Enhanced Drug Uptake Research Articles

Microbubble Enhanced Delivery of Vitamin C for Treatment of Colorectal Cancer.

During chemotherapy treatment for cancer, often only a fraction of the administered dose reaches the tumor site, with the remaining drug spreading throughout the body, producing unwanted side-effects and restricting how much drug can be safely administered. A potential solution to reduce this problem is the use of microbubbles. The interaction between microbubbles and ultrasound generates pores in the tumor cells, permitting enhanced drug uptake. This study investigates the delivery of the ascorbic acid derivative, palmitoyl ascorbate, to KRAS-mutated colorectal cancer cells in vitro. Ultrasound-triggered microbubbles enhanced the efficacy of liposomal palmitoyl ascorbate treatments by 1.7- and 2.2-fold in LS174T and HCT116 CRC cell lines, respectively. This enhancement was achieved without increasing the drug dosage, and the therapeutic effect was shown to be localized to the area that received the ultrasound pulse, aiding in the reduction of off-site toxicity.

Therapeutic Effects of Puerarin Loaded Bone Marrow Mesenchymal Stem Cell-Derived Exosomes in a Rat Model of Osteoarthritis.

Osteoarthritis (OA) is the most prevalent chronic degenerative joint disease among the aged population. The primary objective of this study was to assess the therapeutic potential of puerarin loaded bone marrow mesenchymal stem cell-derived exosomes (Pue@BMSC-Exo), and reveal their inflammatory regulating mechanisms through affecting the nuclear factor kappa-B (NF-κB) signaling pathway. In this study, exosomes derived from BMSCs were isolated and identified. Cell proliferation and migration were evaluated by CCK-8 and scratch methods. Furthermore, histological and micro-computed tomography analysis were performed to assess alterations of articular cartilage in OA rats. Results showed that BMSC-Exo and Pue@BMSC-Exo conformed with the basic characteristics of exosomes. BMSC-Exo increased the solubility of Pue and enhanced drug uptake by chondrocytes. In addition, Pue@BMSC-Exo stimulated proliferation and migration of chondrocyte, and also promoted cartilage repair by reducing matrix metalloproteinase MMP13 production and increasing type II collagen (Col2) synthesis. Furthermore, Pue@BMSC-Exo, by effectively inhibiting the NF-κB signaling pathway, reduced the production of inflammatory mediators and attenuated the release of the inflammatory marker nitric oxide (NO), ultimately ameliorating the damage of chondrocyte. These findings exhibited the potential therapeutic significance of Pue@BMSC-Exo in OA and warranted further exploration in clinical applications.

Solute Dispersion in Casson Blood Flow through a Stenosed Artery with the Effect of Temperature and Electric Field

This study develops a mathematical model to address solute dispersion in arterial blood flow, particularly considering the effects of temperature and electric fields using the Casson fluid model. Given the physiological importance of drug delivery within the human vascular system, understanding these dynamics is crucial, especially in the presence of cardiovascular diseases (CVD). The Generalized Dispersion Model (GDM) is employed to simulate the dispersion function. Results demonstrate that elevated temperatures and electric fields enhance drug uptake and distribution by increasing blood flow. The model accurately predicts drug behavior in narrowed arteries, optimizing dosage regimens and improving therapeutic outcomes. Visual representations and detailed discussions of these findings are presented in the subsequent sections. The results are validated against a previous study that did not consider the effects of stenosis height, temperature and electric field. The findings suggest a strong agreement between the two studies. Additionally, an increase in mean absorption leads to an increase in velocity. When mean absorption increases, the functions of steady dispersion and overall dispersion decrease, while the function of unsteady dispersion increases. The reverse behavior is observed for the electric field. The study concludes that integrating temperature and electric field effects into drug delivery systems can significantly enhance treatment efficacy and reduce side effects, providing a valuable tool for advanced targeted therapies in CVD and cancer management.

Recent Advancements of Hyaluronic Acid Nanoscaffolds in Arthritis Management

AbstractArthritis is a significant health concern affecting over 528 million people globally, reducing quality of life. The chronic nature of arthritis, coupled with insufficient therapeutic effectiveness, recurrence, and adverse side effects, complicates its management. Hyaluronic acid (HA) has emerged as a promising solution due to its biocompatibility, non‐toxicity, and targeted drug delivery capabilities, being a key component of the cartilage extracellular matrix widely used in managing arthritis. HA's inherent viscoelastic property and ability to target CD44 have spurred interest in developing HA‐based systems for delivering drugs to manage arthritis. Hyaluronic acid nanoscaffolds (HA‐NSCfs) show improved outcomes over treatments, including enhanced drug uptake through receptor‐mediated targeting, prolonged retention in the synovium, reduced proinflammatory mediator expression, enhanced cartilage regeneration, reduced drug toxicity due to sustained release, and more cost‐effective treatments. This review highlights the rationale for using HA‐NSCfs for the management and advanced drug delivery systems in arthritis, emphasizing preclinical and clinical results. It discusses various solid‐lipid nanoparticles, hydroxyapatite nanoparticles, polyelectrolyte complexes, liposomes, bilosomes, drug‐polymer conjugates, hydrogels, inorganic nanoparticles, and polymer nanoparticles, etc reported for arthritis management. Additionally, the review identifies key challenges and offers suggestions to address them, ultimately highlighting the potential of HA‐NSCfs as a topical treatment for arthritis.

Functional exosomes modified with chitosan effectively alleviate anthracycline-induced cardiotoxicity

Anthracyclines belong to a class of anti-tumor antibiotics, and their severe cardiotoxicity significantly limits their clinical use. Exosomes play key roles in intercellular communication, characterized by high biocompatibility and specific tissue and organ homing effects. In this study, doxorubicin, an anthracycline anticancer drug widely used in clinical chemotherapy, was selected as a model drug. To address the significant cardiotoxicity associated with doxorubicin, tumor exosomes are utilized as drug carriers. The homing effect of autologous exosomes enhances drug uptake by tumor cells and reduces cardiotoxicity. To enhance the stability of exosomes, improve therapeutic effectiveness, and reduce toxic side effects, chitosan was utilized to modify the surface of exosomes. Chitosan has a specific anti-tumor effect because it can target the CD44 receptor of tumor stem cells and interact with tumor cells through charge adsorption. Through in vitro cell experiments, in vivo pharmacokinetic experiments, and an in situ ectopic nude mouse tumor model, the study demonstrated that chitosan-modified tumor exosomes significantly alleviated the severe cardiotoxicity of doxorubicin, while also showing remarkable anti-tumor efficacy. This study introduces a novel approach to reduce the adverse side effects of anthracycline chemotherapeutic drugs and presents a highly promising nanocarrier delivery system.

Enhanced Cellular Doxorubicin Uptake via Delayed Exposure Following Nanosecond Pulsed Electric Field Treatment: An In Vitro Study.

The combination of nanosecond Pulsed Electric Field (nsPEF) with pharmaceuticals is a pioneering therapeutic method capable of enhancing drug uptake efficacy in cells. Utilizing nsPEFs configured at 400 pulses, an electric field strength of 15 kV/cm, a pulse duration of 100 ns, and a repetition rate of 10 pulses per second (PPS), we combined the nsPEF with a low dose of doxorubicin (DOX) at 0.5 μM. Upon verifying that cells could continuously internalize DOX from the surrounding medium within 1 h post nsPEF exposure, we set the DOX exposure period to 10 min and contrasted the outcomes of varying sequences of DOX and nsPEF administration: pulsing followed by DOX, DOX followed by pulsing, and DOX applied 40 min after pulsing. Flow cytometry, CCK-8 assays, and transmission electron microscopy (TEM) were employed to examine intracellular DOX accumulation, cell viability, apoptosis, cell cycle, and ultrastructural transformations. Our findings demonstrate that exposing cells to DOX 40 min subsequent to nsPEF treatment can effectively elevate intracellular DOX levels, decrease cell viability, and inhibit the cell cycle. This research work presents a novel approach to enhance DOX uptake efficiency with moderate conditions of both DOX and nsPEF.

Improving chemoradiotherapy strategy with PEGylated doxorubicin loaded gold nanoparticles against oral cancers

Chemoradiotherapy, a combination treatment paradigm in oncology, where chemotherapy and radiation therapy are administered concurrently. Nanomedicine based Drug delivery at tumour site and radiosensitizer can minimize the adverse effects of chemoradiation. In this study, one pot and facile method was used to synthesize two nanotherapeutics Doxorubicin reduced gold nanoparticles (Au Dox NPs) and Doxorubicin complexed in PEGylated gold nanoparticles (Au Dox PEG NPs). Both were physico-chemically characterized by spectroscopy methods to confirm formation of gold nanoparticles and conjugation of Dox. Advanced electron microscopy was used to analyze morphology and nano architect of the nanotherapeutics. Drug release kinetics was analyzed by dialysis method. KB cells were X-ray irradiated by LINAC facility at 4 Gy dose. Cytotoxicity, radiation and chemoradiation damage was measured by MTT assay. Stability assay to measure the agglomeration and stability in biological medium. The resultant two nanotherapeutics synthesized, Au Dox NPs and Au Dox PEG NPs are stable nanoformulations successfully loaded with Dox. Both had average size of ∼20 nm and negative surface charge and near spherical morphology. Conjugated Dox molecule is conserved. KB cancer cell line in vitro cellular studies revealed that the Au Dox NPs had enhanced drug uptake and superior cytotoxicity and radiosensitization in comparison to Au Dox PEG NPs and free Dox, thereby providing a synergistic approach for treatment of oral cancer. In the current study promising results obtained at preclinical in vitro model, the potential of Au Dox PEG NPs for drug delivery system can be enhanced by tagging with antibodies/small molecules for targeted treatment of oral cancers, also further investigation in vivo model warranted.

The Increased Dissolution and Oral Absorption of Itraconazole by Nanocrystals with an Endogenous Small-Molecule Surfactant as a Stabilizer.

The aim of this study was to develop cholic-acid-stabilized itraconazole nanosuspensions (ITZ-Nanos) with the objective of enhancing drug dissolution and oral absorption. A laboratory-scale microprecipitation-high-pressure homogenization method was employed for the preparation of the ITZ-Nanos, while dynamic light scattering, transmission electron microscope analysis, X-ray diffraction, differential scanning calorimetry, and high-performance liquid chromatography analysis were utilized to evaluate their physicochemical properties. The absorption and bioavailability of the ITZ-Nanos were assessed using Caco-2 cells and rats, with Sporanox® pellets as a comparison. Prior to lyophilization, the particle size of the ITZ-Nanos measured approximately 225.7 nm. Both X-ray diffraction and differential scanning calorimetry confirmed that the ITZ remained crystalline within the nanocrystals. Compared to the pellets, the ITZ-Nanos exhibited significantly higher levels of supersaturation dissolution and demonstrated enhanced drug uptake by the Caco-2 cells. The AUC(0-t) value for the ITZ-Nanos in rats was 1.33-fold higher than that observed for the pellets. These findings suggest that cholic acid holds promise as a stabilizer for ITZ nanocrystals, as well as potentially other nanocrystals.

Paraptotic Cell Death as an Unprecedented Mode of Action Observed for New Bipyridine-Silver(I) Compounds Bearing Phosphane Coligands.

In this work, we investigated the anticancer activity of several novel silver(I) 2,2'-bipyridine complexes containing either triphenylphosphane (PPh3) or 1,2-bis(diphenylphosphino)ethane (dppe) ligands. All compounds were characterized by diverse analytical methods including ESI-MS spectrometry; NMR, UV-vis, and FTIR spectroscopies; and elemental analysis. Moreover, several compounds were also studied by X-ray single-crystal diffraction. Subsequently, the compounds were investigated for their anticancer activity against drug-resistant and -sensitive cancer cells. Noteworthily, neither carboplatin and oxaliplatin resistance nor p53 deletion impacted on their anticancer efficacy. MES-OV cells displayed exceptional hypersensitivity to the dppe-containing drugs. This effect was not based on thioredoxin reductase inhibition, enhanced drug uptake, or apoptosis induction. In contrast, dppe silver drugs induced paraptosis, a novel recently described form of programmed cell death. Together with the good tumor specificity of this compound's class, this work suggests that dppe-containing silver complexes could be interesting drug candidates for the treatment of resistant ovarian cancer.

Lipid Horizons: Recent Advances and Future Prospects in LBDDS for Oral Administration of Antihypertensive Agents.

The lipid-based drug delivery system (LBDDS) is a well-established technique that is anticipated to bring about comprehensive transformations in the pharmaceutical field, impacting the management and administration of drugs, as well as treatment and diagnosis. Various LBDDSs verified to be an efficacious mechanism for monitoring hypertension systems are SEDDS (self-nano emulsifying drug delivery), nanoemulsion, microemulsions, vesicular systems (transferosomes and liposomes), and solid lipid nanoparticles. LBDDSs overcome the shortcomings that are associated with antihypertensive agents because around fifty percent of the antihypertensive agents experience a few drawbacks including short half-life because of hepatic first-pass metabolism, poor aqueous solubility, low permeation rate, and undesirable side effects. This review emphasizes antihypertensive agents that were encapsulated into the lipid carrier to improve their poor oral bioavailability. Incorporating cutting-edge technologies such as nanotechnology and targeted drug delivery, LBDDS holds promise in addressing the multifactorial nature of hypertension. By fine-tuning drug release profiles and enhancing drug uptake at specific sites, LBDDS can potentially target renin-angiotensin-aldosterone system components, sympathetic nervous system pathways, and endothelial dysfunction, all of which play crucial roles in hypertension pathophysiology. The future of hypertension management using LBDDS is promising, with ongoing reviews focusing on precision medicine approaches, improved biocompatibility, and reduced toxicity. As we delve deeper into understanding the intricate mechanisms underlying hypertension, LBDDS offers a pathway to develop next-generation antihypertensive therapies that are safer, more effective, and tailored to individual patient needs.

Calreticulin P-domain-derived “Eat-me” peptides for enhancing liposomal uptake in dendritic cells

Discovering new ligands for enhanced drug uptake and delivery has been the core interest of the drug delivery field. This study capitalizes on the natural “eat-me” signal of calreticulin (CRT), proposing a novel strategy for functionalizing liposomes to improve cellular uptake. CRT is presented on the surfaces of apoptotic cells, and it plays a crucial role in immunogenic cell death (ICD). This is because it is essential for antigen uptake via low-density lipoprotein (LDL) receptor-mediated phagocytosis. Inspired by this mechanism, we interrogated CRT’s “eat-me” feature using CRT-derived peptides to functionalize liposomes. We studied liposomal formulation stability, properties, cellular uptake, toxicity, and intracellular trafficking in dendritic cells. We identified key peptide fragments of CRT, specifically from the hydrophilic P-domain, that are compatible with liposomal formulations. Contrary to the more hydrophobic N-domain peptides, the P-domain peptides induced significantly higher liposomal uptake in DC2.4 dendritic cells than cationic DOTAP and anionic DPPG liposomes without inducing toxicity. The P-domain-derived peptides led to enhanced liposomal uptake into DC2.4 dendritic cells compared to the standard DPPC liposomes. The uptake can be partially blocked by the receptor-associated protein (RAP). Upon internalization, P-domain-peptide-decorated liposomes showed higher co-localization with lysosomes compared to the standard DPPC liposomes. Our findings illuminate CRT's operational role and identify P-domain peptides as promising agents for developing biomimetic drug delivery systems that can potentially replicate CRT's “eat-me” function.

Dual Responsive Magnetic Drug Delivery Nanomicelles with Tumor Targeting for Enhanced Cancer Chemo/Magnetothermal Synergistic Therapy.

Stimulus-responsive nanocarrier systems are promising in cancer treatment. They improve drug stability and facilitate controlled drug release. However, single-responsive nanocarriers still face insufficient tumor targeting and low efficacy. In this study, we synthesized folate-modified DSPE-PEOz nanomicelles with PEG chains and loaded them with magnetic iron particles and doxorubicin (DOX). Folic acid (FA) was employed as a ligand to target cancer cells actively. The nanomicelles are biocompatible and acid-sensitive drug carriers. Magnetic field-responsive nanoparticles enable moderately controlled magnetothermal therapy of tumors regardless of tumor location. The pH/magnetic field dual-responsive nanomicelles shed their PEG layer in response to tumor tissue acidity and react to magnetic fields through magnetothermal effects. In vitro and in vivo experiments demonstrated that the nanomicelles could efficiently target cancer cells, release drugs in response to pH changes, and enhance drug uptake through magnetothermal effects. The dual-responsive magnetic nanomicelles are expected to enhance the anti-cancer efficacy of chemo/magnetothermal synergistic therapy.

Macropinocytosis As a Means of Selectively Targeting RAS-Mutant Multiple Myeloma

Introduction Roughly, 50% of multiple myeloma (MM) is driven by mutant RAS, both at presentation and more at relapse. Currently, in MM there are no clinical approaches to target this disease subset and ongoing strategies to inhibit RAS function or downstream effectors have had limited clinical success in other tumors. This has prompted our team to look into other more indirect modes of RAS-selective targeting. Oncogenic RAS-driven cancers use a unique actin-driven endocytosis pathway, termed macropinocytosis (MP), to increase the nutrient supply and sustain proliferation. To create a strategy for targeting RAS mutant MM, we have investigated whether RAS-mutant MM cells undergo MP and whether this process can be exploited as a therapeutic vulnerability, by utilizing this pro-oncogenic biochemical mechanism to selectively deliver a toxin to the MM clone using a MP selective monobody-drug conjugate (MDC). Methods The MDC relies on a proprietary fibronectin-based scaffold (monobody) identified based on its physiochemical properties that facilitates MP selective internalization, and therefore targets RAS-mutant MM tumor cells, with a very favorable pharmacokinetic profile. MMAE was attached to the monobody with a cathepsin-cleavable linker and a maleimide group for conjugation to the C-terminal free cysteine on the monobody protein (MDC-MMAE). MDC-MMAE was pre-clinically evaluated both in-vitro and in-vivo, in human MM cell lines, patient cells and a doxycycline inducible mutant KRAS cell system. Results In-vitro cell line and patient cell studies demonstrated that RAS-mutant MM cells undergo MP whereas wild type (WT) cells do not. To understand the role of mutant RAS in driving uptake of the MDC, a doxycycline-inducible mutant KRAS V12 KMS11 system was established. The functionality of the inducibility of the cell system was verified using protein expression and membrane ruffling in the presence of doxycycline. Fluorescently-labeled monobody (MDC-Cy5.5) and TMR-Dextran underwent a high level of uptake in the presence of induced mutant RAS. In contrast, in conditions where MP was absent, no uptake of MDC-Cy5.5 and TMR-Dextran was seen. Furthermore, when KMS11 KRASV12 and WT KMS11 were treated with MDC-MMAE, a 2-fold increase in cell death was observed in the mutant RAS cell line compared to wild type RAS. In-vivo studies showed that the pharmacological properties of the drug when conjugated to the monobody enabled faster serum clearance compared to antibody drug conjugates (ADCs) and nanomaterials, while maintaining cellular impermeability allowing enhanced drug uptake via MP. Importantly, in-vivo the MDC-MMAE technology had an improved toxicity profile compared to ADC-MMAE, increasing tolerable drug delivery by upwards of 15-fold. To test the anti-tumor effects in-vivo, the L363 (NRAS Q61), WT KMS11, and KMS11 KRASV12 cell lines were subcutaneously injected into MM murine models. After tumors were established, 0.5mg/kg MDC-MMAE was administered every 7 days. Mutant RAS L363 and KMS11 KRASV12 tumors treated with MDC-MMAE exhibited roughly a 6-fold decrease in tumor size after 21 days while WT KMS11 tumors showed no significant difference in tumor volume. MDC-MMAE at 5mg/kg showed complete tumor regression as a single agent in L363 tumors. Improved outcomes were seen with MDC-MMAE in combination with standard of care options at lower doses. Additionally, MDC-MMAE has displayed enhanced immunogenic cell death that has not been seen with other chemotherapeutic options, making it an ideal partner for immunotherapy combination. Conclusion Limited clinical options exist for the treatment of mutant RAS MM tumors. We show that by taking advantage of MP, a process upregulated in RAS-mutant cancers, MDC-MMAE specifically targets and inhibits MM growth and improves survival in murine models. It can also be combined with other MM standard of care drugs and with immunotherapy drugs to have a potentially important clinical effect. In collaboration with Tezcat Biosciences, the MDC-MMAE technology has achieved a phase II SBIR for advancement to clinical application.

A novel convex acoustic lens-attached ultrasound drug delivery system and its testing in a murine melanoma subcutaneous model

Target-specific drug release is indispensable to improve chemotherapeutic efficacy as it enhances drug uptake and penetration into tumors. Sono-responsive drug-loaded nano-/micro-particles are a promising solution for achieving target specificity by exposing them to ultrasound near tumors. However, the complicated synthetic processes and limited ultrasound (US) exposure conditions, such as limited control of ultrasound focal depth and acoustic power, prevent the practical application of this approach in clinical practice. Here, we propose a convex acoustic lens-attached US (CALUS) as a simple, economic, and efficient alternative of focused US for drug delivery system (DDS) application. The CALUS was characterized both numerically and experimentally using a hydrophone. In vitro, microbubbles (MBs) inside microfluidic channels were destroyed using the CALUS with various acoustic parameters (acoustic pressure [P], pulse repetition frequency [PRF], and duty cycle) and flow velocity. In vivo, tumor inhibition was evaluated using melanoma-bearing mice by characterizing tumor growth rate, animal weight, and intratumoral drug concentration with/without CALUS DDS. US beams were measured to be efficiently converged by CALUS, which was consistent with our simulation results. The acoustic parameters were optimized through the CALUS-induced MB destruction test (P = 2.34 MPa, PRF = 100 kHz, and duty cycle = 9%); this optimal parameter combination successfully induced MB destruction inside the microfluidic channel with an average flow velocity of up to 9.6 cm/s. The CALUS also enhanced the therapeutic effects of an antitumor drug (doxorubicin) in vivo in a murine melanoma model. The combination of the doxorubicin and the CALUS inhibited tumor growth by ∼ 55% more than doxorubicin alone, clearly indicating synergistic antitumor efficacy. Our tumor growth inhibition performance was better than other methods based on drug carriers, even without a time-consuming and complicated chemical synthesis process. This result suggests that our novel, simple, economic, and efficient target-specific DDS may offer a transition from preclinical research to clinical trials and a potential treatment approach for patient-centered healthcare.

The role of peptides in reversing chemoresistance of breast cancer: current facts and future prospects.

Breast cancer is the first malignant tumor in women, and its incidence is also increasing year by year. Chemotherapy is one of the standard therapies for breast cancer, but the resistance of breast cancer cells to chemotherapy drugs is a huge challenge for the effective treatment of breast cancer. At present, in the study of reversing the drug resistance of solid tumors such as breast cancer, peptides have the advantages of high selectivity, high tissue penetration, and good biocompatibility. Some of the peptides that have been studied can overcome the resistance of tumor cells to chemotherapeutic drugs in the experiment, and effectively control the growth and metastasis of breast cancer cells. Here, we describe the mechanism of different peptides in reversing breast cancer resistance, including promoting cancer cell apoptosis; promoting non-apoptotic regulatory cell death of cancer cells; inhibiting the DNA repair mechanism of cancer cells; improving the tumor microenvironment; inhibiting drug efflux mechanism; and enhancing drug uptake. This review focuses on the different mechanisms of peptides in reversing breast cancer drug resistance, and these peptides are also expected to create clinical breakthroughs in promoting the therapeutic effect of chemotherapy drugs in breast cancer patients and improving the survival rate of patients.

Abstract 4905: Anticancer activity and paraptosis induction of novel bipyridine-silver(I) compounds against resistant colorectal and ovarian cancer cell lines

Abstract Background: Platinum-based anticancer drugs (e.g. Carboplatin and Oxaliplatin) are frequently applied in chemotherapy regimens against several types of cancer including ovarian carcinoma (OC) and colorectal carcinoma (CRC). However, intrinsic or acquired tumor resistance severely limit their clinical application. Here, we investigated the anticancer activity of several novel silver(I) 2,2’-bipyridine derivatives, containing either triphenylphosphane (PPh3) or 1,2-bis(diphenylphosphino)ethane (dppe) ligands and tested their potential to overcome platinum resistance. Methods: Cytotoxicity and cross resistance profiles of the newly synthesized compounds were tested against two OC models (SKOV-3 and MES-OV), a CRC model (HCT-116) and their corresponding sublines resistant to carboplatin or oxaliplatin, as well as non-malignant fibroblasts (F331) via an MTT-based cell viability assay after 72 h continuous drug exposure. Moreover, the intracellular levels of silver were measured via ICP-MS. In addition, thioredoxin reductase (TrxR) inhibition properties, impact on cell cycle distribution and apoptosis induction potential were investigated via multiple molecular biological methods. Morphological changes induced by the silver compounds were characterized via spinning disk confocal microscopy. Results: All tested compounds displayed pronounced anticancer activity and cancer cell selectivity. Moreover, cell intrinsic resistance to carboplatin or oxaliplatin was not impacting on the cytotoxic activity of the compounds. Noteworthy, MES-OV and HCT-116 cells showed exceptional sensitivity to several silver(I) 2,2’-bipyridine derivatives with a 1,2-bis(diphenylphosphino)ethane (dppe) (AP-compounds). This sensitivity was not based on enhanced drug uptake, pronounced TrxR inhibition nor apoptosis induction or cell cycle arrest. In contrast, hypersensitive cells displayed pronounced endoplasmic reticulum (ER)-derived vesicles together with multiple others hallmarks of paraptotic cell death. Conclusion: Our findings did not only demonstrate that the new silver compounds were unaffected by cancer cell intrinsic resistance mechanisms to platinum-based chemotherapy, but also indicated a high vulnerability of tumor (sub)types towards these bipyridine silver complexes. This hypersensitivity is based on the induction of paraptosis, a novel form of programmed cell death. To summarize, these silver compounds represent a new class of promising anticancer drugs, which demand further preclinical development. Citation Format: Alessia Stefanelli, Ricardo G. Teixeira, Adhan Pilon, Rebecca Warmers, Ingo Ott, Christian R. Kowol, Anamaria Brozovic, Ana Isabel Tomaz, Andreia Valente, Petra Heffeter. Anticancer activity and paraptosis induction of novel bipyridine-silver(I) compounds against resistant colorectal and ovarian cancer cell lines. [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 4905.

Enhanced Drug Uptake on Application of Electroporation in a Single-Cell Model.

Electroporation method is a useful tool for delivering drugs into various diseased tissues in the human body. As a result of an applied electric field, drug particles enter the intracellular compartment through the temporarily permeabilized cell membrane. Consequently, electroporation method allows better penetration of the drug into the diseased tissue and improves treatment clinically. In this study, a more generalized model of drug transport in a single cell is proposed. The model is able to capture non-homogeneous drug transport in the cell due to non-uniform cell membrane permeabilization. Several numerical experiments are conducted to understand the effects of electric field and drug permeability on drug uptake into the cell. Through investigation, the appropriate electric field and drug permeability are identified, which lead to sufficient drug uptake into the cell. This model can be used by experimentalists to get information prior to conduct any experiment, and it may help reduce the number of actual experiments that might be conducted otherwise.

Peptide-induced mycobacterial membrane permeabilization studies to enhance drug uptake.

Anti-tubercular therapy is a long-term process during which the chances of drug resistance are high due to its inaccurate distribution. The bioavailability of the drug is limited due to the pharmacokinetic parameters and cell membrane barriers. Rational designing of the drug is essential to validate the required entry into the target cell to eliminate chances of resistance. Australian frog peptides aurein1.2 and maculatin1.1 have membrane-active properties which could be exploited to enhance the drug uptake in Mycobacterium. This work used a combination of biophysical techniques to study the peptide interaction patterns on mycobacterial cell envelope layers. Atomic force microscopy and surface plasmon resonance studies revealed that aurein1.2 insertion leads to lipid removal in the mycobacterial inner membrane lipids. In contrast, maculatin1.1 insertion leads to the blebbing of the bilayer. Dye-leakage assay performed using confocal microscopy promises aurein1.2 to effectively permeabilize outer and inner mycobacterial membranes, while maculatin1.1 permeabilizes selectively. However, flow cytometry studies indicated greater permeabilization of propidium iodide into the intact Mycobacterium smegmatis when treated with maculatin1.1, indicating the formation of a larger surface area of blebbing compared to the area of lipid removal by aurein1.2. When used in combination with anti-tubercular drugs smaller than the pores formed by the peptides, these molecules can spur up the drug uptake to enhance intracellular drug concentrations. Leveraging the membrane-drug interaction profiles unique to mycobacteria, specific chemotypes consisting of outer membrane-disruptive agents and anti-tubercular drugs may provide strategies for new combinational TB therapies.

Thermal-Responsive MXene-DNA Hydrogel for Near-Infrared Light Triggered Localized Photothermal-Chemo Synergistic Cancer Therapy.

Stimuli-responsive DNA hydrogels are promising candidates for cancer treatment, as they not only possess biocompatible and biodegradable 3D network structures as highly efficient carriers for therapeutic agents but also are capable of undergoing programmable gel-to-solution transition upon external stimuli to achieve controlled delivery. Herein, a promising platform for highly efficient photothermal-chemo synergistic cancer therapy is established by integrating DNA hydrogels with Ti3 C2 TX -based MXene as a photothermal agent and doxorubicin (DOX) as a loaded chemotherapeutic agent. Upon the irradiation of near-infrared light (NIR), temperature rise caused by photothermal MXene nanosheets triggers the reversible gel-to-solution transition of the DOX-loaded MXene-DNA hydrogel, during which the DNA duplex crosslinking structures unwind to release therapeutic agents for efficient localized cancer therapy. Removal of the NIR irradiation results in the re-formation of DNA duplex structures and the hydrogel matrix, and the recombination of free DOX and adaptive hydrogel transformations can also be achieved. As demonstrated by both in vitro and in vivo models, the MXene-DNA hydrogel system, with excellent biocompatibility and injectability, dynamically NIR-triggered drug delivery, and enhanced drug uptake under mild hyperthermia conditions, exhibits efficient localized cancer treatment with fewer side effects to the organisms.

Abstract 5329: Pt(IV)-M13, a blood-brain-barrier penetrant macrocyclic peptide-platinum(IV) conjugate, leads to enhanced drug uptake and efficacy in murine glioblastoma models

Abstract INTRODUCTION. Glioblastoma is the most aggressive primary malignant brain tumor and has a median survival of approximately 15 months. Treatment is hindered by the blood-brain barrier (BBB) that restricts entry of the vast majority of cancer therapeutics to the brain. We have designed a peptide-drug conjugate, (Pt(IV)-M13), comprised of M13, a perfluoroaryl-stapled cell-penetrating peptide, covalently linked to Pt(IV) via an amide bond. Upon intracellular reduction the Pt(IV) prodrug releases active cisplatin eliciting DNA damage and cell death. To investigate the properties of Pt(IV)-M13 in detail, we determined in vitro cell killing, platinum brain accumulation, biodistribution, and efficacy in mouse models. METHODS. Pt(IV)-M13 tumor cytotoxicity was assessed in vitro using standard approaches. In vivo platinum levels were measured in the brain by ICP-MS, and BBB penetration assessed through a multicellular 3D in vitro BBB model, and biodistribution to peripheral organs was determined. Toxicity from bi-weekly injections of the Pt(IV)-M13 platinum conjugate was monitored from 5mg/kg to 30mg/kg. Animal survival was determined in a glioblastoma xenograft model. DNA damage was quantified by γH2AX staining. RESULTS. Pt(IV)-M13 possesses in vitro tumor cell killing effects similar to cisplatin and Pt(IV) alone. Pt(IV)-M13 showed increased BBB penetration when compared to cisplatin in our in vitro BBB spheroid model (>20-fold), in brain tissue (7-fold) and glioblastoma tumor-bearing mice (8-fold). Five hours after intravenous injection, biodistribution of platinum delivered by Pt(IV)-M13 was higher than cisplatin in the spleen, but lower in the heart. Bi-weekly injections of Pt(IV)-M13 were well-tolerated in nude mice to at least 15mg/kg, three times the reported cisplatin MTD. Finally, Pt(IV)-M13 treatment increased survival in a murine glioblastoma xenograft model (median survival= 33 days for Pt(IV)-M13 vs. 22.5 days for cisplatin and 24 days Pt(IV) alone. Elevated γH2AX foci were observed in Pt(IV)-M13 treated mice providing direct support for the improved delivery of cisplatin to brain tumors using this approach. CONCLUSION. Pt(IV)-M13 leads to enhanced BBB penetration and cisplatin accumulation in glioblastoma models, with consequent animal survival benefit. Overall, our data support further investigation and development of Pt(IV)-M13 for glioblastoma treatment. Future studies will include additional glioblastoma models, and further optimization of this approach. Citation Format: Jorge-Luis Jimenez-Macias, Yen-Chun Lee, Tomer Finkelberg, Gilles Berger, Michal Nowicki, Choi-Fong Cho, Bogdan Fedeles, Andrei Loas, Brad Penetelute, Sean E. Lawler. Pt(IV)-M13, a blood-brain-barrier penetrant macrocyclic peptide-platinum(IV) conjugate, leads to enhanced drug uptake and efficacy in murine glioblastoma models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5329.