Anthracyclines as Topoisomerase II Poisons: From Early Studies to New Perspectives

SiRNA-mediated knockdown of TOP2B protects hiPSC-derived cardiomyocytes from doxorubicin-induced toxicity

AIMS

Doxorubicin (Dox) is a potent chemotherapeutic agent, but its use is limited by cardiotoxicity, primarily due to the disruption of Topoisomerase-2 beta (TOP2B) activity. Dexrazoxane (Dex), an FDA-approved cardioprotective drug, alleviates Dox-induced toxicity but lacks heart-specific targeting. This study investigates siRNA-mediated TOP2B knockdown as a more targeted strategy to protect cardiomyocytes from Dox-induced damage.

MATERIALS AND METHODS

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were treated with siRNA to knock down TOP2B and were then exposed to Dox. We compared the cardioprotective effects of siRNA-mediated knockdown to Dex treatment using cell viability, cell toxicity assay and electrophysiological evaluation was performed using a multielectrode array (MEA).

KEY FINDINGS

Our results demonstrate that TOP2B silencing significantly decreases apoptosis and improved cell viability, as compared to the Dex treatment. Additionally, electrophysiological assays using a Multielectrode Array (MEA) demonstrated enhanced contractility and conductivity in siRNA-treated hiPSC-CMs. Furthermore, transmission electron microscopy (TEM) data revealed that TOP2B knockdown preserves mitochondrial morphology and sarcomere structure, compared to Dox and Dex-treated groups.

SIGNIFICANCE

These findings suggest that siRNA-mediated TOP2B inhibition could provide a safer, more specific approach to mitigate Dox-induced cardiotoxicity.

DNA repair and the contribution to chemotherapy resistance

The DNA damage response comprises a set of imperfect pathways that maintain cell survival following exposure to DNA damaging agents. Cancers frequently exhibit DNA repair pathway alterations that contribute to their intrinsic genome instability. This, in part, facilitates a therapeutic window for many chemotherapeutic agents whose mechanisms of action often converge at the generation of a double-strand DNA break. The development of therapy resistance occurs through countless molecular mechanisms that promote tolerance to DNA damage, often by preventing break formation or increasing repair capacity. This review broadly discusses the DNA damaging mechanisms of action for different classes of chemotherapeutics, how avoidance and repair of double-strand breaks can promote resistance, and strategic directions for counteracting therapy resistance.

Understanding the Mechanisms of Chemotherapy-Related Cardiotoxicity Employing hiPSC-Derived Cardiomyocyte Models for Drug Screening and the Identification of Genetic and Epigenetic Variants

Chemotherapy-related cardiotoxicity (CTRTOX) is a profound and common side effect of cancer-based therapy in a subset of patients. The underlying factors and the associated mechanisms contributing to severe toxicity of the heart among these patients remain unknown. While challenges remain in accessing human subjects and their ventricular cardiomyocytes (CMs), advancements in human induced pluripotent stem cell (hiPSC)-technology-based CM differentiation protocols over the past few decades have paved the path for iPSC-based models of human cardiac diseases. Here, we offer a detailed analysis of the underlying mechanisms of CTRTOX. We also discuss the recent advances in therapeutic strategies in different animal models and clinical trials. Furthermore, we explore the prospects of iPSC-based models for identifying novel functional targets and developing safer chemotherapy regimens for cancer patients that may be beneficial for developing personalized cardioprotectants and their application in clinical practice.

The Application and Molecular Mechanisms of Mitochondria-Targeted Antioxidants in Chemotherapy-Induced Cardiac Injury

Chemotherapeutic agents play a crucial role in cancer treatment. However, their use is often associated with significant adverse effects, particularly cardiotoxicity. Drugs such as anthracyclines (e.g., doxorubicin) and platinum-based agents (e.g., cisplatin) cause mitochondrial damage, which is one of the main mechanisms underlying cardiotoxicity. These drugs induce oxidative stress, leading to an increase in reactive oxygen species (ROS), which in turn damage the mitochondria in cardiomyocytes, resulting in impaired cardiac function and heart failure. Mitochondria-targeted antioxidants (MTAs) have emerged as a promising cardioprotective strategy, offering a potential solution. These agents efficiently scavenge ROS within the mitochondria, protecting cardiomyocytes from oxidative damage. Recent studies have shown that MTAs, such as elamipretide, SkQ1, CoQ10, and melatonin, significantly mitigate chemotherapy-induced cardiotoxicity. These antioxidants not only reduce oxidative damage but also help maintain mitochondrial structure and function, stabilize mitochondrial membrane potential, and prevent excessive opening of the mitochondrial permeability transition pore, thus preventing apoptosis and cardiac dysfunction. In this review, we integrate recent findings to elucidate the mechanisms of chemotherapy-induced cardiotoxicity and highlight the substantial therapeutic potential of MTAs in reducing chemotherapy-induced heart damage. These agents are expected to offer safer and more effective treatment options for cancer patients in clinical practice.

Atomic Force Microscopy: A Versatile Tool in Cancer Research

The implementation of novel analytic methodologies in cancer and biomedical research has enabled the quantification of parameters that were previously disregarded only a few decades ago. A notable example of this paradigm shift is the widespread integration of atomic force microscopy (AFM) into biomedical laboratories, significantly advancing our understanding of cancer cell biology and treatment response. AFM allows for the meticulous monitoring of different parameters at the molecular and nanoscale levels, encompassing critical aspects such as cell morphology, roughness, adhesion, stiffness, and elasticity. These parameters can be systematically investigated in correlation with specific cell treatment, providing important insights into morpho-mechanical properties during normal and treated conditions. The resolution of this system holds the potential for its systematic adoption in clinics; its application could produce useful diagnostic information regarding the aggressiveness of cancer and the efficacy of treatment. This review endeavors to analyze the current literature, underscoring the pivotal role of AFM in biomedical research, especially in cancer cases, while also contemplating its prospective application in a clinical context.

Noncanonical inhibition of topoisomerase II alpha by oxidative stress metabolites

During its catalytic cycle, the homodimeric ATPase topoisomerase II alpha (TOP2A) cleaves double stranded DNA and remains covalently bound to 5' ends via tyrosine phosphodiester bonds. After passing a second, intact duplex through, TOP2A rejoins the break and releases from the DNA. Thereby, TOP2A can relieve strain accumulated during transcription, replication and chromatin remodeling and disentangle sister chromatids for mitosis. Chemotherapy agents such as etoposide are poisons that trap TOP2A mid-cycle, covalently bound to cleaved DNA, leaving behind DNA double strand breaks and activating DNA damage response. While etoposide has been proposed to stabilize the TOP2A-DNA cleavage complex (TOP2Acc) via interfacial inhibition, we have elucidated a complementary mechanism mediated by the ability of etoposide and other TOP2A poisons to induce oxidative stress. Consequently, lipid peroxidation and accumulation of lipid-derived electrophiles such as 4-hydroxynonenal (HNE) results in covalent modification of TOP2A, both blocking ATPase activity and trapping TOP2Acc. HNE modifies multiple sites on human TOP2A in vitro, including alkylating Cys216 in the ATPase domain in a DNA-dependent fashion. Taken together, our data suggest an underappreciated role for TOP2A as a redox sensor in tumor cells, connecting oxidative stress to DNA damage signaling and thereby creating a target for redox-active drugs.

Empagliflozin Dampens Doxorubicin-Induced Chemobrain in Rats: The Possible Involvement of Oxidative Stress and PI3K/Akt/mTOR/NF-κB/TNF-α Signaling Pathways

Chemobrain is a cognitive impairment observed in up to 75% of cancer patients treated with doxorubicin (DOX). Cognitive deficits associated with DOX are complex, and multiple interplay pathways contribute to memory impairment and the loss of concentration. Empagliflozin (EMPA), a sodium-glucose co-transporter-2 (SGLT-2) inhibitor with neuroprotective potential, has recently been elucidated because of its regulatory effects on oxidative stress and neuroinflammation. Thus, this study aimed to explore the protective mechanisms of EMPA in DOX-induced chemobrain. Rats were allocated to four groups: normal (NC), EMPA, DOX, and EMPA + DOX. Chemobrain was induced in the third and fourth groups by DOX (2 mg/kg, IP) on the 0th, 7th, 14th, and 21st days of the study, while EMPA was administered (10 mg/kg, PO) for 28 consecutive days in both the EMPA and EMPA + DOX groups. Behavioral and biochemical assessments were then performed. Rats treated with DOX exhibited significant memory, learning, and muscle coordination dysfunctions. Moreover, DOX boosted oxidative stress in the brain, as evidenced by elevated malondialdehyde (MDA) content together with decreased levels of nuclear factor-erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) and reduced glutathione (GSH). Neuroinflammation was also observed as an upsurge of tumor necrosis factor-alpha (TNF-α) and nuclear factor kappa B (NF-κB) (p65). Additionally, DOX diminished the expression of brain-derived neurotrophic factor (BDNF) and increased phosphoinositol-3-kinase (PI3K), phosphorylated-Akt (pAkt), and mammalian target of rapamycin (mTOR) content. EMPA exhibited potent neuroprotective potential in DOX-induced cognitive impairment, attributed to its antioxidant and neuroplasticity-enhancing properties and suppression of the PI3K/Akt/mTOR/NF-κB/TNF-α signaling pathway.

Quinalizarin induces autophagy, apoptosis and mitotic catastrophe in cervical and prostate cancer cells

Cancer diseases are a serious health problem for society, and among them cervical and prostate cancer rank high in terms of mortality. One of the reasons is the phenomenon of drug resistance and side effects accompanying conventional chemo- and radiotherapy. This requires continuous development of alternative treatment methods and searching for new compounds with anti-cancer potential. An example is quinalizarin, which was tested for its anti-cancer potential. The MTT test showed cytotoxic activity of quinalizarin against Hela and DU145 cell lines. Morphological analysis showed nuclear changes typical of apoptosis, which was confirmed by the annexin V/PE test, activation of caspases 3/7 and inhibition of Bcl-2 protein expression. Increased permeability of mitochondrial membranes and ROS generation were demonstrated. Inhibition of cell migration, blocking in the G0/G1 phase, increased number of cells with damaged DNA and an increase in markers of mitotic catastrophe, i.e. micro- and multinucleation including the presence of abnormal mitotic figures were also observed. At the same time, increased autophagy was observed, and preincubation of cells with chloroquine inhibited this process, which contributed to the increased cytotoxicity of quinalizarin towards the tested cells. Quinalizarin has a multidirectional effect based on apoptosis and alternative types of cell death.

Cardioprotection strategies for anthracycline cardiotoxicity

Thanks to the fantastic progress in cancer therapy options, there is a growing population of cancer survivors. This success has resulted in a need to focus much effort into improving the quality of life of this population. Cancer and cardiovascular disease share many common risk factors and have an interplay between them, with one condition mechanistically affecting the other and vice versa. Furthermore, widely prescribed cancer therapies have known toxic effects in the cardiovascular system. Anthracyclines are the paradigm of efficacious cancer therapy widely prescribed with a strong cardiotoxic potential. While some cancer therapies cardiovascular toxicities are transient, others are irreversible. There is a growing need to develop cardioprotective therapies that, when used in conjunction with cancer therapies, can prevent cardiovascular toxicity and thus improve long-term quality of life in survivors. The field has three main challenges: (i) identification of the ultimate mechanisms leading to cardiotoxicity to (ii) identify specific therapeutic targets, and (iii) more sensible diagnostic tools to early identify these conditions. In this review we will focus on the cardioprotective strategies tested and under investigation. We will focus this article into anthracycline cardiotoxicity since it is still the agent most widely prescribed, the one with higher toxic effects on the heart, and the most widely studied.

Anthracycline-induced cardiomyopathy: risk prediction, prevention and treatment

Anthracyclines are the cornerstone of treatment for many malignancies. However, anthracycline cardiotoxicity is a considerable concern given that it can compromise the clinical effectiveness of the treatment and patient survival despite early discontinuation of therapy or dose reduction. Patients with cancer receiving anthracycline treatment can have a reduction in their quality of life and likelihood of survival due to cardiotoxicity, irrespective of their oncological prognosis. Increasing knowledge about anthracycline cardiotoxicity has enabled the identification of patients who are candidates for anthracycline regimens and those who might develop anthracycline-induced cardiomyopathy. Anthracycline cardiotoxicity is a unique and evolving phenomenon that begins with myocardial cell damage, progresses to reduced left ventricular ejection fraction, and culminates in symptomatic heart failure if it is not promptly detected and treated. Early risk stratification can be guided by imaging or biomarkers. In this Review, we present a comprehensive and clinically useful approach to cardiomyopathy related to anthracycline therapy, encompassing its epidemiology, definition, mechanisms, novel classifications, risk factors and patient risk stratification, diagnostic approaches (including imaging and biomarkers), treatment guidelines algorithms, and the role of new cardioprotective drugs that are used for the treatment of heart failure.

Anthracyclines disaggregate and restore mutant p63 function: a potential therapeutic approach for AEC syndrome

Ankyloblepharon-Ectodermal Defects-Cleft Lip/Palate (AEC) syndrome is a rare genetic disorder caused by mutations in the TP63 gene, which encodes a transcription factor essential for epidermal gene expression. A key feature of AEC syndrome is chronic skin erosion, for which no effective treatment currently exists. Our previous studies demonstrated that mutations associated with AEC syndrome lead to p63 protein misfolding and aggregation, exerting a dominant-negative effect. By performing a high-throughput screening of epigenetic and FDA-approved compounds in a co-transfection model of wild-type and mutant p63, we found that two compounds, Doxorubicin and Epirubicin, alleviate protein aggregation and restore p63 transactivation function. Moreover, treatment with these compounds reduced protein aggregation and restored the expression of keratinocyte-specific p63 target genes in primary keratinocytes derived from a conditional ΔNp63αL514F knock-in AEC mouse model, which mimics the ectodermal defects and skin erosions characteristic of AEC syndrome. A chemical analog of Doxorubicin, diMe-Doxorubicin, which exhibits lower tissue and organ toxicity, was also found to be effective in promoting the disaggregation of mutant p63 and rescuing its transcriptional activity. Our findings identify compounds that can partially resolve mutant p63 aggregation, increase its monomeric isoform, and reactivate its transcriptional function. These results suggest potential therapeutic efficacy for treating skin erosions in AEC syndrome.

Emerging Role of Natural Topoisomerase Inhibitors as Anticancer agents

Topoisomerases I and II are the functionally two forms of DNA topoisomerase. In anticancer research, novel anticancer chemotherapeutical capable of blocking topoisomerase enzymes have been discovered. Most commonly, topoisomerase causes replication fork arrest and doublestrand breaks, and this is how a clinically successful topoisomerase-targeting anticancer medicines work. Unfortunately, this novel mechanism of action has been linked to the development of secondary malignancies as well as cardiotoxicity. The specific binding locations and mechanisms of topoisomerase poisons have been identified by studying the structures of topoisomerase-drug-DNA ternary complexes. Recent breakthroughs in science have revealed that isoform-specific human topoisomerase II poison could be created as safer anticancer drug molecules. It may also be able to develop catalytic inhibitors of topoisomerases by focusing on their inactive conformations. In addition to this, the discovery of new bacterial topoisomerase inhibitor molecules and regulatory proteins could lead to the discovery of new human topoisomerase inhibitors. As a result, biologists, organic chemists, and medicinal chemists worldwide have been identifying, designing, synthesizing, and testing a variety of novel topoisomerase-targeting bioactive compounds. This review focused on topoisomerase inhibitors, their mechanisms of action, and different types of topoisomerase inhibitors that have been developed during the last ten years.

Epidemiology, risk factors and mechanism of breast cancer and atrial fibrillation

Cancer and cardiovascular diseases are leading causes of death worldwide. Among them, breast cancer is one of the most common malignancies in women, while atrial fibrillation is one of the most extensively studied arrhythmias, with significant public health implications. As the global population ages and advancements in cancer treatments continue, the survival rates of breast cancer patients have significantly improved, leading to an increasing coexistence of breast cancer and atrial fibrillation. However, the mechanisms underlying this coexistence remain insufficiently studied, and there is no consensus on the optimal treatment strategies for these patients. This review consolidates existing research to systematically explore the epidemiological characteristics, risk factors, and pathophysiological mechanisms of both breast cancer and atrial fibrillation. It focuses on the unique signaling pathways associated with different molecular subtypes of breast cancer and their potential impact on the mechanisms of atrial fibrillation. Additionally, the relationship between atrial fibrillation treatment medications and breast cancer is discussed. These insights not only provide essential evidence for the precise prevention and management of atrial fibrillation in breast cancer patients but also lay a solid theoretical foundation for interdisciplinary clinical management practices.

Evolution of Theories on Doxorubicin-Induced Late Cardiotoxicity-Role of Topoisomerase

Doxorubicin (DOX) has been widely used as a cytotoxic chemotherapeutic. However, DOX has a number of side effects, such as myelotoxicity or gonadotoxicity, the most dangerous of which is cardiotoxicity. Cardiotoxicity can manifest as cardiac arrhythmias, myocarditis, and pericarditis; life-threatening late cardiotoxicity can result in heart failure months or years after the completion of chemotherapy. The development of late cardiomyopathy is not yet fully understood. The most important question is how DOX reprograms the cardiomyocyte, after which DOX is excreted from the body, initially without symptoms. However, clinically overt cardiomyopathy develops over the following months and years. Since the 1980s, DOX-induced disorders in cardiomyocytes have been thought to be related to oxidative stress and dependent on the Fe/reactive oxygen species (ROS) mechanism. That line of evidence was supported by dexrazoxane (DEX) protection, the only Food and Drug Administration (FDA)-approved drug for preventing DOX-induced cardiomyopathy, which complexes iron. Thus, the hypothesis related to Fe/ROS provides a plausible explanation for the induction of the development of late cardiomyopathy via DOX. However, in subsequent studies, DEX was used to identify another important mechanism in DOX-induced cardiomyopathy that is related to topoisomerase 2β (Top2β). Does the Top2β hypothesis explain the mechanisms of the development of DOX-dependent late heart failure? Several of these mechanisms have been identified to date, proving the involvement of Top2β in the regulation of the redox balance, including oxidative stress. Thus, the development of late cardiomyopathy can be explained based on mechanisms related to Top2β. In this review, we highlight free radical theory, iron imbalance, calcium overload, and finally, a theory based on Top2β.

Technologies for Targeted RNA Degradation and Induced RNA Decay

The vast majority of the human genome codes for RNA, but RNA-targeting therapeutics account for a small fraction of approved drugs. As such, there is great incentive to improve old and develop new approaches to RNA targeting. For many RNA targeting modalities, just binding is not sufficient to exert a therapeutic effect; thus, targeted RNA degradation and induced decay emerged as powerful approaches with a pronounced biological effect. This review covers the origins and advanced use cases of targeted RNA degrader technologies grouped by the nature of the targeting modality as well as by the mode of degradation. It covers both well-established methods and clinically successful platforms such as RNA interference, as well as emerging approaches such as recruitment of RNA quality control machinery, CRISPR, and direct targeted RNA degradation. We also share our thoughts on the biggest hurdles in this field, as well as possible ways to overcome them.

The Potential of Plant Polysaccharides and Chemotherapeutic Drug Combinations in the Suppression of Breast Cancer

Breast cancer is the most common cancer affecting women worldwide. The associated morbidity and mortality have been on the increase while available therapies for its treatment have not been totally effective. The most common treatment, chemotherapy, sometimes has dangerous side effects because of non-specific targeting, in addition to poor therapeutic indices, and high dose requirements. Consequently, agents with anticancer effects are being sought that can reduce the side effects induced by chemotherapy while increasing its cytotoxicity to cancer cells. This is possible using natural compounds that are safe and biologically active. There are many reports on plant polysaccharides due to their bioactive and anticancer properties. The use of plant polysaccharide together with a conventional cytotoxic drug may offer wide benefits in cancer therapy, producing synergistic effects, thereby reducing drug dose and, so, its associated side effects. In this review, we highlight an overview of the use of plant polysaccharides and chemotherapeutic drugs in breast cancer preclinical studies, including their mechanisms of anticancer activities. The findings emphasize the potential of plant polysaccharides to improve chemotherapeutic outcomes in breast cancer, paving the way for more effective and safer treatment strategies.

Impact of MTHFD2 Expression in Bladder/Breast Cancer and Screening of Its Potential Inhibitor

Genes of folate-mediated 1 carbon metabolism are found to be highly upregulated in tumor cells and promote cancer cell proliferation. The current study aimed to determine the expression of the MTHFD2 gene in bladder and breast cancers. Furthermore, the determination of potential ligand-based inhibitors against MTHFD2 was performed in comparison with those of chemotherapeutic drugs and natural plant-based compounds. Semiquantitative expression analysis along with structure-based virtual ligand library screening was done to find plausible inhibitors. MTHFD2 expression was significantly increased with tumor stage progression both in low- and high-grade bladder cancer and especially in triple-negative breast cancer. Virtual ligand-based library screening against the three-dimensional MTHFD2 protein structure led to the identification of plausible inhibitors like MCULE-8109969891-0 and MCULE-9715677418-0-1 that displayed lower binding free energy as compared to that of already documented LY345899. Similar scaffold commercial drugs leucal (LEU), epirubicin (EPI), and lometrexol also displayed strong binding to the active site of MTHFD2. EPI and LEU in combinatorial therapy were also tested in vitro on MDA-MB-231 cells. The high doses of LEU in combination with EPI showed a significant reduction in cell viability at 2 and 3 μM concentrations. The interaction of breast cancer serum with high expression of MTHFD2 also showed an increase in binding of epirubicin in the presence of leucovorin. The decrease in the absorbance spectra of epirubicin at 37 and 53 °C displayed the stability induced by LEU on the interaction of EPI with the MTHFD2 binding pocket. Leucovorin tends to stabilize the interaction as the binding affinity is high even at 53 °C. Thus, MTHFD2 might be used as a cancer biomarker since its expression level changes drastically with tumor progression. Further experimental studies are required to establish the potential mode of inhibition of the novel small ligands. Future in vivo trials may validate the effectiveness of the combinatorial therapy.

Elucidating the interplay of PPAR gamma inhibition and energy demand in adriamycin-induced cardiomyopathy: In Vitro and In Vivo perspective

Adriamycin is an anticancer anthracycline drug that inhibits the progression of topoisomerase II activity and causes apoptosis. The effective clinical application of the drug is very much limited by its adverse drug reactions on various tissues. Most importantly, Adriamycin causes cardiomyopathy, one of the life-threatening complications of the drug. Altered expression of PPARγ in adipocytes inhibited the glucose and fatty acids uptake by down regulating GLUT4 and CD36 expression and causes cardiotoxicity. Therefore, the influence of Adriamycin in cardiac ailments was investigated in vivo and in vitro. Adriamycin treated rats showed altered ECG profile, arrhythmic heartbeat with the elevated levels of CRP and LDH. Dysregulated lipid profiles with elevated levels of cholesterol and triglycerides were also observed. Possibilities of cardiac problems due to cardiomyopathy were analyzed through histopathology. Adriamycin treated rats showed no signs for atheromatous plaque formation in aorta but disorganized cardiomyocytes with myofibrillar loss and inflammation in heart tissue, indicative of cardiomyopathy. Reduced levels of antioxidant enzymes confirmed the incidence of oxidative stress. Adriamycin treatment significantly reduced glucose and insulin levels, creating energy demand due to decreased glucose and insulin levels with increased fatty acid accumulation, ultimately resulting in oxidative stress mediated cardiomyopathy. Since PPARs play a vital role in regulating oxidative stress, the effect of Adriamycin on PPARγ was analyzed by western blot. Adriamycin downregulated PPARγ in a dose-dependent manner in H9C2 cells in vitro. Overall, our study suggests that Adriamycin alters glucose and lipid metabolism via PPARγ inhibition that leads to oxidative stress and cardiomyopathy that necessitates a different therapeutic approach.

Nanotechnology Approaches for Prevention and Treatment of Chemotherapy-Induced Neurotoxicity, Neuropathy, and Cardiomyopathy in Breast and Ovarian Cancer Survivors

Nanotechnology has emerged as a promising approach for the targeted delivery of therapeutic agents while improving their efficacy and safety. As a result, nanomaterial development for the selective targeting of cancers, with the possibility of treating off-target, detrimental sequelae caused by chemotherapy, is an important area of research. Breast and ovarian cancer are among the most common cancer types in women, and chemotherapy is an essential treatment modality for these diseases. However, chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy are common side effects that can affect breast and ovarian cancer survivors quality of life. Therefore, there is an urgent need to develop effective prevention and treatment strategies for these adverse effects. Nanoparticles (NPs) have extreme potential for enhancing therapeutic efficacy but require continued research to elucidate beneficial interventions for women cancer survivors. In short, nanotechnology-based approaches have emerged as promising strategies for preventing and treating chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy. NP-based drug delivery systems and therapeutics have shown potential for reducing the side effects of chemotherapeutics while improving drug efficacy. In this article, the latest nanotechnology approaches and their potential for the prevention and treatment of chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy in breast and ovarian cancer survivors are discussed.

Harnessing the nutriceutics in early-stage breast cancer: mechanisms, combinational therapy, and drug delivery

BACKGROUND

Breast cancer (BC) is a significant health challenge, ranking as the second leading cause of cancer-related death and the primary cause of mortality among women aged 45 to 55. Early detection is crucial for optimal prognosis. Among various treatment options available for cancer, chemotherapy remains the predominant approach. However, its patient-friendliness is hindered by cytotoxicity, adverse effects, multi-drug resistance, potential for recurrence, and high costs. This review explores extensively studied phytomolecules, elucidating their molecular mechanisms. It also emphasizes the importance of combination therapy, highlighting recent advancements in the exploration of diverse drug delivery systems and novel routes of administration. The regulatory considerations are crucial in translating these approaches into clinical practices.

RESULTS

Consequently, there is growing interest in exploring the relationship between diet, cancer, and complementary and alternative medicine (CAM) in cancer chemotherapy. Phytochemicals like berberine, curcumin, quercetin, lycopene, sulforaphane, resveratrol, epigallocatechin gallate, apigenin, genistein, thymoquinone have emerged as promising candidates due to their pleiotropic actions on target cells through multiple mechanisms with minimal toxicity effects. This review focuses on extensively studied phytomolecules, elucidating their molecular mechanisms. It also emphasizes the importance of combination therapy, highlighting recent advancements in the exploration of diverse drug delivery systems and novel routes of administration. The regulatory considerations are crucial in translating these approaches into clinical practices.

CONCLUSION

The present review provides a comprehensive understanding of the molecular mechanisms, coupled with well-designed clinical trials and adherence to regulatory guidelines, which pave the way for nutrition-based combination therapies to become a frontline approach in early-stage BC treatment.

The significance of the apelinergic system in doxorubicin-induced cardiotoxicity

Cancer is the leading cause of death worldwide, and the number of cancer-related deaths is expected to increase. Common types of cancer include skin, breast, lung, prostate, and colorectal cancers. While clinical research has improved cancer therapies, these treatments often come with significant side effects such as chronic fatigue, hair loss, and nausea. In addition, cancer treatments can cause long-term cardiovascular complications. Doxorubicin (DOX) therapy is one example, which can lead to decreased left ventricle (LV) echocardiography (ECHO) parameters, increased oxidative stress in cellular level, and even cardiac fibrosis. The apelinergic system, specifically apelin and its receptor, together, has shown properties that could potentially protect the heart and mitigate the damages caused by DOX anti-cancer treatment. Studies have suggested that stimulating the apelinergic system may have therapeutic benefits for heart damage induced by DOX. Further research in chronic preclinical models is needed to confirm this hypothesis and understand the mechanism of action for the apelinergic system. This review aims to collect and present data on the effects of the apelinergic system on doxorubicin-induced cardiotoxicity.

Emerging role of immunogenic cell death in cancer immunotherapy: Advancing next-generation CAR-T cell immunotherapy by combination

Immunogenic cell death (ICD) is a stress-driven form of regulated cell death (RCD) in which dying tumor cells' specific signaling pathways are activated to release damage-associated molecular patterns (DAMPs), leading to the robust anti-tumor immune response as well as a reversal of the tumor immune microenvironment from "cold" to "hot". Chimeric antigen receptor (CAR)-T cell therapy, as a landmark in anti-tumor immunotherapy, plays a formidable role in hematologic malignancies but falls short in solid tumors. The Gordian knot of CAR-T cells for solid tumors includes but is not limited to, tumor antigen heterogeneity or absence, physical and immune barriers of tumors. The combination of ICD induction therapy and CAR-T cell immunotherapy is expected to promote the intensive use of CAR-T cell in solid tumors. In this review, we summarize the characteristics of ICD, stress-responsive mechanism, and the synergistic effect of various ICD-based therapies with CAR-T cells to effectively improve anti-tumor capacity.

Inhibition of topoisomerase 2 catalytic activity impacts the integrity of heterochromatin and repetitive DNA and leads to interlinks between clustered repeats

DNA replication and transcription generate DNA supercoiling, which can cause topological stress and intertwining of daughter chromatin fibers, posing challenges to the completion of DNA replication and chromosome segregation. Type II topoisomerases (Top2s) are enzymes that relieve DNA supercoiling and decatenate braided sister chromatids. How Top2 complexes deal with the topological challenges in different chromatin contexts, and whether all chromosomal contexts are subjected equally to torsional stress and require Top2 activity is unknown. Here we show that catalytic inhibition of the Top2 complex in interphase has a profound effect on the stability of heterochromatin and repetitive DNA elements. Mechanistically, we find that catalytically inactive Top2 is trapped around heterochromatin leading to DNA breaks and unresolved catenates, which necessitate the recruitment of the structure specific endonuclease, Ercc1-XPF, in an SLX4- and SUMO-dependent manner. Our data are consistent with a model in which Top2 complex resolves not only catenates between sister chromatids but also inter-chromosomal catenates between clustered repetitive elements.

Intracellular cartilage oligomeric matrix protein augments breast cancer resistance to chemotherapy

Chemotherapy persists as the primary intervention for breast cancer, with chemoresistance posing the principal obstacle to successful treatment. Herein, we show that cartilage oligomeric matrix protein (COMP) expression leads to increased cancer cell survival and attenuated apoptosis under treatment with several chemotherapeutic drugs, anti-HER2 targeted treatment, and endocrine therapy in several breast cancer cell lines tested. The COMP-induced chemoresistance was independent of the breast cancer subtype. Extracellularly delivered recombinant COMP failed to rescue cells from apoptosis while endoplasmic reticulum (ER)-restricted COMP-KDEL conferred resistance to apoptosis, consistent with the localization of COMP in the ER, where it interacted with calpain. Calpain activation was reduced in COMP-expressing cells and maintained at a lower level of activation during treatment with epirubicin. Moreover, the downstream caspases of calpain, caspases -9, -7, and -3, exhibited significantly reduced activation in COMP-expressing cells under chemotherapy treatment. Chemotherapy, when combined with calpain activators, rendered the cells expressing COMP more chemosensitive. Also, the anti-apoptotic proteins phospho-Bcl2 and survivin were increased in COMP-expressing cells upon chemotherapy. Cells expressing a mutant COMP lacking thrombospondin repeats exhibited reduced chemoresistance compared to cells expressing full-length COMP. Evaluation of calcium levels in the ER, cytosol, and mitochondria revealed that COMP expression modulates intracellular calcium homeostasis. Furthermore, patients undergoing chemotherapy or endocrine therapy demonstrated significantly reduced overall survival time when tumors expressed high levels of COMP. This study identifies a novel role of COMP in chemoresistance and calpain inactivation in breast cancer, a discovery with potential implications for anti-cancer therapy.

ARID1A is involved in DNA double-strand break repair in gastric cancer

Background

Defects in DNA damage repair can cause genetic mutations, which in turn can cause different types of cancers. Chromatin remodeling complexes, which help repair damaged DNA, can cause the chromatin structure to change as a result of DNA damage. ARID1A may play a role in the process of DNA damage repair, and arid1a may be related to the occurrence and development of gastric cancer (GC). This study aimed to investigate the mechanism of ARID1A regulating the DNA damage repair of gastric adenocarcinoma cell lines AGS and SGC-7901 and its effect on migration, proliferation and apoptosis.

Methods

The expression of ARID1A plasmid was detected by Western blot and real-time polymerase chain reaction (PCR). The effect of etoposide (ETO) on the survival rate of AGS and SGC-7901 gastric adenocarcinoma cell lines was detected by MTT assay. The DNA double-strand break model was established by ETO and then passed through the comet assay and immunofluorescence co-localization to observe DNA damage; western blot method was used to detect the effect of ARID1A on the expression of related proteins in DNA damage repair pathway in gastric adenocarcinoma cells; scratch test and colony formation experiments were used to observe ARID1A migration and proliferation of gastric adenocarcinoma cells. The flow cytometry was used to detect the effect of ARID1A on apoptosis of gastric adenocarcinoma cells.

Results

The expression of mRNA and protein was increased after transfection of ARID1A plasmid. ETO was confirmed by MTT assay to inhibit cell survival in a dose-dependent manner. After the DNA double-strand break model was established by ETO, the expression levels of phospho-ataxia telangiectasia mutated (p-ATM) protein increased in the overexpressed ARID1A group. Meanwhile, the overexpressed ARID1A group had a shortened tail moment, and γ-H2AX and ARID1A co-localized in the DNA damage site of the nucleus. The over-expressed ARID1A group had weaker wound healing ability, reduced number of clone formation, and increased apoptosis rate.

Conclusions

ARID1A may repair DNA double-strand breaks caused by ETO by p-ATM pathway; ARID1A can inhibit the migration and proliferation of gastric adenocarcinoma cells and promote apoptosis. Our findings indicate that ARID1A could serve as a therapeutic target and biomarker for GC patients.

Identification of hub genes and pathways in hepatitis B virus-associated hepatocellular carcinoma: A comprehensive in silico study

Background and Aim

The hepatitis B virus (HBV) is one of the most common causes of liver cancer in the world. This study aims to provide a better understanding of the mechanisms involved in the development and progression of HBV-associated hepatocellular carcinoma (HCC) by identifying hub genes and the pathways related to their functions.

Methods

GSE83148 and GSE94660 were selected from the Gene Expression Omnibus (GEO) database, differentially expressed genes (DEGs) with an adjusted p-value < 0.05 and a |logFC| ≥1 were identified. Common DEGs of two data sets were identified using the GEO2R tool. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene ontology (GO) databases were used to identify pathways. Protein-protein interactions (PPIs) analysis was performed by using the Cytoscap and Gephi. A Gene Expression Profiling Interactive Analysis (GEPIA) analysis was carried out to confirm the target genes.

Results

One hundred and ninety-eight common DEGs and 49 hub genes have been identified through the use of GEO and PPI, respectively. The GO and KEGG pathways analysis showed DEGs were enriched in the G1/S transition of cell cycle mitotic, cell cycle, spindle, and extracellular matrix structural constituent. The expression of four genes (TOP2A, CDK1, CCNA2, and CCNB2) with high scores in module 1 were more in tumor samples and have been identified by GEPIA analysis.

Conclusion

In this study, the hub genes and their related pathways involved in the development of HBV-associated HCC were identified. These genes, as potential diagnostic biomarkers, may provide a potent opportunity to detect HBV-associated HCC at the earliest stages, resulting in a more effective treatment.

Molecular choreography: Unveiling the dynamic landscape of type IIA DNA topoisomerases before T-segment passage through all-atom simulations

Type IIA DNA topoisomerases are molecular nanomachines responsible for controlling topological states of DNA molecules. Here, we explore the dynamic landscape of yeast topoisomerase IIA during key stages of its catalytic cycle, focusing in particular on the events preceding the passage of the T-segment. To this end, we generated six configurations of fully catalytic yeast topo IIA, strategically inserted a T-segment into the N-gate in relevant configurations, and performed all-atom simulations. The essential motion of topo IIA protein dimer was characterized by rotational gyrating-like movement together with sliding motion within the DNA-gate. Both appear to be inherent properties of the enzyme and an inbuilt feature that allows passage of the T-segment through the cleaved G-segment. Coupled dynamics of the N-gate and DNA-gate residues may be particularly important for controlled and smooth passage of the T-segment and consequently the prevention of DNA double-strand breaks. QTK loop residue Lys367, which interacts with ATP and ADP molecules, is involved in regulating the size and stability of the N-gate. The unveiled features of the simulated configurations provide insights into the catalytic cycle of type IIA topoisomerases and elucidate the molecular choreography governing their ability to modulate the topological states of DNA topology.

Clinical application of immunogenic cell death inducers in cancer immunotherapy: turning cold tumors hot

Immunotherapy has emerged as a promising cancer treatment option in recent years. In immune "hot" tumors, characterized by abundant immune cell infiltration, immunotherapy can improve patients' prognosis by activating the function of immune cells. By contrast, immune "cold" tumors are often less sensitive to immunotherapy owing to low immunogenicity of tumor cells, an immune inhibitory tumor microenvironment, and a series of immune-escape mechanisms. Immunogenic cell death (ICD) is a promising cellular process to facilitate the transformation of immune "cold" tumors to immune "hot" tumors by eliciting innate and adaptive immune responses through the release of (or exposure to) damage-related molecular patterns. Accumulating evidence suggests that various traditional therapies can induce ICD, including chemotherapy, targeted therapy, radiotherapy, and photodynamic therapy. In this review, we summarize the biological mechanisms and hallmarks of ICD and introduce some newly discovered and technologically innovative inducers that activate the immune system at the molecular level. Furthermore, we also discuss the clinical applications of combing ICD inducers with cancer immunotherapy. This review will provide valuable insights into the future development of ICD-related combination therapeutics and potential management for "cold" tumors.

Bifunctional iRGD-Exo-DOX crosses the blood-brain barrier to target central nervous system lymphoma

Central nervous system lymphoma (CNSL) is a type of hematological tumor. Treatment of CNSL is difficult due to the existence of the blood-brain barrier (BBB). Here, we used exosomes (Exos), a type of extracellular vesicle, and iRGD to construct a new drug carrier system and use it to load doxorubicin (DOX). The results of in vitro and in vivo experiments showed that the iRGD-Exo-DOX system can efficiently and securely transport DOX through the BBB and target tumor cells. The results suggest that iRGD-Exo-DOX may cross the BBB through brain microvascular endothelial cell-mediated endocytosis. Together, our study indicates an impactful treatment of central nervous system tumors.

Cardiomyocytes, cardiac endothelial cells and fibroblasts contribute to anthracycline-induced cardiac injury through RAS-homologous small GTPases RAC1 and CDC42

The clinical use of the DNA damaging anticancer drug doxorubicin (DOX) is limited by irreversible cardiotoxicity, which depends on the cumulative dose. The RAS-homologous (RHO) small GTPase RAC1 contributes to DOX-induced DNA damage formation and cardiotoxicity. However, the pathophysiological relevance of other RHO GTPases than RAC1 and different cardiac cell types (i.e., cardiomyocytes, non-cardiomyocytes) for DOX-triggered cardiac damage is unclear. Employing diverse in vitro and in vivo models, we comparatively investigated the level of DOX-induced DNA damage in cardiomyocytes versus non-cardiomyocytes (endothelial cells and fibroblasts), in the presence or absence of selected RHO GTPase inhibitors. Non-cardiomyocytes exhibited the highest number of DOX-induced DNA double-strand breaks (DSB), which were efficiently repaired in vitro. By contrast, rather low levels of DSB were formed in cardiomyocytes, which however remained largely unrepaired. Moreover, DOX-induced apoptosis was detected only in non-cardiomyocytes but not in cardiomyocytes. Pharmacological inhibitors of RAC1 and CDC42 most efficiently attenuated DOX-induced DNA damage in all cell types examined in vitro. Consistently, immunohistochemical analyses revealed that the RAC1 inhibitor NSC23766 and the pan-RHO GTPase inhibitor lovastatin reduced the level of DOX-induced residual DNA damage in both cardiomyocytes and non-cardiomyocytes in vivo. Overall, we conclude that endothelial cells, fibroblasts and cardiomyocytes contribute to the pathophysiology of DOX-induced cardiotoxicity, with RAC1- and CDC42-regulated signaling pathways being especially relevant for DOX-stimulated DSB formation and DNA damage response (DDR) activation. Hence, we suggest dual targeting of RAC1/CDC42-dependent mechanisms in multiple cardiac cell types to mitigate DNA damage-dependent cardiac injury evoked by DOX-based anticancer therapy.

Enhancing the Bioavailability of Resveratrol: Combine It, Derivatize It, or Encapsulate It?

Overcoming the limited bioavailability and extensive metabolism of effective in vitro drugs remains a challenge that limits the translation of promising drugs into clinical trials. Resveratrol, despite its well-reported therapeutic benefits, is not metabolically stable and thus has not been utilized as an effective clinical drug. This is because it needs to be consumed in large amounts to overcome the burdens of bioavailability and conversion into less effective metabolites. Herein, we summarize the more relevant approaches to modify resveratrol, aiming to increase its biological and therapeutic efficacy. We discuss combination therapies, derivatization, and the use of resveratrol nanoparticles. Interestingly, the combination of resveratrol with established chemotherapeutic drugs has shown promising therapeutic effects on colon cancer (with oxaliplatin), liver cancer (with cisplatin, 5-FU), and gastric cancer (with doxorubicin). On the other hand, derivatizing resveratrol, including hydroxylation, amination, amidation, imidation, methoxylation, prenylation, halogenation, glycosylation, and oligomerization, differentially modifies its bioavailability and could be used for preferential therapeutic outcomes. Moreover, the encapsulation of resveratrol allows its trapping within different forms of shells for targeted therapy. Depending on the nanoparticle used, it can enhance its solubility and absorption, increasing its bioavailability and efficacy. These include polymers, metals, solid lipids, and other nanoparticles that have shown promising preclinical results, adding more "hype" to the research on resveratrol. This review provides a platform to compare the different approaches to allow directed research into better treatment options with resveratrol.

Quantitative imaging of doxorubicin diffusion and cellular uptake in biomimetic gels with human liver tumor cells

Novel tumor-on-a-chip approaches are increasingly used to investigate tumor progression and potential treatment options. To improve the effect of any cancer treatment it is important to have an in depth understanding of drug diffusion, penetration through the tumor extracellular matrix and cellular uptake. In this study, we have developed a miniaturized chip where drug diffusion and cellular uptake in different hydrogel environments can be quantified at high resolution using live imaging. Diffusion of doxorubicin was reduced in a biomimetic hydrogel mimicking tissue properties of cirrhotic liver and early stage hepatocellular carcinoma (373 ± 108 µm2/s) as compared to an agarose gel (501 ± 77 µm2/s, p = 0.019). The diffusion was further lowered to 256 ± 30 µm2/s (p = 0.028) by preparing the biomimetic gel in cell media instead of phosphate buffered saline. The addition of liver tumor cells (Huh7 or HepG2) to the gel, at two different densities, did not significantly influence drug diffusion. Clinically relevant and quantifiable doxorubicin concentration gradients (1-20 µM) were established in the chip within one hour. Intracellular increases in doxorubicin fluorescence correlated with decreasing fluorescence of the DNA-binding stain Hoechst 33342 and based on the quantified intracellular uptake of doxorubicin an apparent cell permeability (9.00 ± 0.74 × 10-4 µm/s for HepG2) was determined. Finally, the data derived from the in vitro model were applied to a spatio-temporal tissue concentration model to evaluate the potential clinical impact of a cirrhotic extracellular matrix on doxorubicin diffusion and tumor cell uptake.

A Comprehensive Overview on Chemotherapy-Induced Cardiotoxicity: Insights into the Underlying Inflammatory and Oxidative Mechanisms

While oncotherapy has made rapid progress in recent years, side effects of anti-cancer drugs and treatments have also come to the fore. These side effects include cardiotoxicity, which can cause irreversible cardiac damages with long-term morbidity and mortality. Despite the continuous in-depth research on anti-cancer drugs, an improved knowledge of the underlying mechanisms of cardiotoxicity are necessary for early detection and management of cardiac risk. Although most reviews focus on the cardiotoxic effect of a specific individual chemotherapeutic agent, the aim of our review is to provide comprehensive insight into various agents that induced cardiotoxicity and their underlying mechanisms. Characterization of these mechanisms are underpinned by research on animal models and clinical studies. In order to gain insight into these complex mechanisms, we emphasize the role of inflammatory processes and oxidative stress on chemotherapy-induced cardiac changes. A better understanding and identification of the interplay between chemotherapy and inflammatory/oxidative processes hold some promise to prevent or at least mitigate cardiotoxicity-associated morbidity and mortality among cancer survivors.

Doxorubicin conjugates: a practical approach for its cardiotoxicity alleviation

INTRODUCTION

Doxorubicin (DOX) emerges as a cornerstone in the arsenal of potent chemotherapeutic agents. Yet, the clinical deployment of DOX is tarnished by its proclivity to induce severe cardiotoxic effects, culminating in heart failure and other consequential morbidities. In response, a panoply of strategies has undergone rigorous exploration over recent decades, all aimed at attenuating DOX's cardiotoxic impact. The advent of encapsulating DOX within lipidic or polymeric nanocarriers has yielded a dual triumph, augmenting DOX's therapeutic efficacy while mitigating its deleterious side effects.

AREAS COVERED

Recent strides have spotlighted the emergence of DOX conjugates as particularly auspicious avenues for ameliorating DOX-induced cardiotoxicity. These conjugates entail the fusion of DOX through physical or chemical bonds with diminutive natural or synthetic moieties, polymers, biomolecules, and nanoparticles. This spectrum encompasses interventions that impinge upon DOX's cardiotoxic mechanism, modulate cellular uptake and localization, confer antioxidative properties, or refine cellular targeting.

EXPERT OPINION

The endorsement of DOX conjugates as a compelling stratagem to mitigate DOX-induced cardiotoxicity resounds from this exegesis, amplifying safety margins and the therapeutic profile of this venerated chemotherapeutic agent. Within this ambit, DOX conjugates stand as a beacon of promise in the perpetual pursuit of refining chemotherapy-induced cardiac compromise.

In vitro evaluation of the reductive carbonyl idarubicin metabolism to evaluate inhibitors of the formation of cardiotoxic idarubicinol via carbonyl and aldo-keto reductases

The most important dose-limiting factor of the anthracycline idarubicin is the high risk of cardiotoxicity, in which the secondary alcohol metabolite idarubicinol plays an important role. It is not yet clear which enzymes are most important for the formation of idarubicinol and which inhibitors might be suitable to suppress this metabolic step and thus would be promising concomitant drugs to reduce idarubicin-associated cardiotoxicity. We, therefore, established and validated a mass spectrometry method for intracellular quantification of idarubicin and idarubicinol and investigated idarubicinol formation in different cell lines and its inhibition by known inhibitors of the aldo-keto reductases AKR1A1, AKR1B1, and AKR1C3 and the carbonyl reductases CBR1/3. The enzyme expression pattern differed among the cell lines with dominant expression of CBR1/3 in HEK293 and MCF-7 and very high expression of AKR1C3 in HepG2 cells. In HEK293 and MCF-7 cells, menadione was the most potent inhibitor (IC50 = 1.6 and 9.8 µM), while in HepG2 cells, ranirestat was most potent (IC50 = 0.4 µM), suggesting that ranirestat is not a selective AKR1B1 inhibitor, but also an AKR1C3 inhibitor. Over-expression of AKR1C3 verified the importance of AKR1C3 for idarubicinol formation and showed that ranirestat is also a potent inhibitor of this enzyme. Taken together, our study underlines the importance of AKR1C3 and CBR1 for the reduction of idarubicin and identifies potent inhibitors of metabolic formation of the cardiotoxic idarubicinol, which should now be tested in vivo to evaluate whether such combinations can increase the cardiac safety of idarubicin therapies while preserving its efficacy.

The Bisdioxopiperazine ICRF-193 Attenuates LPS-induced IL-1β Secretion by Macrophages

Inhibiting pathological secretion of Interleukin-1β has shown beneficial effects in disease models and in the clinic and thus there is interest in finding inhibitors that can reduce its release from macrophages in response to their activation by foreign pathogens. We used an in vitro human macrophage model to investigate whether ICRF-193, a Topoisomerase II inhibitor could modulate IL1B mRNA expression and IL-1β secretion. These macrophage-like cells readily secrete IL-1β in response to Lipopolysaccharide (LPS). Upon exposure to a non-toxic dose of ICRF-193, IL-1β secretion was diminished by ~ 40%; however, level of transcription of IL1B was unaffected. We show that there was no Topoisomerase 2B (TOP2B) binding to several IL1B gene sites, which may explain why ICRF-193 does not alter IL1B mRNA levels. Hence, we show for the first time that ICRF-193 can reduce IL-1β secretion. Its low cost and the development of water-soluble prodrugs of ICRF-193 warrants its further investigation in the modulation of pathological secretion of this cytokine for the treatment of inflammatory disorders. (165 words).

The cardio-oncology continuum: Bridging the gap between cancer and cardiovascular care

Cancer and cardiovascular disease are two of the leading causes of death worldwide. Although cancer has historically been viewed as a condition characterized by abnormal cell growth and proliferation, it is now recognized that cancer can lead to a variety of cardiovascular diseases. This is due to the direct impact of cancer on the heart and blood vessels, which can cause myocarditis, pericarditis, and vasculitis. Additionally, cancer patients frequently experience systemic effects such as oxidative stress, inflammation, and metabolic dysregulation, which can contribute to the development of cardiovascular risk factors such as hypertension, dyslipidemia, and insulin resistance. It is important to closely monitor patients with cancer, especially those undergoing chemotherapy or radiation therapy, for cardiovascular risk factors and promptly address them. This article aims to explore the clinical implications of the underlying mechanisms connecting cancer and cardiovascular diseases. Our analysis highlights the need for improved cooperation between oncologists and cardiologists, and specialized treatment for cancer survivors.

Locally Advanced Adenoid Cystic Carcinoma of the Breast-A Case Report with a Review of the Literature

Breast cancer (BC) is a heterogeneous disease distinguished by four main subtypes based on the expression of estrogen, progesterone receptors, and human epidermal growth factor-2 on the cancer cells. Triple-negative breast cancer (TNBC) consists of approximately 10-20% of all BCs and is characterized by a poor prognosis. Adenoid cystic carcinoma (ACC) of the breast is a rare, special type of TNBC with low metastatic potential and usually favorable prognosis. There are no established recommendations concerning systemic therapy in advanced ACC. We present a case of a 70-year-old woman with locally advanced ACC with progression after radical mastectomy, and review the literature concerning the treatment of metastatic disease focused on systemic therapy.

Prospects of Topoisomerase Inhibitors as Promising Anti-Cancer Agents

Topoisomerases are very important enzymes that regulate DNA topology and are vital for biological actions like DNA replication, transcription, and repair. The emergence and spread of cancer has been intimately associated with topoisomerase dysregulation. Topoisomerase inhibitors have consequently become potential anti-cancer medications because of their ability to obstruct the normal function of these enzymes, which leads to DNA damage and subsequently causes cell death. This review emphasizes the importance of topoisomerase inhibitors as marketed, clinical and preclinical anti-cancer medications. In the present review, various types of topoisomerase inhibitors and their mechanisms of action have been discussed. Topoisomerase I inhibitors, which include irinotecan and topotecan, are agents that interact with the DNA-topoisomerase I complex and avert resealing of the DNA. The accretion of DNA breaks leads to the inhibition of DNA replication and cell death. On the other hand, topoisomerase II inhibitors like etoposide and teniposide, function by cleaving the DNA-topoisomerase II complex thereby effectively impeding the release of double-strand DNA breaks. Moreover, the recent advances in exploring the therapeutic efficacy, toxicity, and MDR (multidrug resistance) issues of new topoisomerase inhibitors have been reviewed in the present review.

Synthesis and Biological Activity of a New Indenoisoquinoline Copper Derivative as a Topoisomerase I Inhibitor

Topoisomerases are interesting targets in cancer chemotherapy. Here, we describe the design and synthesis of a novel copper(II) indenoisoquinoline complex, WN198. The new organometallic compound exhibits a cytotoxic effect on five adenocarcinoma cell lines (MCF-7, MDA-MB-231, HeLa, HT-29, and DU-145) with the lowest IC50 (0.37 ± 0.04 μM) for the triple-negative MDA-MB-231 breast cancer cell line. Below 5 µM, WN198 was ineffective on non-tumorigenic epithelial breast MCF-10A cells and Xenopus oocyte G2/M transition or embryonic development. Moreover, cancer cell lines showed autophagy markers including Beclin-1 accumulation and LC3-II formation. The DNA interaction of this new compound was evaluated and the dose-dependent topoisomerase I activity starting at 1 μM was confirmed using in vitro tests and has intercalation properties into DNA shown by melting curves and fluorescence measurements. Molecular modeling showed that the main interaction occurs with the aromatic ring but copper stabilizes the molecule before binding and so can putatively increase the potency as well. In this way, copper-derived indenoisoquinoline topoisomerase I inhibitor WN198 is a promising antitumorigenic agent for the development of future DNA-damaging treatments.

Anthracyclines inhibit SARS-CoV-2 infection

Vaccines and drugs are two effective medical interventions to mitigate SARS-CoV-2 infection. Three SARS-CoV-2 inhibitors, remdesivir, paxlovid, and molnupiravir, have been approved for treating COVID-19 patients, but more are needed, because each drug has its limitation of usage and SARS-CoV-2 constantly develops drug resistance mutations. In addition, SARS-CoV-2 drugs have the potential to be repurposed to inhibit new human coronaviruses, thus help to prepare for future coronavirus outbreaks. We have screened a library of microbial metabolites to discover new SARS-CoV-2 inhibitors. To facilitate this screening effort, we generated a recombinant SARS-CoV-2 Delta variant carrying the nano luciferase as a reporter for measuring viral infection. Six compounds were found to inhibit SARS-CoV-2 at the half maximal inhibitory concentration (IC50) below 1 μM, including the anthracycline drug aclarubicin that markedly reduced viral RNA-dependent RNA polymerase (RdRp)-mediated gene expression, whereas other anthracyclines inhibited SARS-CoV-2 by activating the expression of interferon and antiviral genes. As the most commonly prescribed anti-cancer drugs, anthracyclines hold the promise of becoming new SARS-CoV-2 inhibitors.

Pediatric acute myeloid leukemia: Insight into genetic landscape and novel targeted approaches

Acute myeloid leukemia (AML) is a very heterogeneous hematological malignancy that accounts for approximately 20% of all pediatric leukemia cases. The outcome of pediatric AML has improved over the last decades, with overall survival rates reaching up to 70%. Still, AML is among the leading types of pediatric cancers by its high mortality rate. Modulation of standard therapy, like chemotherapy intensification, hematopoietic stem cell transplantation and optimized supportive care, could only get this far, but for the significant improvement of the outcome in pediatric AML, development of novel targeted therapy approaches is necessary. In recent years the advances in genomic techniques have greatly expanded our knowledge of the AML biology, revealing molecular landscape and complexity of the disease, which in turn have led to the identification of novel therapeutic targets. This review provides a brief overview of the genetic landscape of pediatric AML, and how it's used for precise molecular characterization and risk stratification of the patients, and also for the development of effective targeted therapy. Furthermore, this review presents recent advances in molecular targeted therapy and immunotherapy with an emphasis on the therapeutic approaches with significant clinical benefits for pediatric AML.

Moringa oleifera: A Review on the Antiproliferative Potential in Breast Cancer Cells

The global burden of female breast cancer and associated deaths has become a major concern. Many chemotherapeutic agents, such as doxorubicin, have been shown to have adverse side effects. The development of multi-drug resistance is a common occurrence, contributing to chemotherapeutic failure. The resistance of breast cancer cells to drug treatment leads to a decline in the treatment efficacy and an increase in cancer recurrence. Therefore, action is required to produce alternative drug therapies, such as herbal drugs. Herbal drugs have been proven to be beneficial in treating illnesses, including cancer. This review aims to highlight the antiproliferative potential of Moringa oleifera (MO), a medicinal tree native to India and indigenous to Africa, in breast cancer cells. Although MO is not yet considered a commercial chemopreventive drug, previous studies have indicated that it could become a chemotherapeutic agent. The possible antiproliferative potential of MO aqueous leaf extract has been previously proven through its antioxidant potential as well as its ability to induce apoptosis. This review will provide an increased understanding of the effect that MO aqueous leaf extract could potentially have against breast cancer.

Chirality in Light-Matter Interaction

The scientific effort to control the interaction between light and matter has grown exponentially in the last 2 decades. This growth has been aided by the development of scientific and technological tools enabling the manipulation of light at deeply sub-wavelength scales, unlocking a large variety of novel phenomena spanning traditionally distant research areas. Here, the role of chirality in light-matter interactions is reviewed by providing a broad overview of its properties, materials, and applications. A perspective on future developments is highlighted, including the growing role of machine learning in designing advanced chiroptical materials to enhance and control light-matter interactions across several scales.

MSN8C: A Promising Candidate for Antitumor Applications as a Novel Catalytic Inhibitor of Topoisomerase II

MSN8C, an analog of mansonone E, has been identified as a novel catalytic inhibitor of human DNA topoisomerase II that induces tumor regression and differs from VP-16(etoposide). Treatment with MSN8C showed significant antiproliferative activity against eleven human tumor cell lines in vitro. It was particularly effective against the HL-60/MX2 cell line, which is resistant to Topo II poisons. The resistance factor (RF) of MSN8C for Topo II in HL-60/MX2 versus HL-60 was 1.7, much lower than that of traditional Topo II poisons. Furthermore, in light of its potent antitumor efficacy and low toxicity, as demonstrated in the A549 tumor xenograft model, MSN8C has been identified as a promising candidate for antitumor applications.

Aclarubicin stimulates RNA polymerase II elongation at closely spaced divergent promoters

Anthracyclines are a class of widely prescribed anticancer drugs that disrupt chromatin by intercalating into DNA and enhancing nucleosome turnover. To understand the molecular consequences of anthracycline-mediated chromatin disruption, we used Cleavage Under Targets and Tagmentation (CUT&Tag) to profile RNA polymerase II during anthracycline treatment in Drosophila cells. We observed that treatment with the anthracycline aclarubicin leads to elevated levels of RNA polymerase II and changes in chromatin accessibility. We found that promoter proximity and orientation affect chromatin changes during aclarubicin treatment, as closely spaced divergent promoter pairs show greater chromatin changes when compared to codirectionally oriented tandem promoters. We also found that aclarubicin treatment changes the distribution of noncanonical DNA G-quadruplex structures both at promoters and at G-rich pericentromeric repeats. Our work suggests that the cancer-killing activity of aclarubicin is driven by the disruption of nucleosomes and RNA polymerase II.

Hazard and health risk assessment of exposure to pharmaceutical active compounds via toxicological evaluation by zebrafish

The uncontrolled or continuous release of effluents from wastewater treatment plants leads to the omnipresence of pharmaceutical active compounds (PhACs) in the aquatic media. Today, this is a confirmed problem becoming a main subject of twin public and scientific concerns. However, still little information is available about the long-term impacts of these PhACs on aquatic organisms. In this review, efforts were made to reveal correlation between the occurrence in the environment, ecotoxicological and health risks of different PhACs via toxicological evaluation by zebrafish (Danio rerio). This animal model served as a bioindicator for any health impacts after the exposure to these contaminants and to better understand the responses in relation to human diseases. This review paper focused on the calculation of Risk Quotients (RQs) of 34 PhACs based on environmental and ecotoxicological data available in the literature and prediction from the ECOSAR V2.2 software. To the best of the authors' knowledge, this is the first report on the risk assessment of PhACs by the two different methods as mentioned above. RQs showed greater difference in potential environmental risks of the PhACs. These differences in risk values underline the importance of environmental and experimental factors in exposure conditions and the interpretation of RQ values. While the results showed high risk to Danio rerio of the majority of PhACs, risk qualification of the others varied between moderate to insignifiant. Further research is needed to assess pharmaceutical hazards when present in wastewater before discharge and monitor the effectiveness of treatment processes. The recent new advances in the morphological assessment of toxicant-exposed zebrafish larvae for the determination of test compounds effects on the developmental endpoints were also discussed. This review emphasizes the need for strict regulations on the release of PhACs into environmental media in order to minimize their toxicity to aquatic organisms.

Cardiac and noncardiac biomarkers in patients undergoing anthracycline chemotherapy - a prospective analysis

BACKGROUND

Biomarkers represent a potential tool to identify individuals at risk for anthracycline-induced cardiotoxicity (AICT) prior to symptom onset or left ventricular dysfunction.

METHODS

This study examined the levels of cardiac and noncardiac biomarkers before, after the last dose of, and 3-6 months after completion of doxorubicin chemotherapy. Cardiac biomarkers included 5th generation high-sensitivity cardiac troponin T (cTnT), N-terminal pro-brain natriuretic peptide, growth/differentiation factor-15 (GDF-15), and soluble suppression of tumorigenesis-2 (sST2). Noncardiac biomarkers included activated caspase-1 (CASP-1), activated caspase-3, C-reactive protein, tumor necrosis factor-α, myeloperoxidase (MPO), galectin-3, and 8-hydroxy-2'-deoxyguanosine. Echocardiographic data (LVEF and LVGLS) were obtained at pre- and post-chemotherapy. Subanalysis examined interval changes in biomarkers among high (cumulative doxorubicin dose ≥ 250 mg/m2) and low exposure groups.

RESULTS

The cardiac biomarkers cTnT, GDF-15, and sST2 and the noncardiac biomarkers CASP-1 and MPO demonstrated significant changes over time. cTnT and GDF-15 levels increased after anthracycline exposure, while CASP-1 and MPO decreased significantly. Subanalysis by cumulative dose did not demonstrate a larger increase in any biomarker in the high-dose group.

CONCLUSIONS

The results identify biomarkers with significant interval changes in response to anthracycline therapy. Further research is needed to understand the clinical utility of these novel biomarkers.

Topoisomerase II inhibitors design: Early studies and new perspectives

The DNA topoisomerase enzymes are widely distributed throughout all spheres of life and are necessary for cell function. Numerous antibacterial and cancer chemotherapeutic drugs target the various topoisomerase enzymes because of their roles in maintaining DNA topology during DNA replication and transcription. Agents derived from natural products, like anthracyclines, epipodophyllotoxins and quinolones, have been widely used to treat a variety of cancers. A very active field of fundamental and clinical research is the selective targeting of topoisomerase II enzymes for cancer treatment. This thematic review summarizes the recent advances in the anticancer activity of the most potent topoisomerase II inhibitors (anthracyclines, epipodophyllotoxins and fluoroquinolones) their modes of action, and structure-activity relationships (SARs) organized chronologically in the last ten years from 2013 to 2023. The review also highlights the mechanism of action and SARs of promising new topoisomerase II inhibitors.

Anticancer Drug Doxorubicin Spontaneously Reacts with GTP and dGTP

Here, we reported a spontaneous reaction between anticancer drug doxorubicin and GTP or dGTP. Incubation of doxorubicin with GTP or dGTP at 37 °C or above yields a covalent product: the doxorubicin-GTP or -dGTP conjugate where a covalent bond is formed between the C14 position of doxorubicin and the 2-amino group of guanine. Density functional theory calculations show the feasibility of this spontaneous reaction. Fluorescence imaging studies demonstrate that the doxorubicin-GTP and -dGTP conjugates cannot enter nuclei although they rapidly accumulate in human SK-OV-3 and NCI/ADR-RES cells. Consequently, the doxorubicin-GTP and -dGTP conjugates are less cytotoxic than doxorubicin. We also demonstrate that doxorubicin binds to ATP, GTP, and other nucleotides with a dissociation constant (Kd) in the sub-millimolar range. Since human cells contain millimolar levels of ATP and GTP, these results suggest that doxorubicin may target ATP and GTP, energy molecules that support essential processes in living organisms.