A chitosan-camouflaged nanomedicine triggered by hierarchically stimuli to release drug for multimodal imaging-guided chemotherapy of breast cancer.

Breast cancer remains one of the most intractable diseases, especially the malignant form of metastasis, with which the cancer cells are hard to track and eliminate. Herein, the common known carbohydrate polymer chitosan (CS) was innovatively used as a shelter for the potent tumor-killing agent. The designed nanoparticles (NPs) not only enhance the solubility of hydrophobic paclitaxel (PTX), but also provide a "hide" effect for cytotoxic PTX in physiological condition. Moreover, coupled with the photothermal (PTT) properties of MoS2, results in a potent chemo/PTT platform. The MoS2@PTX-CS-K237 NPs have a uniform size (135 ± 17 nm), potent photothermal properties (η = 31.5 %), and environment-responsive (low pH, hypoxia) and near infrared (NIR) laser irradiation-triggered PTX release. Through a series of in vitro and in vivo experiments, the MoS2@PTX-CS-K237 showed high affinity and specificity for breast cancer cells, impressive tumor killing capacity, as well as the effective inhibitory effect of metastasis. Benefit from the unique optical properties of MoS2, this multifunctional nanomedicine also exhibited favorable thermal/PA/CT multimodality imaging effect on tumor-bearing mice. The system developed in this work represents the advanced design concept of hierarchical stimulus responsive drug release, and merits further investigation as a potential nanotheranostic platform for clinical translation.

Enhanced Therapeutic Potential of Hybrid Exosomes Loaded with Paclitaxel for Cancer Therapy.

The advancement of exosome studies has positioned engineered exosomes as crucial biomaterials for the development of advanced drug delivery systems. This study focuses on developing a hybrid exosome system by fusing mesenchymal stem cells (MSCs) exosomes with folate-targeted liposomes. The aim was to improve the drug loading capacity and target modification of exosome nanocarriers for delivering the first-line chemotherapy drug paclitaxel (PTX) and its effectiveness was assessed through cellular uptake studies to evaluate its ability to deliver drugs to tumor cells in vitro. Additionally, in vivo experiments were conducted using a CT26 tumor-bearing mouse model to assess the therapeutic efficacy of hybrid exosomes loaded with PTX (ELP). Cellular uptake studies demonstrated that ELP exhibited superior drug delivery capabilities to tumor cells in vitro. Moreover, in vivo experiments revealed that ELP significantly suppressed tumor growth in the CT26 tumor-bearing mouse model. Notably, for the first time, we examined the tumor microenvironment following intratumoral administration of ELP. We observed that ELP treatment activated CD4+ and CD8+ T cells, reduced the expression of M2 type tumor-associated macrophages (TAMs), polarized TAMs towards the M1 type, and decreased regulatory T cells (Tregs). Our research highlights the considerable therapeutic efficacy of ELP and its promising potential for future application in cancer therapy. The development of hybrid exosomes presents an innovative approach to enhance drug delivery and modulate the tumor microenvironment, offering exciting prospects for effective cancer treatment strategies.

Systematic profiling of Taxol resistance and sensitivity to tubulin missence mutations at molecular and cellular levels.

Taxol (paclitaxel) is the first approved microtubule-stabilizing agent (MSA) by binding stoichiometrically to tubulin, which is considered to be one of the most significant advances in first-line chemotherapy against diverse tumors. However, a large number of residue missence mutations harboring in the tubulin have been observed to cause acquired drug resistance, largely limiting the clinical application of Taxol and its analogs in chemotherapy. A systematic investigation of the intermolecular interactions between the Taxol and various tubulin mutants would help to establish a comprehensive picture of drug response to tubulin mutations in clinical treatment of cancer, and to design new MSA agents with high potency and selectivity to overcome drug resistance. In this study, we described an integration of in silico analysis and in vitro assay (iSiV) to profile Taxol against a panel of 149 clinically observed, cancer-associated missence mutations in ß-tubulin at molecular and cellular levels, aiming to a systematic understanding of molecular mechanism and biological implication underlying drug resistance and sensitivity conferring from tubulin mutations. It is revealed that the Taxol-resistant mutations can be classified into three types: (I) nonbonded interaction broken due to mutation, (II) steric hindrance caused by mutation, and (III) conformational change upon mutation. In addition, we identified three new Taxol-resistant mutations (C239Y, T274I, and R320P) that can largely reduce the binding affinity of Taxol to tubulin at molecular level, in which the T274I and R320P were observed to considerably impair the antitumor activity of Taxol at cellular level. Moreover, a novel drug-susceptible mutation (M363T) was also identified, which improves Taxol affinity by 2.6-fold and decreases Taxol antitumor EC50 values from 29.4 to 18.7 µM.

Examination of Wnt signaling as a therapeutic target for pancreatic ductal adenocarcinoma (PDAC) using a pancreatic tumor organoid library (PTOL).

Pancreatic ductal adenocarcinoma (PDAC) presents at advanced stages and is refractory to most treatment modalities. Wnt signaling activation plays a critical role in proliferation and chemotherapeutic resistance. Minimal media conditions, growth factor dependency, and Wnt dependency were determined via Wnt inhibition for seven patient derived organoids (PDOs) derived from pancreatic tumor organoid libraries (PTOL). Organoids demonstrating response in vitro were assessed in vivo using patient-derived xenografts. Wnt (in)dependent gene signatures were identified for each organoid. Panc269 demonstrated a trend of reduced organoid growth when treated with ETC-159 in combination with paclitaxel or gemcitabine as compared with chemotherapy or ETC-159 alone. Panc320 demonstrated a more pronounced anti-proliferative effect in the combination of ETC-159 and paclitaxel but not with gemcitabine. Panc269 and Panc320 were implanted into nude mice and treated with ETC-159, paclitaxel, and gemcitabine as single agents and in combination. The combination of ETC-159 and paclitaxel demonstrated an anti-tumor effect greater than ETC-159 alone. Extent of combinatory treatment effect were observed to a lesser extent in the Panc320 xenograft. Wnt (in)dependent gene signatures of Panc269 and 320 were consistent with the phenotypes displayed. Gene expression of several key Wnt genes assessed via RT-PCR demonstrated notable fold change following treatment in vivo. Each pancreatic organoid demonstrated varied niche factor dependencies, providing an avenue for targeted therapy, supported through growth analysis following combinatory treatment of Wnt inhibitor and standard chemotherapy in vitro. The clinical utilization of this combinatory treatment modality in pancreatic cancer PDOs has thus far been supported in our patient-derived xenograft models treated with Wnt inhibitor plus paclitaxel or gemcitabine. Gene expression analysis suggests there are key Wnt genes that contribute to the Wnt (in)dependent phenotypes of pancreatic tumors, providing plausible mechanistic explanation for Wnt (in)dependency and susceptibility or resistance to treatment on the genotypic level.

CCAAT enhancer binding protein delta activates vesicle associated membrane protein 3 transcription to enhance chemoresistance and extracellular PD-L1 expression in triple-negative breast cancer.

BACKGROUND: Chemoresistance and immunosuppression are two major obstacles in the current anti-cancer treatments. This study investigates the involvements of a CCAAT enhancer binding protein delta (CEBPD)/vesicle associated membrane protein 3 (VAMP3) axis in paclitaxel (PTX) resistance and immune evasion in triple-negative breast cancer (TNBC). METHODS: PTX resistance-related genes were screened by bioinformatics. CEBPD and VAMP3 expression in clinical TNBC samples was examined by immunohistochemistry. Three PTX-resistant TNBC cell lines (MDA-MB-231/PTX, MDA-MB-468/PTX and MDA-MB-453/PTX) were generated, and their drug resistance was analyzed. Autophagy of cells was analyzed by immunofluorescence staining. Interaction between CEBPD and VAMP3 promoter was identified by immunoprecipitation and luciferase assays. The extracellular expression of programmed cell death-ligand 1 (PD-L1) in TNBC cells was detected. Extracellular vesicles (EVs) from TNBC cells were isolated to examine their effects on CD8+ T cell exhaustion. RESULTS: CEBPD and VAMP3 were upregulated in chemo-resistant tissue samples and in PTX-resistant TNBC cells. The CEBPD downregulation enhanced PTX sensitivity of cells. However, further upregulation of VAMP3 in cells restored PTX resistance, which was likely due to the activation of autophagy, as the autophagy antagonist chloroquine enhanced PTX sensitivity of cells. CEBPD was found to bind to the VAMP3 promoter to activate its transcription. The CEBPD/VAMP3 axis also increased the PD-L1 expression in the conditioned medium of TNBC cells. The TNBC cell-derived EVs increased the exhaustion of co-cultured CD8+ T cells. CONCLUSION: This study provides novel evidence that CEBPD plays a key role in enhancing PTX resistance in TNBC cells across various subtypes through VAMP3-mediated autophagy activation. Additionally, the CEBPD/VAMP3 axis also increases extracellular PD-L1 level, delivered by cancer cell-derived EVs, to suppress CD8+ T cell-mediated anti-tumor immune response. These significant observations may provide new insights into the treatment of TNBC, suggesting CEBPD and VAMP3 as promising targets to overcome treatment resistance.

Novel Anti-tumor Strategy for Breast Cancer: Synergistic Role of Oleuropein with Paclitaxel Therapeutic in MCF-7 Cells.

BACKGROUND: The side effects of conventional therapeutics pose a problem for cancer treatment. Recently, combination treatments with natural compounds have attracted attention regarding limiting the side effects of treatment. Oleuropein is a natural polyphenol in olives that has antioxidant and anticancer effects. OBJECTIVES: This study aimed to investigate the oxidative stress effect of a combination of Paclitaxel, a chemotherapeutic agent, and Oleuropein in the MCF-7 cell line. METHODS: The xCELLigence RTCA method was used to determine the cytotoxic effects of Oleuropein and Paclitaxel in the MCF-7 cell line. The Total Oxidant and Total Antioxidant Status were analyzed using a kit. The Oxidative Stress Index was calculated by measuring Total Oxidant and Total Antioxidant states. The levels of superoxide dismutase, reduced glutathione and malondialdehyde, which are oxidative stress markers, were also measured by ELISA assay kit. RESULTS: As a result of the measurement, IC50 doses of Oleuropein and Paclitaxel were determined as 230 µM and 7.5 µM, respectively. Different percentages of combination ratios were generated from the obtained IC50 values. The effect of oxidative stress was investigated at the combination rates of 10%, 20%, 30%, and 40% which were determined to be synergistic. In terms of the combined use of Oleuropein and Paclitaxel on oxidative stress, antioxidant defense increased, and Oxidative Stress Index levels decreased. CONCLUSION: These findings demonstrate that the doses administered to the Oleuropein+Paclitaxel combination group were lower than those administered to groups using one agent alone (e.g. Paclitaxel), the results of which reduce the possibility of administering toxic doses.

Anti-cancer effects of alpha lipoic acid, cisplatin and paclitaxel combination in the OVCAR-3 ovarian adenocarcinoma cell line.

BACKGROUND: Ovarian cancer is the leading cause of gynecological cancer deaths. One of the major challenges in treating ovarian cancer with chemotherapy is managing the resistance developed by cancer cells to drugs, while also minimizing the side effects caused by these agents In the present study, we aimed to examine the effects of a combination of alpha lipoic acid (ALA), with cisplatin and paclitaxel in ovarian cancer(OVCAR-3). METHODS: The cytotoxic effects of ALA, cisplatin and paclitaxel on OVCAR-3 cells were determined. Four groups were formed: Control, ALA, Cisplatin + Paclitaxel, ALA + Cisplatin + Paclitaxel. The effects of single and combined therapy on cell migration, invasion and colony formation were analyzed. Changes in the expression of genes related to apoptosis, cell adhesion and cell cycle were analyzed with Real-time polymerase chain reaction(RT-PCR). The oxidative stress index and The Annexin V test were performed. RESULTS: The reduction in rapamycin-insensitive companion of mTOR(RICTOR) expression in the ALA + Cisplatin + Paclitaxel group was found statistically significant(p < 0.05). The decrease in MMP-9 and - 11 expressions the ALA + Cisplatin + Paclitaxel group was statistically significant(p < 0.05). The lowest values for mitogen-activated protein kinase(MAPK) proteins were found in the ALA + Cisplatin + Paclitaxel group. No colony formation was observed in the Cisplatin + Paclitaxel and ALA + Cisplatin + Paclitaxel groups. The lowest wound healing at 24 h was seen in the ALA + Cisplatin + Paclitaxel group. CONCLUSIONS: This study is the first one to investigate the combined treatment of ALA, Cisplatin, Paclitaxel on OVCAR-3. While ALA alone was not effective, combined therapy with ALA, has been found to reduce cell invasion, especially wound healing in the first 24 h, along with tumor cell adhesion.

Ginsenoside Rh2-Based Multifunctional Liposomes for Advanced Breast Cancer Therapy.

Background: Most solid tumors are not diagnosed and treated until the advanced stage, in which tumors have shaped mature self-protective power, leading to off-target drugs and nanomedicines. In the present studies, we established a more realistic large tumor model to test the antitumor activity of a multifunctional ginsenoside Rh2-based liposome system (Rh2-lipo) on advanced breast cancer. Methods: Both cholesterol and PEG were substituted by Rh2 to prepare the Rh2-lipo using ethanol-water system and characterized. The effects of Rh2-lipo on cell uptake, penetration of the tumor spheroid, cytotoxicity assay was investigated with 4T1 breast cancer cells and L929 fibroblast cells. The 4T1 orthotopic-bearing large tumor model was established to study the targeting effect of Rh2-lipo and inhibitory effect of paclitaxel loaded Rh2-lipo (PTX-Rh2-lipo) on advanced breast tumors. Results: Rh2-lipo exhibit many advantages that address the limitations of current liposome formulations against large tumors, such as enhanced uptake in TAFs and tumor cells, high targeting and penetration capacity, cytotoxicity against TAFs, normalization of the vessel network, and depletion of stromal collagen. In in vivo study, PTX-Rh2-lipo effectively inhibiting the growth of advanced breast tumors and outperformed most reported PTX formulations, including Lipusu® and Abraxane®. Conclusion: Rh2-lipo have improved drug delivery efficiency and antitumor efficacy in advanced breast cancer, which offers a novel promising platform for advanced tumor therapy.

Structure-based design and synthesis of BML284 derivatives: A novel class of colchicine-site noncovalent tubulin degradation agents.

Our previous studies have demonstrated that BML284 is a colchicine-site tubulin degradation agent. To improve its antiproliferative properties, 45 derivatives or analogs of BML284 were designed and synthesized based on the cocrystal structure of BML284 and tubulin. Among them, 5i was the most potent derivative, with IC50 values ranging from 0.02 to 0.05 µM against the five tested tumor cell lines. Structure-activity relationship studies verified that the N1 atom of the pyrimidine ring was the key functional group for its tubulin degradation ability. The 5i-tubulin cocrystal complex revealed that the binding pattern of 5i to tubulin is similar to that of BML284. However, replacing the benzodioxole ring with an indole ring strengthened the hydrogen bond formed by the 2-amino group with E198, which improved the antiproliferative activity of 5i. Compound 5i effectively suppressed tumor growth at an intravenous dose of 40 mg/kg (every 2 days) in paclitaxel sensitive A2780S and paclitaxel resistant A2780T ovarian xenograft models, with tumor growth inhibition values of 79.4% and 82.0%, respectively, without apparent side effects, showing its potential to overcome multidrug resistance. This study provided a successful example of crystal structure-guided discovery of 5i as a colchicine-targeted tubulin degradation agent, expanding the scope of targeted protein degradation.

Heterologous expression of taxane genes confers resistance to fall armyworm in Nicotiana benthamiana.

KEY MESSAGE: Taxadiene synthase, taxadiene-5α-hydroxylase, and taxane 13α-hydroxylase genes were introduced into Nicotiana benthamiana, and the improved resistance to lepidoptera pest fall armyworm was reported. Fall armyworm (FAW) is a serious agricultural pest. Genetic engineering techniques have been used to create pest-resistant plant varieties for reducing pest damage. Paclitaxel is a diterpenoid natural metabolite with antineoplastic effects in medicine. However, the effects of taxanes on the growth and development of lepidoptera pests, such as the FAW, are unknown. Here, selected paclitaxel precursor biosynthesis pathway genes, taxadiene synthase, taxane 5α-hydroxylase, and taxane 13α-hydroxylase, were engineered in the heterologous host Nicotiana benthamiana plants. Bioassay experiments showed that the transgenic N. benthamiana plants displayed improved resistance to FAW infestation, with degeneration of gut tissues and induced expression of apoptosis-related genes. Cytotoxicity experiment showed that the paclitaxel precursor, 10-deacetylbaccatin III, is cytotoxic to Sf9 cells, causing cell cycle arrest at the G2/M phase and disorder of the cytoskeleton. Metabolome analysis showed that heterologous expression of taxane genes in N. benthamiana affected the digestive system, steroid hormone and purine metabolism pathways of FAW larvae. In summary, this study provides a candidate approach for FAW control.

LINC00115 promotes chemoresistant breast cancer stem-like cell stemness and metastasis through SETDB1/PLK3/HIF1α signaling.

BACKGROUND: Cancer stem-like cell is a key barrier for therapeutic resistance and metastasis in various cancers, including breast cancer, yet the underlying mechanisms are still elusive. Through a genome-wide lncRNA expression profiling, we identified that LINC00115 is robustly upregulated in chemoresistant breast cancer stem-like cells (BCSCs). METHODS: LncRNA microarray assay was performed to document abundance changes of lncRNAs in paclitaxel (PTX)-resistant MDA-MB-231 BCSC (ALDH+) and non-BCSC (ALDH-). RNA pull-down and RNA immunoprecipitation (RIP) assays were performed to determine the binding proteins of LINC00115. The clinical significance of the LINC00115 pathway was examined in TNBC metastatic lymph node tissues. The biological function of LINC00115 was investigated through gain- and loss-of-function studies. The molecular mechanism was explored through RNA sequencing, mass spectrometry, and the CRISPR/Cas9-knockout system. The therapeutic potential of LINC00115 was examined through xenograft animal models. RESULTS: LINC00115 functions as a scaffold lncRNA to link SETDB1 and PLK3, leading to enhanced SETDB1 methylation of PLK3 at both K106 and K200 in drug-resistant BCSC. PLK3 methylation decreases PLK3 phosphorylation of HIF1α and thereby increases HIF1α stability. HIF1α, in turn, upregulates ALKBH5 to reduce m6A modification of LINC00115, resulting in attenuated degradation of YTHDF2-dependent m6A-modified RNA and enhanced LINC00115 stability. Thus, this positive feedback loop provokes BCSC phenotypes and enhances chemoresistance and metastasis in triple-negative breast cancer. SETDB1 inhibitor TTD-IN with LINC00115 ASO sensitizes PTX-resistant cell response to chemotherapy in a xenograft animal model. Correlative expression of LINC00115, methylation PLK3, SETDB1, and HIF1α are prognostic for clinical triple-negative breast cancers. CONCLUSIONS: Our findings uncover LINC00115 as a critical regulator of BCSC and highlight targeting LINC00115 and SETDB1 as a potential therapeutic strategy for chemotherapeutic resistant breast cancer.

Design of Novel 2-Phenylquinazolin-4-amines as Selective CYP1B1 Inhibitors for Overcoming Paclitaxel Resistance in A549 Cells.

Cytochrome P450 1B1 (CYP1B1) contributes to the metabolic inactivation of chemotherapeutics when overexpressed in tumor cells. Selective inhibition of CYP1B1 holds promise for reversing drug resistance. In our pursuit of potent CYP1B1 inhibitors, we designed and synthesized a series of 2-phenylquinazolin-4-amines. A substantial proportion of these newly developed inhibitors demonstrated inhibitory activity against CYP1B1, accompanied by improved water solubility. Remarkably, compound 14b exhibited exceptional inhibitory efficacy and selectivity toward CYP1B1. Molecular docking studies suggested that the expansion of the π-system through aromatization, the introduction of an amine group, and iodine atom augmented the binding affinity. Furthermore, inhibitors 14a, 14b, and 14e demonstrated the ability to significantly reduce the resistance in A549 cells to paclitaxel, while also inhibiting the migration and invasion of these cells. Finally, radioiodine labeling experiments shed light on the metabolic pathway of compound 5l in mice, highlighting the potential of 125I-5l as a radioactive probe for future research endeavors.

PEGylated mesoporous silica core-shell redox-responsive nanoparticles for delivering paclitaxel to breast cancer cells.

Controlling the drug release and restricting its presence in healthy organs is extremely valuable. In this study, mesoporous silica nanoparticles (MSN) as the core, loaded with paclitaxel (PTX), were coated with a non-porous silica shell functionalized with disulfide bonds. The nanoparticles were further coated with polyethylene glycol (PEG) via disulfide linkages. We analyzed the physicochemical properties of nanoparticles, including hydrodynamic size via Dynamic Light Scattering (DLS), zeta potential, X-ray Diffraction (XRD) patterns, Fourier-Transform Infrared (FTIR) spectra, and imaging through Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). The drug release profile in two distinct glutathione (GSH) concentrations of 2 µM and 10 µM was measured. The cellular uptake of nanoparticles by MCF-7 cell line was determined using Confocal Laser Scanning Microscopy (CLSM) images and flow cytometry. Furthermore, the cell viability and the capability of nanoparticles to induce apoptosis in MCF-7 cell line were studied using the MTT assay and flow cytometry, respectively. Our investigations revealed that the release of PTX from the drug delivery system was redox-responsive. Also, results indicated an elevated level of cellular uptake and efficient induction of apoptosis, underscoring the promising potential of this redox-responsive drug delivery system for breast cancer therapy.

Co-Delivery Polymeric Poly(Lactic-Co-Glycolic Acid) (PLGA) Nanoparticles to Target Cancer Stem-Like Cells.

Nanoparticle drug delivery has been promoted as an effective mode of delivering antineoplastic therapeutics. However, most nanoparticle designs fail to consider the multifaceted tumor microenvironment (TME) that produce pro-tumoral niches, which are often resistant to chemo- and targeted therapies. In order to target the chemoresistant cancer stem-like cells (CSCs) and their supportive TME, in this chapter we describe a nanoparticle-based targeted co-delivery that addresses the paracrine interactions between CSC and non-cancerous mesenchymal stem cells (MSCs) in the TME. Carcinoma-activated MSCs have been shown to increase the chemoresistance and metastasis of CSC. Yet their contributions to protect the CSC TME have not yet been systematically investigated in the design of nanoparticles for drug delivery. Therefore, we describe the fabrication of degradable poly(lactic-co-glycolic acid) (PLGA) nanoparticles (120-200 nm), generated with an electrospraying process that encapsulates both a conventional chemotherapeutic, paclitaxel, and a targeted tyrosine kinase inhibitor, sunitinib, to limit MSC interactions with CSC. In the 3D hetero-spheroid model that comprises both CSCs and MSCs, the delivery of sunitinib as a free drug disrupted the MSC-protected CSC stemness and migration. Therefore, this chapter describes the co-delivery of paclitaxel and sunitinib via PLGA nanoparticles as a potential targeted therapy strategy for targeting CSCs. Overall, nanoparticles can provide an effective delivery platform for targeting CSCs and their TME together. Forthcoming studies can corroborate similar combined therapies with nanoparticles to improve the killing of CSC and chemoresistant cancer cells, thereby improving treatment efficiency.

Harnessing the potential of de-sulfated heparin for targeted drug delivery: A three-component approach exemplified by conjugation with galactose and paclitaxel.

Heparin, an anticoagulant with a century-long history of use, has been investigated over the past decade as a potential drug delivery vehicle. Despite its safety and efficacy, its interactions with many proteins through specific sulfate patterns can complicate drug delivery by mediating diverse biological functions. Here, we present the synthesis of a three-component drug delivery system comprising de-sulfated heparin as the carrier, galactose as the targeting moiety, and paclitaxel as the therapeutic drug. Removal of sulfates eliminated most of its anticoagulant effects in all intermediates. Through coupling with galactose and paclitaxel, the system improved the solubility of the drug and achieved selective targeting and efficient drug delivery to HepG2 cells, a liver carcinoma cell line with high galactose receptor expression. While the three-component system exhibited a slightly higher IC50 value than native paclitaxel, demonstrating its efficacy as a drug carrier, the IC50 value for the normal human liver cell line QSG7701 was significantly higher, indicating its selectivity and safety. Our study introduces a novel approach utilizing desulfated heparin as a carrier, warranting further investigation to unlock its potential in targeted drug delivery strategies.

Long-Acting Heterodimeric Paclitaxel-Idebenone Prodrug-Based Nanomedicine Promotes Functional Recovery after Spinal Cord Injury.

After spinal cord injury (SCI), successive systemic administration of microtubule-stabilizing agents has been shown to promote axon regeneration. However, this approach is limited by poor drug bioavailability, especially given the rapid restoration of the blood-spinal cord barrier. There is a pressing need for long-acting formulations of microtubule-stabilizing agents in treating SCI. Here, we conjugated the antioxidant idebenone with microtubule-stabilizing paclitaxel to create a heterodimeric paclitaxel-idebenone prodrug via an acid-activatable, self-immolative ketal linker and then fabricated it into chondroitin sulfate proteoglycan-binding nanomedicine, enabling drug retention within the spinal cord for at least 2 weeks and notable enhancement in hindlimb motor function and axon regeneration after a single intraspinal administration. Additional investigations uncovered that idebenone can suppress the activation of microglia and neuronal ferroptosis, thereby amplifying the therapeutic effect of paclitaxel. This prodrug-based nanomedicine simultaneously accomplishes neuroprotection and axon regeneration, offering a promising therapeutic strategy for SCI.

A novel fluorescent probe for visualizing viscosity changes in lipid droplets during chemotherapy-induced ferroptosis.

BACKGROUND: Ferroptosis, as a novel form of cell death, is becoming one of the hot topics in cancer treatment research. It differs from necrosis and autophagy in that it involves the accumulation of lipid peroxides and is triggered by iron dependency. Recent studies have suggested that this mechanism may alter the viscosity or structure of lipid droplets (LDs). The relationship between LDs viscosity and ferroptosis remains an active area of research with limited reports at present. Additionally, there is a lack of effective anticancer drugs targeting the ferroptosis pathway to promote ferroptosis in tumour cells. Therefore, the development of tools to detect viscosity changes during ferroptosis and targeted therapeutic strategies is of great significance. RESULTS: By coupling 1,3-indandione with naphthalimide, including decamethylamine as a LDs recognition group, we designed and synthesized an environmental fluorescent probe that induces intramolecular charge transfer (TICT) effects. Notably, the diffusion and transport of intracellular substances may be affected in highly viscous environments. Under such conditions, intracellular iron ions may accumulate, leading to peroxide production and cellular damage, which can trigger ferroptosis. Therefore, WD-1 achieved excellent in situ bioimaging of LDs targeting and its viscosity during ferroptosis in HeLa cells and zebrafish. Furthermore, it was observed that WD-1 effectively differentiated between malignant and normal cells during this process, highlighting its potential significance in distinguishing cellular states. In addition, we used the antitumour drug paclitaxel to study ferroptosis in cancer cells. These findings not only provide an excellent tool for the development of the ferroptosis response, but also are crucial for understanding the biological properties of LDs during the ferroptosis response. SIGNIFICANCE AND NOVELTY: Based on a powerful tool of fluorescent probe with in vivo bioimaging, we developed WD-1 to track the impact of paclitaxel on the process of ferroptosis in living cells. Therefore, we preliminarily believe that paclitaxel may affect the occurrence of ferroptosis and control apoptosis in cancer cells. These findings not only serve as an exceptional tool for advancing our understanding of the ferroptosis response, but furthermore play a vital role in comprehending the biological characteristics of LDs in relation to ferroptosis.

Biological differences of three paclitaxel- and sirolimus-coated balloons on coronary lesions in a rabbit model.

BACKGROUND: Drug-coated balloons (DCBs) are important treatment options for coronary artery disease; however, randomised controlled trials comparing various DCB technologies are sparse, and further investigations are needed. AIMS: This preclinical study aimed to histologically and biologically compare the drug effects and safety of a low-dose paclitaxel-coated DCB (PCB; AGENT), a regular-dose PCB (SeQuent Please NEO) and a sirolimus-coated DCB (SCB; MagicTouch). METHODS: The DCBs were inflated in the healthy iliac arteries of 18 rabbits, which were euthanised after 28 days. The treated iliac arteries and distal skeletal muscles were histopathologically evaluated, and drug concentrations were measured. RESULTS: In the histopathological evaluation, the medial smooth muscle cell loss score regarding depth, an indicator of drug efficacy, was significantly higher with AGENT and SeQuent Please NEO than with MagicTouch (4.0 [3.6-4.0] vs 3.7 [3.7-4.0] vs 2.2 [2.0-2.4]), with significant differences in comparisons between AGENT and MagicTouch (p<0.01) and between SeQuent Please NEO and MagicTouch (p<0.01). AGENT and SeQuent Please NEO showed comparable drug concentrations in the treated artery (p=0.61). In contrast, the drug concentrations in distal skeletal muscles were the highest for MagicTouch, followed by SeQuent Please NEO and AGENT (28.07 [13.19-52.46] ng/mg vs 0.66 [0.22-3.76] ng/mg vs 0.25 [0.04-3.23] ng/mg, respectively). CONCLUSIONS: This study demonstrated that PCBs might have higher efficacy and lower drug concentrations in distal skeletal muscles than the MagicTouch SCB. The efficacy of the AGENT low-dose PCB and the SeQuent Please NEO regular-dose PCB was comparable.

Characterisation of new in vitro models and identification of potentially active drugs in angiosarcoma.

Angiosarcoma is a rare soft tissue sarcoma originating from endothelial cells. Given that current treatments for advanced disease have shown limited efficacy, alternative therapies need to be identified. In rare diseases, patient-derived cell models are crucial for screening anti-tumour activity. In this study, cell line models were characterised in 2D and 3D cultures. The cell lines' growth, migration and invasion capabilities were explored, confirming them as useful tools for preclinical angiosarcoma studies. By screening a drug library, we identified potentially effective compounds: 8-amino adenosine impacted cell growth and inhibited migration and invasion at considerably low concentrations as a single agent. No synergistic effect was detected when combining with paclitaxel, gemcitabine or doxorubicin. These results suggest that this compound could be a potentially useful drug in the treatment of AGS.

Computational and in vitro analyses on synergistic effects of paclitaxel and thymoquinone in suppressing invasive breast cancer cells.

BACKGROUND: In the present experiment, we evaluated the impact of thymoquinone (TQ) and paclitaxel (PTX) treatment on MDA-MB-231 cell line growth inhibition via controlling apoptosis/autophagy. MATERIALS AND RESULTS: MDA-MB-231cells were exposed to PTX (0, 25, 50, 75, and 100 nM), TQ (0, 25, 50, 75, and 100 µM), and combinations for 48 h. After the MTT assessment, dose-response curves and IC50 values were calculated, and the combination synergism was evaluated using the Compusyn software. Following the treatment with PTX, TQ, and combinations at IC50 doses, the expression of apoptosis and autophagy genes was assessed in cells. The GraphPad Prism program was used to analyze the data, and Tukey's test at p < 0.05 was then run. PTX, TQ, and their combinations inhibited MDA-MB-231cell proliferation and viability dose-dependently. TQ reduced the effective concentration (IC50) of PTX in co-treatment groups. PTX and TQ showed antagonistic effects when cell proliferation declined above 70%. Antagonistic effects shifted into additive and synergistic effects upon increasing PTX concentration, indicated by diminished cell proliferation below 70%. PTX-TQ co-treatment significantly enhanced P53 and BAX expression while reducing Bcl-2 expression. Also, their combination increased Beclin-1, ATG-5, and ATG-7 expression in treated cells. CONCLUSION: Effective concentrations of TQ and PTX had synergic effects and inhibited breast cancer cells via prompting apoptosis and autophagy in vitro.