Breast cancer therapy and cardiovascular risk: focus on trastuzumab

The Risk of Cancer-Associated and Radiotherapy-Associated Cardiovascular Diseases among Patients with Breast Cancer

BACKGROUND

The cardio-related issues should be emphasized as the survival rates of breast cancer increased. We investigated the risk of coronary artery disease (CAD) and stroke due to breast cancer or radiotherapy.

METHODS

In this retrospective cohort study, breast cancer patients diagnosed between 2007 and 2016 were recruited from Taiwan Cancer Registry Database and were followed until the end of 2018 by linking with the Taiwan National Health Insurance Database. The general population was randomly selected from the whole population in 2007. Standardized incidence ratios (SIR) were calculated to compare the risk of CAD and stroke between patients and the general population. Within the cohort, we included the patients diagnosed between 2011 and 2016. Cox proportional hazards model and subdistribution hazard function were used to investigate the associations of radiotherapy with the risk of CAD and stroke.

RESULTS

Overall SIR of CAD was 0.82 (95% confidence interval [CI]: 0.78-0.86), while were 1.43 and 1.08 (95% CI: 1.30-1.55 and 1.00-1.16) 1 and 2 years after diagnosis, respectively. Overall SIR of stroke was 0.63 (95% CI: 0.60-0.67), the results were similar after considering the time since diagnosis. The adjusted hazard ratios (HR) for the associations of radiotherapy with CAD and stroke risk were 0.91 (95% [CI] = 0.76-1.09) and 0.84 (95% CI = 0.68-1.04), respectively. The results were similar by using subdistribution hazard function.

CONCLUSIONS

The risk of CAD was higher within the first 2 years of breast cancer diagnosis. We found no association between radiotherapy and the risk of CAD and stroke.

A pan-cancer analysis of Dyskeratosis congenita 1 (DKC1) as a prognostic biomarker

BACKGROUND

Dyskeratosis congenita 1 (DKC1), a critical component of telomerase complex, is highly expressed in a variety of human cancers. However, the association of DKC1 with cancer occurrence and development stages is not clear, making a pan-cancer analysis crucial.

METHODS

We conducted a study using various bioinformatic databases such as TIMER, GEPIA, UALCAN, and KM plotter Analysis to examine the different expressions of DKC1 in multiple tissues and its correlation with pathological stages. Through KEGG analysis, GO enrichment analysis and Venn analysis, we were able to reveal DKC1-associated genes and signaling pathways. In addition, we performed several tests including the CCK, wound healing assay, cell cycle arrest assay, transwell assay and Sa-β-gal staining on DKC1-deleted MDA-231 cells.

RESULTS

Our study demonstrates that DKC1 has relatively low expression specificity in different tissues. Furthermore, we found that in ACC, KICH, KIRP and LIHC, the expression level of DKC1 is positively correlated with pathological stages. Conversely, in NHSC, KIRP, LGG, LIHC, MESO and SARC, we observed a negative influence of DKC1 expression level on the overall survival rate. We also found a significant positive correlation between DKC1 expression and Tumor Mutational Burden in 14 tumors. Additionally, we observed a significantly negative impact of DKC1 DNA methylation on gene expression at the promoter region in BRCA. We also identified numerous phosphorylation sites concentrated at the C-terminus of the DKC1 protein. Our GO analysis revealed a correlation between DKC1 and ribosomal biosynthesis pathways, and the common element UTP14A was identified. We also observed decreased rates of cell proliferation, migration and invasion abilities in DKC1-knockout MDA-MB-231 cell lines. Furthermore, DKC1-knockout induced cell cycle arrest and caused cell senescence.

CONCLUSIONS

Our findings suggest that the precise expression of DKC1 is closely associated with the occurrence and developmental stages of cancer in multiple tissues. Depletion of DKC1 can inhibit the abilities of cancer cells to proliferate, migrate, and invade by arresting the cell cycle and inducing cell senescence. Therefore, DKC1 may be a valuable prognostic biomarker for the diagnosis and treatment of cancer in various tissues.

FBXO3 stabilizes USP4 and Twist1 to promote PI3K-mediated breast cancer metastasis

Tumor metastasis is the major cause of breast cancer morbidity and mortality. It has been reported that the F-box protein FBXO3 functions as an E3 ubiquitin ligase in regulating various biological processes, including host autoimmune, antiviral innate immunity, and inflammatory response. However, the role of FBXO3 in tumor metastasis remains elusive. We have previously shown that ΔNp63α is a common inhibitory target in oncogene-induced cell motility and tumor metastasis. In this study, we show that FBXO3 plays a vital role in PI3K-mediated breast cancer metastasis independent of its E3 ligase activity and ΔNp63α in breast cancer cells and in mouse. FBXO3 can bind to and stabilize USP4, leading to Twist1 protein stabilization and increased breast cancer cell migration and tumor metastasis. Mechanistically, FBXO3 disrupts the interaction between USP4 and aspartyl aminopeptidase (DNPEP), thereby protecting USP4 from DNPEP-mediated degradation. Furthermore, p110αH1047R facilitates the phosphorylation and stabilization of FBXO3 in an ERK1-dependent manner. Knockdown of either FBXO3 or USP4 leads to significant inhibition of PI3K-induced breast cancer metastasis. Clinically, elevated expression of p110α/FBXO3/USP4/Twist1 is associated with poor overall survival (OS) and recurrence-free survival (RFS) of breast cancer patients. Taken together, this study reveals that the FBXO3-USP4-Twist1 axis is pivotal in PI3K-mediated breast tumor metastasis and that FBXO3/USP4 may be potential therapeutic targets for breast cancer treatment.

Prolonged impact of anti-cancer therapy on endothelial function and arterial stiffness in breast cancer patients

BACKGROUND

Cardiotoxicity restricts anthracycline and trastuzumab treatment of Human Epidermal Growth Factor Receptor 2 positive early breast cancer. Endothelial dysfunction and arteriosclerosis are significant cardiovascular risk factors.

OBJECTIVES

We studied the effect of anthracycline-based chemotherapy, with or without trastuzumab, on endothelium and arteriosclerosis in patients with breast cancer.

METHODS

In this case-control study, 52 women with breast cancer and 104 women without breast cancer were examined longitudinally up to 15 months following (in the breast cancer group) initiation of chemotherapy. Arterial stiffness was evaluated through pulse wave velocity (PWV), while endothelial function via flow-mediated dilatation (FMD) at baseline (T0), 3 (T1), 6 (T2), and 15 (T3) months later.

RESULTS

There was no difference between subjects with breast cancer and control in PWV and FMD at baseline. Longitudinally, participants with breast cancer exhibited considerable impairment of PWV and FMD compared to the control group (p for interaction <0.001 for both parameters). In breast cancer patients, there was a significant increase from T0 to T3 in PWV (7.43 ± 1.68 m/s vs. 8.18 ± 2.00 m/s, p = 0.01) and decrease in FMD (6.95 ± 2.86% vs. 5.03 ± 2.83%, p = 0.006). The addition of trastuzumab in the treatment did not have any effect on PWV (p = 0.74) or FMD (p = 0.91).

CONCLUSIONS

In patients with breast cancer, there is progression of endothelial dysfunction and arteriosclerosis up to 15 months following initiation of anthracycline-based chemotherapy. Trastuzumab has no additive effect on endothelial function or arterial stiffness.

Cardiotoxicity from neoadjuvant targeted treatment for breast cancer prior to surgery

Cancer treatment has been gradually shifting from non-specific cytotoxic agents to molecularly targeted drugs. Breast cancer (BC), a malignant tumor with one of the highest incidence worldwide, has seen a rapid development in terms of targeted therapies, leading to a radical change in the treatment paradigm. However, the use of targeted drugs is accompanied by an increasing rate of deaths due to non-tumor-related causes in BC patients, with cardiovascular complications as the most common cause. Cardiovascular toxicity during antitumor therapy has become a high-risk factor for survival in BC patients. Targeted drug-induced cardiotoxicity exerts a wide range of effects on cardiac structure and function, including conduction disturbances, QT interval prolongation, impaired myocardial contractility, myocardial fibrosis, and hypertrophy, resulting in various clinical manifestations, e.g., arrhythmias, cardiomyopathy, heart failure, and even sudden death. In adult patients, the incidence of antitumor targeted drug-induced cardiotoxicity can reach 50%, and current preclinical evaluation tools are often insufficiently effective in predicting clinical cardiotoxicity. Herein, we reviewed the current status of the occurrence, causative mechanisms, monitoring methods, and progress in the prevention and treatment of cardiotoxicity associated with preoperative neoadjuvant targeted therapy for BC. It supplements the absence of relevant review on the latest research progress of preoperative neoadjuvant targeted therapy for cardiotoxicity, with a view to providing more reference for clinical treatment of BC patients.

Two-dimensional speckle tracking echocardiography help identify breast cancer therapeutics–related cardiac dysfunction

Background

Cancer therapeutics–related cardiac dysfunction (CTRCD) from different chemotherapy strategies are underdetermined by echocardiography. As an imaging marker of subclinical cardiac dysfunction, two-dimensional speckle tracking echocardiography (2D-STE) may assist in identifying the impact patterns of different CTRCD.

Methods

A total of 67 consecutive patients with invasive ductal breast carcinoma who will undertake neoadjuvant chemotherapy were enrolled and grouped according to their different chemotherapy regimens based on their biopsy results. Group A included 34 patients who received anthracycline without trastuzumab, whereas Group B had 33 patients who received trastuzumab without anthracycline. Echocardiography was performed at three time-points, i.e., baseline (T0), cycle-2 (T2), and cycle-4 (T4) of chemotherapy. Conventional echocardiographic measurements and 2D-STE strain values, and myocardial work (MW) parameters, were compared between different groups at different time-points.

Results

The mean age had no statistical difference between the two groups. E/e′ was the only conventional echocardiographic parameter that had variation in group A (P < 0.05). Compared with baseline, GLS in group A decreased at T2, and GCS decreased at T4 (P < 0.05). GLS and GCS in group B both decreased at T4 (P < 0.05). More patients in group A had a more than 15% fall of baseline GLS rather than GCS at T2 (P < 0.05), however, there was no difference of either GLS or GCS decline rate at T4 between the two groups. All the MW parameters in group A had variations overtime, whereas only GCW in group B (P < 0.05).

Conclusion

Early subclinical myocardial dysfunction can be identified by 2D-STE in breast cancer patients with chemotherapy, and GLS provides profound value in demonstrating the temporal changes in early myocardial damage induced by anthracycline. LV contractility injury in patients with trastuzumab may be mild at first but increases in severity with exposure time as early as cycle-4. Awareness of these differences may help to stratify the prevention of late cardiovascular events caused by different CTRCDs. In addition, GCW may be the most sensitive myocardial work parameter of CTRCD.

Emerging mitochondrial signaling mechanisms in cardio-oncology: beyond oxidative stress

Many anticancer therapies (CTx) have cardiotoxic side effects that limit their therapeutic potential and cause long-term cardiovascular complications in cancer survivors. This has given rise to the field of cardio-oncology, which recognizes the need for basic, translational, and clinical research focused on understanding the complex signaling events that drive CTx-induced cardiovascular toxicity. Several CTx agents cause mitochondrial damage in the form of mitochondrial DNA deletions, mutations, and suppression of respiratory function and ATP production. In this review, we provide a brief overview of the cardiovascular complications of clinically used CTx agents and discuss current knowledge of local and systemic secondary signaling events that arise in response to mitochondrial stress/damage. Mitochondrial oxidative stress has long been recognized as a contributor to CTx-induced cardiotoxicity; thus, we focus on emerging roles for mitochondria in epigenetic regulation, innate immunity, and signaling via noncoding RNAs and mitochondrial hormones. Because data exploring mitochondrial secondary signaling in the context of cardio-oncology are limited, we also draw upon clinical and preclinical studies, which have examined these pathways in other relevant pathologies.

Chemotherapy-associated cardiomyopathy: Mechanisms of toxicity and cardioprotective strategies

OBJECTIVE

To describe the proposed mechanisms of chemotherapy-associated cardiomyopathy (CAC) and potential cardioprotective therapies for CAC including a comprehensive review of existing systematic analyses, guideline recommendations, and ongoing clinical trials.

DATA SOURCES

A literature search of MEDLINE was performed (from 1990 to June 2020) using the following search terms: anthracycline, trastuzumab, cardiomyopathy, cardiotoxicity, primary prevention, angiotensin-converting enzyme inhibitor (ACEI), angiotensin receptor blocker (ARB), beta blocker, dexrazoxane (DEX) as well as using individual names from select therapeutic categories.

STUDY SELECTION AND DATA EXTRACTION

Existing English language systematic analyses and guidelines were considered.

DATA SYNTHESIS

The mechanisms of CAC are multifaceted, but various cardioprotective therapies target many of these pathways. To date, anthracyclines and HER-2 targeted therapies have been the focus of cardioprotective trials to date as they are the most commonly implicated therapies in CAC. While traditional neurohormonal antagonists (ACEIs, ARBs, and beta blockers) and DEX performed favorably in many small clinical trials, the quality of available evidence remains limited. Hence, major guidelines lack consensus on an approach to primary prevention of CAC. Given the uncertain role of preventive therapy, monitoring for a symptomatic or asymptomatic decline in LV function is imperative with prompt evaluation should this occur. Numerous ongoing randomized controlled trials seek to either confirm the findings of these previous studies or identify new therapeutic agents to prevent CAC. Clinical implications are derived from the available literature as well as current guideline recommendations for CAC cardioprotection.

CONCLUSION

At this time, no single therapy has a clear cardioprotective benefit in preventing CAC nor is any therapy strongly recommended by current guidelines. Additional studies are needed to determine the optimal preventative regimens.

Bio-vehicles of cytotoxic drugs for delivery to tumor specific targets for cancer precision therapy

Abnormal structural and molecular changes in malignant tissues were thoroughly investigated and utilized to target tumor cells, hence rescuing normal healthy tissues and lowering the unwanted side effects as non-specific cytotoxicity. Various ligands for cancer cell specific markers have been uncovered and inspected for directional delivery of the anti-cancer drug to the tumor site, in addition to diagnostic applications. Over the past few decades research related to the ligand targeted therapy (LTT) increased tremendously aiming to treat various pathologies, mainly cancers with well exclusive markers. Malignant tumors are known to induce elevated levels of a variety of proteins and peptides known as cancer "markers" as certain antigens (e.g., Prostate specific membrane antigen "PSMA", carcinoembryonic antigen "CEA"), receptors (folate receptor, somatostatin receptor), integrins (Integrin αvβ3) and cluster of differentiation molecules (CD13). The choice of an appropriate marker to be targeted and the design of effective ligand-drug conjugate all has to be carefully selected to generate the required therapeutic effect. Moreover, since some tumors express aberrantly high levels of more than one marker, some approaches investigated targeting cancer cells with more than one ligand (dual or multi targeting). We aim in this review to report an update on the cancer-specific receptors and the vehicles to deliver cytotoxic drugs, including recent advancements on nano delivery systems and their implementation in targeted cancer therapy. We will discuss the advantages and limitations facing this approach and possible solutions to mitigate these obstacles. To achieve the said aim a literature search in electronic data bases (PubMed and others) using keywords "Cancer specific receptors, cancer specific antibody, tumor specific peptide carriers, cancer overexpressed proteins, gold nanotechnology and gold nanoparticles in cancer treatment" was carried out.

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.

Trastuzumab-induced cardiotoxicity: a review of clinical risk factors, pharmacologic prevention, and cardiotoxicity of other HER2-directed therapies

PURPOSE

Despite great success as a targeted breast cancer therapy, trastuzumab use may be complicated by heart failure and loss of left ventricular contractile function. This review summarizes the risk factors, imaging, and prevention of cardiotoxicity associated with trastuzumab and other HER2-targeted therapies.

FINDINGS

Cardiovascular disease risk factors, advanced age, and previous anthracycline treatment predispose to trastuzumab-induced cardiotoxicity (TIC), with anthracycline exposure being the most significant risk factor. Cardiac biomarkers such as troponins and pro-BNP and imaging assessments such as echocardiogram before and during trastuzumab therapy may help in early identification of TIC. Initiation of beta-adrenergic antagonists and angiotensin converting enzyme inhibitors may prevent TIC. Cardiotoxicity rates of other HER2-targeted treatments, such as pertuzumab, T-DM1, lapatinib, neratinib, tucatinib, trastuzumab deruxtecan, and margetuximab, appear to be significantly lower as reported in the pivotal trials which led to their approval.

CONCLUSIONS

Risk assessment for TIC should include cardiac imaging assessment and should incorporate prior anthracycline use, the strongest risk factor for TIC. Screening and prediction of cardiotoxicity, referral to a cardio-oncology specialist, and initiation of effective prophylactic therapy may all improve prognosis in patients receiving HER2-directed therapy. Beta blockers and ACE inhibitors appear to mitigate risk of TIC. Anthracycline-free regimens have been proven to be efficacious in early HER2-positive breast cancer and should now be considered the standard of care for early HER2-positive breast cancer. Newer HER2-directed therapies appear to have significantly lower cardiotoxicity compared to trastuzumab, but trials are needed in patients who have experienced TIC and patients with pre-existing cardiac dysfunction.

Conventional cardiac risk factors associated with trastuzumab-induced cardiotoxicity in breast cancer: Systematic review and meta-analysis

BACKGROUND

Trastuzumab has had a major impact on the treatment of human epidermal growth factor receptor 2 (HER2) positive breast cancer patients. However, it is associated with cardiotoxicity, expressed as an asymptomatic decrease in left ventricular ejection fraction (LVEF) and less often as clinical HF. The aim of this meta-analysis is to identify the association of conventional cardiovascular risk factors with the development of trastuzumab-induced cardiotoxicity (TIC).

METHODS

A literature search of PubMed was conducted to identify studies examining the association between cardiovascular risk factors and TIC. Data were extracted and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated examining the odds of developing TIC for each of the risk factors.

RESULTS

A total of 35 studies were included in the analysis. Age (OR:0.7; 95%CI 0.318-1.09; P= 0.0004), hypertension (OR:0.69; 95%CI 0.26-1.12; P = 0.001), smoking(OR:0.35; 95%CI 0.01- 0.69; P = 0.038), diabetes mellitus (OR:0.44; 95%CI 0.24- 0.68; P = 0.0001) and family history of CAD (OR:5.51, 95%CI 1.76-17.25; P< 0.00001)were significantly associated with the development of cardiotoxicity. Known history of CAD (OR: 3.72; 95%CI 2.11-6.57; P = 0.0005) was also associated with the development of TIC.

CONCLUSION(S)

Identifying women at risk for TIC have several important potential applications. Clinicians may decide to assess LVEF more frequently in patients at highest risk for TIC in order to detect LV systolic dysfunction earlier. Additionally, this could help identify patients who would benefit most from prophylactic therapy for preventing TIC.

Potential Successes and Challenges of Targeted Cancer Therapies

The concept and realization of targeted anticancer therapy (TAT) have existed for at least two decades and continue to expand rapidly. It has become clear that there is no "magic bullet" to cure cancer and that even TATs are unlikely to be successful as single agents, necessitating combination with chemotherapy, radiotherapy, or even other targeting agents. The other promise that has not been fulfilled by TAT is that of reduced toxicity. It was thought that by targeting receptors on or within cells, rather than particular phases of the cell cycle, TATs would not be toxic. However, it turns out that the targets also exist on or within normal cells and that there is even cross-reactivity between receptors on nontarget tissues. All of this results in toxicity, the mechanism of which are the same as the mechanism of action of the drugs, making toxicity reduction or prevention very difficult. This leads to new toxicities with new targeted treatments. Nevertheless, all of the above should not detract from the obvious successes of targeted agents, which have turned several acutely fatal cancers into chronic diseases and rendered some hitherto untreatable cancers into treatable diseases.

Early morphological changes in cardiac mitochondria after subcutaneous administration of trastuzumab in rabbits: possible prevention with oral selenium supplementation

Trastuzumab-mediated cardiotoxicity poses a significant challenge in the treatment of human epidermal growth factor receptor 2-positive breast cancer. To understand the underlying mechanisms, we conducted experiments to determine ultrastructural changes of rabbit cardiac tissue under different experimental conditions, including differing doses of trastuzumab and supplementation with oral sodium selenite, an antioxidant. Histopathology revealed lymphocyte and macrophage infiltration in myocardium of rabbits receiving four doses of trastuzumab. Transmission electron microscopy showed substantial changes with trastuzumab, including edema with separation of myofibril bundles and rupture of sarcomeres. Within mitochondria, edema resulted in disorganization of the cristae. Some mitochondria exhibited eccentric projections of their membranes with disruption of both inner and outer membranes. These changes were seen to a lesser extent in rabbits who received oral sodium selenite prior to trastuzumab. Selenium is integral to functioning of mitochondrial glutathione peroxidases, important antioxidants that also maintain membrane integrity. If mitochondria are disrupted as part of trastuzumab cardiac toxicity, selenium supplementation might be an important therapeutic or preventive consideration. Larger studies to explore this hypothesis are warranted.

Screening of differentially expressed genes and identification of NUF2 as a prognostic marker in breast cancer

The aims of the present study were to screen differentially expressed genes (DEGs) in breast cancer (BC) and investigate NDC80 kinetochore complex component (NUF2) as a prognostic marker of BC in detail. A total of four BC microarray datasets, downloaded from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases, were used to screen DEGs. A total of 190 DEGs with the same expression trends were identified in the 4 datasets, including 65 upregulated and 125 downregulated DEGs. Functional and pathway enrichment analyses were performed using the Database for Annotation, Visualization and Integrated Discovery. The upregulated DEGs were enriched for 10 Gene Ontology (GO) terms and 7 pathways, and the downregulated DEGs were enriched for 10 GO terms and 10 pathways. A protein‑protein interaction network containing 149 nodes and 930 edges was constructed using the Search Tool for the Retrieval of Interacting Genes, and 2 functional modules were identified using the MCODE plugin of Cytoscape. Based on an in‑depth analysis of module 1 and literature mining, NUF2 was selected for further research. Oncomine database analysis and reverse transcription‑quantitative PCR showed that NUF2 is significantly upregulated in BC tissues. In analyses of correlations between NUF2 and clinical pathological characteristics, NUF2 was significantly associated with the malignant features of BC. Using 5 additional datasets from GEO, it was demonstrated that NUF2 has a significant prognostic role in both ER‑positive and ER‑negative BC. A Gene Set Enrichment Analysis indicated that NUF2 may regulate breast carcinogenesis and progression via cell cycle‑related pathways. The results of the present study demonstrated that NUF2 is overexpressed in BC and is significantly associated with its multiple pathological features and prognosis.

Knockdown of lncRNA HOTAIR sensitizes breast cancer cells to ionizing radiation through activating miR-218

Radiotherapy is a major therapeutic strategy for breast cancer, while cancer radioresistance remains an obstacle for the successful control of the tumor. Novel radiosensitizing targets are to be developed to overcome radioresistance. Recently, long non-coding RNAs (lncRNAs) were proved to play critical roles in cancer progression. Among all, lncRNA HOTAIR was found to participate in cancer metastasis and chemoresistance. In the present study, we aimed to investigate the radiosensitizing effects of targeting HOTAIR and the underlying mechanism. Our data showed that HOTAIR (HOX antisense intergenic RNA) was up-regulated in breast cancer cells and tissues, and the expression of HOTAIR increased following irradiation. Knockdown of HOTAIR inhibited cell survival and increased cell apoptosis in response to ionizing radiation. Moreover, compared with control group, radiation induced more DNA damage and cell cycle arrest in HOTAIR knockdown cells. Finally, we found that the radiosentizing effects of HOTAIR were related to the up-regulation of miR-218, a ceRNA of HOTAIR. In conclusion, our finding showed that HOTAIR inhibition sensitizes breast cancer cells to ionizing radiation, induced severe DNA damage and activated apoptosis pathways, suggesting a possible role of HOTAIR as a novel target for breast cancer radiosensitization.

Sex-Specific Physiology and Cardiovascular Disease

Sex differences in cardiovascular diseases can be classified as those which are specific to one sex and those that differ in incidence, prevalence, etiology, symptomatology, response to treatment, morbidity, and mortality in one sex compared to the other. All sex differences in cardiovascular conditions have their basis in the combined expression of genetic and hormonal differences between women and men. This chapter addresses how understanding basic mechanisms of hormone responses, imaging diagnostics, and integration of genomics and proteomics has advanced diagnosis and improved outcomes for cardiovascular conditions, apart from those related to pregnancy that are more prevalent in women. These conditions include obstructive coronary artery disease, coronary microvascular dysfunction, spontaneous coronary artery dissection, diseases of the cardiac muscle including heart failure and takotsubo cardiomyopathy, and conditions related to neurovascular dysregulation including hot flashes and night sweats associated with menopause and effects of exogenous hormones on vascular function. Improvement in technologies allowing for noninvasive assessment of neuronally mediated vascular reactivity will further improve our understanding of the basic etiology of the neurovascular disorders. Consideration of sex, hormonal status, and pregnancy history in diagnosis and treatment protocols will improve prevention and outcomes of cardiovascular disease in women as they age.

Curing breast cancer and killing the heart: A novel model to explain elevated cardiovascular disease and mortality risk among women with early stage breast cancer

Due to advances in prevention, early detection and treatment, early breast cancer mortality has decreased by nearly 40% during the last four decades. Yet, the risk of cardiovascular disease (CVD) mortality is significantly elevated following a breast cancer diagnosis, and it is a leading cause of death in this population. This review will discuss the most recent evidence for risks, pathology, mechanisms, and prevention of CVD morbidity and mortality in women with breast cancer. This evidence will be synthesized into a new model 'the compounding risk and protection model.' This model proposes that the balance between risk factors (i.e., older age, pre-existing traditional CVD risk factors and shared biologic pathways for CVD and cancer such as inflammation, as well as treatment-related and lifestyle toxicity) and potential protection factors (i.e., lifelong non-smoking, regular physical activity, a healthy diet rich in fruits and vegetables, and management of body weight and stress, heart failure therapy) determine the individual risk of CVD morbidity and mortality after diagnosis of early breast cancer.

Monoclonal antibodies for the treatment of non-hematological tumors: a safety review

Introduction: The introduction of monoclonal antibodies (moAbs) into clinical practice revolutionized the treatment strategies in several solid tumors. These agents differ from cytotoxic chemotherapy for their mechanism of action and toxicity. By targeting specific antigens present on healthy cells and modulating immune system activity, these biological drugs are able to generate a wide spectrum of peculiar adverse events that can negatively impact on patients' quality of life. Areas covered: In this review, the main side effects associated with the use of moAbs have been described to show their incidence and current management strategies, which may drive clinicians in their daily practice. Expert opinion: The majority of these drugs represents an example of successful innovation, since they are able to induce a significant improvement of patients' survival and quality of life without any increase in related side effects as compared to standard cancer treatments. For this reason, they have become new milestones in personalized therapy for different non-hematological malignancies. With the increasing use of moAbs in treatment regimens, it is strongly recommended that clinicians are knowledgeable about the side effects associated with these agents, their management and monitoring, to optimize the clinical treatment of cancer patients.

Rotundic acid enhances the impact of radiological toxicity on MCF-7 cells through the ATM/p53 pathway

Although radiation therapy is a powerful anticancer modality, radiation- induced stress response and gene expression with adaptive resistance may severely compromise the effectiveness of radiation. The function of rotundic acid (RA) on inducing apoptosis in the human breast cancer cell line MCF-7 has been investigated in a previous study. In the present study, the combined effect of chemotherapy and radiotherapy on reducing side effects was examined. The results of an MTT assay revealed that radiation (0.5, 2 and 10 Gy) effectively inhibit MCF-7 cell viability in a dose-dependent manner, consistent with the effects of RA (2, 5 and 12.5 µM). Interestingly, a lower dose of radiation (1 Gy) combined with RA (5 µM) exhibited a greater inhibition efficiency compared with a high dose of radiation alone. Flow cytometry revealed that radiation combined with RA induced the apoptosis of MCF-7 cells. Using western blotting, it was demonstrated that radiation induced the expression of ataxia-telangiectasia mutated (ATM) and p53 protein, and that RA enhanced this effect. On examining the potential underlying mechanism, it was revealed that radiation and RA combined induce Bcl-2-associated X protein expression and cell apoptosis in MCF-7 cells. An ATM inhibitor was able to restore the effect of radiation and RA on inducing MCF-7 cell apoptosis. These results suggest that the ATM/p53 pathway directly participates in radiation and RA-induced apoptosis in MCF-7 cells. RA has the potential for development as a novel drug for the treatment of human breast cancer combined with radiation therapy, given that the combined side effects are reduced.

Breast cancer drug trastuzumab induces cardiac toxicity: evaluation of human epidermal growth factor receptor 2 as a potential diagnostic and prognostic marker

Breast cancer is one of the most prevalent forms of cancer in the United States and worldwide. Cancer occurs through the uncontrolled development of new abnormal cell growth. Clinicians and researchers strive to improve diagnostics and treatments in pursuit of remedying breast cancer, while limiting or removing any potential side effects that may arise. Unfortunately, traditional treatments, such as anthracyclines (i.e., doxorubicin), can damage the cardiovascular system. Recent strategies have utilized antibody-based compounds as singular treatments, or in conjunction with other treatments, with the aim to minimize side effects. The human epidermal growth factor receptor 2 (HER2) protein has been the target of numerous antibody-based breast cancer therapies, such as trastuzumab (TZM) and trastuzumab emtansine (T-DM1). This review will discuss the HER2 receptor as a diagnostic marker in targeting breast cancer using the therapeutic agents TZM and T-DM1, as well as discuss the induced cardiac toxicity following TZM and T-DM1 treatments.

Paip1 affects breast cancer cell growth and represents a novel prognostic biomarker

Polyadenylate-binding protein-interacting protein 1 (Paip1) regulates translational initiation. Increasing evidence suggests that Paip1 plays important roles in cancer development and progression. This study explored the role of Paip1 in breast cancer progression and evaluated its prognostic value. The cellular location of Paip1 protein was determined using immunofluorescence. Then, Paip1 protein expression was evaluated by immunohistochemical staining in 119 breast cancers and 40 normal breast tissues. The correlation between Paip1 expression and the clinicopathologic features of breast cancer was evaluated using the χ² test, and differences in survival curves were analyzed using log-rank tests. The role of Paip1 in breast cancer proliferation and cell cycle progression was identified by siRNA transfection. Paip1 was expressed mainly in the cytoplasm of cancer cells and tissues. Expression was observed in 60.5% of the breast cancers (72/119), which was significantly higher than in normal breast tissues (17.5%; 7/40). High expression of Paip1 protein was associated with high histologic grade, late clinical stage, and a low survival rate. Multivariate analysis indicated that Paip1 was an independent prognostic factor. Additionally, Paip1 depletion by RNAi significantly decreased cell proliferation and induced cell cycle arrest. In conclusion, our study demonstrated that Paip1 promotes the growth of breast cancers and could be a prognostic biomarker and therapeutic target.

Therapeutic potentials of short interfering RNAs

Short interfering RNA (siRNA) is one of the members of the family of RNA interference (RNAi). Coupled with the RNA-induced silencing complex (RISC), siRNA is able to trigger the cleavage of target RNAs which serve as a defensive system against pathogens. Meanwhile, siRNA in gene silencing opens a new avenue for the treatment of various diseases. SiRNA can effectively inhibit viral infection and replication and suppress tumorigenesis and various inflammation-associated diseases and cardiovascular diseases by inactivation of viral genes and downregulation of oncogene expression. Recently, endogenous siRNAs (endo-siRNAs) were discovered in the reproductive cells of animals which may be associated with regulation of cell division. Structural modification of siRNA enhances the delivery, specificity and efficacy and bioavailability to the target cells. There are at least five categories of siRNA delivery systems including viral vectors, lipid-based nanoparticles, peptide-based nanoparticles, polymer-based nanoparticles and inorganic small molecules like metal ions, silica and carbon. Sufficient preclinical and clinical studies supported that siRNA may be a potential medicine for targeted therapy of various diseases in the near future.

Biological agents in gastrointestinal cancers: adverse effects and their management

Biological therapy comprises agents that by virtue of their unique mechanisms of action, are able to specifically incite a response against or target malignant cells. They differ from conventional chemotherapy with regard to mechanisms of action, indications and side effect profile. Biologic agents have revolutionized therapy for a number of malignancies. In the setting of gastrointestinal (GI) malignancies, agents targeting vascular endothelial growth factor (VEGF), human epidermal growth factor receptor 2 (Her2/Neu) and epidermal growth factor receptor (EGFR) have proven to be invaluable additions to chemotherapy. However, these agents bring with them a set of side effects attributable to their unique mechanisms of action. The anti VEGF agents-bevacizumab, aflibercept and ramucirumab, can result in renal and vascular complications such as hypertension, arterial thrombotic events (ATE), proteinuria and GI perforations. The anti EGFR agents classically cause dermatological toxicities, in addition to hypomagnesemia, which can be dose limiting for patients. Trastuzumab, a monoclonal antibody that targets Her2/Neu, is known to cause cardiotoxicity, especially when used with anthracyclines. Use of immunotherapy agents such as nivolumab is associated with the development immune related adverse events (irAEs). The use of these agents is expected to increase over the next few years and it is crucial that patients and practitioners are aware of their adverse effects and current management strategies. This review highlights the adverse events associated with the use of biologic and immunologic therapies in GI cancers, their incidence and current management strategies.

Localisation Microscopy of Breast Epithelial ErbB-2 Receptors and Gap Junctions: Trafficking after γ-Irradiation, Neuregulin-1β, and Trastuzumab Application

In cancer, vulnerable breast epithelium malignance tendency correlates with number and activation of ErbB receptor tyrosine kinases. In the presented work, we observe ErbB receptors activated by irradiation-induced DNA injury or neuregulin-1β application, or alternatively, attenuated by a therapeutic antibody using high resolution fluorescence localization microscopy. The gap junction turnover coinciding with ErbB receptor activation and co-transport is simultaneously recorded. DNA injury caused by 4 Gray of 6 MeV photon γ-irradiation or alternatively neuregulin-1β application mobilized ErbB receptors in a nucleograde fashion—a process attenuated by trastuzumab antibody application. This was accompanied by increased receptor density, indicating packing into transport units. Factors mobilizing ErbB receptors also mobilized plasma membrane resident gap junction channels. The time course of ErbB receptor activation and gap junction mobilization recapitulates the time course of non-homologous end-joining DNA repair. We explain our findings under terms of DNA injury-induced membrane receptor tyrosine kinase activation and retrograde trafficking. In addition, we interpret the phenomenon of retrograde co-trafficking of gap junction connexons stimulated by ErbB receptor activation.

TNF-α sensitizes chemotherapy and radiotherapy against breast cancer cells

Purpose

Despite new developments in cancer therapy, chemotherapy and radiotherapy remain the cornerstone of breast cancer treatment. Therefore, finding ways to reduce the toxicity and increase sensitivity is particularly important. Tumor necrosis factor alpha (TNF-α) exerts multiple functions in cell proliferation, differentiation and apoptosis. In the present study, we investigated whether TNF-α could enhance the effect of chemotherapy and radiotherapy against breast cancer cells.

Methods

Cell growth was determined by MTT assay in vitro, and by using nude mouse tumor xenograft model in vivo. Cell cycle and apoptosis/necrosis were evaluated by flow cytometry. DNA damage was visualized by phospho-Histone H2A.X staining. mRNA expression was assessed by using real-time PCR. Protein expression was tested by Western blot assay.

Results

TNF-α strengthened the cytotoxicity of docetaxel, 5-FU and cisplatin against breast cancer cells both in vitro and in vivo. TNF-α activated NF-κB pathway and dependently up-regulated expressions of CyclinD1, CyclinD2, CyclinE, CDK2, CDK4 and CDK6, the key regulators participating in G1→S phase transition. As a result, TNF-α drove cells out of quiescent G0/G1 phase, entering vulnerable proliferating phases. Treatment of TNF-α brought more DNA damage after Cs¹³⁷-irradiation and strengthened G2/M and S phase cell cycle arrest induced by docetaxel and cisplatin respectively. Moreover, the up-regulation of RIP3 (a necroptosis marker) by 5-FU, and the activation of RIP3 by TNF-α, synergistically triggered necroptosis (programmed necrosis). Knockdown of RIP3 attenuated the synergetic effect of TNF-α and 5-FU.

Conclusion

TNF-α presented radiotherapy- and chemotherapy-sensitizing effects against breast cancer cells.

Long noncoding RNA linc-ITGB1 promotes cell migration and invasion in human breast cancer

Breast cancer is the most commonly diagnosed cancer and the leading cause of cancer-related death in women globally. Its high morbidity and mortality, as well as its elevated tendency to metastasize to other organs, warrant the urgency to find new biomarkers for breast cancer diagnosis and treatment. The specific roles of long noncoding RNA linc-ITGB1 on cell proliferation and metastasis in breast cancer were explored in this study. The expression of linc-ITGB1 was significantly upregulated in both clinical breast cancer tissues and cultured breast cancer cell lines. The linc-ITGB1 knockdown with specific short hairpin RNA (shRNA) decreased cell proliferation and colony formation in vitro. Tumor growth in vivo was also inhibited by linc-ITGB1 depletion. In addition, linc-ITGB1 depletion caused cell accumulation in the G0/G1 phase. Breast cancer cell lines with linc-ITGB1 depletion exhibited decreased migration and invasion abilities compared with the control cells. Furthermore, the linc-ITGB1 knockdown decreased the expression of mesenchymal markers N-cadherin and vimentin while increasing the expression of the epithelial marker E-cadherin. Key cell cycle regulators Cdc25C and Cyclin B1 were also decreased by the linc-ITGB1 knockdown. These data suggest that linc-ITGB1 promotes breast cancer progression by inducing cell cycle arrest and interrupting the epithelial-to-mesenchymal transition process.

Oligo-clonal nanobodies as an innovative targeting agent for cancer therapy: New biology and novel targeting systems

Variable heavy chain of HcAb (VHH), the smallest intact antibody fragment, possesses sub-nanomolar affinity to antigens. In spite of conventional antibodies, these fragments recognize concave and linear epitopes. VHHs are one the best weapon for targeted drug delivery in nanomedicine and biopharmaceutics. HER2 is overexpressed in 20-25% of breast and ovarian cancers. For many reasons, HER2 is a prominent target for drug delivery to breast tumor. In this study, we designed a robust prokaryotic expression system to express functional VHHs against HER2 receptor. This system showed high recombinant yields besides purified VHHs flow cytometry verified great capabilities of these molecules to pinpoint ecto-domain of HER2 receptor in MC4L2 HER2+ while insignificant non-specific binding to MC4L2 HER2-confirm nanobodies trivial cross-reaction. In the next step, we evaluated cooperative effect of four distinctive VHHs (oligoclonal VHHs) targeting different epitopes on HER2. As our result proved, using oligoclonal nanobodies as targeting moiety enhance targeting efficacy in comparison with monoclonal VHH.

Cardiac safety of simultaneous anti-HER2 and anthracycline therapy

A long established oncological dogma requires that trastuzumab should not be given in combination with anthracyclines due to excessive synergistic cardiac morbidity. However, trastuzumab has been recently granted a license in the neoadjuvant setting with concurrent anthracylines. We discuss the role of anti-HER2 agents in breast cancer and their associated toxicities. Anthracycline chemotherapies are a central component of most adjuvant and neoadjuvant breast cancer regimens. Cardiac toxicity due to anthracyclines is explored. Finally, in this article, we will discuss the evidence for concurrent administration of anthracyclines and HER2-targeted agents.

Serum biomarkers evaluation to predict chemotherapy-induced cardiotoxicity in breast cancer patients

Anti-neoplastic chemotherapy can determine various side effects, including cardiotoxicity, and no real guidelines for its early detection and management have been developed. The aim of this study is to find some plasmatic markers able to identify breast cancer patients that are at greater risk of developing cardiovascular complications during chemotherapy, in particular heart failure. A prospective study on 100 breast cancer patients with mean age of 66 years in adjuvant treatment with anthracyclines, taxanes, and trastuzumab was performed. Patients underwent cardiological examination before starting treatment (T0) and at 3 months (T1), 6 months (T2), and 1 year (T3) after treatment. Evaluation of serum cardiac markers and N-terminal pro-brain natriuretic peptide (NT-proBNP) was performed at T0, T1, T2, and T3, simultaneously to electrocardiogram and echocardiogram, showing a significant increase in NT-proBNP concentration (p > 0.0001) at T1, T2, and T3, before left ventricular ejection fraction decrease became evident. Human epidermal growth factor receptor 2 (HER2)-negative patients were more susceptible to mild hematological cardiotoxicity, while HER2-positive patients were more susceptible to severe cardiotoxicity. A significant correlation between NT-proBNP increased values after chemotherapy and prediction of mortality at 1 year was evidenced. From our experience, serum biomarker detection was able to support an early diagnosis of cardiac damage, also in the absence of left ventricular ejection fraction decrease. Therefore, the evaluation of specific plasmatic markers for cardiac damage is more sensitive than echocardiography in the early diagnosis of chemotherapy-related cardiotoxicity; furthermore, it can also add a prognostic value on outcome.