Anthracyclines: Molecular Advances and Pharmacologic Developments in Antitumor Activity and Cardiotoxicity

Simulation- and AI-directed optimization of 4,6-substituted 1,3,5-triazin-2(1H)-ones as inhibitors of human DNA topoisomerase IIα

The 4,6-substituted-1,3,5-triazin-2(1H)-ones are promising inhibitors of human DNA topoisomerase IIα. To further develop this chemical class targeting the enzyme´s ATP binding site, the triazin-2(1H)-one substitution position 6 was optimized. Inspired by binding of preclinical substituted 9H-purine derivative, bicyclic substituents were incorporated at position 6 and the utility of this modification was validated by a combination of molecular simulations, dynamic pharmacophores, and free energy calculations. Considering also predictions of Deepfrag, a software developed for structure-based lead optimization based on deep learning, compounds with both bicyclic and monocyclic substitutions were synthesized and investigated for their inhibitory activity. The SAR data showed that the bicyclic substituted compounds exhibited good inhibition of topo IIα, comparable to their mono-substituted counterparts. Further evaluation on a panel of human protein kinases showed selectivity for the inhibition of topo IIα. Mechanistic studies indicated that the compounds acted predominantly as catalytic inhibitors, with some exhibiting topo IIα poison effects at higher concentrations. Integration of STD NMR experiments and molecular simulations, provided insights into the binding model and highlighted the importance of the Asn120 interaction and hydrophobic interactions with substituents at positions 4 and 6. In addition, NCI-60 screening demonstrated cytotoxicity of the compounds with bicyclic substituents and identified sensitive human cancer cell lines, underlining the translational relevance of our findings for further preclinical development of this class of compounds. The study highlights the synergy between simulation and AI-based approaches in efficiently guiding molecular design for drug optimization, which has implications for further preclinical development of this class of compounds.

New imidazole-2-thiones linked to acenaphythylenone as dual DNA intercalators and topoisomerase II inhibitors: structural optimization, docking, and apoptosis studies

In this article, a new series of 2-((3,5-disubstituted-2-thioxo-imidazol-1-yl)imino)acenaphthylen-1(2H)-ones were synthesized. Imidazole-2-thione with acenaphthylen-one gave a hybrid scaffold that integrated key structural elements essential for DNA damage via direct DNA intercalation and inhibition of the topoisomerase II enzyme. All the synthesized compounds were screened to detect their DNA damage using a terbium fluorescent probe. Results demonstrated that 4-phenyl-imidazoles 5b and 5e in addition to 4-(4-chlorophenyl)imidazoles 5h and 5j would induce detectable potent damage in ctDNA. The four most potent compounds as DNA intercalators were further evaluated for their antiproliferative activity against HepG2, MCF-7 and HCT-116 utilizing the MTT assay. The highest anticancer activity was recorded with compounds 5b and 5h against the breast cancer cell line MCF-7 which were 1.5- and 3- folds more active than doxorubicin, respectively. Therefore, imidazole-2-thione tethered acenaphthylenone derivatives can be considered as promising scaffold for the development of effective dual DNA intercalators and topoisomerase II inhibitors.

Vericiguat attenuates doxorubicin-induced cardiotoxicity through the PRKG1/PINK1/STING axis

Doxorubicin (DOX) is restricted due to its severe cardiotoxicity. There is still a lack of viable and effective drugs to prevent or treat DOX-induced cardiotoxicity(DIC). Vericiguat is widely used to treat heart failure with reduced ejection fraction. However, it is not clear whether vericiguat can improve DIC. In the present study, we constructed a DIC model using mice and neonatal rat cardiomyocytes and found that vericiguat ameliorated DOX-induced cardiac insufficiency in mice, restored DOX-induced mitochondrial dysfunction in neonatal rat cardiomyocytes, and inhibited the expression of inflammatory factors. Further studies showed that vericiguat improved mitochondrial dysfunction and reduced mtDNA leakage into the cytoplasm by up-regulating PRKG1, which activated PINK1 and then inhibited the STING/IRF3 pathway to alleviate DIC. These findings demonstrate for the first time that vericiguat has therapeutic potential for the treatment of DIC.

Mechanisms of myocardial toxicity of antitumor drugs and potential therapeutic strategies: A review of the literature

With the successive development of chemotherapy drugs, good results have been achieved in clinical application. However, myocardial toxicity is the biggest challenge. Anthracyclines, immune checkpoint inhibitors, and platinum drugs are widely used. Targeted drug delivery, nanomaterials and dynamic imaging evaluation are all emerging research directions. This article reviews the recent literature on the use of targeted nanodrug delivery and imaging techniques to evaluate the myocardial toxicity of antineoplastic drugs, and discusses the potential mechanisms.

Tristetraprolin affects invasion-associated genes expression and cell motility in triple-negative breast cancer model

Tristetraprolin (TTP) is an RNA-binding protein that negatively regulates its target mRNAs and has been shown to inhibit tumor progression and invasion. Tumor invasion requires precise regulation of cytoskeletal components, and dysregulation of cytoskeleton-associated genes can significantly alter cell motility and invasive capability. Several genes, including SH3PXD2A, SH3PXD2B, CTTN, WIPF1, and WASL, are crucial components of the cytoskeleton reorganization machinery and are essential for adequate cell motility. These genes are also involved in invasion processes, with SH3PXD2A, SH3PXD2B, WIPF1, and CTTN being key components of invadopodia-specialized structures that facilitate invasion. However, the regulation of these genes is not well understood. This study demonstrates that ectopic expression of TTP in MDA-MB-231 cells leads to decreased mRNA levels of CTTN and SH3PXD2A, as well as defects in cell motility and actin filament organization. Additionally, doxorubicin significantly increases TTP expression and reduces the mRNA levels of cytoskeleton-associated genes, enhancing our understanding of how doxorubicin may affect the transcriptional profile of cells. However, doxorubicin affects target mRNAs differently than TTP ectopic expression, suggesting it may not be the primary mechanism of doxorubicin in breast cancer (BC) treatment. High TTP expression is considered as a positive prognostic marker in multiple cancers, including BC. Given that doxorubicin is a commonly used drug for treating triple-negative BC, using TTP as a prognostic marker in this cohort of patients might be limited since it might be challenging to understand if high TTP expression occurred due to the favorable physiological state of the patient or as a consequence of treatment.

Targeting sub-cellular organelles for boosting precision photodynamic therapy

Among various cancer treatment methods, photodynamic therapy has received significant attention due to its non-invasiveness and high efficiency in inhibiting tumour growth. Recently, specific organelle targeting photosensitizers have received increasing interest due to their precise accumulation and ability to trigger organelle-mediated cell death signalling pathways, which greatly reduces the drug dosage, minimizes toxicity, avoids multidrug resistance, and prevents recurrence. In this review, recent advances and representative photosensitizers used in targeted photodynamic therapy on organelles, specifically including the endoplasmic reticulum, Golgi apparatus, mitochondria, nucleus, and lysosomes, have been comprehensively reviewed with a focus on organelle structure and organelle-mediated cell death signalling pathways. Furthermore, a perspective on future research and potential challenges in precision photodynamic therapy has been presented at the end.

Multifunctional gallium doped bioactive glasses: a targeted delivery for antineoplastic agents and tissue repair against osteosarcoma

Osteosarcoma (OS) is the mostly commonly occurring primary bone cancer. Despite comprehensive treatment programs including neoadjuvant chemotherapy and tumour resection, survival rates have not improved significantly since the 1970s. Survival rates are dramatically reduced for patients who suffer a local recurrence. Furthermore, primary bone cancer patients are at increased risk of bone fractures. Consequently, there is an urgent need for alternative treatment options. In this paper we report the development of novel gallium doped bioactive glass that selectively kill bone cancer cells whilst simultaneously stimulating new bone growth. Here we show, using a combination of 3-(4.5-dimethylthiazol-2-yl)-2.5-diphenyltetrazolium bromide, LIVE/DEAD assays and image analysis, that bioactive glasses containing gallium oxide are highly toxic and reduce both the proliferation and migration of bone cancer cells (Saos-2) in a dose dependant manner. Glasses containing 5 mol% gallium oxide reduced the viability of OS cells by 99% without being cytotoxic to the non-cancerous normal human osteoblasts (NHOst) control cells. Furthermore, Fourier transform infrared and energy-dispersive x-ray spectroscopy results confirmed the formation of an amorphous calcium phosphate/hydroxyapatite like layer on the surface of the bioactive glass particulates, after 7 d incubating in simulated body fluid, indicating the early stages of bone formation. These materials show significant potential for use in bone cancer applications as part of a multimodal treatment.

SZ-685C inhibits the growth of non-functioning pituitary adenoma by down-regulating miR-340-3p and inducing autophagy

Background

SZ-685C, an anthracycline compound derived from the mangrove endophytic fungus Halorosellinia sp. (No. 1403) collected from the South China Sea, has shown strong anticancer activities. Non-functioning pituitary adenomas (NFPAs) are a type of tumor that can be challenging to manage clinically and have a significant unmet medical need. Our research has found that SZ-685C showed an inhibitory effect on the viability, migration ability, and proliferation ability of a human non-functioning pituitary tumor-derived folliculostellate (PDFS) cell line.

Methods

SZ-685C was prepared and purified from the mangrove endophytic fungus No. 1403. PDFS cells were exposed to SZ-685C, and the effect of SZ-685C on PDFS cells was evaluated. RNA sequencing was used to analyze the miRNA expression profile in PDFS cells of the control group and SZ-685C-treated group. Quantitative polymerase chain reaction (qPCR) was performed to verify the expression of selected miR-340-3p. The effects of SZ-685C on PDFS cells after overexpression of miR-340-3p were evaluated. Dual-luciferase reporter assays showed PPP1CB is a direct target of miR-340-3p. Finally, the action pathway of the selected miR-340-3p was predicted and evaluated through bioinformatics analysis.

Results

SZ-685C reduced cell viability in PDFS cells, accompanied by inhibition of migration ability and proliferation ability. The IC50 value for 24 h is 9.144 ± 0.991 μM, and for 48 h is 4.635 ± 0.551 μM. SZ-685C increased the protein levels of Beclin 1, the ratio of LC3-II to LC3-I, and LAMP-1, and down-regulated p62. MiRNA sequencing and further validation showed that miR-340-3p significantly decreased in PDFS cells treated with SZ-685C. After overexpression of miR-340-3p, the inhibition of viability, migration ability, proliferation ability, and autophagy-promoting effect of SZ-685C on PDFS cells were weakened. SZ-685C caused a decrease in PPP1CB expression and activation of the ERK pathway in PDFS cells, and this trend was reversed after overexpression of miR-340-3p.

Conclusions

SZ-685C downregulates the expression of miR-340-3p in PDFS cells, thereby reducing the expression of PPP1CB and activating the ERK pathway to promote autophagic cell death, leading to inhibition of PDFS cell growth.

Engineered liver-derived decellularized extracellular matrix-based three-dimensional tumor constructs for enhanced drug screening efficiency

The decellularized extracellular matrix (dECM) has emerged as an effective medium for replicating the in vivo-like conditions of the tumor microenvironment (TME), thus enhancing the screening accuracy of chemotherapeutic agents. However, recent dECM-based tumor models have exhibited challenges such as uncontrollable morphology and diminished cell viability, hindering the precise evaluation of chemotherapeutic efficacy. Herein, we utilized a tailor-made microfluidic approach to encapsulate dECM from porcine liver in highly poly(lactic-co-glycolic acid) (PLGA) porous microspheres (dECM-PLGA PMs) to engineer a three-dimensional (3D) tumor model. These dECM-PLGA PMs-based microtumors exhibited significant promotion of hepatoma carcinoma cells (HepG2) proliferation compared to PLGA PMs alone, since the infusion of extracellular matrix (ECM) microfibers and biomolecular constituents within the PMs. Proteomic analysis of the dECM further revealed the potential effects of these bioactive fragments embedded in the PMs. Notably, dECM-PLGA PMs-based microtissues effectively replicated the drug resistance traits of tumors, showing pronounced disparities in half-maximal inhibitory concentration (IC50) values, which could correspond with certain aspects of the TME. Collectively, these dECM-PLGA PMs substantially surmounted the prevalent challenges of unregulated microstructure and suboptimal cell viability in conventional 3D tumor models. They also offer a sustainable and scalable platform for drug testing, holding promise for future pharmaceutical evaluations.

Cytotoxicity of Doxorubicin-Curcumin Nanoparticles Conjugated with Two Different Peptides (CKR and EVQ) against FLT3 Protein in Leukemic Stem Cells

A targeted micellar formation of doxorubicin (Dox) and curcumin (Cur) was evaluated to enhance the efficacy and reduce the toxicity of these drugs in KG1a leukemic stem cells (LSCs) compared to EoL-1 leukemic cells. Dox-Cur-micelle (DCM) was developed to improve the cell uptake of both compounds in LSCs. Cur-micelle (CM) was produced to compare with DCM. DCM and CM were conjugated with two FLT3 (FMS-like tyrosine kinase)-specific peptides (CKR; C and EVQ; E) to increase drug delivery to KG1a via the FLT3 receptor (AML marker). They were formulated using a film-hydration technique together with a pH-induced self-assembly method. The optimal drug-to-polymer weight ratios for the DCM and CM formulations were 1:40. The weight ratio of Dox and Cur in DCM was 1:9. DCM and CM exhibited a particle size of 20-25 nm with neutral charge and a high %EE. Each micelle exhibited colloidal stability and prolonged drug release. Poloxamer 407 (P407) was modified with terminal azides and conjugated to FLT3-targeting peptides with terminal alkynes. DCM and CM coupled with peptides C, E, and C + E exhibited a higher particle size. Moreover, DCM-C + E and CM-C + E showed the highest toxicity in KG-1a and EoL-1 cells. Using two peptides likely improves the probability of micelles binding to the FLT3 receptor and induces cytotoxicity in leukemic stem cells.

Peptide-drug conjugate designated for targeted delivery to HER2-expressing cancer cells

Targeted therapy of the highest globally incident breast cancer shall resolve the issue of off-target toxicity concurring with augmented killing of specific diseased cells. Thus, the goal of this study was to prepare a peptide-drug conjugate targeting elevated expression of HER2 receptors in breast cancer. Towards this, the rL-A9 peptide was conjugated with the chemotherapeutic drug doxorubicin (DOX) through a N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) linker. The synthesized peptide-drug conjugate, rL-A9-DOX, was characterized by mass spectrometry. Molecular docking studies, based on binding energy data, suggested a stronger interaction of rL-A9-DOX with the HER2 receptor in comparison to the unconjugated peptide, rL-A9. The cytotoxic effect of the rL-A9-DOX conjugate was observed to be higher in HER2-positive SKOV3 cells compared to HER2-negative MDA-MB-231 cells, indicating selective cell killing. Cellular internalization of the rL-A9-DOX conjugate was evident from the flow cytometry analysis, where a noticeable shift in mean fluorescent intensity (MFI) was observed for the conjugate compared to the control group. This data was further validated by confocal microscopy, where the fluorescent signal ascertained nuclear accumulation of rL-A9-DOX. The present studies highlight the promising potential of rL-A9-DOX for targeted delivery of the drug into a defined group of cancer cells.

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

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

A Robust Chromatographic Method for Drug Release profiling of liposomal doxorubicin HCl

Liposomes are excellent drug delivery vehicles for chemotherapeutics as they may change the pharmacokinetics of therapeutic compounds, resulting in altered tissues distribution, and in some cases, reduced cytotoxicity and enhanced distribution and efficacy of the active pharmaceutical ingredient (API) at target tissues. Drug release profiles of liposomal formulations are crucial to support equivalence evaluation and quality control in pre- and post-approval stages. We developed an automated chromatographic method for quantifying the drug release profile of liposomal formulations containing doxorubicin to overcome the shortcomings of currently available methods. The newly developed method employs nanoparticle exclusion chromatography (nPEC), using a monolithic silica column coated with polyvinylpyrrolidone to separate the released drug from liposomal encapsulated drug. We evaluated the effects of pH, temperature, and ammonium formate concentration on the drug release rate. The optimized release buffer consisting of 5 % sucrose, 20 mM l-histidine, and 200 mM ammonium formate was selected for the drug release profiling of five liposomal formulations at 47 °C. The drug release profiles of five liposomal doxorubicin formulations were similar. Our automated method requires very small amounts of the sample and provides release profiles with high sensitivity and accuracy. In addition, this method can be applied to other liposomal products to allow for simple, fast, and accurate analysis of in vitro drug release profiling.

Curcumin Attenuates Doxorubicin-Induced Cardiac Oxidative Stress and Increases Survival in Mice

Doxorubicin (DOX) is a potent chemotherapeutic agent used to treat multiple types of cancer, but its clinical application is limited by cardiotoxicity, mainly due to oxidative stress. Curcumin (CUR) is a natural polyphenolic compound with strong antioxidant properties, but its potential protective effects against DOX-induced cardiotoxicity need further investigation. This study aimed to evaluate CUR's efficacy in mitigating DOX-induced oxidative stress in the hearts of BALB/c mice. Mice received a DOX dose of 9 mg/kg or 16 mg/kg; half of the mice received daily doses of 100 mg/kg CUR for 15 days. Survival analysis, histopathological examination, and oxidative stress markers were assessed to determine the cardioprotective effects of CUR. Results showed that CUR significantly reduced oxidative damage and improved survival rates, particularly at the lower DOX dose (9 mg/kg). Mice treated with DOX-9 mg/kg plus CUR showed improved health conditions and reduced levels of reactive oxygen species (ROS), lipid peroxidation, sulfhydryl production, and protein carbonylation. Histopathological analysis confirmed reduced cardiac tissue damage. In conclusion, CUR combined with a lower dose of DOX effectively reduces oxidative stress and cardiac injury, enhancing survival in BALB/c mice. These findings suggest that CUR is a promising adjunct therapy to mitigate DOX-induced cardiotoxicity, potentially improving the DOX therapeutic index in cancer treatment.

DNA damage-associated protein co-expression network in cardiomyocytes informs on tolerance to genetic variation and disease

Cardiovascular disease (CVD) is associated with both genetic variants and environmental factors. One unifying consequence of the molecular risk factors in CVD is DNA damage, which must be repaired by DNA damage response proteins. However, the impact of DNA damage on global cardiomyocyte protein abundance, and its relationship to CVD risk remains unclear. We therefore treated induced pluripotent stem cell-derived cardiomyocytes with the DNA-damaging agent Doxorubicin (DOX) and a vehicle control, and identified 4,178 proteins that contribute to a network comprising 12 co-expressed modules and 403 hub proteins with high intramodular connectivity. Five modules correlate with DOX and represent distinct biological processes including RNA processing, chromatin regulation and metabolism. DOX-correlated hub proteins are depleted for proteins that vary in expression across individuals due to genetic variation but are enriched for proteins encoded by loss-of-function intolerant genes. While proteins associated with genetic risk for CVD, such as arrhythmia are enriched in specific DOX-correlated modules, DOX-correlated hub proteins are not enriched for known CVD risk proteins. Instead, they are enriched among proteins that physically interact with CVD risk proteins. Our data demonstrate that DNA damage in cardiomyocytes induces diverse effects on biological processes through protein co-expression modules that are relevant for CVD, and that the level of protein connectivity in DNA damage-associated modules influences the tolerance to genetic variation.

Applications of nanotechnology in remodeling the tumour microenvironment for glioblastoma treatment

With the increasing research and deepening understanding of the glioblastoma (GBM) tumour microenvironment (TME), novel and more effective therapeutic strategies have been proposed. The GBM TME involves intricate interactions between tumour and non-tumour cells, promoting tumour progression. Key therapeutic goals for GBM treatment include improving the immunosuppressive microenvironment, enhancing the cytotoxicity of immune cells against tumours, and inhibiting tumour growth and proliferation. Consequently, remodeling the GBM TME using nanotechnology has emerged as a promising approach. Nanoparticle-based drug delivery enables targeted delivery, thereby improving treatment specificity, facilitating combination therapies, and optimizing drug metabolism. This review provides an overview of the GBM TME and discusses the methods of remodeling the GBM TME using nanotechnology. Specifically, it explores the application of nanotechnology in ameliorating immune cell immunosuppression, inducing immunogenic cell death, stimulating, and recruiting immune cells, regulating tumour metabolism, and modulating the crosstalk between tumours and other cells.

Nano-emulsion based on Santolina chamaecyparissus essential oil potentiates the cytotoxic and apoptotic effects of Doxorubicin: an in vitro study

AIM

This study was aimed at investigating the cytotoxic effect of a novel combination of doxorubicin (DOX) and nano-formulation of Santolina chamaecyparissus L. essential oil (SCEO-NANO) on hepatic (HepG2) and colon (HT29) cancer cell lines.

METHODS

A nano-emulsion was prepared by high-pressure homogenisation, then analysed by zetasizer and Fourier transform infrared spectroscopy. HepG2 and HT29 cells were used in in vitro tests for apoptosis detection.

RESULTS

Formulated droplet size increased in DOX@SCEO-NANO/DOX to 11.54 ± 0.02 with uniform distribution (PDI = 0.13 ± 0.01), when compared with SCEO-NANO (size: 8.91 ± 0.02 nm; PDI = 0.1 ± 0.02). In both cells, DOX@SCEO-NANO/DOX led to a considerable reduction in colony formation. Compared to DOX, apoprotein proteins were overexpressed in HepG2 cells, showing increases of 8.66-fold for caspase-3 and 4.24-fold for the Bax/Bcl-2 ratio. In HT29 cells, ROS-dependent necrosis and apoptosis were seen. Comparing DOX@SCEO-NANO/DOX versus DOX, greater levels of caspase-3 and the Bax/Bcl-2 ratio were observed.

CONCLUSION

The DOX@SCEO-NANO/DOX formulation showed potential for targeted eradication of colon adenocarcinoma and hepatocellular carcinoma cells.

Doxorubicin as a Drug Repurposing for Disruption of α-Chymotrypsinogen-A Aggregates

Protein conformation is affected by interaction of several small molecules resulting either stabilization or disruption depending on the nature of the molecules. In our earlier communication, Hg2+ was known to disrupt the native structure of α-Cgn A leading to aggregation (Ansari, N.K., Rais, A. & Naeem, A. Methotrexate for Drug Repurposing as an Anti-Aggregatory Agent to Mercuric Treated α-Chymotrypsinogen-A. Protein J (2024). https://doi.org/10.1007/s10930-024-10187-z ). Accumulation of β-rich aggregates in the living system is found to be linked with copious number of disorders. Here, we have investigated the effect of varying concentration of doxorubicin (DOX) i.e. 0-100 µM on the preformed aggregates of α-Cgn A upon incubation with 120 µM Hg2+. The decrease in the intrinsic fluorescence and enzyme activity with respect to increase in the Hg2+ concentration substantiate the formation of aggregates. The DOX showed the dose dependent decrease in the ThT fluorescence, turbidity and RLS measurements endorsing the dissolution of aggregates which were consistent with red shift in ANS, confirming the breakdown of aggregates. The α-Cgn A has 30% α-helical content which decreases to 3% in presence of Hg2+. DOX increased the α-helicity to 28% confirming its anti-aggregatory potential. The SEM validates the formation of aggregates with Hg2+ and their dissolution upon incubation with the DOX. Hemolysis assay checked the cytotoxicity of α-Cgn A aggregates. Docking revealed that the DOX interacted Lys203, Cys201, Cys136, Ser159, Leu10, Trp207, Val137 and Thr134 of α-Cgn A through hydrophobic interactions and Gly133, Thr135 and Lys202 forms hydrogen bonds.

Precision Treatment of Anthracycline-Induced Cardiotoxicity: An Updated Review

OPINION STATEMENT

Anthracycline (ANT)-induced cardiotoxicity (AIC) is a particularly prominent form of cancer therapy-related cardiovascular toxicity leading to the limitations of ANTs in clinical practice. Even though AIC has drawn particular attention, the best way to treat it is remaining unclear. Updates to AIC therapy have been made possible by recent developments in research on the underlying processes of AIC. We review the current molecular pathways leading to AIC: 1) oxidative stress (OS) including enzymatic-induced and other mechanisms; 2) topoisomerase; 3) inflammatory response; 4) cardiac progenitor cell damage; 5) epigenetic changes; 6) renin-angiotensin-aldosterone system (RAAS) dysregulation. And we systematically discuss current prevention and treatment strategies and novel pathogenesis-based therapies for AIC: 1) dose reduction and change; 2) altering drug delivery methods; 3) antioxidants, dexrezosen, statina, RAAS inhibitors, and hypoglycemic drugs; 4) miRNA, natural phytochemicals, mesenchymal stem cells, and cardiac progenitor cells. We also offer a fresh perspective on the management of AIC by outlining the current dilemmas and challenges associated with its prevention and treatment.

Aclarubicin: contemporary insights into its mechanism of action, toxicity, pharmacokinetics, and clinical standing

Aclarubicin (aclacinomycin A) is one of the anthracycline antineoplastic antibiotics with a multifaceted mechanism of antitumor activity. As a second-generation drug, it offers several advantages compared to standard anthracycline drugs such as doxorubicin or daunorubicin, which could position it as a potential blockbuster drug in antitumor therapy. Key mechanisms of action for aclarubicin include the inhibition of both types of topoisomerases, suppression of tumor invasion processes, generation of reactive oxygen species, inhibition of chymotrypsin-like activity, influence on cisplatin degradation, and inhibition of angiogenesis. Therefore, aclarubicin appears to be an ideal candidate for antitumor therapy. However, despite initial interest in its clinical applications, only a limited number of high-quality trials have been conducted thus far. Aclarubicin has primarily been evaluated as an induction therapy in acute myeloid and lymphoblastic leukemia. Studies have indicated that aclarubicin may hold significant promise for combination therapies with other anticancer drugs, although further research is needed to confirm its potential. This paper provides an in-depth exploration of aclarubicin's diverse mechanisms of action, its pharmacokinetics, potential toxicity, and the clinical trials in which it has been investigated.

Anthracyclines, Diastolic Dysfunction and the road to Heart Failure in Cancer survivors: An untold story

Many cardiovascular diseases are characterized by diastolic dysfunction, which associates with worse clinical outcomes like overall mortality and hospitalization for heart failure (HF). Diastolic dysfunction has also been suspected to represent an early manifestation of cardiotoxicity induced by cancer drugs, with most of the information deriving from patients treated with anthracyclines; however, the prognostic implications of diastolic dysfunction in the anthracycline-treated patient have remained poorly explored or neglected. Here the molecular, pathophysiologic and diagnostic aspects of anthracycline-related diastolic dysfunction are reviewed in the light of HF incidence and phenotype in cancer survivors. We describe that the trajectories of diastolic dysfunction toward HF are influenced by a constellation of patient- or treatment- related factors, such as comorbidities and exposure to other cardiotoxic drugs or treatments, but also by prospective novel opportunities to treat diastolic dysfunction. The importance of a research-oriented multidimensional approach to patient surveillance or treatment is discussed within the framework of what appears to be a distinct pathophysiologic entity that develops early during anthracycline treatment and gradually worsens over the years.

Improved anti-breast cancer activity by doxorubicin-loaded super stealth liposomes

PEGylation is currently used for the synthesis of stealth liposomes and to enhance the pharmacokinetic and biopharmaceutical properties of payloads. PEGylated dendron phospholipids can decrease the detachment of polyethylene glycol (PEG) from the liposomal surface owing to an increased hydrophobic anchoring effect on the phospholipid bilayer of liposomes and thus generating super stealth liposomes that are suitable for the systemic delivery of anticancer drugs. Herein, doxorubicin hydrochloride-loaded super stealth liposomes were studied for the treatment of breast cancer lung metastasis in an animal model. The results demonstrated that the super stealth liposomes had suitable physicochemical properties for in vivo administration and could significantly increase the efficacy of doxorubicin in breast cancer lung metastasis tumor-bearing mice compared to the free drug. The super stealth liposomes also increased doxorubicin accumulation inside the tumor tissue. The permanence of PEG on the surface of the super stealth liposomes favored the formation of a depot of therapeutic nanocarriers inside the tumor tissue by improving their permanence after stopping treatment. The doxorubicin-loaded super stealth liposomes increased the survival of the mouse tumor model. These promising results demonstrate that the doxorubicin-loaded super stealth liposomes could be an effective nanomedicine to treat metastatic breast cancer.

Pediatric Cardio-Oncology: Screening, Risk Stratification, and Prevention of Cardiotoxicity Associated with Anthracyclines

Anthracyclines have significantly improved the survival of children with malignant tumors, but the associated cardiotoxicity, an effect now under the purview of pediatric cardio-oncology, due to its cumulative and irreversible effects on the heart, limits their clinical application. A systematic screening and risk stratification approach provides the opportunity for early identification and intervention to mitigate, reverse, or prevent myocardial injury, remodeling, and dysfunction associated with anthracyclines. This review summarizes the risk factors, surveillance indexes, and preventive strategies of anthracycline-related cardiotoxicity to improve the safety and efficacy of anthracyclines.

Visible-light-induced Ritter-type amidation of α-hydroxy ketones in the selective synthesis of α,α-diamido and monoamido ketones

Visible light-induced, transition metal-free oxidative dehydroxylation and C-H amidation of α-hydroxy ketones involving Ritter-type amidation has been developed, leading to the selective synthesis of α,α-diamido- and α-monoamido ketones with tunable selectivity as well as broad substrate tolerance.

Multifunctional Molecular Hybrids Photoreleasing Nitric Oxide: Advantages, Pitfalls, and Opportunities

The multifaceted role nitric oxide (NO) plays in human physiology and pathophysiology has opened new scenarios in biomedicine by exploiting this free radical as an unconventional therapeutic against important diseases. The difficulties in handling gaseous NO and the strict dependence of the biological effects on its doses and location have made the light-activated NO precursors, namely NO photodonors (NOPDs), very appealing by virtue of their precise spatiotemporal control of NO delivery. The covalent integration of NOPDs and additional functional components within the same molecular skeleton through suitable linkers can lead to an intriguing class of multifunctional photoactivatable molecular hybrids. In this Perspective, we provide an overview of the recent advances in these molecular constructs, emphasizing those merging NO photorelease with targeting, fluorescent reporting, and phototherapeutic functionalities. We will highlight the rational design behind synthesizing these molecular hybrids and critically describe the advantages, drawbacks, and opportunities they offer in biomedical research.

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.

Hepatic IRE1α-XBP1 signaling promotes GDF15-mediated anorexia and body weight loss in chemotherapy

Platinum-based chemotherapy drugs can lead to the development of anorexia, a detrimental effect on the overall health of cancer patients. However, managing chemotherapy-induced anorexia and subsequent weight loss remains challenging due to limited effective therapeutic strategies. Growth differentiation factor 15 (GDF15) has recently gained significant attention in the context of chemotherapy-induced anorexia. Here, we report that hepatic GDF15 plays a crucial role in regulating body weight in response to chemo drugs cisplatin and doxorubicin. Cisplatin and doxorubicin treatments induce hepatic Gdf15 expression and elevate circulating GDF15 levels, leading to hunger suppression and subsequent weight loss. Mechanistically, selective activation by chemotherapy of hepatic IRE1α-XBP1 pathway of the unfolded protein response (UPR) upregulates Gdf15 expression. Genetic and pharmacological inactivation of IRE1α is sufficient to ameliorate chemotherapy-induced anorexia and body weight loss. These results identify hepatic IRE1α as a molecular driver of GDF15-mediated anorexia and suggest that blocking IRE1α RNase activity offers a therapeutic strategy to alleviate the adverse anorexia effects in chemotherapy.

Visnagin: A novel cardioprotective agent against anthracycline toxicity (Review)

Doxorubicin (DOX), a cornerstone of cancer chemotherapy, is marred by its dose-dependent cardiotoxicity, leading to cardiomyopathy and heart failure. The epidemiology of DOX-related cardiotoxicity highlights its cumulative, progressive nature, with a significant impact on the health of patients. The pathophysiological mechanisms involve mitochondrial dysfunction, oxidative stress and disrupted calcium homeostasis in cardiomyocytes. Despite the search for effective cardioprotective strategies, current treatments offer limited efficacy. Visnagin emerges as a potential solution, known for its vasodilatory and anti-inflammatory properties, and recent studies suggest its cardioprotective efficacy against DOX-induced cardiotoxicity through mitochondrial protection, the modulation of key signaling pathways and the inhibition of apoptosis. The present review aimed to provide a comprehensive overview of the mechanisms of action of visnagin, as well as to provide experimental evidence, and potential integration into cancer treatment regimens, highlighting its promise as a novel therapeutic agent for managing cardiotoxicity in patients undergoing anthracycline chemotherapy.

Improving Chemotherapy Effectiveness: Utilizing CuS Nanoparticles Coated with AS1411 Aptamer and Chitosan for Targeted Delivery of Doxorubicin to Cancerous Cells

Here, a novel targeted nanostructure complex was designed as an alternative to the traditional treatment approaches for breast cancer. A delivery system utilizing CuS nanoparticles (CuS NPs) was developed for the purpose of targeted administration of doxorubicin (Dox), an anticancer agent. To regulate Dox release, chitosan (CS), a biodegradable and hydrophilic polymer with biocompatible properties, was applied to coat the Dox-loaded CuS NPs. Furthermore, AS1411 aptamer, served as a targeting agent for breast cancer cells (MCF-7 and 4T1 cells), was conjugated with CS-Dox-CuS NPs effectively. To assess the effectiveness of APT-CS-CuS NPs, various methods such as flow cytometry analysis, MTT assay, fluorescence imaging, and in vivo antitumor efficacy were employed. The hollow core and porous surface of CuS NPs improved the Dox loading capacity and entrapment efficiency (almost 100%). The rate of drug release at the tumor site (citrate buffer with pH 5.6) exhibited a marked increase in comparison to that observed within the physiological environment (phosphate buffer with pH 7.4). The targeted formulation (APT-CS-Dox-CuS NPs) significantly increased cytotoxicity of the Dox payload in target cells, including 4T1 (p ≤ 0.0001 (****)) and MCF7 (p ≤ 0.01 (**)) cells compared to CHO cells. Moreover, the ability of tumor growth inhibition of the targeted system was significantly (p ≤ 0.05 (*)) more than free Dox in tumor-bearing mice. The findings indicate that the targeted formulation augmented effectiveness and specificity while minimizing harm to non-targeted cells, signifying its potential as a sophisticated cancer drug delivery system.

An update of the molecular mechanisms underlying anthracycline induced cardiotoxicity

Anthracycline drugs mainly include doxorubicin, epirubicin, pirarubicin, and aclamycin, which are widely used to treat a variety of malignant tumors, such as breast cancer, gastrointestinal tumors, lymphoma, etc. With the accumulation of anthracycline drugs in the body, they can induce serious heart damage, limiting their clinical application. The mechanism by which anthracycline drugs cause cardiotoxicity is not yet clear. This review provides an overview of the different types of cardiac damage induced by anthracycline-class drugs and delves into the molecular mechanisms behind these injuries. Cardiac damage primarily involves alterations in myocardial cell function and pathological cell death, encompassing mitochondrial dysfunction, topoisomerase inhibition, disruptions in iron ion metabolism, myofibril degradation, and oxidative stress. Mechanisms of uptake and transport in anthracycline-induced cardiotoxicity are emphasized, as well as the role and breakthroughs of iPSC in cardiotoxicity studies. Selected novel cardioprotective therapies and mechanisms are updated. Mechanisms and protective strategies associated with anthracycline cardiotoxicity in animal experiments are examined, and the definition of drug damage in humans and animal models is discussed. Understanding these molecular mechanisms is of paramount importance in mitigating anthracycline-induced cardiac toxicity and guiding the development of safer approaches in cancer treatment.

Systematic analysis of PANoptosis-related genes identifies XIAP as a functional oncogene in breast cancer

BACKGROUND

Breast cancer (BC) is the most prevalent malignant disease affecting women globally. PANoptosis, a novel form of cell death combining features of pyroptosis, apoptosis, and necroptosis, has recently gained attention. However, its precise function in BC and the predictive values of PANoptosis-related genes remain unclear.

METHODS

We used the expression data and clinical information of BC tissues or normal breast tissues from public databases, and then successfully developed and verified a BC PANoptosis-related risk model through a combination of univariate Cox regression, least absolute shrinkage and selection operator (LASSO) regression, and Kaplan-Meier (KM) analysis. A nomogram was constructed to estimate survival probability, and its accuracy was assessed using calibration curves.

RESULTS

Among 37 PANoptosis-related genes, we identified 4 differentially expressed genes related to overall survival (OS). Next, a risk model incorporating these four PANoptosis-related genes was established. Patients were stratified into low/high-risk groups based on the median risk score, with the low-risk group showing better prognoses and higher levels of immune infiltration. Utilizing the risk score and clinical features, we developed a nomogram to predict 1-, 3- and 5-year survival probability. X-linked inhibitor of apoptosis protein (XIAP) emerged as a potentially risky factor with the highest hazard ratio. In vitro experiments demonstrated that XIAP inhibition enhances the antitumor effect of doxorubicin through the PANoptosis pathway.

CONCLUSION

PANoptosis holds an important role in BC prognosis and treatment.

Assessing genotoxic effects of chemotherapy agents by a robust in vitro assay based on mass spectrometric quantification of γ-H2AX in HepG2 cells

Chemotherapy has already proven widely effective in treating cancer. Chemotherapeutic agents usually include DNA damaging agents and non-DNA damaging agents. Assessing genotoxic effect is significant during chemotherapy drug development, since the ability to attack DNA is the major concern for DNA damaging agents which relates to the therapeutic effect, meanwhile genotoxicity should also be evaluated for chemotherapy agents' safety especially for non-DNA damaging agents. However, currently applicability of in vitro genotoxicity assays is hampered by the fact that genotoxicity results have comparatively high false positive rates. γ-H2AX has been shown to be a bifunctional biomarker reflecting both DNA damage response and repair. Previously, we developed an in vitro genotoxicity assay based on γ-H2AX quantification using mass spectrometry. Here, we employed the assay to quantitatively assess the genotoxic effects of 34 classic chemotherapy agents in HepG2 cells. Results demonstrated that the evaluation of cellular γ-H2AX could be an effective approach to screen and distinguish types of action of different classes of chemotherapy agents. In addition, two crucial indexes of DNA repair kinetic curve, i.e., k (speed of γ-H2AX descending) and t50 (time required for γ-H2AX to drop to half of the maximum value) estimated by our developed online tools were employed to further evaluate nine representative chemotherapy agents, which showed a close association with therapeutic index or carcinogenic level. The present study demonstrated that mass spectrometric quantification of γ-H2AX may be an appropriate tool to preliminarily evaluate genotoxic effects of chemotherapy agents.

Generation of Hydrogen Peroxide in Cancer Cells: Advancing Therapeutic Approaches for Cancer Treatment

Cancer cells show altered antioxidant defense systems, dysregulated redox signaling, and increased generation of reactive oxygen species (ROS). Targeting cancer cells through ROS-mediated mechanisms has emerged as a significant therapeutic strategy due to its implications in cancer progression, survival, and resistance. Extensive research has focused on selective generation of H2O2 in cancer cells for selective cancer cell killing by employing various strategies such as metal-based prodrugs, photodynamic therapy, enzyme-based systems, nano-particle mediated approaches, chemical modulators, and combination therapies. Many of these H2O2-amplifying approaches have demonstrated promising anticancer effects and selectivity in preclinical investigations. They selectively induce cytotoxicity in cancer cells while sparing normal cells, sensitize resistant cells, and modulate the tumor microenvironment. However, challenges remain in achieving selectivity, addressing tumor heterogeneity, ensuring efficient delivery, and managing safety and toxicity. To address those issues, H2O2-generating agents have been combined with other treatments leading to optimized combination therapies. This review focuses on various chemical agents/approaches that kill cancer cells via H2O2-mediated mechanisms. Different categories of compounds that selectively generate H2O2 in cancer cells are summarized, their underlying mechanisms and function are elucidated, preclinical and clinical studies as well as recent advancements are discussed, and their prospects as targeted therapeutic agents and their therapeutic utility in combination with other treatments are explored. By understanding the potential of these compounds, researchers can pave the way for the development of effective and personalized cancer treatments.

Perturbation-Specific Transcriptional Mapping for unbiased target elucidation of antibiotics

The rising prevalence of antibiotic resistance threatens human health. While more sophisticated strategies for antibiotic discovery are being developed, target elucidation of new chemical entities remains challenging. In the post-genomic era, expression profiling can play an important role in mechanism-of-action (MOA) prediction by reporting on the cellular response to perturbation. However, the broad application of transcriptomics has yet to fulfill its promise of transforming target elucidation due to challenges in identifying the most relevant, direct responses to target inhibition. We developed an unbiased strategy for MOA prediction, called Perturbation-Specific Transcriptional Mapping (PerSpecTM), in which large-throughput expression profiling of wildtype or hypomorphic mutants, depleted for essential targets, enables a computational strategy to address this challenge. We applied PerSpecTM to perform reference-based MOA prediction based on the principle that similar perturbations, whether chemical or genetic, will elicit similar transcriptional responses. Using this approach, we elucidated the MOAs of three new molecules with activity against Pseudomonas aeruginosa by comparing their expression profiles to those of a reference set of antimicrobial compounds with known MOAs. We also show that transcriptional responses to small molecule inhibition resemble those resulting from genetic depletion of essential targets by CRISPRi by PerSpecTM, demonstrating proof-of-concept that correlations between expression profiles of small molecule and genetic perturbations can facilitate MOA prediction when no chemical entities exist to serve as a reference. Empowered by PerSpecTM, this work lays the foundation for an unbiased, readily scalable, systematic reference-based strategy for MOA elucidation that could transform antibiotic discovery efforts.

Anthracycline-induced hypertension in pediatric cancer survivors: unveiling the long-term cardiovascular risks

BACKGROUND

Long-term cardiovascular complications are common among pediatric cancer survivors, and anthracycline-induced hypertension has become an essential reason for concern. Compared to non-cancer controls, survivors have a higher prevalence of hypertension, and as they age, their incidence rises, offering significant dangers to cardiovascular health.

MAIN BODY

Research demonstrates that exposure to anthracyclines is a major factor in the development of hypertension in children who have survived cancer. Research emphasizes the frequency and risk factors of anthracycline-induced hypertension, highlighting the significance of routine measurement and management of blood pressure. Furthermore, cardiovascular toxicities, such as hypertension, after anthracycline-based therapy are a crucial be concerned, especially for young adults and adolescents. Childhood cancer survivors deal with a variety of cardiovascular diseases, such as coronary artery disease and cardiomyopathy, which are made worse by high blood pressure. In order to prevent long-term complications, it is essential to screen for and monitor for anthracycline-induced hypertension. Echocardiography and cardiac biomarkers serve as essential tools for early detection and treatment. In order to lower cardiovascular risks in pediatric cancer survivors, comprehensive management strategies must include lifestyle and medication interventions in addition to survivor-centered care programs.

SHORT CONCLUSION

Proactive screening, monitoring, and management measures are necessary for juvenile cancer survivors due to the substantial issue of anthracycline-induced hypertension in their long-term care. To properly include these strategies into survivor-ship programs, oncologists, cardiologists, and primary care physicians need to collaborate together. The quality of life for pediatric cancer survivors can be enhanced by reducing the cardiovascular risks linked to anthracycline therapy and promoting survivor-centered care and research.

DOX-DNA Interactions on the Nanoscale: In Situ Studies Using Tip-Enhanced Raman Scattering

Chemotherapeutic anthracyclines, like doxorubicin (DOX), are drugs endowed with cytostatic activity and are widely used in antitumor therapy. Their molecular mechanism of action involves the formation of a stable anthracycline-DNA complex, which prevents cell division and results in cell death. It is known that elevated DOX concentrations induce DNA chain loops and overlaps. Here, for the first time, tip-enhanced Raman scattering was used to identify and localize intercalated DOX in isolated double-stranded calf thymus DNA, and the correlated near-field spectroscopic and morphologic experiments locate the DOX molecules in the DNA and provide further information regarding specific DOX-nucleobase interactions. Thus, the study provides a tool specifically for identifying intercalation markers and generally analyzing drug-DNA interactions. The structure of such complexes down to the molecular level provides mechanistic information about cytotoxicity and the development of potential anticancer drugs.

A novel doxorubicin/CTLA-4 blocker co-loaded drug delivery system improves efficacy and safety in antitumor therapy

Doxorubicin's antitumor effectiveness may be constrained with ineffective tumor penetration, systemic adverse effects, as well as drug resistance. The co-loading of immune checkpoint inhibitors and doxorubicin into liposomes can produce synergistic benefits and address problems, including quick drug clearance, toxicity, and low drug penetration efficiency. In our previous study, we modified a nanobody targeting CTLA-4 onto liposomes (LPS-Nb36) to be an extremely potent CTLA-4 signal blocker which improve the CD8+ T-cell activity against tumors under physiological conditions. In this study, we designed a drug delivery system (LPS-RGD-Nb36-DOX) based on LPS-Nb36 that realized the doxorubicin and anti-CTLA-4 Nb co-loaded and RGD modification, and was applied to antitumor therapy. We tested whether LPS-RGD-Nb36-DOX could targets the tumor by in vivo animal photography, and more importantly, promote cytotoxic T cells proliferation, pro-inflammatory cytokine production, and cytotoxicity. Our findings demonstrated that the combination of activated CD8+ T cells with doxorubicin/anti-CTLA-4 Nb co-loaded liposomes can effectively eradicate tumor cells both in vivo and in vitro. This combination therapy is anticipated to have synergistic antitumor effects. More importantly, it has the potential to reduce the dose of chemotherapeutic drugs and improve safety.

Comparison of bolus administration and short-term infusion versus long-term infusion of doxorubicin in terms of cardiotoxicity and efficacy

Cardiotoxicity caused by anthracyclines chemotherapy is one of the leading causes of mortality and morbidity in cancer survivors. Continuous infusion (CI) instead of bolus (BOL) injection is one of the methods that seem to be effective in reducing doxorubicin (DOX) cardiotoxicity. Due to the variety of results, we decided to compare these two approaches regarding toxicity and efficacy and report the final results for different cancers. We included 21 studies (four preclinical and seventeen clinical trials) up to May 15, 2023. In children with acute lymphoblastic leukemia (ALL) and adults with chronic lymphoblastic leukemia (CLL) and gastric cancer, results were in favor of BOL injection, without increase in cardiotoxicity. On the other hand, CI showed to be better option in patients with small-cell lung cancer (SCLC) and breast cancer. Various results were also observed in adult patients with sarcoma. Overall, it can be concluded that the benefits of CI, especially in adults, outweigh its disadvantages. However, due to the variety of results and heterogeneity of studies, further clinical trials with a larger sample size and a longer duration of follow-up are needed to make a more accurate comparison between CI and BOL injection.

Doxorubicin concentrations in bone tumour-relevant tissues after bolus and continuous infusion: a randomized porcine microdialysis study

PURPOSE

Doxorubicin is a widely used chemotherapeutic drug that can be administered intravenously as both a bolus infusion and a continuous infusion. The latter is believed to lower the risk of cardiotoxicity, which is a critical long-term complication of doxorubicin treatment. The local tissue concentrations of doxorubicin will be reflected in both treatment efficacy and toxicity, but very limited information is available. The aim of this study was to measure the concentration of doxorubicin after continuous and bolus infusion in tissue compartments around a typical location of a bone tumour.

METHODS

Sixteen pigs (female, Danish Landrace, mean weight 77 kg) were randomized into two groups of eight. Both groups received an intravenous infusion of 150 mg doxorubicin; Group 1 received a bolus infusion (10-15 min) and Group 2 received a continuous infusion (6 h). Before infusion, microdialysis catheters were placed intravenously and in four bone tumour-relevant tissue compartments (cancellous bone, subcutaneous tissue, synovial fluid of the knee joint and muscle tissue). Sampling was done (n = 15) over 24 h, and venous blood samples were collected as a reference.

RESULTS

Area under the concentration-time curve (AUC0-24 h) for plasma (total concentration) was significantly different between the two groups, while peak drug concentration (Cmax) was significantly higher in two compartments (plasma and synovial fluid of the knee joint) in Group 1 compared to Group 2. Overall, the unbound tissue concentrations were extremely low with values below 0.20 µg/mL.

CONCLUSION

The pharmacokinetic profile for doxorubicin in the investigated tissues is very similar when comparing bolus and 6 h continuous infusion.

Nature-inspired substituted 3-(imidazol-2-yl) morpholines targeting human topoisomerase IIα: Dynophore-derived discovery

The molecular nanomachine, human DNA topoisomerase IIα, plays a crucial role in replication, transcription, and recombination by catalyzing topological changes in the DNA, rendering it an optimal target for cancer chemotherapy. Current clinical topoisomerase II poisons often cause secondary tumors as side effects due to the accumulation of double-strand breaks in the DNA, spurring the development of catalytic inhibitors. Here, we used a dynamic pharmacophore approach to develop catalytic inhibitors targeting the ATP binding site of human DNA topoisomerase IIα. Our screening of a library of nature-inspired compounds led to the discovery of a class of 3-(imidazol-2-yl) morpholines as potent catalytic inhibitors that bind to the ATPase domain. Further experimental and computational studies identified hit compound 17, which exhibited selectivity against the human DNA topoisomerase IIα versus human protein kinases, cytotoxicity against several human cancer cells, and did not induce DNA double-strand breaks, making it distinct from clinical topoisomerase II poisons. This study integrates an innovative natural product-inspired chemistry and successful implementation of a molecular design strategy that incorporates a dynamic component of ligand-target molecular recognition, with comprehensive experimental characterization leading to hit compounds with potential impact on the development of more efficient chemotherapies.

Mechanistic study of Huangqi Guizhi Wuwu decoction amelioration of doxorubicin-induced cardiotoxicity by reducing oxidative stress and inhibiting cellular pyroptosis

Huangqi Guizhi Wuwu Decoction (HQGZWWD) has shown promising potential in treating various cardiovascular diseases. This study aimed to elucidate the molecular basis and therapeutic role of HQGZWWD in the treatment of doxorubicin (DOX)-induced myocardial injury. The HPLC fingerprint of HQGZWWD was used to analyze the active components. A DOX-induced myocardial damage rat model was developed, and the therapeutic effects of HQGZWWD were evaluated using echocardiography, myocardial enzyme levels, and hematoxylin and eosin staining. Network pharmacology was used to screen treatment targets, and western blotting and immunohistochemistry were performed to assess cellular pyroptosis levels. Oxidative stress levels were measured using assay kits, and mitochondrial damage was examined using transmission electron microscopy. An in vitro model of DOX-induced cell damage was established, and treatment was administered using serum containing HQGZWWD and N-acetylcysteine (NAC). Oxidative stress levels were detected using assay kits and DCFH-DA, whereas cellular pyroptosis levels were assessed through WB, immunofluorescence, and ELISA assays. HQGZWWD ameliorated DOX-induced myocardial injury. Network pharmacology identified IL-1β and IL-18 as crucial targets. HQGZWWD downregulated the protein levels of the inflammatory factors IL-1β and IL-18, inhibited the expression of GSDMD-NT, and simultaneously suppressed the synthesis of Caspase-1, ASC, NLRP3, and Caspase-11. Additionally, HQGZWWD inhibited oxidative stress, and the use of NAC as an oxidative stress inhibitor resulted in significant inhibition of the GSDMD-NT protein in H9C2 cells. These findings highlight the myocardial protective effects of HQGZWWD by inhibiting oxidative stress and suppressing both canonical and non-canonical pyroptotic pathways.

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.

Mechanism of Daunomycin Intercalation into DNA from Enhanced Sampling Simulations

Daunomycin is a widely used anticancer drug, yet the mechanism underlying how it binds to DNA remains contested. 469 all-atom trajectories of daunomycin binding to the DNA oligonucleotide d(GCG CAC GTG CGC) were collected using weighted ensemble (WE)-enhanced sampling. Mechanistic insights were revealed through analysis of the ensemble of trajectories. Initially, the binding process involves a ubiquitous hydrogen bond between the DNA backbone and the NH3+ group on daunomycin. During the binding process, most trajectories exhibited similar structural changes to DNA, including DNA base pair rise, bending, and minor groove width changes. Variability within the ensemble of binding trajectories illuminates differences in the orientation of daunomycin as it initially intercalates; around 10% of trajectories needed minimal rearrangement from intercalation to reaching the fully bound configuration, whereas most needed an additional 1-5 ns to rearrange. The results here emphasize the utility of generating an ensemble of trajectories to discern biomolecular binding mechanisms.

Baicalin and Baicalein Enhance Cytotoxicity, Proapoptotic Activity, and Genotoxicity of Doxorubicin and Docetaxel in MCF-7 Breast Cancer Cells

Breast cancer is a major health concern and the leading cause of death among women worldwide. Standard treatment often involves surgery, radiotherapy, and chemotherapy, but these come with side effects and limitations. Researchers are exploring natural compounds like baicalin and baicalein, derived from the Scutellaria baicalensis plant, as potential complementary therapies. This study investigated the effects of baicalin and baicalein on the cytotoxic, proapoptotic, and genotoxic activity of doxorubicin and docetaxel, commonly used chemotherapeutic drugs for breast cancer. The analysis included breast cancer cells (MCF-7) and human endothelial cells (HUVEC-ST), to assess potential effects on healthy tissues. We have found that baicalin and baicalein demonstrated cytotoxicity towards both cell lines, with more potent effects observed in baicalein. Both flavonoids, baicalin (167 µmol/L) and baicalein (95 µmol/L), synergistically enhanced the cytotoxic, proapoptotic, and genotoxic activity of doxorubicin and docetaxel in breast cancer cells. In comparison, their effects on endothelial cells were mixed and depended on concentration and time. The results suggest that baicalin and baicalein might be promising complementary agents to improve the efficacy of doxorubicin and docetaxel anticancer activity. However, further research is needed to validate their safety and efficacy in clinical trials.

Heliorhodopsin-mediated light-modulation of ABC transporter

Heliorhodopsins (HeRs) have been hypothesized to have widespread functions. Recently, the functions for few HeRs have been revealed; however, the hypothetical functions remain largely unknown. Herein, we investigate light-modulation of heterodimeric multidrug resistance ATP-binding cassette transporters (OmrDE) mediated by Omithinimicrobium cerasi HeR. In this study, we classifiy genes flanking the HeR-encoding genes and identify highly conservative residues for protein-protein interactions. Our results reveal that the interaction between OcHeR and OmrDE shows positive cooperatively sequential binding through thermodynamic parameters. Moreover, light-induced OcHeR upregulates OmrDE drug transportation. Hence, the binding may be crucial to drug resistance in O. cerasi as it survives in a drug-containing habitat. Overall, we unveil a function of HeR as regulatory rhodopsin for multidrug resistance. Our findings suggest potential applications in optogenetic technology.

Early myocardial injury in children on doxorubicin for cancer chemotherapy: a cross-sectional study in a tertiary referral centre in Kenya

INTRODUCTION

Use of doxorubicin, an anthracycline chemotherapeutic agent has been associated with late-occurring cardiac toxicities. Detection of early-occurring cardiac effects of cancer chemotherapy is essential to prevent occurrence of adverse events including toxicity, myocardial dysfunction, and death.

OBJECTIVE

To investigate the prevalence of elevated cardiac troponin T (cTnT) and associated factors of myocardial injury in children on doxorubicin cancer chemotherapy.

METHODS

Design: A cross-sectional study.

SETTING AND SUBJECTS

A hospital-based study conducted on children aged 1-month to 12.4-years who had a diagnosis of cancer and were admitted at Kenyatta National Hospital (KNH).

INTERVENTIONS AND OUTCOMES

The patients underwent Echocardiography (ECHO) before their scheduled chemotherapy infusion. Twenty-four (24) hours after the chemotherapy infusion the patients had an evaluation of the serum cardiac troponin T (cTnT) and a repeat ECHO. Myocardial injury was defined as cTnT level > 0.014 ng/ml or a Fractional Shortening (FS) of < 29% on ECHO.

RESULTS

One hundred (100) children were included in the final analysis. Thirty-two percent (32%) of the study population had an elevated cTnT. A cumulative doxorubicin dose of > 175 mg/m2 was significantly associated with and elevated cTnT (OR, 10.76; 95% CI, 1.18-97.92; p = 0.035). Diagnosis of nephroblastoma was also associated with an elevated cTnT (OR, 3.0; 95% CI, 1.23-7.26) but not statistically significant (p = 0.105). Nine percent (9%) of the participants had echocardiographic evidence of myocardial injury.

CONCLUSION

When compared to echocardiography, elevated levels of cTnT showed a higher association with early-occurring chemotherapy-induced myocardial injury among children on cancer treatment at a tertiary teaching and referral hospital in Kenya.

Diverse Combinatorial Biosynthesis Strategies for C-H Functionalization of Anthracyclinones

Streptomyces spp. are "nature's antibiotic factories" that produce valuable bioactive metabolites, such as the cytotoxic anthracycline polyketides. While the anthracyclines have hundreds of natural and chemically synthesized analogues, much of the chemical diversity stems from enzymatic modifications to the saccharide chains and, to a lesser extent, from alterations to the core scaffold. Previous work has resulted in the generation of a BioBricks synthetic biology toolbox in Streptomyces coelicolor M1152ΔmatAB that could produce aklavinone, 9-epi-aklavinone, auramycinone, and nogalamycinone. In this work, we extended the platform to generate oxidatively modified analogues via two crucial strategies. (i) We swapped the ketoreductase and first-ring cyclase enzymes for the aromatase cyclase from the mithramycin biosynthetic pathway in our polyketide synthase (PKS) cassettes to generate 2-hydroxylated analogues. (ii) Next, we engineered several multioxygenase cassettes to catalyze 11-hydroxylation, 1-hydroxylation, 10-hydroxylation, 10-decarboxylation, and 4-hydroxyl regioisomerization. We also developed improved plasmid vectors and S. coelicolor M1152ΔmatAB expression hosts to produce anthracyclinones. This work sets the stage for the combinatorial biosynthesis of bespoke anthracyclines using recombinant Streptomyces spp. hosts.

Prevention and treatment of anthracycline-induced cardiotoxicity: A bibliometric analysis of the years 2000-2023

Aims

This study aimed to evaluate the global research trend in the prevention and treatment of cardiotoxicity caused by anthracyclines from 2000 to 2023, and to explore international cooperation, research hotspots, and frontier trends.

Methods

The articles on the prevention and treatment of anthracycline-induced cardiotoxicity published from 2000 to 2023 were searched by Web of Science. The bibliometrics software CiteSpace was used for visual analysis of countries, institutions, journals, authors, cited authors, cited references, and keywords.

Results

This study analyzed the current status of global research on the prevention and treatment of cardiotoxicity caused by anthracyclines. A total of 3,669 papers were searched and 851 studies were included. The number of publications increased gradually throughout the years. Cardiovascular Toxicology (15) is the journal with the most publications. Circulation (547) ranked first among cited journals. In this field, the country with the most publications is the United States (229), and the institution with the most publications is Charles Univ Prague (18). In the analysis of the authors, Tomas S (10) ranked first. Cardinale D (262) ranked first among cited authors. In the ranking of cited literature frequency, the article ranked first is "Early detection of anthracycline cardiotoxicity and improvement with heart failure therapy" (121). The keywords "heart failure" (215) and "oxidative stress" (212) were the most frequent. "Enalapril", "inflammation", "cell death", "NF-κB" and "Nrf2" were the advanced research contents in 2019-2023.

Conclusions

This study provided valuable information for cardio-oncology researchers to identify potential collaborators and institutions, discover hot topics, and explore new research directions. The prevention and treatment of anthracycline-induced cardiotoxicity focuses on early detection and timely treatment. The results of the current clinical studies on the treatment of anthracycline-induced cardiotoxicity are contradictory, and more studies are needed to provide more reliable clinical evidence in the future.

Codelivery of Doxorubicin and p53 Gene by β-Cyclodextrin-Based Supramolecular Nanoparticles Formed via Host-Guest Complexation and Electrostatic Interaction

We developed a supramolecular system for codelivery of doxorubicin (Dox) and p53 gene based on a β-CD-containing star-shaped cationic polymer. First, a star-shaped cationic polymer consisting of a β-CD core and 3 arms of oligoethylenimine (OEI), named CD-OEI, was used to form a supramolecular inclusion complex with hydrophobic Dox. The CD-OEI/Dox complex was subsequently used to condense plasmid DNA via electrostatic interactions to form CD-OEI/Dox/DNA polyplex nanoparticles with positive surface charges that enhanced the cellular uptake of both Dox and DNA. This supramolecular drug and gene codelivery system showed high gene transfection efficiency and effective protein expression in cancer cells. The codelivery of Dox and DNA encoding the p53 gene resulted in reduced cell viability and enhanced antitumor effects at low Dox concentrations. With its enhanced cellular uptake and anticancer efficacy, the system holds promise as a delivery carrier for potential combination cancer therapies.

Alanyl-tRNA synthetase, AARS1, is a lactate sensor and lactyltransferase that lactylates p53 and contributes to tumorigenesis

Lysine lactylation is a post-translational modification that links cellular metabolism to protein function. Here, we find that AARS1 functions as a lactate sensor that mediates global lysine lacylation in tumor cells. AARS1 binds to lactate and catalyzes the formation of lactate-AMP, followed by transfer of lactate to the lysince acceptor residue. Proteomics studies reveal a large number of AARS1 targets, including p53 where lysine 120 and lysine 139 in the DNA binding domain are lactylated. Generation and utilization of p53 variants carrying constitutively lactylated lysine residues revealed that AARS1 lactylation of p53 hinders its liquid-liquid phase separation, DNA binding, and transcriptional activation. AARS1 expression and p53 lacylation correlate with poor prognosis among cancer patients carrying wild type p53. β-alanine disrupts lactate binding to AARS1, reduces p53 lacylation, and mitigates tumorigenesis in animal models. We propose that AARS1 contributes to tumorigenesis by coupling tumor cell metabolism to proteome alteration.