Concentrations Of Doxorubicin Research Articles

Establishment and Characterization of Multi-Drug Resistant p53-Negative Osteosarcoma SaOS-2 Subline.

To establish a p53-negative osteosarcoma (OS) SaOS-2 cellular subline exhibiting resistance to specific chemotherapeutic agents, including topoisomerase II inhibitors, taxanes, and vinca alkaloids. The OS subline exhibiting resistance to the chemotherapeutic agents indicated above was generated by the stepwise treatment of the parental SaOS-2 cell line with increasing concentrations of doxorubicin (Dox) for 5 months. Half-inhibitory concentrations (IC50) for Dox, vinblastine (Vin), and paclitaxel (PTX) were calculated by a colorimetric MTS-based assay. Crystal violet staining was used to assess cellular viability, whereas the proliferation capacities of cancer cells were monitored in real-time by the i-Celligence system. Expression of apoptotic markers (e.g., cleaved PARP and caspase-3), DNA repair proteins (e.g., ATM, DNA-PK, Nbs1, Rad51, MSH2, etc.), and certain ABC transporters (P-glycoprotein, MRP1, ABCG2, etc.) was assessed by western blotting and real-time PCR. Flow cytometry was used to examine the fluorescence intensity of Dox and ABC-transporter substrates (e.g., Calcein AM and CMFDA) and to assess their excretion to define the activity of specific ABC-transporters. To confirm OS resistance to Dox in vivo, xenograft experiments were performed. An OS subline generated by a stepwise treatment of the parental SaOS-2 cell line with increasing concentrations of Dox resulted in an increase in the IC50 for Dox, Vin, and PTX (~6-, 4-, and 30-fold, respectively). The acquisition of chemoresistance in vitro was also evidenced by the lack of apoptotic markers (e.g., cleaved PARP and caspase-3) in resistant OS cells treated with the chemotherapeutic agents indicated above. The development of the multidrug resistance (MDR) phenotype in this OS subline was due to the overexpression of ABCB1 (i.e., P-glycoprotein) and ABCC1 (i.e., multidrug resistance protein-1, MRP-1), which was evidenced on both mRNA and protein levels. Due to increased expression of MDR-related proteins, resistant OS exhibited an excessive efflux of Dox. Moreover, decreased accumulation of calcein AM, a well-known fluorescent substrate for both ABCB1 and ABCC1, was observed for resistant OS cells compared to their parental SaOS-2 cell line. Importantly, tariquidar and cyclosporin, well-known ABC inhibitors, retained the intensity of Dox-induced fluorescence in resistant SAOS-2 cells. Furthermore, in addition to the increased efflux of the chemotherapeutic agents from Dox-resistant OS cells, we found higher expression of several DNA repair proteins (e.g., Rad51 recombinase, Mre11, and Nbs1, activated forms of ATM, DNA-PK, Chk1, and Chk2, etc.), contributing to the chemoresistance due to the excessive DNA repair. Lastly, the in vivo study indicated that Dox has no impact on the SaOS-2 Dox-R xenograft tumor growth in a nude mouse model. An acquired resistance of OS to the chemotherapeutic agents might be due to the several mechanisms undergoing simultaneously on the single-cell level. This reveals the complexity of the mechanisms involved in the secondary resistance of OS to chemotherapies.

Abstract P2175: Induced Pluripotent Stem Cell-derived Cardiac Myocytes To Assess Anthracycline Cardiotoxicity

Background: Anthracyclines are a class of highly effective chemotherapeutics, yet their use is regularly complicated by anthracycline-induced cardiotoxicity (AIC). The advent of induced pluripotent stem cell-derived cardiac myocytes (iPSC-CMs) offers the potential for disease modeling and prediction of genetic cardiomyopathies. Purpose: We aim to use iPSC-CMs to assess susceptibility to AIC. Methods: Five AIC heart transplant patients and five anthracycline treated patients without AIC were included in our study. We reprogrammed lymphocytes from both groups toward iPSCs using Sendai Virus, followed by differentiation into CM-like cells. Cytotoxicity following chemotherapy exposure was assessed using flow cytometry (FC), electron microscopy (EM) and reactive oxygen species generation (ROS). Furthermore, whole genome sequencing (WGS) was performed and variants were filtered based on allele frequency, pathogenicity using HumVar trained variant effect predictors and presence in patients versus controls. Results: The cytotoxic effect of increasing concentrations of doxorubicin was quantifiable using FC on SIRPA positive iPSC-CMs ( A ). There was a higher rate of cell death at any concentration of doxorubicin in patients with AIC as opposed to controls ( B ). On the ultrastructural level, doxorubicin treated iPSC-CMs manifested darker and more condensed mitochondria as seen with EM ( C ). Increased ROS production was observed following doxorubicin exposure ( D ). WGS analysis showed 2 pathogenic variants in the PRAMEF6 gene present in cases and not in controls ( E ). Conclusion: iPSC-CMs represent a robust disease model to study mechanisms of and susceptibility to AIC.

Delicate Hybrid Laponite-Cyclic Poly(ethylene glycol) Nanoparticles as a Potential Drug Delivery System.

The objective of the study was to explore the feasibility of a new drug delivery system using laponite (LAP) and cyclic poly(ethylene glycol) (cPEG). Variously shaped and flexible hybrid nanocrystals were made by both the covalent and physical attachment of chemically homogeneous cyclized PEG to laponite nanodisc plates. The size of the resulting, nearly spherical particles ranged from 1 to 1.5 µm, while PEGylation with linear methoxy poly (ethylene glycol) (mPEG) resulted in fragile sheets of different shapes and sizes. When infused with 10% doxorubicin (DOX), a drug commonly used in the treatment of various cancers, the LAP-cPEG/DOX formulation was transparent and maintained liquid-like homogeneity without delamination, and the drug loading efficiency of the LAP-cPEG nano system was found to be higher than that of the laponite-poly(ethylene glycol) LAP-mPEG system. Furthermore, the LAP-cPEG/DOX formulation showed relative stability in phosphate-buffered saline (PBS) with only 15% of the drug released. However, in the presence of human plasma, about 90% of the drug was released continuously over a period of 24 h for the LAP-cPEG/DOX, while the LAP-mPEG/DOX formulation released 90% of DOX in a 6 h burst. The results of the cell viability assay indicated that the LAP-cPEG/DOX formulation could effectively inhibit the proliferation of A549 lung carcinoma epithelial cells. With the DOX concentration in the range of 1-2 µM in the LAP-cPEG/DOX formulation, enhanced drug effects in both A549 lung carcinoma epithelial cells and primary lung epithelial cells were observed compared to LAP-mPEG/DOX. The unique properties and effects of cPEG nanoparticles provide a potentially better drug delivery system and generate interest for further targeting studies and applications.

Non-interference delivery of Ce6 and DOX in NIR light-responsive liposomes for synergetic cervical cancer therapy

Multi-model combination treatment of malignant tumors can make up for the shortcomings of single treatment through multi-target and multi-path to achieve more ideal tumor treatment effect. However, the mutual interference of different drugs in the delivery process in vivo and the difficulty of effective drug accumulation in tumor cells are the bottlenecks of combined therapy. To this project, light-responsive liposomes loading doxorubicin (DOX) and chlorin e6 (Ce6) (DOX-Ce6-Lip) without mutual interference were engineered by thin film hydration method. This kind of nano-drug delivery system increased the drugs concentration accumulated in tumor sites through enhanced permeability and retention effect, and reduced the toxic and side effects of drugs on normal tissues in vivo. In addition, after entering the tumor cells, Ce6 produced a large number of reactive oxygen species under 660 nm NIR laser irradiation, which further oxidized the unsaturated fatty acid chain in the liposomes and caused the collapse of the liposomes, thus realizing the stimulus-responsive release of Ce6 and DOX. The concentrations of DOX and Ce6 in the tumor cells rapidly reached the peak and achieved a more effective combination of chemotherapy and photodynamic therapy (PDT). Consequently, DOX-Ce6-Lip followed by 660 nm NIR irradiation achieved an efficient tumor growth inhibition of 71.90 ± 3.14%, indicating the versatile potential of chemotherapy and PDT. In conclusion, this study provides a delivery scheme for drugs with different solubilities and an effectively combined anti-tumor therapy method.

Inhibition of multiple uptake transporters in cardiomyocytes/mitochondria alleviates doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) has been widely used to treat various tumors; however, DOX-induced cardiotoxicity limits its utilization. Since high accumulation of DOX in cardiomyocytes/mitochondria is the key reason, we aimed to clarify the mechanisms of DOX uptake and explore whether selectively inhibiting DOX uptake transporters would attenuate DOX accumulation and cardiotoxicity. Our results demonstrated that OCTN1/OCTN2/PMAT (organic cation/carnitine transporter 1/2 or plasma membrane monoamine transporter), especially OCTN2, played crucial roles in DOX uptake in cardiomyocytes, while OCTN2 and OCTN1 contributed to DOX transmembrane transport in mitochondria. Metformin (1–100 μM) concentration-dependently reduced DOX (5 μM for accumulation, 500 nM for cytotoxicity) concentration and toxicity in cardiomyocytes/mitochondria via inhibition of OCTN1-, OCTN2- and PMAT-mediated DOX uptake but did not affect its efflux. Furthermore, metformin (iv: 250 and 500 mg/kg or ig: 50, 100 and 200 mg/kg) could dose-dependently reduce DOX (8 mg/kg) accumulation in mouse myocardium and attenuated its cardiotoxicity. In addition, metformin (1–100 μM) did not impair DOX efficacy in breast cancer or leukemia cells. In conclusion, our study clarified the role of multiple transporters, especially OCTN2, in DOX uptake in cardiomyocytes/mitochondria; metformin alleviated DOX-induced cardiotoxicity without compromising its antitumor efficacy by selective inhibition of multiple transporters mediated DOX accumulation in myocardium/mitochondria.

Bioactive Bacteria/MOF Hybrids Can Achieve Targeted Synergistic Chemotherapy and Chemodynamic Therapy against Breast Tumors

AbstractThe hypoxic tumor microenvironment (TME) significantly affects cancer treatment. Conventional chemotherapeutic agents cannot effectively target hypoxic tumor tissue, which decreases efficacy and results in severe toxic side effects. To alleviate this problem, a self‐driving biomotor is developed by functionalizing MCDP nanoparticles containing calcium peroxide and doxorubicin (DOX) loaded onto polydopamine‐coated metal–organic frameworks（MOF）, with the anaerobic Bifidobacterium infantis (Bif) for synergistic chemotherapy and chemodynamic therapy (CDT) against breast cancer. The materials of institute Lavoisier (MIL) frameworks + CaO2 + DOX + polydopamine (MCDP)@Bif biohybrid actively targets hypoxic regions of solid tumors via the inherent targeting ability of Bif. Once it has accumulated in the tumor tissue, MCDP generates hydroxyl radicals through the enhanced Fenton‐type reactions between Fe2+ and self‐generated hydrogen peroxide in the acidic TME. The disruption of Ca2+ homeostasis and resulting mitochondrial Ca2+ overload triggers apoptosis and enhances oxidative stress, promoting tumor cell death. The results found that the DOX concentration in MCDP@Bif‐treated tumors is 3.8 times higher than that in free‐DOX‐treated tumors, which significantly prolongs the median survival of the tumor‐bearing mice to 69 days and reduces the toxic side effects of DOX. Therefore, the novel bacteria‐driven drug delivery system is highly effective in achieving synergistic chemotherapy and CDT against solid tumors.

A tumor-specific ROS self-supply enhanced cascade-responsive prodrug activation nanosystem for amplified chemotherapy against multidrug-resistant tumors.

Chemotherapy remains the mainstay of cancer treatment, and doxorubicin (DOX) is recommended as a first-line chemotherapy drug against cancer. However, systemic adverse drug reactions and multidrug resistance limit its clinical applications. Here, a tumor-specific reactive oxygen species (ROS) self-supply enhanced cascade responsive prodrug activation nanosystem (denoted as PPHI@B/L) was developed to optimize multidrug resistance tumor chemotherapy efficacy while minimizing the side effects. PPHI@B/L was constructed by encapsulating the ROS-generating agent β-lapachone (Lap) and the ROS-responsive doxorubicin prodrug (BDOX) in acidic pH-sensitive heterogeneous nanomicelles. PPHI@B/L exhibited particle size decrease and charge increase when it reached the tumor microenvironment due to acid-triggered PEG detachment, to favor its endocytosis efficiency and deep tumor penetration. Furthermore, after PPHI@B/L internalization, rapidly released Lap was catalyzed by the overexpressed quinone oxidoreductase-1 (NQO1) enzyme NAD(P)H in tumor cells to selectively raise intracellular ROS levels. Subsequently, ROS generation further promoted the specific cascade activation of the prodrug BDOX to exert the chemotherapy effects. Simultaneously, Lap-induced ATP depletion reduced drug efflux, synergizing with increased intracellular DOX concentrations to assist in overcoming multidrug resistance. This tumor microenvironment-triggered cascade responsive prodrug activation nanosystem potentiates antitumor effects with satisfactory biosafety, breaking the chemotherapy limitation of multidrug resistance and significantly improving therapy efficiency. STATEMENT OF SIGNIFICANCE: Chemotherapy remains the mainstay of cancer treatment, and doxorubicin (DOX) is recommended as a first-line chemotherapy drug against cancer. However, systemic adverse drug reactions and multidrug resistance limit its clinical applications. Here, a tumor-specific reactive oxygen species (ROS) self-supply enhanced cascade responsive prodrug activation nanosystem (denoted as PPHI@B/L) was developed to optimize multidrug resistance tumor chemotherapy efficacy while minimizing the side effects. The work provides a new sight for simultaneously addressing the molecular mechanisms and physio-pathological disorders to overcome MDR in cancer treatment.

Electrochemical sensing of doxorubicin hydrochloride under sodium alginate antifouling conditions using silver nanoparticles modified glassy carbon electrodes

Doxorubicin (DOX) is a highly effective anticancer drug with a narrow therapeutic window; thus, sensitive and timely detection of DOX is crucial. Using electrodeposition of silver nanoparticles (AgNPs) and electropolymerization of alginate (Alg) layers on the surface of a glassy carbon electrode, a novel electrochemical probe was constructed (GCE). The fabricated AgNPs/poly-Alg-modified GCE probe was utilized for the quantification of DOX in unprocessed human plasma samples. For the electrodeposition of AgNPs and electropolymerization of alginate (Alg) layers on the surface of GCE, cyclic voltammetry (CV) was used in the potential ranges of −2.0 to 2.0 V and −0.6 to 0.2 V, respectively. The electrochemical activity of DOX exhibited two oxidation processes at the optimum pH value of 5.5 on the surface of the modified GCE. The DPV spectra of poly(Alg)/AgNPs modified GCE probe toward consecutive concentrations of DOX in plasma samples demonstrated wide dynamic ranges of 15 ng/mL-0.1 μg/mL and 0.1–5.0 μg/mL, with a low limit of quantification (LLOQ) of 15 ng/mL. The validation results indicated that the fabricated electrochemical probe might serve as a highly sensitive and selective assay for the quantification of DOX in patient samples. As an outstanding feature, the developed probe could detect DOX in unprocessed plasma samples and cell lysates without the requirement for pretreatment.

PEG-liposomal doxorubicin as a potential agent for canine metastatic osteosarcoma - in vitro and ex ovo studies.

Appendicular osteosarcoma (OSA) is a highly aggressive and metastatic primary bone tumour in dogs. Standard therapy is amputation and adjuvant chemotherapy (e.g. with doxorubicin). Liposomal drug delivery may augment therapeutic efficacy and reduce negative side effects. Polyethylene glycol (PEG)-liposomal doxorubicin treats human metastatic cancers effectively. The study aimed was to evaluate PEG-liposomal doxorubicin's inhibitory effect on canine metastatic proliferation and migration in vitro. It also aimed to appraise the drug's extravasation inhibition in vivo using the human medicine-proven chick embryo chorioallantoic membrane ex ovo model. The canine D-17 OSA cell line was cultured and inoculated with decreasing concentrations of PEG-liposomal doxorubicin and conventional doxorubicin in a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) test of cell viability, proliferation and cytotoxicity. Flow cytometry with Annexin V and Draq 7 staining confirmed the MTT test results, indicating dead, early and late apoptotic, and live cells. The inhibitory effect of the two preparations on cancer cell migration was investigated with a wound-healing assay. Culture plates seeded with cells were prepared. The cell monolayer was scratched and images of cells migrating to the scratch were captured at 0 h, 12 h and 24 h. Also, embryos were removed from three-day-incubated fertilised chicken eggs. On the 12th day, labelled D-17 cells were injected into each embryo. Embryos in one group received 100 μL of phosphate-buffered saline as controls, those in another group 30 μg/mL of PEG-liposomal doxorubicin, and those in the last group 6 μg/mL of conventional doxorubicin. The effectiveness of the intravascular administration of the D-17 cells was confirmed under a microscope. PEG-liposomal doxorubicin inhibited the migration of canine OSA cells more effectively than conventional doxorubicin (P ≤ 0.05). The ex ovo model showed that both drugs had similar impacts on canine metastatic OSA. The liposomal form of the drug may be considered a potentially effective compound in canine metastatic OSA; nevertheless, further in vivo studies are essential to confirm this hypothesis.

Development and validation of a UPLC-MS/MS method for simultaneous detection of doxorubicin and sorafenib in plasma: Application to pharmacokinetic studies in rats

An ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the simultaneous quantitation of doxorubicin (DOX) and sorafenib (SOR) in rat plasma. Chromatographic separation was performed using a reversed-phase column C18 (1.7 μm, 1.0 × 100 mm Acquity UPLC BEH™). The gradient mobile phase system consisted of water containing 0.1% acetic acid (mobile phase A) and methanol (mobile phase B) with a flow rate of 0.40 mL/min over 8 min. Erlotinib (ERL) was used as an internal standard (IS). The quantitation of conversion of [M + H]+, which was the protonated precursor ion, to the corresponding product ions was performed using multiple reaction monitoring (MRM) with a mass-to-charge ratio (m/z) of 544 > 397.005 for DOX, 465.05 > 252.03 for SOR, and 394 > 278 for the IS. Different parameters were used to validate the method including accuracy, precision, linearity, and stability. The developed UPLC–MS/MS method was linear over the concentration ranges of 9–2000 ng/mL and 7–2000 ng/mL with LLOQ of 9 and 7 ng/mL for DOX and SOR, respectively. The intra-day and inter-day accuracy, expressed as % relative standard deviation (RSD%), was below 10% for both DOX and SOR in all QC samples that have drug concentrations above the LLOQ. The intra-day and inter-day precision, expressed as percent relative error (Er %), was within the limit of 15.0% for all concentrations above LLOQ. Four groups of Wistar rats (250–280 g) were used to conduct the pharmacokinetic study. Group I received a single intraperitoneal (IP) injection of DOX (5 mg/kg); Group II received a single oral dose of SOR (40 mg/kg), Group III received a combination of both drugs; and Group IV received sterile water for injection IP and 0.9% w/v sodium chloride solution orally to serve as a control. Non-compartmental analysis was used to calculate the different pharmacokinetic parameters. Data revealed that coadministration of DOX and SOR altered some of the pharmacokinetic parameters of both agents and resulted in an increase in the Cmax and AUC and reduction in the apparent clearance (CL/F). In conclusion, our newly developed method is sensitive, specific, and can reliably be used to simultaneously determine DOX and SOR concentrations in rat plasma. Moreover, the results of the pharmacokinetic study suggest that coadministration of DOX and SOR might cause an increase in exposure of both drugs.

P64 | CardioDox: Towards development of a personalized physiologically based pharmacokinetic model to predict cardiac doxorubicin concentrations in dogs

Journal of Veterinary Pharmacology and TherapeuticsVolume 46, Issue S1 p. 116-116 POSTER PRESENTATIONS P64 | CardioDox: Towards development of a personalized physiologically based pharmacokinetic model to predict cardiac doxorubicin concentrations in dogs First published: 11 June 2023 https://doi.org/10.1111/jvp.13343Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. Volume46, IssueS1Special Issue: 15th International Congress of the European Association for Veterinary Pharmacology and Toxicology held Bruges, Belgium, July 2–5, 2023June 2023Pages 116-116 RelatedInformation

Synergistic cytotoxic effects of an extremely low-frequency electromagnetic field with doxorubicin on MCF-7 cell line

Breast cancer is one of the leading causes of cancer deaths in women worldwide. Magnetic fields have shown anti-tumor effects in vitro and in vivo as a non-invasive therapy method that can affect cellular metabolism remotely. Doxorubicin (DOX) is one of the most commonly used drugs for treating breast cancer patients. It can be assumed that combining chemotherapy and magnetotherapy is one of the most effective treatments for breast cancer. This study aimed to investigate the potential cytotoxic effect of DOX at low concentrations in combination with extremely low-frequency electromagnetic fields (ELF–EMF; 50 Hz; 20 mT). The breast cancer cell line MCF-7 was examined for oxidative stress, cell cycle, and apoptosis. MCF-7 cells were treated with various concentrations of DOX as an apoptosis-inducing agent and ELF–EMF. Cytotoxicity was examined using the MTT colorimetric assay at 12, 24, and 48 h. Consequently, concentration- and time-dependent cytotoxicity was observed in MCF-7 cells for DOX within 24 h. The MTT assay results used showed that a 2 μM concentration of DOX reduced cell viability to 50% compared with control, and as well, the combination of ELF–EMF and DOX reduced cell viability to 50% compared with control at > 0.25 μM doses for 24 h. In MCF-7 cells, combining 0.25 μM DOX with ELF–EMF resulted in increased ROS levels and DOX-induced apoptosis. Flow cytometry analysis, on the other hand, revealed enhanced arrest of MCF-7 cells in the G0-G1 phase of the cell cycle, as well as inducing apoptotic cell death in MCF-7 cells, implying that the synergistic effects of 0.25 μM DOX and ELF–EMF may represent a novel and effective agent against breast cancer.

Fluorescent Alloyed CdZnSeS/ZnS Nanosensor for Doxorubicin Detection

Doxorubicin (DOX) is widely used in chemotherapy as an anti-tumor drug. However, DOX is highly cardio-, neuro- and cytotoxic. For this reason, the continuous monitoring of DOX concentrations in biofluids and tissues is important. Most methods for the determination of DOX concentrations are complex and costly, and are designed to determine pure DOX. The purpose of this work is to demonstrate the capabilities of analytical nanosensors based on the quenching of the fluorescence of alloyed CdZnSeS/ZnS quantum dots (QDs) for operative DOX detection. To maximize the nanosensor quenching efficiency, the spectral features of QDs and DOX were carefully studied, and the complex nature of QD fluorescence quenching in the presence of DOX was shown. Using optimized conditions, turn-off fluorescence nanosensors for direct DOX determination in undiluted human plasma were developed. A DOX concentration of 0.5 µM in plasma was reflected in a decrease in the fluorescence intensity of QDs, stabilized with thioglycolic and 3-mercaptopropionic acids, for 5.8 and 4.4 %, respectively. The calculated Limit of Detection values were 0.08 and 0.03 μg/mL using QDs, stabilized with thioglycolic and 3-mercaptopropionic acids, respectively.

METTL3-mediated m6A modification of lnc KCNQ1OT1 promotes doxorubicin resistance in breast cancer by regulating miR-103a-3p/MDR1 axis

ABSTRACT Doxorubicin (DOX) resistance in breast cancer (BC) poses a huge challenge for the therapeutic effect on BC. Lnc KCNQ1OT1 play crucial roles in chemotherapy resistance. However, the role and mechanism of lnc KCNQ1OT1 in DOX resistance BC have not been investigated, which merits further exploration. Based on MCF‐7 and MDA-MB-231 cells, MCF‐7/DOX and MDA-MB-231/DOX cells were established using gradient concentrations of DOX. IC50 values and cell viability were determined using MTT. Cell proliferation was investigated by colony formation. Flow cytometry was performed to examine cell apoptosis and cell cycle. Gene expression was examined using qRT-PCR and western blot. The interactions among METTL3, lnc KCNQ1OT1, miR-103a-3p, and MDR1 were validated with MeRIP-qPCR, RIP, and dual-luciferase reporter gene assays. The results showed that Lnc KCNQ1OT1 was highly expressed in DOX-resistant BC cells, and lnc KCNQ1OT1 depletion could enhance DOX sensitivity in BC cells and DOX-resistant BC cells. Besides, lnc KCNQ1OT1 was modulated by MELLT3 in the manner of m6A modification. MiR-103a-3p could interact with lnc KCNQ1OT1 and MDR1. Overexpression of MDR1 abolished the impacts of lnc KCNQ1OT1 depletion on DOX resistance in BC. In conclusion, our results unveiled that in BC cells and DOX-resistant BC cells, lnc KCNQ1OT1 could be mediated by METTL3 through m6A modification to elevate and stabilize its expression, further inhibitingmiR-103a-3p/MDR1 axis to promote DOX resistance, which might provide novel thought to overcome DOX resistance in BC.

Unsaturated free fatty acid emulsion infusion into carotid artery enhances drug delivery to the rat brain.

To determine whether the blood-brain barrier (BBB) opens to enhance drug delivery during the acute stage of unsaturated fat embolism. We infused oleic, linoleic, and linolenic acid emulsions through the right common carotid artery of rats, followed by trypan blue for gross and lanthanum for electron microscopic (EM) examination. Doxorubicin and temozolomide were also administered, and then the rats were euthanized at 30min, 1h, and 2h. Trypan blue hue was analyzed to semiquantitatively measure BBB opening. Desorption electrospray ionization-mass spectrometry (DESI-MS) imaging was used to evaluate drug delivery. Trypan blue staining observed in each group 30min after emulsion infusion increased at 1h and decreased after 2h in the oleic acid group. The linoleic and linolenic acid groups showed weak staining over time. The hue and trypan blue analysis results were corroborative. EM showed tight junction opening, whereas DESI-MS imaging showed increased doxorubicin and temozolomide signal intensities in ipsilateral hemispheres of all three groups. We demonstrated that oleic, linoleic, and linolenic acid emulsions opened the BBB, promoting drug delivery to the brain. Hue analysis and DESI-MS imaging are appropriate for analysis of doxorubicin and temozolomide concentrations in brain tissue.

C7 COMBINATION OF SPIRULINA, GANODERMA LUCIDUM AND MORINGA OLEIFERA IMPROVES CARDIAC FUNCTIONS AND REDUCES PRO–INFLAMMATORY BIOMARKERS IN PRECLINICAL MODELS OF SHORT–TERM DOXORUBICIN–MEDIATED CARDIOTOXICITY

Abstract Background Anthracyclines are essential adjuvant therapies for a variety of cancers, particularly breast, and gastric and esophageal cancers. Whilst prolonging cancer–related survival, these agents can in–duce drug–related cardiotoxicity. Spirulina, Reishi (Ganoderma Lucidum) and Moringa are three nutaceuticals with anti–inflammatory effects that are currently used in cancer patients to improve quality of life and fatigue. Methods Female C57Bl/6 mice were untreated (Sham, n=6) or treated for 10 days with short–term doxorubicin i.p at 2.17 mg/kg (DOXO, n=6), Singo at 12 mg/kg (Singo, n=6) or doxorubicin combined to Singo (DOXO–Singo, n=6). Ejection fraction, radial and longitudinal strain were analyzed through transthoracic echocardiography (Vevo 2100, Fujifilm). Myocardial expression of NLRP3, DAMPs (galectine 3 and calgranulin S100) and 13 cytokines (IL–1α, IL–1β, IL–2, IL–4, IL–6, IL–10, IL–12, IL17–α, IL–18, IFN–γ, TNF–α, G–CSF, and GM–CSF) were quantified through selective mouse ELISA methods. Myocadial fibrosis, necrosis and hypertrophy were analyzed through Immunohistochemistry (IHC). Human cardiomyocytes (HFC cell line) were exposed to subclinical concentration of doxorubicin (200 nM) alone or in combination to Singo ( at 10, 25 and 50 µg/ml) for 24 and 48h. Cell viability studies were performed through MTS assay. Expression of NLRP3 and p65/NF–kB) were made through selective ELISA methods. Results In preclinical models of short–term DOXO cardiotoxicity, Singo improved significantly EF and FS and prevented the reduction of radial and longitudinal strain after 10 days of treatment with DOXO. A reduced expression of myocardial NLRP3 and NF–kB levels in cardiac tissues were seen in DOXO–Singo group compared to DOXO mice (p<0.05). Myocardial expression of pro–inflammatory cytokines were significantly reduced after treatment with Singo indicating anti–inflammatory properties. Myocardial levels of Cal–granulin S100 and galectine–3 were strongly enhanced in DOXO group; on the other hand their expression were reduced in Singo–DOXO group vs DOXO (p<0.05). Immunohistochemistry analysis indicates that Singo reduces fibrosis and hypertrophy in myocardial tissue of mice during exposure to DOXO. Conclusion Singo is able to improve cardiac function and reduce biomarkers involved in heart failure and fibrosis. Cardioprotective properties of Singo are mediated by the reduction of lipid peroxidation products and expression of NLRP3–NF–kB –cytokine pathways.

Polysaccharide based supramolecular injectable hydrogels for in situ treatment of bladder cancer

Implantable system maximizes drug concentration and continuously releases drugs near the tumor, which is an effective tool to solve the difficult retention of chemotherapy drugs in bladder cancer. In this work, a novel polysaccharide supramolecular injectable hydrogel (CCA hydrogels for short) is rapidly constructed by simply mixing cationic chitosan, anionic sulfobutyl ether β-cyclodextrin (SBE-β-CD) and a trace amount of silver ions. The injected hydrogel reconstituted and regained its shape in less than 1 h, and it can still maintain the elasticity suitable for the human body. By packaging the drug directly, the gel achieves a high concentration of doxorubicin, an anticancer drug. Using MB49-luc cells as the model of bladder tumor for anti-tumor in vivo, the CCA-DOX gel has obvious inhibitory effect on bladder tumor, and its inhibitory effect is much greater than that of free DOX. Therefore, this self-healing injectable hydrogel has great potential for in situ treatment of bladder cancer.

Occupational Exposure during Intraperitoneal Pressurized Aerosol Chemotherapy Using Doxorubicin in a Pig Model

BackgroundThis study evaluated occupational exposure levels of doxorubicin in healthcare workers performing rotational intraperitoneal pressurized aerosol chemotherapy (PIPAC) procedures. MethodsAll samples were collected during PIPAC procedures applying doxorubicin to an experimental animal model (pigs). All procedures were applied to seven pigs, each for approximately 44 min. Surface samples (n = 51) were obtained from substances contaminating the PIPAC devices, surrounding objects, and protective equipment. Airborne samples were also collected around the operating table (n = 39). All samples were analyzed using ultra-high performance liquid chromatography-mass spectrometry. ResultsAmong the surface samples, doxorubicin was detected in only five samples (9.8%) that were directly exposed to antineoplastic drug aerosols in the abdominal cavity originating from PIPAC devices. The telescopes showed concentrations of 0.48–5.44 ng/cm2 and the trocar showed 0.98 ng/cm2 in the region where the spraying nozzles were inserted. The syringe line connector showed a maximum concentration of 181.07 ng/cm2, following a leakage. Contamination was not detected on the surgeons' gloves or shoes. Objects surrounding the operating table, including tables, operating lights, entrance doors, and trocar holders, were found to be uncontaminated. All air samples collected at locations where healthcare workers performed procedures were found to be uncontaminated. ConclusionsMost air and surface samples were uncontaminated or showed very low doxorubicin concentrations during PIPAC procedures. However, there remains a potential for leakage, in which case dermal exposure may occur. Safety protocols related to leakage accidents, selection of appropriate protective equipment, and the use of disposable devices are necessary to prevent occupational exposure.

Abstract 2527: Investigation of doxorubicin interference in flow cytometry measurements of apoptosis and necrosis

Abstract Background: Doxorubicin (DOX) is frequently used for investigations of breast cancer using flow cytometry with fluorescent stains for apoptosis and necrosis. DOX interference, however, can occur with these fluorescent measurements which is not reported in many published reports. The objectives of this study were to identify such interference and to assess its extent. Methods: MDA-MB-231 and MCF-7 cells were incubated for 24 h with 0.1, 1, and 10 µM DOX. Cells were then stained for apoptosis and necrosis using two commercial assay kits. Fluorescence was measured with FL1 (apoptosis), FL2 (primary for DOX), and FL3 (necrosis) detectors in cells with DOX alone, with DOX plus stains, and in control cells without DOX. Measurements were repeated two to five times using replicates and trials. Statistics were evaluated by t-tests. Results: Overall, DOX fluorescence interference increased with concentration in both cell lines. After DOX incubation, cells stained with caspase 3/7 and SYTOX showed fluorescence in the FL1 detector indicating caspase 3/7 activation in apoptosis. But the DOX component of fluorescence with this detector ranged from 11 to 95%. Dox fluorescence in the FL3 detector for SYTOX measurements indicating necrosis ranged from 26 to 96% of total fluorescence. Cells stained with Annexin V (with the FITC label) and propidium iodide (PI) showed fluorescence in the FL1 detector for Annexin V indicating apoptosis. However, the DOX component of fluorescence ranged from 11 to 25%. DOX fluorescence in the FL3 detector for PI indicating necrosis ranged from 87 to 106%. Conclusions: Without correction for DOX interference, and even at low concentrations, substantial errors can occur for apoptosis and necrosis measurements using flow cytometry with these stains in breast cancer cells. At high DOX concentrations, the interference can erroneously indicate an extensive presence of these cell death processes. Corrections for DOX interference include background subtraction and flow cytometer compensation. Acknowledgments: The authors gratefully acknowledge financial support from the Agnes Varis Trust for Women in Science (REN), the Milton Lev Memorial Faculty Research Fund (CMO) as well as Saint Joseph’s University support for student research. The authors also thank Bin Chen, PhD, and Richard Howley for assistance with flow cytometry. Citation Format: Rachel E. Nicoletto, Richard Wilkes, Clyde M. Ofner. Investigation of doxorubicin interference in flow cytometry measurements of apoptosis and necrosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2527.

Reduced Graphene Oxide and Gold Nanoparticles-Modified Electrochemical Aptasensor for Highly Sensitive Detection of Doxorubicin

Doxorubicin (DOX) is the most clinically important antibiotic in cancer treatment, but its severe cardiotoxicity and other side effects limit its clinical use. Therefore, monitoring DOX concentrations during therapy is essential to improve efficacy and reduce adverse effects. Here, we fabricated a sensitive electrochemical aptasensor for DOX detection. The sensor used gold wire as the working electrode and was modified with reduced graphene oxide (rGO)/gold nanoparticles (AuNPs) to improve the sensitivity. An aptamer was used as the recognition element for the DOX. The 5' end of the aptamer was modified with a thiol group, and thus immobilized to the AuNPs, and the 3' end was modified with methylene blue, which acts as the electron mediator. The combination between the aptamer and DOX would produce a binding-induced conformation, which changes the electron transfer rate, yielding a current change that correlates with the concentration of DOX. The aptasensor exhibited good linearity in the DOX concentration range of 0.3 μM to 6 μM, with a detection limit of 0.1 μM. In addition, the aptasensor was used for DOX detection in real samples and results, and showed good recovery. The proposed electrochemical aptasensor will provide a sensitive, fast, simple, and reliable new platform for detecting DOX.