumor therapy has significantly reduced the mortality of patients with malignancies. However, the antitumor-related cardiotoxicity has become the leading cause of long-term mortality in patients with malignancies. Besides, the pathogenesis of antitumor-related cardiotoxicity is still unclear, and practical means of prevention and treatment are lacking in clinical practice. Therefore, the major challenge is how to combat the cardiotoxicity of antitumor therapy effectively. More and more studies have shown that antitumor therapy kills tumor cells while causing damage to sensitive tissues such as the intestinal mucosa, leading to the increased permeability of the intestine and the dysbiosis of intestinal microecology. In addition, the dysbiosis of intestinal microecology contributes to the development and progression of cardiovascular diseases through multiple pathways. Thus, the dysbiosis of intestinal microecology may be a potential mechanism and target for antitumor-related cardiotoxicity. We summarized the characteristics of intestinal microecology disorders induced by antitumor therapy and the association between intestinal microecological dysbiosis and CVD. And on this basis, we hypothesized the potential mechanisms of intestinal microecology mediating the occurrence of antitumor-related cardiotoxicity. Then we reviewed the previous studies targeting intestinal microecology against antitumor-associated cardiotoxicity, aiming to provide a reference for future studies on the occurrence and prevention of antitumor-related cardiotoxicity by intestinal microecology.

Osthole protects H9c2 cardiomyocytes against trastuzumab-induced damage by enhancing autophagy through the p38MAPK/mTOR signaling pathway

Trastuzumab (TRZ) is a novel targeted anti-tumor agent that significantly improve the survival of patients with human epidermal growth factor receptor (HER2) positive breast cancer. However, its clinical application is limited due to the side effects of cardiotoxicity. Osthole (OST), a coumarin derivative isolated from Cnidium monnieri (L.) Cusson, has previously demonstrated cardioprotective effects. The aim of this study was to observe the protective effect of OST on TRZ-induced cardiomyocytes damage and to explore its potential mechanism. The results showed that OST pretreatment could significantly inhibit TRZ-induced cardiomyocytes damage, markedly increase the ratio of LC3II/I and Beclin-1 protein expression, and reduce the protein expression of p62. OST pretreatment significantly attenuated oxidative stress and apoptosis induced by TRZ, as evidenced by reducing intracellular ROS level, the Bax/Bcl-2 ratio, and Caspase-3 protein expression. Additionally, OST markedly increased the phosphorylation level of p38MAPK and decreased the mTOR phosphorylation level. However, the effects of OST on enhancing autophagy, reducing oxidative stress, apoptosis, and the phosphorylation level of mTOR were reversed after the addition of 3-MA or SB203580. Molecular docking results indicated that OST exerted a good binding ability with the p38MAPK protein. Our findings suggested that OST could protect TRZ-induced cardiomyocytes damage by enhancing autophagy via the p38MAPK/mTOR signaling pathway.

Preventing broken hearts in women with breast cancer: a concise review on chemotherapy-mediated cardiotoxicity

Cancer and cardiovascular disease are the leading causes of death for Canadian women. One in eight Canadian women will receive the life-changing diagnosis of breast cancer (BC) in their lifetime, with 1 in 34 dying from the disease. Although doxorubicin (DOX) and trastuzumab (TRZ) have significantly improved survival in women diagnosed with human epidermal growth factor receptor 2 (HER2)-positive BC, approximately one in four women who receive this treatment are at risk of developing chemotherapy-induced cardiotoxicity. Cardiotoxicity is defined as a decline in left ventricular ejection fraction (LVEF) of >10% to an absolute value of <53%. Current guidelines recommend the serial monitoring of LVEF in this patient population using non-invasive cardiac imaging modalities including transthoracic echocardiography or multi-gated acquisition scan; however, this will only allow for the detection of established cardiotoxicity. Recent studies have demonstrated that a reduction in global longitudinal strain by speckle tracking echocardiography can identify pre-clinical systolic dysfunction prior to a decline in overall LVEF. Implementation of early detection techniques would allow for the prompt initiation of cardioprotective strategies. In addition to the early detection of chemotherapy-mediated cardiotoxicity, the prophylactic use of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, β-blockers, statins, exercise, and nutraceutical therapies have been studied in the setting of cardio-oncology.

Multiomics Analysis Provides Novel Pathways Related to Progression of Heart Failure

BACKGROUND

Despite major advances in pharmacological treatment for patients with heart failure, residual mortality remains high. This suggests that important pathways are not yet targeted by current heart failure therapies.

OBJECTIVES

We sought integration of genetic, transcriptomic, and proteomic data in a large cohort of patients with heart failure to detect major pathways related to progression of heart failure leading to death.

METHODS

We used machine learning methodology based on stacked generalization framework and gradient boosting algorithms, using 54 clinical phenotypes, 403 circulating plasma proteins, 36,046 transcript expression levels in whole blood, and 6 million genomic markers to model all-cause mortality in 2,516 patients with heart failure from the BIOSTAT-CHF (Systems BIOlogy Study to TAilored Treatment in Chronic Heart Failure) study. Results were validated in an independent cohort of 1,738 patients.

RESULTS

The mean age of the patients was 70 years (Q1-Q3: 61-78 years), 27% were female, median N-terminal pro-B-type natriuretic peptide was 4,275 ng/L (Q1-Q3: 2,360-8,486 ng/L), and 7% had heart failure with preserved ejection fraction. During a median follow-up of 21 months, 657 (26%) of patients died. The 4 major pathways with a significant association to all-cause mortality were: 1) the PI3K/Akt pathway; 2) the MAPK pathway; 3) the Ras signaling pathway; and 4) epidermal growth factor receptor tyrosine kinase inhibitor resistance. Results were validated in an independent cohort of 1,738 patients.

CONCLUSIONS

A systems biology approach integrating genomic, transcriptomic, and proteomic data identified 4 major pathways related to mortality. These pathways are related to decreased activation of the cardioprotective ERBB2 receptor, which can be modified by neuregulin.

The Value of Neoadjuvant Anthracycline-Based Regimens for HER2-Positive Breast Cancer: A Systematic Review and Meta-analysis Including 1366 Patients

Background

The standard recommendation for neoadjuvant therapy for human epidermal growth factor receptor-2 (HER2)-positive breast cancer patients is trastuzumab in combination with chemotherapy, but there is no current standard recommendation for appropriate chemotherapy regimens. This meta-analysis evaluated the efficacy and cardiac safety of the concurrent use of anti-HER2 targeted drugs and anthracycline-based neoadjuvant chemotherapy (NAC) for HER2-positive breast cancers.

Methods

The pooled odds ratio (OR) rate for pathologic complete response (pCR), the pooled hazard ratio (HR) of overall survival (OS), and the left ventricular ejection fraction (LVEF) decline events were all calculated. Differences in efficacy, prognosis, and cardiac safety were compared between patients receiving an anthracycline-containing regimen (AB) and those treated with non-anthracycline-based (nAB) NAC.

Results

A total of 1366 patients in 4 prospective and 3 retrospective studies were included in the meta-analysis. The pooled OR for pCR rate was 0.73 with a 95% confidence interval (CI) of 0.43 to 1.24 (P = .246). Subgroup analysis of low tumor burden cases showed no improvement in pCR rate for patients in the AB group compared with nAB, with the pooled OR rate being 0.73 with a 95% CI of 0.37 to 1.44 (P= .357). The 3-year OS rate was 95.63% and 95.54% in the AB and nAB groups, respectively, with no statistical difference (P= .157). There was a significant increase in the rate of LVEF decline of 19.07% in the AB group compared with 13.33% for the nAB group, with an HR of 1.62 and a 95% CI of 1.11 to 2.36 (P = .013).

Conclusions

The addition of anthracyclines did not improve pCR rates and survival after neoadjuvant and the increased cardiotoxicity of anthracyclines further limited their application. This study showed that it was feasible to use anti-HER2 drugs without anthracyclines in neoadjuvant therapy for HER2-positive breast cancer patients.

Mitochondrial dysfunction at the crossroad of cardiovascular diseases and cancer

A large body of evidence indicates the existence of a complex pathophysiological relationship between cardiovascular diseases and cancer. Mitochondria are crucial organelles whose optimal activity is determined by quality control systems, which regulate critical cellular events, ranging from intermediary metabolism and calcium signaling to mitochondrial dynamics, cell death and mitophagy. Emerging data indicate that impaired mitochondrial quality control drives myocardial dysfunction occurring in several heart diseases, including cardiac hypertrophy, myocardial infarction, ischaemia/reperfusion damage and metabolic cardiomyopathies. On the other hand, diverse human cancers also dysregulate mitochondrial quality control to promote their initiation and progression, suggesting that modulating mitochondrial homeostasis may represent a promising therapeutic strategy both in cardiology and oncology. In this review, first we briefly introduce the physiological mechanisms underlying the mitochondrial quality control system, and then summarize the current understanding about the impact of dysregulated mitochondrial functions in cardiovascular diseases and cancer. We also discuss key mitochondrial mechanisms underlying the increased risk of cardiovascular complications secondary to the main current anticancer strategies, highlighting the potential of strategies aimed at alleviating mitochondrial impairment-related cardiac dysfunction and tumorigenesis. It is hoped that this summary can provide novel insights into precision medicine approaches to reduce cardiovascular and cancer morbidities and mortalities.

Cardiovascular adverse effects associated with the use of anti-HER2 in breast cancer treatment

Background: Cancer represents an important public health problem with increasing incidence, prevalence, and mortality, affecting the entire Western population, especially in developed and developing countries. The use of monoclonal antibodies has revolutionized the treatment of cancer, but this treatment can cause adverse cardiovascular effects (AE). Objective: The objective of this paper is to identify and classify AE in breast cancer patients in the use of Trastuzumab in two health institutions. Methods: Retrospective study of medical records of patients with breast cancer Her 2+ submitted the therapy with trastuzumab in early and advanced stage of the disease. Review conducted in a university hospital and a private clinic, both located in Rio de Janeiro State, Brazil. Results: Cardiovascular events were late for trastuzumab, with predominance of moderate reactions. There was a predominance of dyspnea, increased blood pressure, fatigue and reduced left ventricular ejection. Conclusion: The results resemble similarities in the pattern of the institutions' reactions. Identify possible AE and know the toxicity profile of trastuzumab can contribute to a safer therapy.

Cardiotoxicity of breast cancer chemotherapy

Breast cancer is one of the leading causes of malignancy affecting women in the United States. Although many effective treatments are available, most come with notable side effects that providers and patients must take into consideration. Various classes of chemotherapeutic agents, including anthracyclines and human epidermal growth factor receptor-2 antagonists, are known to be toxic to myocardial tissue. In this review article, we discuss what is reported in the literature regarding the cardiotoxicity of these agents as well as how to monitor and prevent cardiac injury and dysfunction.

Trastuzumab-induced cardiomyopathy via ferroptosis-mediated mitochondrial dysfunction

Trastuzumab (TRZ) is a first-line chemotherapeutic agent for HER-2 (ErbB2)-positive breast cancer. Unfortunately, its clinical use is limited due to its cardiotoxicity, referred to as TRZ-induced cardiotoxicity (TIC). However, the exact molecular mechanisms underlying the development of TIC remain unclear. Iron and lipid metabolism and redox reactions participate in the development of ferroptosis. Here, we show that ferroptosis-mediated mitochondrial dysfunction is involved in TIC in vivo and in vitro. We first established TIC models with BALB/c mice or neonatal rat cardiomyocytes and confirmed cardiomyopathy with echocardiography and inhibition of cell viability with a cell counting kit-8 examination, respectively. We showed that TRZ downregulated glutathione peroxidase 4 (GPx4) and elevated lipid peroxidation by-products, 4-hydroxynonenal (4-HNE) and malondialdehyde (MDA), by inactivating the ErbB2/PI3K/AKT/Nrf2 signalling pathway. Additionally, upregulated mitochondrial 4-HNE binds to voltage-dependent anion channel 1 (VDAC1), increases VDAC1 oligomerization, and subsequently induces mitochondrial dysfunction, as evidenced by mitochondrial permeability transition pore (mPTP) opening and decreased mitochondrial membrane potential (MMP) and ATP levels. Concomitantly, TRZ affected the mitochondrial levels of GSH/GSSG and iron ions and the stability of mitoGPx4. Ferroptosis inhibitors, such as ferrostatin-1 (Fer-1) or the iron chelator deferoxamine (DFO), ameliorate TRZ-induced cardiomyopathy. Overexpression of mitoGPx4 also suppressed mitochondrial lipid peroxidation and prevented TRZ-induced ferroptosis. Our study strongly suggests that targeting ferroptosis-mediated mitochondrial dysfunction is a potential cardioprotective strategy.

Cardiotoxicities of Non-Chemotherapeutic Metastatic Breast Cancer Treatments

PURPOSE OF REVIEW

Although mortality rates have declined significantly in recent years, breast cancer remains the second most common cause of cancer death in women, with rates significantly higher among women with metastatic disease. New therapeutic agents have improved the prognosis of patients with metastatic breast cancer but raise concerns around the risk of cardiovascular disease. This review aims to discuss the oncologic treatment of the different subtypes of breast cancer along with the cardiac complications associated with each therapy.

RECENT FINDINGS

This article emphasizes human epidermal growth factor receptor targeted therapies with a focus on incidence of cardiotoxicity, reversibility, long-term outcomes, and management in high-risk patients. This review will address the use of cardiac biomarkers to monitor for toxicity, as well as the utility of cardiac imaging, including global longitudinal strain as a prognostic factor. We will also include recent findings on tyrosine kinase inhibitors, cyclin dependent kinase 4/6, and immune checkpoint inhibitors. Cardiotoxicity may lead to premature discontinuation of novel cancer therapies; optimizing cardiovascular risk factors and close monitoring for cardiotoxicity allow patients to maximize their oncologic and cardiovascular outcomes.

Diagnostic Value of Three-Dimensional Speckle Tracking Imaging Strain Parameters for Detection of Cancer Chemotherapy-Related Cardiac Dysfunction: A Meta-Analysis

BACKGROUND

Chemotherapeutic agents (e.g., anthracyclines, trastuzumab) commonly used for treating malignant tumors have been demonstrated to have cardiotoxic effects, which is associated with poor prognosis. Three-dimensional echocardiography has been used to predict cancer chemotherapy-induced cardiac dysfunction.

OBJECTIVES

Evaluation of the diagnostic performance of strain parameters, global area strain (GAS), longitudinal strain (GLS), circumferential strain (GCS), and radial strain (GRS) by meta-analysis.

METHODS

Relevant studies were searched from the Embase, PubMed, and Web of Science databases. Statistical analysis was performed using Stata 12. The summary receiver operating characteristic curve, sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and corresponding 95% confidence interval for the four strain parameters were pooled. P<0.05 was considered statistically significant.

RESULTS

Nine studies involving 650 participants were included. GAS and GLS showed significant diagnostic advantages over GCS and GRS. For GAS, the sensitivity was 0.85 (0.70, 0.93) and specificity was 0.82(0.78, 0.86) with PLR of 4.76 (3.55, 6.39) and NLR of 0.18 (0.09, 0.39) and an area under the curve (AUC) of 0.85 (0.82, 0.88). For GLS, the sensitivity was 0.81 (0.74, 0.86) and specificity was 0.81(0.68, 0.90) with PLR of 4.35(2.42, 7.80) and NLR of 0.23 (0.17, 0.33) and an AUC of 0.85 (0.82, 0.88). The GCS showed a sensitivity of 0.63 and a specificity of 0.79 with an AUC of 0.77. The GRS showed a sensitivity of 0.74 and a specificity of 0.66 with an AUC of 0.73.

CONCLUSION

3D-STI strain parameters GAS and GLS showed good performance in detecting early cardiac dysfunction in patients with tumors receiving chemotherapy.

Trastuzumab potentiates doxorubicin-induced cardiotoxicity via activating the NLRP3 inflammasome in vivo and in vitro

Trastuzumab (Tra), the first humanized monoclonal antibody that targets human epidermal growth factor receptor 2 (HER2), is commonly used alongside doxorubicin (Dox) as a combination therapy in HER2-positive breast cancer. Unfortunately, this leads to a more severe cardiotoxicity than Dox alone. NLRP3 inflammasome is known to be involved in Dox-induced cardiotoxicity and multiple cardiovascular diseases. However, whether the NLRP3 inflammasome contributes to the synergistic cardiotoxicity of Tra has not been elucidated. In this study, primary neonatal rat cardiomyocyte (PNRC), H9c2 cells and mice were treated with Dox (15 mg/kg in mice or 1μM in cardiomyocyte) or Tra (15.75 mg/kg in mice or 1μM in cardiomyocyte), or Dox combined Tra as cardiotoxicity models to investigate this question. Our results demonstrated that Tra significantly potentiated Dox-induced cardiomyocyte apoptosis and cardiac dysfunction. These were accompanied by the increased expressions of NLRP3 inflammasome components (NLRP3, ASC and cleaved caspase-1), the secretion of IL-β and the pronounced production of ROS. Inhibiting the activation of NLRP3 inflammasome by NLRP3 silencing significantly reduced cell apoptosis and ROS production in Dox combined Tra-treated PNRC. Compared with the wild type mice, the systolic dysfunction, myocardial hypertrophy, cardiomyocyte apoptosis and oxidative stress induced by Dox combined Tra were alleviated in NLRP3 gene knockout mice. Our data revealed that the co-activation of NLRP3 inflammasome by Tra promoted the inflammation, oxidative stress and cardiomyocytes apoptosis in Dox combined Tra-induced cardiotoxicity model both in vivo and in vitro. Our results suggest that NLRP3 inhibition is a promising cardioprotective strategy in Dox/Tra combination therapy.

Drug-induced oxidative stress in cancer treatments: Angel or devil?

Oxidative stress (OS), defined as redox imbalance in favor of oxidant burden, is one of the most significant biological events in cancer progression. Cancer cells generally represent a higher oxidant level, which suggests a dual therapeutic strategy by regulating redox status (i.e., pro-oxidant therapy and/or antioxidant therapy). Indeed, pro-oxidant therapy exhibits a great anti-cancer capability, attributing to a higher oxidant accumulation within cancer cells, whereas antioxidant therapy to restore redox homeostasis has been claimed to fail in several clinical practices. Targeting the redox vulnerability of cancer cells by pro-oxidants capable of generating excessive reactive oxygen species (ROS) has surfaced as an important anti-cancer strategy. However, multiple adverse effects caused by the indiscriminate attacks of uncontrolled drug-induced OS on normal tissues and the drug-tolerant capacity of some certain cancer cells greatly limit their further applications. Herein, we review several representative oxidative anti-cancer drugs and summarize their side effects on normal tissues and organs, emphasizing that seeking a balance between pro-oxidant therapy and oxidative damage is of great value in exploiting next-generation OS-based anti-cancer chemotherapeutics.

Electrocardiographic and biochemical analysis of anthracycline induced cardiotoxicity in breast cancer patients from Southern Sri Lanka

BACKGROUND

The clinical application of anthracycline chemotherapy is hindered due to the cumulative dose-dependent cardiotoxicity followed by the oxidative stress initiated during the mechanism of action of anthracyclines. Due to a lack of prevalence data regarding anthracycline-induced cardiotoxicity in Sri Lanka, this study was conducted to determine the prevalence of cardiotoxicity among breast cancer patients in Southern Sri Lanka in terms of electrocardiographic and cardiac biomarker investigations.

METHODS

A cross-sectional study with longitudinal follow-up was conducted among 196 cancer patients at the Teaching Hospital, Karapitiya, Sri Lanka to determine the incidence of acute and early-onset chronic cardiotoxicity. Data on electrocardiography and cardiac biomarkers were collected from each patient, one day before anthracycline (doxorubicin and epirubicin) chemotherapy, one day after the first dose, one day and six months after the last dose of anthracycline chemotherapy.

RESULTS

Prevalence of sub-clinical anthracycline-induced cardiotoxicity six months after the completion of anthracycline chemotherapy was significantly higher (p < 0.05) and there were strong, significant (p < 0.05) associations among echocardiography, electrocardiography measurements and cardiac biomarkers including troponin I and N-terminal pro-brain natriuretic peptides. The cumulative anthracycline dose, > 350 mg/m² was the most significant risk factor associated with the sub-clinical cardiotoxicity in breast cancer patients under study.

CONCLUSION

Since these results confirmed the unavoidable cardiotoxic changes following anthracycline chemotherapy, it is recommended to carry out long-term follow-ups in all patients who were treated with anthracycline therapy to increase their quality of life as cancer survivors.

Chemotherapy, hypothyroidism and oral dysbiosis as a novel risk factor of cardiovascular pathology development

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality in the population, as well as the economic burden of the health care system. Currently, CVDs account for more than 17.6 million deaths a year and are projected to exceed 23.6 million by 2030. Unstable atheroma, and its rupture, underlies the pathology of most cardiovascular complications, particularly acute coronary syndrome, mortality from which, compared with other CV events, remains the leading one. Despite numerous efforts by WHO, national health systems, and medical authorities, the incidence and mortality from cardiovascular events remain critically high. Thus, the search for new risk factors for the development of CV pathology looks very relevant. Our working group decided to amalgamate our research data, which reflects the study of modern risk factors from the Armenian, Russian, Georgian, and Iranian medical schools. In particular, the aspects of cardiotoxic effects of chemotherapy, hypothyroidism, and oral dysbiosis are discussed.

The mechanism and treatment of targeted anti-tumour drugs induced cardiotoxicity

As the intensive anti-tumour therapy and combination of multiple anti-tumour drugs, cardiotoxicity events caused by anti-tumour drugs have also increased significantly, and the incidence of cardiotoxicity also increased with survival time. Different types of anti-tumour drugs could cause all kinds of cardiotoxicity which increase the difficulties in treatment and even live threatening. In this review, we concentrated in the targeted anti-tumour drugs such as human epidermal growth factor receptor-2 (HER2) inhibitors, tyrosine kinase inhibitors (TKIs), immune checkpoint inhibitors (ICIs), and proteasome inhibitors (Pls). The molecular mechanism of how these drugs induce cardiotoxicity is introduced which includes several signal pathways. These drugs induced cardiotoxicity involved heart failure, hypertension, atherosis and thrombosis, QT interval prolongation, and myocarditis. Some of the cardiotoxicity could be moderate and reversible but others could have happened severely.The aim of this review is to summarise the targeted anti-tumour drugs induced cardiotoxicity and treatment strategies.

NLRP3-mediated inflammation in cardio-oncology: sterile yet harmful

Despite significant advances and the continuous development of novel, effective therapies to treat a variety of malignancies, cancer therapy-induced cardiotoxicity has been identified as a prominent cause of morbidity and mortality, closely competing with secondary malignancies. This unfortunate limitation has prompted the inception of the field of cardio-oncology with its purpose to provide the necessary knowledge and key information on mechanisms that support the use of the most efficacious cancer therapy with minimal or no interruption while paying close attention to preventing cardiovascular related morbidity and mortality. Several mechanisms that contribute to cancer therapy-induced cardiotoxicity have been proposed and studied. These mainly involve mitochondrial dysfunction and reactive oxygen species-induced oxidative stress, lysosomal damage, impaired autophagy, cell senescence, DNA damage, and sterile inflammation with the formation and activation of the NLRP3 inflammasome. In this review, we focus on describing the principal mechanisms for different classes of cancer therapies that lead to cardiotoxicity involving the NLRP3 inflammasome. We also summarize current evidence of cardio-protection with inflammasome inhibitors in the context of heart disease in general, and further highlight the potential application of this evidence for clinical translation in at risk patients for the purpose of preventing cancer therapy associated cardiovascular morbidity and mortality.

Antibody conjugates for targeted delivery of Toll-like receptor 9 agonist to the tumor tissue

Imiquimod, a Toll-like receptor 7 (TLR7) agonist is routinely used for topical administration in basal cell carcinoma and stage zero melanoma. Similarly, the TLR agonist Bacillus Calmette-Guérin is used for the local treatment of bladder cancer and clinical trials showed treatment efficacy of intratumoral injections with TLR9 agonists. However, when administered systemically, endosomal TLR agonists cause adverse responses due to broad immune activation. Hence, strategies for targeted delivery of TLR agonists to the tumor tissue are needed to enable the widespread use of endosomal TLR agonists in the context of tumor immunotherapy. One strategy for targeted delivery of TLR agonist is their conjugation to tumor antigen-specific therapeutic antibodies. Such antibody-TLR agonist conjugates act synergistically by inducing local TLR-mediated innate immune activation which complements the anti-tumor immune mechanisms induced by the therapeutic antibody. In this study, we explored different conjugation strategies for TLR9 agonists to immunoglobulin G (IgG). We evaluated biochemical conjugation of immunostimulatory CpG oligodesoxyribonucleotides (ODN) to the HER2-specific therapeutic antibody Trastuzumab with different cross-linkers comparing stochastic with site-specific conjugation. The physiochemical make-up and biological activities of the generated Trastuzumab-ODN conjugates were characterized in vitro and demonstrated that site-specific conjugation of CpG ODN is crucial for maintaining the antigen-binding capabilities of Trastuzumab. Furthermore, site-specific conjugate was effective in promoting anti-tumor immune responses in vivo in a pseudo-metastasis mouse model with engineered human HER2-transgenic tumor cells. In this in vivo model, co-delivery of Trastuzumab and CpG ODN in form of site-specific conjugates was superior to co-injection of unconjugated Trastuzumab, CpG ODN or stochastic conjugate in promoting T cell activation and expansion. Thereby, this study highlights that site-specific conjugation of CpG ODN to therapeutic antibodies targeting tumor markers is a feasible and more reliable approach for generation of conjugates which retain and combine the functional properties of the adjuvant and the antibody.

Evaluating Cardiotoxicity in Breast Cancer Patients Treated with HER2 Inhibitors: Could a Combination of Radionuclide Ventriculography and Cardiac Biomarkers Predict the Cardiac Impact?

(1) Background: The aim of our study was to determine whether monitoring cardiac function through RNV and cardiac biomarkers could predict the cardiac impact of combined therapy with trastuzumab, pertuzumab and docetaxel, which are regularly used nowadays to treat HER2-positive breast cancer. (2) Methods: This prospective monocentric study included 22 patients, diagnosed with HER2-positive breast cancer, who had their LVEFs and cardiac biomarkers evaluated both at the beginning of their treatment and after 6 months. Among all of the enrolled patients, two blood specimens were collected to assess circulating cardiac biomarkers. RNV was performed in each patient after "in vivo" radiolabeling of the erythrocytes. The obtained results were then statistically correlated. (3) Results: The average LVEF decrease between the two time points was approximately 4%. Of the five biomarkers we considered in this paper, only NT-proBNP correlated with the LVEF values obtained both in the baseline study and after 6 months of follow-up (r = -0.615 for T0 and r = -0.751 for T1, respectively). ST2/IL-33R proved statistically significant at the T1 time point (r = -0.547). (4) Conclusions: A combination of LVEF, NT-proBNP and ST2/IL-33R assessment may be useful for early detection of cardiac impairment in breast cancer patients treated with trastuzumab, pertuzumab and docetaxel.

Adverse Renal Effects of Anticancer Immunotherapy: A Review

Simple Summary

The immune system has a natural ability to work against cancer cells; however, in many cases this ability is insufficient, and cancers develop methods enabling them to escape from the supervision of immune cells. Novel therapeutic methods used in neoplastic diseases are based on encouraging immune cells to fight against cancer. In some cases, boosted by this approach, the immune system may damage not only tumor cells, but also other cells, tissues and organs in the human body. Kidney involvement, for example, is directly dangerous for patients’ health and may have an impact on human body homeostasis and the excretion of xenobiotics. However, renal function impairment in patients treated with immunotherapy is thought to be relatively rare but may be severe. Knowledge of early diagnosis and proper management are essential for physicians utilizing immunotherapy in daily clinical practice.

Abstract

Modern oncological therapy utilizes various types of immunotherapy. Immune checkpoint inhibitors (ICIs), chimeric antigen receptor T cells (CAR-T) therapy, cancer vaccines, tumor-targeting monoclonal antibodies (TT-mAbs), bispecific antibodies and cytokine therapy improve patients’ outcomes. However, stimulation of the immune system, beneficial in terms of fighting against cancer, generates the risk of harm to other cells in a patient’s body. Kidney damage belongs to the relatively rare adverse events (AEs). Best described, but still, superficially, are renal AEs in patients treated with ICIs. International guidelines issued by the European Society for Medical Oncology (ESMO) and the American Society of Clinical Oncology (ASCO) cover the management of immune-related adverse events (irAEs) during ICI therapy. There are fewer data concerning real occurrence and possible presentations of renal adverse drug reactions of other immunotherapeutic methods. This implies the need for the collection of safety data during ongoing clinical trials and in the real-life world to characterize the hazard related to the use of new immunotherapies and management of irAEs.

Inhibition of TNF-α and JNK Signaling Pathway Can Reduce Paclitaxel-Induced Apoptosis of Mouse Cardiomyocytes

Paclitaxel (PTX) is a widely used chemotherapeutic drug for treating tumors. However, studies have shown that it can cause cardiac problems such as arrhythmia, myocarditis, chronic cardiomyopathy, and heart failure. Therefore, it is essential to study the mechanism behind the cardiotoxicity of PTX in tumor treatment. In this study, we initially injected PTX into mice to establish a myocardial cell apoptosis model to observe the degree of damage to mouse myocardium caused by PTX. Upon determining the levels of mouse myocardial creatine phosphokinase (CK), myokinase isoenzyme (CK-MB), aspartate transaminase (AST), and lactate dehydrogenase (LDH), we found that all of these levels showed apparent increases in mice treated with PTX. Further analyses of the TNF-α level and the expression of Jun N-terminal kinase (JNK) and Bcl-2 family-related proteins in myocardial tissue were performed. It was found that PTX increased the protein levels of TNF-α, Bax, p-JNK, and JNK in myocardial tissue but decreased the protein level of Bcl-2. After 1 month of PTX treatment in mice, we inhibited the expression of TNF-α and JNK proteins, which reduced the effect of paclitaxel on the apoptosis of mouse cardiomyocytes. The protein levels of Bax, p-JNK, and TNF-α in cardiomyocytes were reduced, while there was a relative increase in the Bcl-2 protein level. The findings suggested that inhibition of the NK signaling pathway and TNF-α can lessen the effect of PTX on mouse cardiomyocytes.

Involvement of kallikrein-PAR2-proinflammatory pathway in severe trastuzumab-induced cardiotoxicity

Trastuzumab‐induced cardiotoxicity interferes with continued treatment in approximately 10% of patients with ErbB2‐positive breast cancer, but its mechanism has not been fully elucidated. In this study, we recruited trastuzumab‐treated patients with ≥30% reduction in left ventricular ejection fraction (SP) and noncardiotoxic patients (NP). From each of these patients, we established three cases of induced pluripotent stem cell‐derived cardiomyocytes (pt‐iPSC‐CMs). Reduced contraction and relaxation velocities following trastuzumab treatment were more evident in SP pt‐iPSC‐CMs than NP pt‐iPSC‐CMs, indicating the cardiotoxicity phenotype could be replicated. Differences in ATP production, reactive oxygen species, and autophagy activity were observed between the two groups. Analysis of transcripts revealed enhanced kallikrein5 expression and pro‐inflammatory signaling pathways, such as interleukin‐1β, in SP pt‐iPSC‐CMs after trastuzumab treatment. The kallilkrein5‐protease‐activated receptor 2 (PAR2)‐MAPK signaling pathway was more activated in SP pt‐iPSC‐CMs, and treatment with a PAR2‐antagonist suppressed interleukin‐1β expression. Our data indicate enhanced pro‐inflammatory responses through kallikrein5‐PAR2 signaling and vulnerability to external stresses appear to be the cause of trastuzumab‐induced cardiotoxicity in SP.

A systematic review and meta-analysis of beta-blockers and renin-angiotensin system inhibitors for preventing left ventricular dysfunction due to anthracyclines or trastuzumab in patients with breast cancer

AIMS

Trastuzumab and anthracyclines, often used in the treatment of breast cancer, may impair myocardial function, and reduce left ventricular ejection fraction (LVEF), potentially causing heart failure. Randomized controlled trials (RCTs) have evaluated the effects of beta-blockers (BBs), angiotensin receptor blockers (ARBs), and angiotensin-converting enzyme inhibitors (ACEI) on trastuzumab- and anthracycline-associated cardiotoxicity. We report a meta-analysis of these RCTs in patients with breast cancer.

METHODS AND RESULTS

The primary analysis was on the effect of BBs and ACEI/ARBs on LVEF in patients treated with either trastuzumab or anthracyclines. A secondary analysis was done investigating the effect of BBs or ACEI/ARBs on LVEF in trastuzumab and anthracycline treatments. Only RCTs were included using the search term 'ARBs, ACEIs, BBs, anthracyclines, trastuzumab, and breast cancer' in PubMed, Embase, and CENTRAL up to 31 March 2021. A meta-analysis was conducted to estimate the mean difference (MD) in LVEF between intervention and placebo groups at follow-up. A total of nine RCTs (n = 1362) were included in the analysis. All patients were women. BBs and ACEI/ARBs were shown to attenuate the decline in LVEF during trastuzumab and anthracycline treatments [MD: 2.4; 95% confidence interval (CI): 0.3-4.2 and MD: 1.5; 95% CI: -0.6 to 3.7]. Compared with placebo, LVEF was significantly higher in patients assigned to BB or ACEI/ARB on trastuzumab (MD: 2.3; 95% CI: 0.0-4.6) but not on anthracyclines (MD: 1.9; 95% CI: -0.5 to 4.2).

CONCLUSION

Both BB and ACEI/ARB therapies were associated with the preservation of LVEF during trastuzumab and anthracycline-containing regimens as compared with placebo, suggesting both to be beneficial.

Cardiac complications of cancer therapies

The quest of defeating cancer and improving prognosis in survivors has generated remarkable strides forward in research and have advanced the development of new antineoplastic therapies. These achievements, combined with rapid screening and early detection, have considerably extended the life expectancy of patients surviving multiple types of malignancies. Consequently, chemotherapy-related toxicity in several organ systems, especially the cardiovascular system, has surfaced as one of the leading causes of morbidity and mortality among cancer survivors. Recent evidence classifies chemotherapy-induced cardiotoxicity as the second-leading cause of morbidity and mortality, closely comparing with secondary cancer malignancies. While a certain degree of cardiotoxicity has been reported to accompany most chemotherapies, including anthracyclines, anti-metabolites, and alkylating agents, even the latest targeted cancer therapies such as immune checkpoint inhibitors and tyrosine kinase inhibitors have been associated with acute and chronic cardiac sequelae. In this chapter, we focus on describing the principal mechanism(s) for each class of chemotherapeutic agents that lead to cardiotoxicity and the innovative translational research approaches that are currently being explored to prevent or treat cancer therapy-induced cardiotoxicity and related cardiac complications.

New Insights on the Toxicity on Heart and Vessels of Breast Cancer Therapies

Cardiovascular diseases are largely represented in patients with cancer and appear to be important side effects of cancer treatments, heavily affecting quality of life and leading to premature morbidity and death among cancer survivors. In particular, treatments for breast cancer have been shown to potentially play serious detrimental effects on cardiovascular health. This review aims to explore the available literature on breast cancer therapy-induced side effects on heart and vessels, illustrating the molecular mechanisms of cardiotoxicity known so far. Moreover, principles of cardiovascular risk assessment and management of cardiotoxicity in clinical practice will also be elucidated. Chemotherapy (anthracycline, taxanes, cyclophosphamide and 5-fluorouracil), hormonal therapy (estrogen receptor modulator and gonadotropin or luteinizing releasing hormone agonists) and targeted therapy (epidermal growth factor receptor 2 and Cyclin-dependent kinases 4 and 6 inhibitors) adverse events include arterial and pulmonary hypertension, supraventricular and ventricular arrhythmias, systolic and diastolic cardiac dysfunction and coronary artery diseases due to different and still not well-dissected molecular pathways. Therefore, cardiovascular prevention programs and treatment of cardiotoxicity appear to be crucial to improve morbidity and mortality of cancer survivors.

microRNA miR-133a as a Biomarker for Doxorubicin-Induced Cardiotoxicity in Women with Breast Cancer: A Signaling Pathway Investigation

Cardiovascular toxicity is the main adverse effect of Doxorubicin (DOX) in cancer patients. microRNAs (miRNAs) are promising biomarkers to identify cardiac injury induced by DOX in breast cancer patients during the subclinical phase. Using RT-qPCR, we compared the expression of circulating miR-208a5p, miR-133a, miR-499a5p, miR-15a, miR-133b, and miR-49a3p in serum samples from DOX-induced cardiotoxicity (case) compared to the non-cardiotoxicity group (control). To further explore the potential roles of these circulating miRNA in cardiotoxicity, we searched the miRTarBase for experimentally validated miRNA-target interactions and performed a functional enrichment analysis based on those interactions. miR-133a was significantly upregulated in case compared to control group. The most relevant pathway regulated by miR-133a was ErbB2 signaling, whose main genes involved are EGFR, ERBB2, and RHOA, which are possibly downregulated by miR133a. The other miRNAs did not show significant differential expression when compared on both groups. The data suggest that miR-133a is associated with DOX-based cardiotoxicity during chemotherapy in breast cancer patients through ErbB2 signaling pathway. Moreover, miR-133a may be a future marker of DOX-induced cardiotoxicity in women with breast cancer.

Cardiotoxicity of Non-Anthracycline Cancer Chemotherapy Agents

Throughout the last decades, newly developed chemotherapeutic agents and immunotherapies that target signaling pathways have provided patients with better prognoses, improved their quality of life and increased survival rates, thus converting cancer to a stable chronic disease. However, non-anthracycline cancer chemotherapy agents and immunotherapies including human epidermal growth factor receptor 2 (HER2) inhibitors, vascular endothelial growth factor (VEGF) inhibitors, Bcr-Abl tyrosine-kinase inhibitors (TKI), proteasome inhibitors, immune checkpoint inhibitors and chimeric antigen receptor T cells (CAR-T cells) may cause cardiovascular toxicity events and complications that usually interrupt the continuation of an appropriate treatment regimen, which induces life-threatening risks or leads to long-term morbidity. Heart failure, cardiac arrythmias and cardiomyopathies are the most common cardiovascular events related to cardiotoxicity due to chemotherapy. Each patient should be carefully assessed and monitored before, during and after the administration of chemotherapy, to address any predisposing risk factors and the new onset of cardiotoxicity manifestations early and treat them appropriately. The development of novel anticancer agents that cause minimal cardiovascular toxicity events or novel agents that ameliorate the adverse effects of the existing anticancer agents could drastically change the field of cardio-oncology. The aim of this narrative review is to demonstrate new knowledge regarding the screening and diagnosis of non-anthracycline-induced cardiotoxicity and to propose protective measures that could be performed in order to achieve the delivery of optimal care.

Development of an efficient mAb quantification assay by LC-MS/MS using rapid on-bead digestion

The use of monoclonal antibody (mAb) therapeutics is increasing rapidly, but mAb concentrations vary widely between individuals and might subsequently affect mAb exposure and treatment response. Precision medicine has gained much attention in recent years, but little is known about the personalized dosage of mAb therapeutics. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been demonstrated as a selective and sensitive approach to quantify mAb therapeutics in biological samples, but current methods to quantify mAbs are usually time-consuming and require tedious sample preparation. This study developed an efficient LC-MS/MS method using an on-bead trypsin digestion procedure at a higher digestion temperature. Five mAbs, bevacizumab, evolocumab, nivolumab, pembrolizumab, and trastuzumab, used for treating different diseases, were selected for method development. Tocilizumab was selected as the internal standard. The result of the on-bead digestion protocol was compared to the conventional low-pH elution method, and it showed better sensitivity and reproducibility for most mAbs. The optimized on-bead digestion protocol used 75 μL of digestion buffer at 60 °C for a 60 min digestion. The calibration curve was generated from 10 to 200 μg mL^-1. The accuracies at the three QC levels of the 5 mAbs were all within 94.5 ± 5.2% to 111.6 ± 3.7%. The repeatability and intermediate precision of the 5 mAbs were all lower than 6.1 and 9.5% RSD, respectively. The newly developed method was successfully applied to quantify trastuzumab in six breast cancer patients under different treatment cycles, and the concentrations ranged from 66.4 to 173.2 μg mL^-1. In conclusion, the developed method is more efficient and more practical for real-world analysis of a large number of clinical samples, it could be used for routine therapeutic drug monitoring, and it could contribute to personalized mAb treatment.

Trastuzumab-Induced Negative Chronotropic and Lusitropic Effects in Cynomolgus Monkeys

ABSTRACT

Treatment with trastuzumab, an antihuman epidermal growth factor receptor type 2 humanized monoclonal antibody, has been associated with heart failure in certain patients with cancer; however, the mechanism underlying trastuzumab-induced cardiac dysfunction remains unclear. This study was conducted to clarify the cardiac effects of trastuzumab in cynomolgus monkeys, which are commonly used as cross-reactive species in preclinical safety evaluation. Monkeys were treated with trastuzumab weekly for 1 month (5 doses in total). At first and fifth doses for pressure-volume loop analysis, trastuzumab at 20 mg·kg-1·10 min-1, equivalent to the human therapeutic dose, was administered intravenously to isoflurane-anesthetized animals, followed by 60 mg·kg-1·10 min-1 at a 30-minute interval. The other doses were fixed at 80 mg·kg-1·10 min-1 under unanesthetized conditions. After the first dose, reduced heart rate, decreases in maximal rate of fall of left ventricular pressure, and prolonged time constant for isovolumic relaxation, which are predictors of drug-induced changes in lusitropy, were observed at 20 and 60 mg·kg-1. The changes after the fifth dose were comparable with those after the first dose, indicating trastuzumab did not show exacerbation of cardiac function during the 1-month trial. No significant changes in slope of preload recruitable stroke work, which is a load-independent inotropic parameter, were observed at either dose. In conclusion, trastuzumab-induced little inotropic effect but induced negative chronotropic or lusitropic effects in monkeys, which might be associated with impaired left ventricular diastolic function.

Stepping forward in antibody-drug conjugate development

Antibody-drug conjugates (ADCs) are cancer therapeutic agents comprised of an antibody, a linker and a small-molecule payload. ADCs use the specificity of the antibody to target the toxic payload to tumor cells. After intravenous administration, ADCs enter circulation, distribute to tumor tissues and bind to the tumor surface antigen. The antigen then undergoes endocytosis to internalize the ADC into tumor cells, where it is transported to lysosomes to release the payload. The released toxic payloads can induce apoptosis through DNA damage or microtubule inhibition and can kill surrounding cancer cells through the bystander effect. The first ADC drug was approved by the United States Food and Drug Administration (FDA) in 2000, but the following decade saw no new approved ADC drugs. From 2011 to 2018, four ADC drugs were approved, while in 2019 and 2020 five more ADCs entered the market. This demonstrates an increasing trend for the clinical development of ADCs. This review summarizes the recent clinical research, with a specific focus on how the in vivo processing of ADCs influences their design. We aim to provide comprehensive information about current ADCs to facilitate future development.

OUP accepted manuscript

Aim

Methods

Results

Conclusions

Cancer Therapy-Induced Cardiotoxicity-A Metabolic Perspective on Pathogenesis, Diagnosis and Therapy

Long-term cardiovascular complications of cancer therapy are becoming ever more prevalent due to increased numbers of cancer survivors. Cancer therapy-induced cardiotoxicity (CTIC) is an incompletely understood consequence of various chemotherapies, targeted anti-cancer agents and radiation therapy. It is typically detected clinically by a reduction in cardiac left ventricular ejection fraction, assessed by echocardiography. However, once cardiac functional decline is apparent, this indicates irreversible cardiac damage, highlighting a need for the development of diagnostics which can detect CTIC prior to the onset of functional decline. There is increasing evidence to suggest that pathological alterations to cardiac metabolism play a crucial role in the development of CTIC. This review discusses the metabolic alterations and mechanisms which occur in the development of CTIC, with a focus on doxorubicin, trastuzumab, imatinib, ponatinib, sunitinib and radiotherapy. Potential methods to diagnose and predict CTIC prior to functional cardiac decline in the clinic are evaluated, with a view to both biomarker and imaging-based approaches. Finally, the therapeutic potential of therapies which manipulate cardiac metabolism in the context of adjuvant cardioprotection against CTIC is examined. Together, an integrated view of the role of metabolism in pathogenesis, diagnosis and treatment is presented.

Comparison of Anticancer Drug Toxicities: Paradigm Shift in Adverse Effect Profile

The inception of cancer treatment with chemotherapeutics began in the 1940s with nitrogen mustards that were initially employed as weapons in World War II. Since then, treatment options for different malignancies have evolved over the period of last seventy years. Until the late 1990s, all the chemotherapeutic agents were small molecule chemicals with a highly nonspecific and severe toxicity spectrum. With the landmark approval of rituximab in 1997, a new horizon has opened up for numerous therapeutic antibodies in solid and hematological cancers. Although this transition to large molecules improved the survival and quality of life of cancer patients, this has also coincided with the change in adverse effect patterns. Typically, the anticancer agents are fraught with multifarious adverse effects that negatively impact different organs of cancer patients, which ultimately aggravate their sufferings. In contrast to the small molecules, anticancer antibodies are more targeted toward cancer signaling pathways and exhibit fewer side effects than traditional small molecule chemotherapy treatments. Nevertheless, the interference with the immune system triggers serious inflammation- and infection-related adverse effects. The differences in drug disposition and interaction with human basal pathways contribute to this paradigm shift in adverse effect profile. It is critical that healthcare team members gain a thorough insight of the adverse effect differences between the agents discovered during the last twenty-five years and before. In this review, we summarized the general mechanisms and adverse effects of small and large molecule anticancer drugs that would further our understanding on the toxicity patterns of chemotherapeutic regimens.

Circulating Natural Autoantibodies to HER2-Derived Peptides Performed Antitumor Effects on Oral Squamous Cell Carcinoma

Natural autoantibodies play a crucial role in destruction of malignant tumors due to immune surveillance function. Epidermal growth factor receptor 2 (HER2) has been found to be highly expressed in a variety of epithelial tumors including oral squamous cell carcinoma (OSCC). The present study was thus undertaken to investigate the effect of anti-HER2 natural autoantibodies on OSCC. Compared with cancer-adjacent tissues, cancer tissues from OSCC patients exhibited higher HER2 expression especially in those with middle & advanced stage OSCC. Plasma anti-HER2 IgG levels examined with an enzyme-linked immunosorbent assay (ELISA) developed in-house showed differences between control subjects, individuals with oral benign tumor and patients with OSCC. In addition, anti-HER2 IgG-abundant plasma was screened from healthy donors to treat OSCC cells and to prepare for anti-HER2 intravenous immunoglobulin (IVIg). Both anti-HER2 IgG-abundant plasma and anti-HER2 IVIg could significantly inhibit proliferation and invasion of OSCC cells by inducing the apoptosis, and also regulate apoptosis-associated factors and epithelial-mesenchymal transition (EMT), respectively. Besides, the complement-dependent cytotoxicity (CDC) pathway was likely to contribute to the anti-HER2 IgG mediated inhibition of OSCC cells. After the HER2 gene was knocked down with HER2-specific siRNAs, the inhibitory effects on OSCC cell proliferation and apoptotic induction faded away. In conclusion, human plasma IgG, or IVIg against HER2 may be a promising agent for anti-OSCC therapy.

Relationship between Chemotherapy and Atrial Fibrillation: Clinical Case

The aim of this article is to represent the characterization of the clinical case of chemotherapy-related atrial fibrillation (AF) development in the young woman, elaborated as a result of multiple neoadjuvant and adjuvant modes of the intake of chemotherapy (both anthracycline based and non-anthracycline ones). In this case, the noted disturbances of heart rhythm should be recognized as a manifestation of cardiotoxicity. The latter implies the degree of detrimental effect of chemotherapeutical medication on the morphophynctional parameters of the cardiovascular system. Anthracycline drugs, being highly effective chemotherapytical agents, provide well-known toxic effects on the heart and vessels. Anthracycline mediated cardiotoxicity is a well- known veracity that dates back to the 60s of the last century, but up to now this medication sustains irreplaceable components of big volume of chemotherapy modes. Moreover, it should be noted that relatively newer drugs also posses certain cardiotoxicogenic potential.

Fusion of apoptosis-related protein Cytochrome c with anti-HER-2 single-chain antibody targets the suppression of HER-2+ breast cancer

Cancer treatment has gradually developed from toxic chemotherapy to targeted therapy with fewer side effects. Approximately 30% of breast cancer patients overexpress human epidermal growth factor receptor 2 (HER-2). Previous studies have successfully produced single-chain antibodies (scFv) targeting HER-2+ breast cancer; however, scFv have poor stability, easy aggregation and a shorter half-life, which have no significant effect on targeting therapy. Moreover, scFv has been considered as a drug delivery platform that can kill target cells by effector molecules. However, the functional killing domains of immunotoxins are mainly derived from plant or bacterial toxins, which have a large molecular weight, low tissue permeability and severe side effects. To address these concerns, we designed several apoptotic immune molecules to replace exogenous toxins using endogenous apoptosis-related protein DNA fragmentation factor 40 (DFF40) and tandem-repeat Cytochrome c base on caspase-3 responsive peptide (DEVD). Our results suggest that DFF40 or Cytc fusion scFv specifically targets HER-2 overexpressing breast cancer cells (SK-BR-3 and BT-474) rather than HER-2 negative cells (MDA-MB-231 and MCF-7). Following cellular internalization, apoptosis-related proteins inhibited tumour activity by initiating endogenous apoptosis pathways, which significantly reduced immunogenicity and toxic side effects. Therefore, we suggest that immunoapoptotic molecules may become potential drugs for targeted immunotherapy of breast cancer.

Exercise to Reduce Anthracycline-Mediated Cardiovascular Complications in Breast Cancer Survivors

While developments in cancer therapeutics have greatly reduced morbidity and mortality in females with breast cancer, it comes at a cost of an increased risk of cardiovascular complications. In particular, anthracyclines, like doxorubicin, which are a mainstay of current chemotherapy regimens, are associated with dose-dependent cardiotoxicity. Exercise has been widely accepted as an effective intervention in reducing cardiovascular risk in a variety of different clinical conditions. However, the benefits of exercise in anthracycline-mediated cardiotoxicity are not clearly understood. First, this review discusses the pre-clinical studies which have elucidated the cardioprotective mechanisms of aerobic and resistance exercise in improving cardiovascular function in the setting of anthracycline treatment. Next, it aims to summarize the results of aerobic and resistance exercise clinical trials conducted in females with breast cancer who received anthracycline-based chemotherapy. The review further discusses the current exercise guidelines for women undergoing chemotherapy and contraindications for exercise. Finally, the review addresses gaps in research, specifically the need for further clinical trials to establish a recommended exercise prescription within this patient population.

Health-Related Quality of Life Among Patients With HR+/HER2- Early Breast Cancer

PURPOSE

The goal of this study was to characterize health-related quality of life (HRQOL) among patients diagnosed with early-stage, hormone receptor-positive (HR+)/human epidermal growth factor receptor 2 negative (HER2-) breast cancer.

METHODS

A multinational (United States, Japan, France, Germany, Italy, Spain, and United Kingdom) study of patients diagnosed with stage I to III HR+/HER2- breast cancer, either receiving adjuvant treatment or under postadjuvant surveillance, was conducted between June and October 2019. Patients were identified by their consulting physician and invited to complete the Functional Assessment of Cancer Therapy-Breast (FACT-B) and the EQ-5D-5L pen and paper questionnaires. EQ-5D-5L index scores were derived by using available country-specific health state value sets, where available, and numerically compared with general population scores derived from published normative and population data. Descriptive summary statistics were reported for FACT-B, Functional Assessment of Cancer Therapy-General (FACT-G) (total and specific subscales), the EQ-5D index scores, and the EQ-VAS scores for each country. Results were stratified according to disease-free treatment status (active adjuvant treatment or postadjuvant surveillance), age (25-44, 45-54, 55-64, or ≥65 years), stage (I, II, or III), and menopausal status at the time of questionnaire completion (pre-/peri-menopausal or postmenopausal).

FINDINGS

Overall, 1110 patients completed the HRQOL questionnaires (mean age, 59 years; 79% active adjuvant treatment, and 21% under surveillance postadjuvant treatment at time of questionnaire administration; 31% stage I, 48% stage II, and 20% stage III at diagnosis). Of these, 1102 completed the FACT-B and 1083 completed the EQ-5D-5L questionnaires. The mean (SD) FACT-B total score was 99.0 (21.9). The mean FACT-G total score was 72.5 (17.8), which was comparable to the published normative score. The mean EQ-5D index and EQ-VAS scores for each country were similar to corresponding population means; EQ-5D index scores ranged from 0.842 (0.098) in Japan to 0.916 (0.109) in France, and EQ-VAS scores from 68.0 (18.4) in Germany to 78.6 (16.4) in the United States. In addition, mean scores were comparable between the active adjuvant treatment and postadjuvant surveillance groups for the FACT-B total (99.4 [22.5] and 97.7 [19.7], respectively), FACT-G total (72.8 [18.3] and 71.3 [16.0]), EQ-5D index score (0.868 [0.135] and 0.869 [0.142]), and EQ-VAS (74.9 [17.2] and 74.4 [16.1]).

IMPLICATIONS

Patient-reported HRQOL among patients with HR+/HER2- early breast cancer who were disease-free was high, with reported scores comparable to normative scores. These results improve our understanding of HRQOL among patients with early disease and may facilitate future studies examining the potential impact of adjuvant treatment and disease recurrence, including metastasis.

An update of the molecular mechanisms underlying doxorubicin plus trastuzumab induced cardiotoxicity

Cardiotoxicity is a major side effect of the chemotherapeutic drug doxorubicin (Dox), which is further exacerbated when it is combined with trastuzumab, a standard care approach for Human Epidermal growth factor Receptor-type 2 (HER2) positive cancer patients. However, the molecular mechanisms of the underlying cardiotoxicity of this combination are still mostly elusive. Increased oxidative stress, impaired energetic substrate uses and topoisomerase IIB inhibition are among the biological processes proposed to explain Dox-induced cardiomyocyte dysfunction. Since cardiomyocytes express HER2, trastuzumab can also damage these cells by interfering with neuroregulin-1 signaling and mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K)/Akt and focal adhesion kinase (FAK)-dependent pathways. Nevertheless, Dox and trastuzumab target other cardiac cell types, such as endothelial cells, fibroblasts, cardiac progenitor cells and leukocytes, which can contribute to the clinical cardiotoxicity observed. This review aims to summarize the current knowledge on the cardiac signaling pathways modulated by these two antineoplastic drugs highly used in the management of breast cancer, not only focusing on cardiomyocytes but also to broaden the knowledge of the potential impact on other cells found in the heart.

Long-term efficacy and safety of CT-P6 versus trastuzumab in patients with HER2-positive early breast cancer: final results from a randomized phase III trial

PURPOSE

Equivalent efficacy was demonstrated for the biosimilar CT-P6 and trastuzumab following neoadjuvant therapy for patients with human epidermal growth factor receptor-2 (HER2)-positive early breast cancer. Following adjuvant treatment, efficacy and safety were comparable between treatments. We report updated safety and efficacy data after up to 3 years' follow-up.

METHODS

Following neoadjuvant chemotherapy with CT-P6/trastuzumab, patients underwent surgery and continued receiving adjuvant CT-P6/trastuzumab. The primary endpoint (previously reported) was pathological complete response. Time-to-event analyses (disease-free survival [DFS], progression-free survival [PFS], and overall survival [OS]), study drug-related and cardiac adverse events, and immunogenicity were assessed during post-treatment follow-up.

RESULTS

Most patients entered the follow-up period (CT-P6: 259 [95.6%]; trastuzumab: 269 [96.8%]). After a median follow-up of 38.7 (CT-P6) and 39.6 (trastuzumab) months, medians were not reached for time-to-event parameters; estimated hazard ratios (HRs) and 3-year survival rates were similar between groups. Estimated HRs (95% confidence intervals) for CT-P6 versus trastuzumab were 1.23 (0.78-1.93) for DFS, 1.31 (0.86-2.01) for PFS, and 1.10 (0.57-2.13) for OS (intention-to-treat population). Safety findings were comparable between groups for the overall study and follow-up period, including study drug-related cardiac disorders (CT-P6: 22 [8.1%] patients; trastuzumab: 24 [8.6%] patients [overall]) and decreases in left ventricular ejection fraction. Immunogenicity was similar between groups.

CONCLUSION

The similarity of the time-to-event analyses between CT-P6 and trastuzumab supports the equivalence in terms of efficacy established for the primary endpoint. CT-P6 was well tolerated, with comparable safety and immunogenicity to trastuzumab. ClinicalTrials.gov: NCT02162667 (registered June 13, 2014).

In Situ Delivery and Production System (iDPS) of Anti-Cancer Molecules with Gene-Engineered Bifidobacterium

To selectively and continuously produce anti-cancer molecules specifically in malignant tumors, we have established an in situ delivery and production system (iDPS) with Bifidobacterium as a micro-factory of various anti-cancer agents. By focusing on the characteristic hypoxia in cancer tissue for a tumor-specific target, we employed a gene-engineered obligate anaerobic and non-pathogenic bacterium, Bifidobacterium, as a tool for systemic drug administration. This review presents and discusses the anti-tumor effects and safety of the iDPS production of numerous anti-cancer molecules and addresses the problems to be improved by directing attention mainly to the hallmark vasculature and so-called enhanced permeability and retention effect of tumors.

Durable Clinical Response to Immune and Targeted Therapies in an Elderly Man with Synchronous Gastric (HER2+) and Bladder Cancers: Case Report and Literature Review

Synchronous occurrences of gastric cancer positive for human epidermal growth factor receptor 2 (HER2+) and bladder cancer are rarely encountered in clinical practice. When and how to effectively treat both tumors, without compounding adverse effects, must be addressed. Herein, we describe an elderly man who presented with both gastric cancer (HER2+) and bladder cancer. Due to enlarged and fused lymph nodal metastasis, he was ill-suited for stomach resection. After transurethral resection of the bladder tumor, we administered both chemotherapy and the targeted agent trastuzumab. Gastric cancer showed partial response however bladder cancer recurred following two cycles of this regimen, the adverse effects were prohibitive, prompting refusal of further chemotherapy and radiotherapy. He then received the immune checkpoint inhibitor (ICI) nivolumab and trastuzumab in combination. This particular regimen successfully controlled both cancers and substantially improved the patient’s quality of life. Its long-term use did not intensify adverse reactions, enabling a progression-free survival of 21 months to date. We have also reviewed other published clinical strategies applied in rare instances of multiple primary malignancies as a reference for treating such patients.

Clinical predictors of cardiac toxicity in HER2-positive early breast cancer patients treated with adjuvant s.c. versus i.v. trastuzumab

BACKGROUND

Few data are available about real-life cardiotoxicity associated with s.c. versus i.v. trastuzumab treatment of early-stage, HER2-positive breast cancer, and little is known about its predisposing factors.

PATIENTS AND METHODS

We retrospectively reviewed data of 363 adult patients treated with adjuvant trastuzumab for HER2-positive breast cancer. Univariate statistical analysis was performed, and a multivariable logistic model was developed to identify independent risk factors of cardiac toxicity.

RESULTS

Within 5 years, the overall incidence of events meeting our criteria was 11.8%, and an early discontinuation of trastuzumab was recorded in 20 patients (5.5%). No cases of congestive heart failure occurred, neither multiple events per patient were observed. A total of 184 patients received i.v. and 179 received s.c. trastuzumab. Compared with the s.c. formulation, a higher cardiotoxicity rate for the i.v. administration (15.2% vs 8.4%) was found, and particularly in those patients with cardiovascular risk factors (19.3% vs 8.7%), at the univariate and multivariate analyses. Although more patients with prior anthracycline-based chemotherapy experienced cardiac events, the association of this therapy with cardiac events was not significant. The incidence of cardiac events was not influenced by anthropometric data (e.g. body mass index) or a diagnosis of diabetes mellitus. 5-year event-free survival was 91.7% in the overall population; event-free survival rates were similar between the s.c. and the i.v. groups.

CONCLUSION

Our study shows a more favorable safety profile of s.c. versus i.v trastuzumab administration. The use of s.c. trastuzumab could be advisable in at-risk patients.