Polylactide-tethered prodrugs in polymeric nanoparticles as reliable nanomedicines for the efficient eradication of patient-derived hepatocellular carcinoma

Synergistic Nanomedicine Delivering Topoisomerase I Toxin (SN-38) and Inhibitors of Polynucleotide Kinase 3'-Phosphatase (PNKP) for Enhanced Treatment of Colorectal Cancer

Inhibitors of a DNA repair enzyme known as polynucleotide kinase 3'-phosphatase (PNKP) are expected to show synergistic cytotoxicity in combination with topoisomerase I (TOP1) inhibitors in cancer. In this study, the synergistic cytotoxicity of a novel inhibitor of PNKP, i.e., A83B4C63, with a potent TOP1 inhibitor, i.e., SN-38, against colorectal cancer cells was investigated. Polymeric micelles (PMs) for preferred tumor delivery of A83B4C63, developed through physical encapsulation of this compound in methoxy poly(ethylene oxide)-poly(α-benzyl carboxylate-ε-caprolactone) (mPEO-b-PBCL) micelles, were combined with SN-38 in free or PM form. The PM form of SN-38 was prepared through chemical conjugation of SN-38 to the functional end group of mPEO-b-PBCL and further assembly of mPEO-b-PBCL-SN-38 in water. Moreover, mixed micelles composed of mPEO-b-PBCL and mPEO-b-PBCL-SN-38 were used to co-load A83B4C63 and SN-38 in the same nanoformulation. The loading content (% w/w) of the SN-38 and A83B4C63 to mPEO-b-PBCL in the co-loaded formulation was 7.91 ± 0.66 and 16.13 ± 0.11% (w/w), respectively, compared to 15.67 ± 0.34 (% w/w) and 23.06 ± 0.63 (% w/w) for mPEO-b-PBCL micelles loading individual drugs. Notably, the average diameter of PMs co-encapsulating both SN-38 and A83B4C63 was larger than that of PMs encapsulating either of these compounds alone but still lower than 60 nm. The release of A83B4C63 from PMs co-encapsulating both drugs was 76.36 ± 1.41% within 24 h, which was significantly higher than that of A83B4C63-encapsulated micelles (42.70 ± 0.72%). In contrast, the release of SN-38 from PMs co-encapsulating both drugs was 44.15 ± 2.61% at 24 h, which was significantly lower than that of SN-38-conjugated PMs (74.16 ± 3.65%). Cytotoxicity evaluations by the MTS assay as analyzed by the Combenefit software suggested a clear synergy between PM/A83B4C63 (at a concentration range of 10-40 μM) and free SN-38 (at a concentration range of 0.001-1 μM). The synergistic cytotoxic concentration range for SN-38 was narrowed down to 0.1-1 or 0.01-1 μM when combined with PM/A83B4C63 at 10 or 20-40 μM, respectively. In general, PMs co-encapsulating A83B4C63 and SN-38 at drug concentrations within the synergistic range (10 μM for A83B4C63 and 0.05-1 μM for SN-38) showed slightly less enhancement of SN-38 anticancer activity than a combination of individual micelles, i.e., A83B4C63 PMs + SN-38 PMs at the same molar concentrations. This was attributed to the slower release of SN-38 from the SN-38 and A83B4C63 co-encapsulated PMs compared to PMs only encapsulating SN-38. Cotreatment of cells with TOP1 inhibitors and A83B4C63 formulation enhanced the expression level of γ-HA2X, cleaved PARP, caspase-3, and caspase-7 in most cases. This trend was more consistent and notable for PMs co-encapsulating both A83B4C63 and SN-38. The overall result from the study shows a synergy between PMs of SN-38 and A83B4C63 as a mixture of two PMs for individual drugs or PMs co-encapsulating both drugs.

Enhancing drug penetration in solid tumors via nanomedicine: Evaluation models, strategies and perspectives

Effective tumor treatment depends on optimizing drug penetration and accumulation in tumor tissue while minimizing systemic toxicity. Nanomedicine has emerged as a key solution that addresses the rapid clearance of free drugs, but achieving deep drug penetration into solid tumors remains elusive. This review discusses various strategies to enhance drug penetration, including manipulation of the tumor microenvironment, exploitation of both external and internal stimuli, pioneering nanocarrier surface engineering, and development of innovative tactics for active tumor penetration. One outstanding strategy is organelle-affinitive transfer, which exploits the unique properties of specific tumor cell organelles and heralds a potentially transformative approach to active transcellular transfer for deep tumor penetration. Rigorous models are essential to evaluate the efficacy of these strategies. The patient-derived xenograft (PDX) model is gaining traction as a bridge between laboratory discovery and clinical application. However, the journey from bench to bedside for nanomedicines is fraught with challenges. Future efforts should prioritize deepening our understanding of nanoparticle-tumor interactions, re-evaluating the EPR effect, and exploring novel nanoparticle transport mechanisms.

Liposomal Enzyme Nanoreactors Based on Nanoconfinement for Efficient Antitumor Therapy

Enzymatic reactions can consume endogenous nutrients of tumors and produce cytotoxic species and are therefore promising tools for treating malignant tumors. Inspired by nature where enzymes are compartmentalized in membranes to achieve high reaction efficiency and separate biological processes with the environment, we develop liposomal nanoreactors that can perform enzymatic cascade reactions in the aqueous nanoconfinement of liposomes. The nanoreactors effectively inhibited tumor growth in vivo by consuming tumor nutrients (glucose and oxygen) and producing highly cytotoxic hydroxyl radicals (⋅OH). Co-compartmentalization of glucose oxidase (GOx) and horseradish peroxidase (HRP) in liposomes could increase local concentration of the intermediate product hydrogen peroxide (H2 O2 ) as well as the acidity due to the generation of gluconic acid by GOx. Both H2 O2 and acidity accelerate the second-step reaction by HRP, hence improving the overall efficiency of the cascade reaction. The biomimetic compartmentalization of enzymatic tandem reactions in biocompatible liposomes provides a promising direction for developing catalytic nanomedicines in antitumor therapy.

Application of molecular dynamics simulation in self-assembled cancer nanomedicine

Self-assembled nanomedicine holds great potential in cancer theragnostic. The structures and dynamics of nanomedicine can be affected by a variety of non-covalent interactions, so it is essential to ensure the self-assembly process at atomic level. Molecular dynamics (MD) simulation is a key technology to link microcosm and macroscale. Along with the rapid development of computational power and simulation methods, scientists could simulate the specific process of intermolecular interactions. Thus, some experimental observations could be explained at microscopic level and the nanomedicine synthesis process would have traces to follow. This review not only outlines the concept, basic principle, and the parameter setting of MD simulation, but also highlights the recent progress in MD simulation for self-assembled cancer nanomedicine. In addition, the physicochemical parameters of self-assembly structure and interaction between various assembled molecules under MD simulation are also discussed. Therefore, this review will help advanced and novice researchers to quickly zoom in on fundamental information and gather some thought-provoking ideas to advance this subfield of self-assembled cancer nanomedicine.

Establishment and Characterization of Patient-Derived Xenograft Model of Non-Small-Cell Lung Cancer Derived from Malignant Pleural Effusions

Purpose

Non-small-cell lung cancer (NSCLC) comprises approximately 80% of all lung malignancies. The 5-year survival rate of patients with advanced lung cancer who lost their chances of surgery is approximately 15%. Suitable animal models are important in screening individualized treatment plans for patients with lung cancer, evaluating the pre-clinical efficacy of new drugs, and conducting basic research.

Patients and Methods

In this study, we collected malignant pleural effusion (MPE) samples from 31 patients with NSCLC, successfully constructed 11 NSCLC patient-derived xenografts (PDXs), and analyzed the factors affecting their successful establishment. Primary PDX tumors were characterized using histological analysis, immunohistochemistry, short tandem repeat (STR) profiling, and cytogenetic analysis.

Results

The PDXs preserved the histopathology and protein expression pattern of parental tumors. STR analysis revealed the PDX tissue and a tumor tissue of the same individual origin. Statistical analysis showed that the survival time of patients reflected the malignant degree of MPEs to a certain extent, thus affecting the establishment of PDXs. However, the age, gender, and clinical and biochemical indicators of the patients did not affect the establishment of PDX models.

Conclusion

These data suggest that the established NSCLC PDXs preserved the molecular characteristics of primary lung cancer and can serve as a new tool to elucidate the pathogenesis of tumors, explore new treatment methods, and conduct the research and development of new drugs for tumors.

Cyclometalated Ru(II)-NHC complexes with phenanthroline ligands induce apoptosis mediated by mitochondria and endoplasmic reticulum stress in cancer cells

The exploration of ruthenium complexes as anticancer drugs has been the focus of intense investigation. In this study, we synthesized and characterized four C,N-cyclometalated ruthenium(II) complexes (Ru1-Ru4) coordinated with pyridine-functionalized N-heterocyclic carbene (NHC) and auxiliary ligands (e.g., acetonitrile, 1,10-phenanthroline, 3,4,7,8-tetramethyl-1,10-phenanthroline, and 4,7-diphenyl-1,10-phenanthroline). X-ray diffraction analysis showed that all of the four cycloruthenated complexes are hexa-coordinated in a typical octahedral geometry. In vitro cytotoxic studies revealed that cyclometalated Ru-NHC complexes Ru3 and Ru4 had stronger anticancer activity than their corresponding Ru-NHC precursor Ru1 and the clinically used cisplatin. For HeLa cells, Ru3 and Ru4 exhibited potent cytotoxicity with the IC₅₀ value of 4.31 ± 0.42 μM and 3.14 ± 0.23 μM, respectively, which was approximately three times lower than that of cisplatin. More interestingly, Ru3 and Ru4 not only effectively inhibited the proliferation of HeLa cells, but also exhibited potential anti-migration activity. In the scratch wound healing assay, Ru3 and Ru4 treatment significantly reduced the wound healing rate of HUVEC cells. Mechanistic studies showed that Ru3 and Ru4 caused a dual action mode of mitochondrial membrane depolarization and endoplasmic reticulum stress and finally induced apoptosis of HeLa cells.

Patient-derived xenograft model in colorectal cancer basic and translational research

Colorectal cancer (CRC) is one of the most popular malignancies globally, with 930 000 deaths in 2020. The evaluation of CRC-related pathogenesis and the discovery of potential therapeutic targets will be meaningful and helpful for improving CRC treatment. With huge efforts made in past decades, the systematic treatment regimens have been applied to improve the prognosis of CRC patients. However, the sensitivity of CRC to chemotherapy and targeted therapy is different from person to person, which is an important cause of treatment failure. The emergence of patient-derived xenograft (PDX) models shows great potential to alleviate the straits. PDX models possess similar genetic and pathological characteristics as the features of primary tumors. Moreover, PDX has the ability to mimic the tumor microenvironment of the original tumor. Thus, the PDX model is an important tool to screen precise drugs for individualized treatment, seek predictive biomarkers for prognosis supervision, and evaluate the unknown mechanism in basic research. This paper reviews the recent advances in constructed methods and applications of the CRC PDX model, aiming to provide new knowledge for CRC basic research and therapeutics.

Taxanes prodrug-based nanomedicines for cancer therapy

Malignant tumor remains a huge threat to human health and chemotherapy still occupies an important place in clinical tumor treatment. As a kind of potent antimitotic agent, taxanes act as the first-line broad-spectrum cancer drug in clinical use. However, disadvantages such as prominent hydrophobicity, severe off-target toxicity or multidrug resistance lead to unsatisfactory therapeutic effects, which restricts its wider usage. The efficient delivery of taxanes is still quite a challenge despite the rapid developments in biomaterials and nanotechnology. Great progress has been made in prodrug-based nanomedicines (PNS) for cancer therapy due to their outstanding advantages such as high drug loading efficiency, low carrier induced immunogenicity, tumor stimuli-responsive drug release, combinational therapy and so on. Based on the numerous developments in this filed, this review summarized latest updates of taxanes prodrugs-based nanomedicines (TPNS), focusing on polymer-drug conjugate-based nanoformulations, small molecular prodrug-based self-assembled nanoparticles and prodrug-encapsulated nanosystems. In addition, the new trends of tumor stimuli-responsive TPNS were also discussed. Moreover, the future challenges of TPNS for clinical translation were highlighted. We here expect this review will inspire researchers to explore more practical taxanes prodrug-based nano-delivery systems for clinical use.

Bone tumors effective therapy through functionalized hydrogels: current developments and future expectations

Primary bone tumors especially, sarcomas affect adolescents the most because it originates from osteoblasts cells responsible for bone growth. Chemotherapy, surgery, and radiation therapy are the most often used clinical treatments. Regrettably, surgical resection frequently fails to entirely eradicate the tumor, which is the primary cause of metastasis and postoperative recurrence, leading to a high death rate. Additionally, bone tumors frequently penetrate significant regions of bone, rendering them incapable of self-repair, and impairing patients' quality of life. As a result, treating bone tumors and regenerating bone in the clinic is difficult. In recent decades, numerous sorts of alternative therapy approaches have been investigated due to a lack of approved treatments. Among the novel therapeutic approaches, hydrogel-based anticancer therapy has cleared the way for the development of new targeted techniques for treating bone cancer and bone regeneration. They include strategies such as co-delivery of several drug payloads, enhancing their biodistribution and transport capabilities, normalizing accumulation, and optimizing drug release profiles to decrease the limitations of current therapy. This review discusses current advances in functionalized hydrogels to develop a new technique for treating bone tumors by reducing postoperative tumor recurrence and promoting tissue repair.

Hypoxia-Responsive Stereocomplex Polymeric Micelles with Improved Drug Loading Inhibit Breast Cancer Metastasis in an Orthotopic Murine Model

Tumor metastasis is a leading cause of breast cancer-related death. Taxane-loaded polymeric formulations, such as Genexol PM and Nanoxel M using poly(ethylene glycol)-poly(d,l-lactide) (PEG-PLA) micelles as drug carriers, have been approved for the treatment of metastatic breast cancer. Unfortunately, the physical instability of PEG-PLA micelles, leading to poor drug loading, premature drug leakage, and consequently limited drug delivery to tumors, largely hinders their therapeutic outcome. Inspired by the enantiomeric nature of PLA, this work developed stereocomplex PEG-PLA micelles through stereoselective interactions of enantiomeric PLA, which are further incorporated with a hypoxia-responsive moiety used as a hypoxia-cleavable linker of PEG and PLA, to maximize therapeutic outcomes. The results showed that the obtained micelles had high structural stability, showing improved drug loading for effective drug delivery to tumors as well as other tissues. Especially, they were capable of sensitively responding to the hypoxic tumor environment for drug release, reversing hypoxia-induced drug resistance and hypoxia-promoted cell migration for enhanced bioavailability under hypoxia. In vivo results further showed that the micelles, especially at a high dose, inhibited the growth of the primary tumor and improved tumor pathological conditions, consequently remarkably inhibiting its metastasis to the lungs and liver, while not causing any systemic toxicity. Hypoxia-responsive stereocomplex micelles thus emerge as a reliable drug delivery system to treat breast cancer metastasis.

Combinatorial therapeutic strategies for enhanced delivery of therapeutics to brain cancer cells through nanocarriers: current trends and future perspectives

Brain cancer is the most aggressive one among various cancers. It has a drastic impact on people's lives because of the failure in treatment efficacy of the currently employed strategies. Various strategies used to relieve pain in brain cancer patients and to prolong survival time include radiotherapy, chemotherapy, and surgery. Nevertheless, several inevitable limitations are accompanied by such treatments due to unsatisfactory curative effects. Generally, the treatment of cancers is very challenging due to many reasons including drugs’ intrinsic factors and physiological barriers. Blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier (BCSFB) are the two additional hurdles in the way of therapeutic agents to brain tumors delivery. Combinatorial and targeted therapies specifically in cancer show a very promising role where nanocarriers’ based formulations are designed primarily to achieve tumor-specific drug release. A dual-targeting strategy is a versatile way of chemotherapeutics delivery to brain tumors that gets the aid of combined ligands and mediators that cross the BBB and reaches the target site efficiently. In contrast to single targeting where one receptor or mediator is targeted, the dual-targeting strategy is expected to produce a multiple-fold increase in therapeutic efficacy for cancer therapy, especially in brain tumors. In a nutshell, a dual-targeting strategy for brain tumors enhances the delivery efficiency of chemotherapeutic agents via penetration across the blood-brain barrier and enhances the targeting of tumor cells. This review article highlights the ongoing status of the brain tumor therapy enhanced by nanoparticle based delivery with the aid of dual-targeting strategies. The future perspectives in this regard have also been highlighted.

Poly(l-lactide-co-caprolactone-co-glycolide)-Based Nanoparticles as Delivery Platform: Effect of the Surfactants on Characteristics and Delivery Efficiency

Polymeric nanoparticles made of the copolymer Poly(L-lactide-co-caprolactone-co-glycolide) were prepared using the solvent evaporation method. Two different surfactants, polyvinyl alcohol and dextran, and a mixture of the two were employed. The three types of nanoparticles were used as hosting carriers of two chemotherapeutic drugs, the hydrophilic doxorubicin and the hydrophobic SN-38. The morphostructural characterization showed similar features for the three types of nanoparticles, while the drug encapsulation efficiency indicated that the dextran-based systems are the most effective with both drugs. Cellular studies with breast cancer cells were performed to compare the delivery capability and the cytotoxicity profile of the three nanosystems. The results show that the unloaded nanoparticles are highly biocompatible at the administered concentrations and confirmed that dextran-coated nanoparticles are the most efficient vectors to release the two drugs, exerting cytotoxic activity. PVA, on the other hand, shows limited drug release in vitro, probably due to strong interactions with both drugs. Data also show the release is more efficient for doxorubicin than for SN-38; indeed, the doxorubicin IC₅₀ value for the dextran-coated nanoparticles was about 35% lower than the free drug. This indicates that these nanocarriers are suitable candidates to deliver hydrophilic drugs while needing further modification to host hydrophobic molecules.

An esterase-activatable prodrug formulated liposome strategy: potentiating the anticancer therapeutic efficacy and drug safety

Liposomal nanomedicine represents a common and versatile carrier for the delivery of both lipophilic and hydrophilic drugs. However, the direct formulation of many chemotherapeutics into a liposomal system remains an enormous challenge. Using the topoisomerase I inhibitor 7-ethyl-10-hydroxycamptothecin (SN38) as a model drug, we combined lipophilic prodrug construction with subsequent integration into an exogenous liposomal scaffold to assemble a prodrug-formulated liposome for systemic administration. Reconstructing SN38 with lipid cholesterol via the esterase-activatable bond endows the resulting prodrug with elevated miscibility with liposomal compositions and esterase-responsive drug release in cancerous cells. The systemic administration of the prodrug-based nanoassemblies (Chol-SN38@LP) exhibited preferential accumulation of therapeutic payloads in tumor lesions. Compared to the SN38 clinical counterpart irinotecan, our prodrug-based nanoassemblies with adaptive features showed elevated therapeutic efficacy (∼1.5 times increase of tumor inhibition) in a preclinical A549 lung carcinoma cell-derived mouse model and improved drug tolerability (i.e., alleviated bloody diarrhea and liver damage) in multiple mice models. These results may be ascribed to extended systemic circulation and preferential tumor accumulation of our nanodrugs. Hence, our findings demonstrate that rational engineering of therapeutic nanomedicine is a promising approach for effective and safe delivery of antitumor chemotherapeutics, especially to rescue drug candidates that have failed in clinical trials owing to poor PK properties or severe toxicity in patients.

Active targeted Janus nanoparticles enable anti-angiogenic drug combining chemotherapy agent to prevent postoperative hepatocellular carcinoma recurrence

Surgery is one of the main effective strategies for the treatment of solid tumors, but high postoperative recurrence is also the main cause of death in current cancer therapy. The prevention of postoperative hepatocellular carcinoma (HCC) recurrence is a clinical problem that needs to be solved urgently. At present, there are still some problems to be solved, such as, how to achieve free drugs to target the site of surgical resection; develop a strategy for the simultaneous administration of multiple drugs to inhibit postoperative recurrence; and provide the appropriate animal model that mimics the process of postoperative HCC recurrence. In this study, we used a facile and reproducible method to successfully prepare amphiphilic Janus nanoparticles (JNPs). In order to improve targeting of the JNPs to residual HCC cells after surgery, we modified the side of gold nanorods (GNRs) with lactobionic acid (LA), thus creating LA-JNPs. This provided an active and targeted co-delivery system for hydrophilic and hydrophobic drugs in separate rooms, thus avoiding mutual effects. Next, we established two models to simulate postoperative HCC recurrence: a subcutaneous postoperative recurrence model based on patient-derived tumor xenograft (PDX) tissues and a postoperative recurrence model of orthotopic HCC. By applying these models, the enhanced permeability and retention effect (EPR) based tumor targeting and LA based active targeting can jointly promote the enrichment and uptake of JNPs at tumor site. LA-JNPs represented an efficient targeting system for the co-delivery of Sorafenib/Doxorubicin with an optimized anti-recurrence effect and significantly improved the survival of mice during treatment for postoperative recurrence.

Nanomedicine in Hepatocellular Carcinoma: A New Frontier in Targeted Cancer Treatment

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death and is associated with a dismal median survival of 2-9 months. The fundamental limitations and ineffectiveness of current HCC treatments have led to the development of a vast range of nanotechnologies with the goal of improving the safety and efficacy of treatment for HCC. Although remarkable success has been achieved in nanomedicine research, there are unique considerations such as molecular heterogeneity and concomitant liver dysfunction that complicate the translation of nanotheranostics in HCC. This review highlights the progress, challenges, and targeting opportunities in HCC nanomedicine based on the growing literature in recent years.

Prostate-Specific Membrane Antigen and Esterase Dual Responsive Camptothecin-Oligopeptide Self-Assembled Nanoparticles for Efficient Anticancer Drug Delivery

Background

The clinical utility of camptothecin (CPT) is restricted by poor aqueous solubility, high lipophilicity, active lactone ring instability, and off-targeted toxicities. We report here a prostate-specific membrane antigen (PSMA) and esterase dual responsive self-assembled nanoparticles (CPT-WT-H NPs) for highly efficient CPT delivery and effective cancer therapy.

Methods and Results

In this study, smart self-assembled nanoparticles CPT-WT-H NPs were elaborately designed and synthesized by combing hydrophobic CPT with hydrophilic PSMA-responsive penta-peptide via a cleavable ester bond. This dual responsive nanoparticle with negatively charged surface first respond to the extracellular PSMA and then to the intracellular esterase, achieving a programmable release of CPT at the tumor site and producing the byproducts of biocompatible glutamic acid and aspartic acid. Our data demonstrated that CPT-WT-H NPs exhibited greatly improved water solubility and stability. Results from MTT and flow cytometry showed CPT-WT-H NPs exhibited significantly higher cytotoxicity as well as apoptosis-inducing activity against PSMA-expressing LNCaP-FGC cells than the non-PSMA-expressing cancer cells, showing excellent cytotoxic selectivity. Moreover, the unique nanostructure provided the efficient transportation of CPT to tumor site, which resulted in the effective inhibition of tumor growth and low systemic toxicity in vivo.

Conclusion

CPT-WT-H NPs exhibited excellent in vitro PSMA-response ability and in vivo antitumor activity and safety, holding the promise to become a new and potent anticancer drug. The current research presents a promising strategy for efficient drug delivery.

Polymer-Based Nanosystems-A Versatile Delivery Approach

Polymer-based nanoparticles of tailored size, morphology, and surface properties have attracted increasing attention as carriers for drugs, biomolecules, and genes. By protecting the payload from degradation and maintaining sustained and controlled release of the drug, polymeric nanoparticles can reduce drug clearance, increase their cargo's stability and solubility, prolong its half-life, and ensure optimal concentration at the target site. The inherent immunomodulatory properties of specific polymer nanoparticles, coupled with their drug encapsulation ability, have raised particular interest in vaccine delivery. This paper aims to review current and emerging drug delivery applications of both branched and linear, natural, and synthetic polymer nanostructures, focusing on their role in vaccine development.

Akt inhibition improves the efficacy of cabazitaxel nanomedicine in preclinical taxane-resistant cancer models

Drug resistance remains a major challenge in achieving cures in cancer patients. Cabazitaxel has shown the ability to overcome drug resistance induced by paclitaxel and docetaxel; however, substantially high toxicity has been observed in patients receiving this agent, which compromises its efficacy. We have previously demonstrated that a polymeric platform (termed cabazitaxel-NPs) encapsulating the oligolactide-cabazitaxel conjugate exhibits desired antitumor efficacy and improved in vivo tolerability. However, we found that upon cabazitaxel treatment, cancer cells adapted to activate Akt signaling, which potentially discounts the drug efficacy. We therefore hypothesized that combing cabazitaxel nanotherapeutics with a pan-Akt inhibitor MK-2206 would synergistically sensitize the resistant cancer. In this study, we confirmed that nanoparticle formulation reduced the systemic toxicity, with higher tolerance than solution-based free cabazitaxel agent in animals. Interestingly, the activation of Akt signaling in the resistant cancer was reversed by the addition of MK-2206. In particular, the collaboration of these two ingredients was demonstrated to maximize the efficacy in vitro and in a xenograft model bearing paclitaxel-resistant tumors. Mechanistically, Akt inhibition increased the microtubule-stabilizing effect of cabazitaxel nanomedicine. Collectively, this report introduced a binary platform composed of cytotoxic nanotherapeutics and inhibitors with certain targets to combat multidrug resistance, and such a combined regimen has the potential for the clinical treatment of patients with resistant cancer.

The use of nanotechnology to combat liver cancer: Progress and perspectives

Liver cancer is one of the most common cancers worldwide and is also one of the most difficult cancers to treat, resulting in almost one million deaths per year, and the danger of this cancer is compounded when the tumor is nonresectable. Hepatocellular carcinoma (HCC) is the most common type of liver cancer and has the third highest mortality rate worldwide. Considering the morbid statistics surrounding this cancer it is a popular research topic to target for better therapy practices. This review summarizes the role of nanotechnology in these endeavors. Nanoparticles (NPs) are a very broad class of material and many different kinds have been used to potentially combat liver cancer. Gold, silver, platinum, metal oxide, calcium, and selenium NPs as well as less common materials are all inorganic NPs that have been used as a therapeutic, carrier, or imaging agent in drug delivery systems (DDS) and these efforts are described. Carbon-based NPs, including polymeric, polysaccharide, and lipid NPs as well as carbon dots, have also been widely studied for this purpose and the role they play in DDS for the treatment of liver cancer is illustrated in this review. The multifunctional nature of many NPs described herein, allows these systems to display high anticancer activity in vitro and in vivo and highlights the advantage of and need for combinatorial therapy in treating this difficult cancer. These works are summarized, and future directions are presented for this promising field.

Redox responsive 7-ethyl-10-hydroxycamptothecin (SN38) lysophospholipid conjugate: synthesis, assembly and anticancer evaluation

7-Ethyl-10-hydroxycamptothecin (SN38), a potent camptothecin derivative specifically targeting DNA topoisomerase I cleavage complexes, has shown great potential in the treatment of solid tumors. Because of its poor solubility and chemical and metabolic stability, the clinical application of SN38 is highly limited. To address these problems, a novel redox-responsive SN38 conjugate based liposomal formulation is developed in this report. First, SN38 was conjugated with lysophospholipid by using a cleavable disulfide bond linker. After that, the conjugate (SN38-SS-PC) was assembled into liposomes by thin film method. Dynamic lightscattering(DLS) characterization indicated that SN38-SS-PC liposomes possessed a narrow size distribution (172.8 ± 10.5 nm) and negative charged zeta potential (-8.9 ± 0.3 mV). The results of storage and physiological stabilities showed that SN38-SS-PC liposomes was stable under different conditions. More importantly, a reduction responsive release of parent drug SN38 was observed in the medium containing glutathione (GSH). In addition, SN38-SS-PC liposomes had a much more rapid cellular uptake behavior against cancer cells. The enhanced anti-cancer efficacy of SN38-SS-PC liposomes was further demonstrated by in vitro cytotoxicity assay against MCF-7 and A549 cells. Under in vivo evaluation in 4 T1 xenograft tumor model, SN38-SS-PC liposomes were observed to have lower systemic toxicity and higher tumor inhibition rate of 53.3% compared with the commercialized SN38 prodrug Irinotecan (Ir). In summary, SN38-SS-PC liposomes could be a promising redox responsive delivery system of SN38 for cancer therapy.

A novel GSH-triggered polymeric nanomicelles for reversing MDR and enhancing antitumor efficiency of hydroxycamptothecin

Tumor multidrug resistance (MDR) is one of the main reasons for the failure of clinical chemotherapy. Here, a bio-responsive anti-drug-resistant polymer micelle that can respond to the reductive GSH in the tumor microenvironment (TME) for delivery of HCPT was designed. A new type of polymer with anti-drug resistance and anti-tumor effect was synthesized and used to encapsulated HCPT to form reduction-sensitive micelles (PDSAH) by a thin-film dispersion method. It is demonstrated that the micelle formulation improves the anti-tumor activity and biosafety of HCPT, and also plays a significant role in reversing the drug resistance, which contributes to inhibiting the tumor growth and prolonging the survival time of H22 tumor-bearing mice. The results indicate that this nanoplatform can serve as a flexible and powerful system for delivery of other drugs that are tolerated by tumors or bacteria.

"Sweet tooth"-oriented SN38 prodrug delivery nanoplatform for targeted gastric cancer therapy

Most cancer cells employ overexpression of glucose transports (GLUTs) to satisfy glucose demand ("Sweet Tooth") for increased aerobic glycolysis rates. GLUT1, one of the most widely expressed GLUTs in numerous cancers, was identified as a prognosis-related biomarker of gastric cancer via tissue array analysis. Herein, a "Sweet Tooth"-oriented SN38 prodrug delivery nanoplatform (Glu-SNP) was developed for targeted gastric cancer therapy. For this purpose, a SN38-derived prodrug (PLA-SN38) was synthesized by tethering 7-ethyl-10-hydroxycamptothecin (SN38) to biocompatible polylactic acid (PLA) with the appropriate degree of polymerization (n = 44). The PLA-SN38 conjugate was further assembled with glycosylated amphiphilic lipid to obtain glucosamine-decorated nanoparticles (Glu-SNP). Glu-SNP exhibited potent antitumor efficiency both in vitro and in vivo through enhanced cancer cell-specific targeting associated with the overexpression of GLUT1, which provides a promising approach for gastric cancer therapy.

Repurposing of camptothecin: An esterase-activatable prodrug delivered by a self-emulsifying formulation that improves efficacy in colorectal cancer

The global burden of colorectal cancer (CRC), the third most commonly diagnosed malignancy, continues to rise. Therefore, more effective and less toxic therapies are needed for CRC. CPT-11 (also called irinotecan), the standard-of-care treatment for CRC, has only had limited effects on survival outcomes. In vivo, CPT-11 must be converted to an active metabolite, SN38, to exert antitumor activity in the presence of carboxylesterases, but the conversion rate is extremely low (usually less than 8%). To fully harness the active SN38 compound, we showed here that esterification of SN38 using α-linolenic acid (LNA) generated a prodrug (termed LSN38), which can be formulated in pharmaceutically acceptable surfactants, such as polysorbate 80. Upon blending with an aqueous ethanolic solution, the mixture of LSN38/polysorbate 80 formed self-emulsifying nanomicelles (termed LSN38 NMs), enabling systemic injection. Unlike the insufficient release of active SN38 from CPT-11, drug activation from the LSN38 prodrug was quantitative and relied on esterase, which is abundant in cancerous cells. Pharmacokinetics studies revealed that polysorbate 80-based nanomicelles stably constrained the prodrug in the reservoir and prolonged blood circulation compared to CPT-11. Furthermore, LSN38 NMs showed superior therapeutic efficacy against a colorectal xenograft-bearing mouse model that failed to be treated with clinically approved CPT-11. Overall, these studies highlight the feasibility of converting a chemotherapeutic agent that is not miscible or compatible with pharmaceutical surfactants into an injectable self-emulsifying formulation. This approach could be applied to rescue other drugs or drug candidates that are abandoned in the preclinical stages due to pharmaceutical challenges.

Amphiphilic Janus nanoparticles for imaging-guided synergistic chemo-photothermal hepatocellular carcinoma therapy in the second near-infrared window

Hepatocellular carcinoma (HCC) is one of the most common and deadly malignant tumors worldwide. With unsatisfactory effects of traditional systematic chemotherapy for HCC owing to its drug resistance, novel therapeutic strategies based on nanomaterials for HCC treatments are promising solutions. To solve the challenges of nanoparticles (NPs)-based drug delivery systems for potential clinical applications, we designed water soluble amphiphilic oleic acid-NaYF4:Yb,Er/polydopamine Au nanoflower Janus NPs (OA-UCNPs/PDA-AuF JNPs) with discrete multi compartment nanostructures as dual-drug delivery systems (DDDSs). This unique nanostructure meets the requirements for containing hydrophobic hydroxycamptothecin/hydrophilic doxorubicin in divided spaces and releasing each drug from non-interfering channels under pH/near-infrared (NIR) dual-stimuli. The amphiphilic DDDSs were utilized to eradicate the tumor burden on a high-fidelity HCC model of a patient-derived xenograft (PDX), and represented an efficient strategy for defeating HCC using multi-modal imaging-guided dual-drug chemo-photothermal therapy in the second NIR window. In addition, the potential mechanisms of action for the DDDSs were evaluated.

Balancing the stability and drug activation in adaptive nanoparticles potentiates chemotherapy in multidrug-resistant cancer

Rationale: Prodrug strategies that render the drug temporarily inactive through a cleavable linkage are able to modulate the physicochemical properties of drugs for adaptive nanoparticle (NP) formulation. Here we used cabazitaxel as a model compound to test the validity of our "balancing NP stability and specific drug activation" strategy. Methods: Cabazitaxel is conjugated to hydrophobic polylactide fragments with varying chain lengths via a self-immolation linkage, yielding polymeric prodrugs that can be reactivated by reductive agents in cells. Following a nanoprecipitation protocol, cabazitaxel prodrugs can be stably entrapped in amphiphilic polyethylene-block-polylactide matrices to form core-shell nanotherapies with augmented colloidal stability. Results: Upon cellular uptake followed by intracellular reduction, the NPs spontaneously release chemically unmodified cabazitaxel and exert high cytotoxicity. Studies with near-infrared dye-labeled NPs demonstrate that the nanodelivery of the prodrugs extends their systemic circulation, accompanied with increased drug concentrations at target tumor sites. In preclinical mouse xenograft models, including two paclitaxel-resistant xenograft models, the nanotherapy shows a remarkably higher efficacy in tumor suppression and an improved safety profile than free cabazitaxel. Conclusion: Collectively, our approach enables more effective and less toxic delivery of the cabazitaxel drug, which could be a new generalizable strategy for re-engineering other toxic and water-insoluble therapeutics.

Colon tissue-accumulating mesoporous carbon nanoparticles loaded with Musca domestica cecropin for ulcerative colitis therapy

Ulcerative colitis (UC) is a modern refractory disease with steadily increasing incidence worldwide that urgently requires effective and safe therapies. Therapeutic peptides delivered using nanocarriers have shown promising developments for the treatment of UC. We developed a novel colon-accumulating oral drug delivery nanoplatform consisting of Musca domestica cecropin (MDC) and mesoporous carbon nanoparticles (MCNs) and investigated its effects and mechanism of action for the treatment of UC. Methods: An optimized one-step soft templating method was developed to synthesize MCNs, into which MDC was loaded to fabricate MDC@MCNs. MCNs and MDC@MCNs were characterized by BET, XRD, and TEM. MDC and MDC@MCNs resistance to trypsin degradation was measured through Oxford cup antibacterial experiments using Salmonella typhimurium as the indicator. Uptake of MDC and MDC@MCNs by NCM460 cells was observed by fluorescence microscopy. The biocompatibility of MDC, MCNs, and MDC@MCNs was evaluated in three cell lines (NCM460, L02, and NIH3T3) and C57BL/6 mice. Dextran sulphate sodium was used to establish models of NCM460 cell injury and UC in mice. MTT assay, flow cytometry, and mitochondrial membrane potential assay were applied to determine the effects of MDC@MCNs on NCM460 cells injury. Additionally, a variety of biological methods such as H&E staining, TEM, ELISA, qPCR, Western blotting, and 16s rDNA sequencing were performed to explore the effects and underlying mechanism of MDC@MCN on UC in vivo. Colonic adhesion of MCNs was compared in normal and UC mice. The oral biodistributions of MDC and MDC@MCNs in the gastrointestinal tract of mice were also determined. Results: MDC@MCNs were successfully developed and exhibited excellent ability to resist destruction by trypsin and were taken up by NCM460 cells more readily than MDC. In vitro studies showed that MDC@MCNs better inhibited DSS-induced NCM460 cells damage with lower toxicity to L02 and NIH3T3 cells compared with MDC. In vivo results indicated that MDC@MCNs have good biocompatibility and significantly improved colonic injury in UC mice by effectively inhibiting inflammation and oxidative stress, maintaining colonic tight junctions, and regulating intestinal flora. Moreover, MDC@MCNs were strongly retained in the intestines, which was attributed to intestinal adhesion and aggregation of MCNs, serving as one of the important reasons for its enhanced efficacy after oral administration compared with MDC. Conclusion: MDC@MCNs alleviated DSS-induced UC by ameliorating colonic epithelial cells damage, inhibiting inflammation and oxidative stress, enhancing colonic tight junctions, and regulating intestinal flora. This colon-accumulating oral drug delivery nanoplatform may provide a novel and precise therapeutic strategy for UC.

In situ activation of STING pathway with polymeric SN38 for cancer chemoimmunotherapy

STING (stimulator of interferon genes) signaling pathway has attracted considerable attention in cancer immunotherapy due to its capacity to boost vigorous antitumor immunity. However, the shortage of effective STING agonists limits the promotion of STING pathway in cancer treatment. Herein, we present an approach for in situ activation of STING pathway with nanoparticles delivered DNA-targeting chemo agents, based on the understanding that cytosol DNA is a pre-requisite for STING pathway activation. Through in vitro screening among several DNA-targeting chemo agents, we identified 7-ethyl-10-hydroxycamptothecin (SN38) as the most potent drug for stimulating interferon (IFN)-β secretion and proved that this process is mediated by the passage of DNA-containing exosomes from treated tumor cells to bone marrow-derived dendritic cells (BMDCs) and subsequent activation of the STING pathway. Furthermore, we designed a polymeric-SN38 conjugate that could self-assemble into nanoparticles (SN38-NPs) for in vivo application. The SN38-NPs formulation reduced toxicity of free SN38, effectively stimulated the activation of STING pathway in E0771 tumors, and resulted in a tumor suppression rate (TSR%) of 82.6%. Our results revealed a new mechanism of SN38 in cancer treatment and should inspire using more DNA-targeting agents, especially in nanoformulation, for activating STING pathway and cancer chemoimmunotherapy.

Nanostructure of DiR-Loaded Solid Lipid Nanoparticles with Potential Bioimaging Functions

The fluorescence dye-loaded nanoparticles are widely used as bioimaging agents in the field of nanotheranostics. However, the nanoparticles for nanotheranostics usually consist of synthetic materials, such as metal, silica, and organic polymers, which are often biologically incompatible and may arouse toxicity issues. Herein, the potential of near-infrared probe DiR-containing solid lipid nanoparticle suspensions (DiR-SLNS) as the bioimaging agent, which was prepared by lipids and surfactants with excellent biocompatibility, was investigated in this study. The nanostructure of DIR-SLNS system and the distribution of DiR were studied by dissipative particle dynamics (DPD) simulations. The stability of physicochemical properties and fluorescence spectra of DIR-SLNS system were investigated using dynamic laser scattering (DLS), nanoparticle tracking analysis (NTA), and fluorescence spectra. The fluorescence intensity-concentration correlation of DIR-SLNS was also evaluated. As a result, DiR-SLNS demonstrated a "core-shell"-like nanostructure and DiR was mainly distributed in the cetyl palmitate (CP) core rather than the surface of SLNS, which was beneficial to its potential applications in bioimaging. DiR-SLNS exhibited remarkable physicochemical stability as the nanoparticles maintained ~ 90% fluorescence intensity during the 10-day storage time. The correlation between fluorescence intensity and concentration was established and validated using a linear regression model. This study proposed a type of promising candidates in nano-scale with higher safety and fluorescence stability for bioimaging.

Acyl and oligo(lactic acid) prodrugs for PEG-b-PLA and PEG-b-PCL nano-assemblies for injection

Poly(ethylene glycol)-block-poly(D,L-lactic acid) (PEG-b-PLA) and poly(ethylene glycol)-block-poly(ε-caprolactone) (PEG-b-PCL) form nano-assemblies, including micelles and nanoparticles, that increase the water solubility of anticancer drugs for injection. PEG-b-PLA and PEG-b-PCL are less toxic than commonly used organic solvents or solubilizers for injection, such as Cremophor EL® in Taxol®. Formulating paclitaxel in PEG-b-PLA micelles, as Genexol-PM®, permits dose escalation over Taxol®, enhancing antitumor efficacy in breast, lung and ovarian cancers. To expand the repertoire of anticancer drugs for injection, acyl and oligo(lactic acid) ester prodrugs have been synthesized for PEG-b-PLA and PEG-b-PCL nano-assemblies, compatibility, and novel nanomedicines for injection. Notably, acyl and oligo(lactic acid) taxane prodrugs delivered by PEG-b-PLA and PEG-b-PCL nano-assemblies display heightened plasma exposure, reduction in biodistribution into major organs and enhanced tumor exposure in murine tumor models, versus parent anticancer drugs in conventional formulations. As a result, acyl and oligo(lactic acid) ester prodrugs are less toxic and induce durable antitumor responses. In summary, acyl and oligo(lactic acid) ester prodrugs widen the range of anticancer drugs that can be tested safely and effectively by using PEG-b-PLA and PEG-b-PCL nano-assemblies, and they display superior anticancer efficacy over parent anticancer drugs, which are often approved products. Oligo(lactic acid) ester taxane prodrugs are in pre-clinical development as novel drug combinations and immunotherapy combinations for cancer therapy.

Nanotechnology-based drug delivery systems for enhanced diagnosis and therapy of oral cancer

Oral cancer is a common malignant life-threatening tumor. Despite some advances in traditional therapy, mortality and mobidity rates are high due to delayed diagnosis and ineffective treatment. Additionally, some patients inevitably suffer from various fatal adverse effects during the course of therapy. Therefore, it is imperative to develop novel methods to eradicate oral cancer cells with minimal adverse effects on normal cells. Nanotechnology is a promising and novel vehicle for the diagnosis and treatment of oral cancer with encouraging recent achievements. In this review, we present state-of-the-art nanotechnology-based drug delivery systems employed in the domain of oral cancer, especially for its enhanced diagnosis and therapy. We describe in detail the types of nanotechnology used in the management of oral cancer and summarize administration routes of nanodrugs. Finally, the potential and prospects of nanotechnology-based drug delivery systems as promising modalities of diagnosis and therapy of oral cancer are highlighted.

Novel fast-acting pyrazole/pyridine-functionalized N-heterocyclic carbene silver complexes assembled with nanoparticles show enhanced safety and efficacy as anticancer therapeutics

In this study, we designed and synthesized four novel multi-nuclear silver complexes (1-4) coordinated with pyrazole- or pyridine-functionalized N-heterocyclic carbene (NHC) ligands. The crystal structures of the silver-NHC complexes were confirmed by X-ray diffraction analysis. In vitro assays showed that the silver-NHC complexes effectively killed a broad range of cancer cells after short-term drug exposure, serving as fast-acting cytotoxic agents. Of note, in cisplatin-resistant A549 cancer cells, the silver complexes were not cross-resistant with the clinically used cisplatin agent. Detailed mechanistic studies revealed that complex 2 triggered caspase-independent cell necrosis associated with intracellular reactive oxygen species (ROS) production and mitochondrial membrane potential (MMP) depletion. By exploiting a facile nano-assembly process, silver-NHC complexes 1, 2 and 4 were successfully integrated into the hydrophobic cores of amphiphilic matrices (DSPE-PEG2K), enabling systemic injection. The silver complex-loaded nanotherapeutics (1-NPs, 2-NPs, and 4-NPs) showed high safety margins with reduced systemic drug toxicities relative to cisplatin in animals. Furthermore, in a xenograft model of human colorectal cancer, the administration of the nanotherapeutics resulted in a marked inhibition of tumor progression.

New Organometallic Ruthenium(II) Compounds Synergistically Show Cytotoxic, Antimetastatic and Antiangiogenic Activities for the Treatment of Metastatic Cancer

In this study, we newly designed and synthesized a small library of ten structurally related C,N-cyclometalated ruthenium(II) complexes containing various pyridine-functionalized NHC ligand and chelating bipyridyl ligands (e.g., 2,2'-bipyridine, 5,5'-dimethyl-2,2'-bipyridine, and 1,10-phenanthroline (phen)). The complexes were well characterized by NMR, electrospray ionization-mass spectrometry, and single-crystal X-ray structure analyses. Among the new ruthenium(II) derivatives, we identified that the complex Ru8 bearing bulky moieties (i.e., phen and pentamethyl benzene) had the most potent cytotoxicity against all tested cancer cell lines, generating dose- and cell line-dependent IC₅₀ values at the range of 3.3-15.0 μm. More significantly, Ru8 not only efficiently inhibited the metastasis process against invasion and migration of tumor cells but also exhibited potent antivascular effects by suppressing HUVEC cells migration and tube formation in vitro and blocking vessel generation in vivo (chicken chorioallantoic membrane model). In a metastatic A2780 tumor xenograft-bearing mouse model, administration of Ru8 outperformed antimetastatic agent NAMI-A and clinically approved cisplatin in terms of antitumor efficacy and inhibition of metastases to other organs. Overall, these data provided compelling evidence that the new cyclometalated ruthenium complex Ru8 is an attractive agent because of synergistically suppressing bulky tumors and metastasized tumor nudes. Therefore, the complex Ru8 deserves further investigations.

HTBPI, an active phenanthroindolizidine alkaloid, inhibits liver tumorigenesis by targeting Akt

Akt, a crucial protein involved in a variety of signaling pathways in cancer, acts as an important regulator of survival in hepatocellular carcinoma (HCC), and provides curative option for the related drugs development. We have found an active phenanthroindolizidine alkaloid, (13aR,14R)-9,11,12,13,13a,14-hexahydro-3,6,7-trimethoxydibenzo[f,h]pyrrolo[1,2-b]isoquinolin-14-ol (HTBPI), is a promising Akt inhibitor effective in the suppression of HCC cells proliferation through stimulating apoptotic and autophagic capability in vivo and in vitro. Treatment of HTBPI combined with a classical autophagy-lysosomal inhibitor (bafilomycin A1), could enhance stimulation effects of apoptosis on HCC cell lines. In addition, we confirmed HTBPI targeting Akt, occupied the kinase binding domain (Thr 308) of Akt to inactivate its function by CETSA and DARTS assay. In contrast, ectopic Akt-induced overexpression significantly abrogated inhibitory effects of HTBPI on cell viability and proliferation. Furthermore, high p-Akt (Thr 308) expression is collated with liver tumor formation and poor survival in HCC patients. In conclusions, HTBPI impeded HCC progress through regulation of apoptosis and autophagy machinery via interaction with p-Akt (Thr 308). This may provide potential molecular candidate by targeting Akt for the therapy of HCC patients.

A novel oncolytic adenovirus inhibits hepatocellular carcinoma growth

OBJECTIVE

To evaluate the inhibitory role of a novel oncolytic adenovirus (OA), GP73-SphK1sR-Ad5, on the growth of hepatocellular carcinoma (HCC).

METHODS

GP73-SphK1sR-Ad5 was constructed by integrating Golgi protein 73 (GP73) promoter and sphingosine kinase 1 (SphK1)-short hairpin RNA (shRNA) into adenovirus serotype 5 (Ad5), and transfecting into HCC Huh7 cells and normal human liver HL-7702 cells. The expression of SphK1 and adenovirus early region 1 (E1A) was detected by quantitative real-time PCR (qRT-PCR) and western blot, respectively. Cell viability was detected by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay, and apoptotic rate was determined by flow cytometry. An Huh7 xenograft model was established in mice injected intratumorally with GP73-SphK1sR-Ad5. Twenty days after injection, the tumor volume and weight, and the survival time of the mice were recorded. The histopathological changes in tumor tissues were observed by hematoxylin-eosin (HE) staining and transmission electron microscopy (TEM).

RESULTS

Transfection of GP73-SphK1sR-Ad5 significantly upregulated E1A and downregulated SphK1 in Huh7 cells, but not in HL7702 cells. GP73-SphK1sR-Ad5 transfection significantly decreased the viability and increased the apoptotic rate of Huh7 cells, but had no effect on HL7702 cells. Intratumoral injection of GP73-SphK1sR-Ad5 into the Huh7 xenograft mouse model significantly decreased tumor volume and weight, and prolonged survival time. It also significantly decreased the tumor infiltration area and blood vessel density, and increased the percentages of cells with nucleus deformation and cells with condensed chromatin in tumor tissues.

CONCLUSIONS

GP73-SphK1sR-Ad5 serves as a novel OA and can inhibit HCC progression with high specificity and efficacy.

Transforming a toxic drug into an efficacious nanomedicine using a lipoprodrug strategy for the treatment of patient-derived melanoma xenografts

Despite the progress made with the recent clinical use of the anticancer compound cabazitaxel, the efficacy in patients remains unsatisfactory, largely due to the high in vivo toxicity of the agent. Therefore, strategies that achieve favorable outcomes and good safety profiles will greatly expand the repertoire of this potent agent. Here, we propose a combinatorial strategy to reform the cabazitaxel agent and the use of sequential supramolecular nanoassembly with liposomal compositions to assemble a prodrug-formulated liposome, termed lipoprodrug, for safe and effective drug delivery. Reconstructing cabazitaxel with a polyunsaturated fatty acid (i.e., docosahexaenoic acid) via a hydrolyzable ester bond confers the generated prodrug with the ability to be readily integrated into the lipid bilayer of liposomes for systemic administration. The resulting lipoprodrug scaffold showed significantly sustained drug release profiles and improved pharmacokinetics in rats as well as a reduction in systemic toxicity in vivo. Notably, the lipoprodrug outperformed free cabazitaxel in terms of in vivo therapeutic efficacy in multiple separate tumor xenograft-bearing mouse models, one of which was a patient-derived xenograft model. Surprisingly, the lipoprodrug was able to reduce tumor invasiveness and reprogram the tumor immunosuppressive microenvironment by proinflammatory macrophage polarization. Our findings validate this lipoprodrug approach as a simple yet effective strategy for transforming the highly toxic cabazitaxel agent into an efficacious nanomedicine with excellent in vivo tolerability. This approach could also be applied to rescue other drugs or drug candidates that have failed in clinical trials due to poor pharmacokinetic properties or unacceptable toxicity in patients.

Formulation and characterization of folate receptor-targeted PEGylated liposome encapsulating bioactive compounds from Kappaphycus alvarezii for cancer therapy

This study aimed to formulate and characterize the folate receptor-targeted PEGylated liposome encapsulating bioactive compounds from Kappaphycus alvarezii to enhance the anticancer activity. Twenty valued bioactive compounds (3-hydroxy benzoicacid, gallicacid, chlorogenicacid, cinnamicacid, artemiseole, hydrazine carbothioamide, etc.,) are confirmed from methanol extract of K. alvarezii using analytical techniques like HPLC and GC-MS. The delivery of bioactive compounds of K. alvarezii via naturally overexpressed folate receptor (FR) to FR-positive breast cancer cells was studied. FR targeted PEGylated liposome was constructed by modified thin-film hydration technique using FA-PEG-DSPE/cholesterol/DSPC (5:40:55) and bioactive compounds of K. alvarezii was encapsulated. Their morphology, size, shape, physiological stability and drug release kinetics were studied. The study reports of K. alvarezii extract-encapsulated PEGylated liposome showed spherical shaped particles with amorphous in nature. The mean diameter of K. alvarezii extract-encapsulated PEGylated and FA-conjugated PEGylated liposomes was found to be 110 ± 6 nm and 140 ± 5 nm, respectively. Based on the stability studies, it could be confirmed that FA-conjugated PEGylated liposome was highly stable in various physiological buffer medium. FA-conjugated PEGylated liposome can steadily release the bioactive compounds of K. alvarezii extract in acidic medium (pH 5.4). MTT assay demonstrated the concentration-dependent cytotoxicity against MCF-7 cells after 24 h with IC₅₀ of 81 µg/mL. Also, PEGylated liposome enhanced the delivery of K. alvarezii extract in MCF-7 cells. After treatment, typical apoptotic morphology of condensed nuclei and distorted membrane bodies was picturized. Additionally, PEGylated liposome targets the mitochondria of MCF-7 cells and significantly increased the level of ROS and contributes to the damage of mitochondrial transmembrane potential. Hence, PEGylated liposome could positively deliver the bioactive compounds of K. alvarezii extract into FR-positive breast cancer cells (MCF-7) and exhibit great potential in anticancer therapy.

Layered double hydroxide nanosheets: towards ultrasensitive tumor microenvironment responsive synergistic therapy

The tumor microenvironment (TME), which is characterised by high H₂O₂ and glutathione (GSH) levels, low pH value and hypoxia, imposes crucial influences on tumor therapeutic outcomes. Rational design and preparation of nanomaterial systems that are responsive to the intrinsic properties of the TME open a promising avenue towards tumor-specific treatment. Herein, CoMn-layered double hydroxide (CoMn-LDH) nanosheets were synthesized via a bottom-up method followed by surface modification with a photosensitizer, chlorin e6 (Ce6), which exhibited TME-responsive imaging as well as photodynamic and chemodynamic synergistic therapy (PDT/CDT). Due to their ultralow bond energy and large adsorption energy, CoMn-LDH nanosheets show fast self-degradability in a GSH (10 mM) microenvironment, giving an excellent CDT activity in mildly acidic conditions (pH = 6.5), superior GSH removal ability (99.82%) and O₂ production (35.37 μg L^-1 s^-1). Moreover, Ce6/CoMn-LDH nanosheets display satisfactory photoacoustic (PA) imaging and GSH-enhanced magnetic resonance imaging (MRI) with a 45.1-fold T₁-enhancement. In addition, both in vitro and in vivo therapeutic tests based on Ce6/CoMn-LDH demonstrate a satisfactory anticancer activity with complete cancer cell apoptosis and dramatic tumor elimination. This work provides a new perspective for the design of multifunctional 2D nanosheets towards a fully promoted TME-responsive synergistic therapy, which holds great promise for future clinical diagnosis and treatment.

Supramolecular Engineering of Molecular Inhibitors in an Adaptive Cytotoxic Nanoparticle for Synergistic Cancer Therapy

Combinatorial regimens that rationally pair molecular inhibitors with standard cytotoxic chemotherapeutics are used to improve therapeutic outcomes. Simultaneously engineering these therapies within a single nanocarrier that spans cytotoxic, antiangiogenic, and anti-invasive mechanisms and that enables the delivery of unique drug combinations remains a technical challenge. In this study, we developed a simple and broadly applicable strategy in which ultrastable cytotoxic nanoparticles with an established excellent antitumor efficacy and π-rich inner core structure supramolecularly stabilized the antiangiogenic molecular inhibitor apatinib to create a synergistic drug delivery system (termed sTKI-pSN38). This small-sized nanoparticle accomplished the sequential release of both encapsulated drugs to exert antimetastatic, antivascular, and cytotoxic activities simultaneously. In xenograft models of hepatocellular carcinoma, a single intravenous administration of sTKI-pSN38 elicited robust and durable tumor reduction and suppressed metastasis to lymph nodes. Interestingly, sTKI-pSN38 treatment alleviated intratumoral hypoxia, which could contribute to impaired tumor metastasis and reduced drug resistance. Collectively, this nanotherapeutic platform offers a new strategy for cancer therapy by simply engineering a drug cocktail in conventional nanoparticles and by enabling the spatiotemporal modulation of drug release to enhance the synergy of the combined drugs.

Liver Cancer: Current and Future Trends Using Biomaterials

Hepatocellular carcinoma (HCC) is the fifth most common type of cancer diagnosed and the second leading cause of death worldwide. Despite advancement in current treatments for HCC, the prognosis for this cancer is still unfavorable. This comprehensive review article focuses on all the current technology that applies biomaterials to treat and study liver cancer, thus showing the versatility of biomaterials to be used as smart tools in this complex pathologic scenario. Specifically, after introducing the liver anatomy and pathology by focusing on the available treatments for HCC, this review summarizes the current biomaterial-based approaches for systemic delivery and implantable tools for locally administrating bioactive factors and provides a comprehensive discussion of the specific therapies and targeting agents to efficiently deliver those factors. This review also highlights the novel application of biomaterials to study HCC, which includes hydrogels and scaffolds to tissue engineer 3D in vitro models representative of the tumor environment. Such models will serve to better understand the tumor biology and investigate new therapies for HCC. Special focus is given to innovative approaches, e.g., combined delivery therapies, and to alternative approaches-e.g., cell capture-as promising future trends in the application of biomaterials to treat HCC.

Self-assembling poly(ethylene glycol)-block-polylactide-cabazitaxel conjugate nanoparticles for anticancer therapy with high efficacy and low in vivo toxicity

Traditional approaches used for transforming hydrophobic anticancer drugs into therapeutically available nanoparticles heavily rely on the noncovalent formulation of drugs within amphiphilic copolymers. However, these nanotherapies have not yet shown the expected favorable clinical outcomes in cancer patients, presumably due to their insufficient stability. To solve this dilemma, we conceive a new class of nanotherapies assembled with polymeric prodrugs that maintain pharmacological activity while substantially alleviate the drug toxicity in animals. By exploiting methoxypoly(ethylene glycol)-block-poly(D, L-lactic acid) (mPEG-PLA) as a promoiety, cabazitaxel is tethered to the terminus of the PLA fragment via a hydrolysable ester linkage. These conjugates recapitulate the self-assembly to produce colloidal stable nanotherapies. In a xenograft model of prostate cancer, this nanotherapy shows a durable inhibition of tumor progression upon the administration of a tolerable dose. Our results suggest that a hydrophobic and highly toxic drug can be rationally converted into a pharmacologically efficient and self-deliverable nanotherapy.

Dual functional matrix metalloproteinase-responsive curcumin-loaded nanoparticles for tumor-targeted treatment

The limitations of anticancer drugs, including poor tumor targeting and weak uptake efficiency, are important factors affecting tumor therapy. According to characteristics of the tumor microenvironment, in this study, we aimed to synthesize matrix metalloproteinase (MMP)-responsive curcumin (Cur)-loaded nanoparticles (Cur-P-NPs) based on amphiphilic block copolymer (MePEG-peptide-PET-PCL) with MMP-cleavable peptide (GPLGIAGQ) and penetrating peptide (r9), modified to improve tumor targeting and cellular uptake. The average size of Cur-P-NPs was 176.9 nm, with a zeta potential of 8.1 mV, and they showed drug entrapment efficiency and a loading capacity of 87.07% ± 0.63% and 7.44% ± 0.16%, respectively. Furthermore, Cur release from Cur-P-NPs was sustained for 144 h at pH 7.4, and the release rate was accelerated under enzyme reaction condition. The MTT assay demonstrated that free P-NPs had favorable biosafety, and the anti-proliferative activity of Cur-P-NPs was positively correlated with Cur concentration in MCF-7 cells. Additionally, the results of cellular uptake, in vivo pharmacokinetics, and biodistribution showed that Cur-P-NPs had a good effect on cellular uptake and tumor targeting, resulting in the best bioavailability in tumor therapy. Therefore, Cur-P-NPs, as a promising drug delivery system, might lead to a new and efficient route for targeted therapy in clinical practice.

Right Cu2- x S@MnS Core-Shell Nanoparticles as a Photo/H2O2-Responsive Platform for Effective Cancer Theranostics

Stimuli-responsive nanomedicines have become a recent research focus as a candidate for cancer treatment because of their effectiveness, sensibility, and minimal invasiveness. In this work, a novel nanosystem is developed based on Cu2- x S@MnS core-shell nanoparticles (CSNPs) in which the Cu2- x S core serves as a photosensitizer to generate hyperthermia and reactive oxygen species (ROS), and the MnS shell is used in H2O2-responsive O2 production. Cu2 -x S@MnS CSNPs with an independent core and shell ratio are synthesized by a controllable hot-injection method, resulting in an optimal photothermal (PT) effect with a PT conversion efficiency of up to 47.9%. An enhanced photodynamic (PD) effect also occurs in an H2O2 environment. More significantly, in vivo experiments demonstrate that Cu2 -x S@MnS CSNPs can mediate tumor shrinkage in both HeLa tumor cell line-derived xenograft (CDX) and head and neck squamous cell carcinoma (HNSCC) patient-derived xenograft (PDX) models, with the capability of being used as a T1-enhanced magnetic resonance (MR) contrast agent. These results suggest the great potential of as-prepared Cu2 -x S@MnS CSNPs as photo/H2O2-responsive therapeutic-agents against tumors, even in a complicated and heterogeneous environment, thus promoting the clinical translation of nanomedicine.

Orally Deliverable Nanotherapeutics for the Synergistic Treatment of Colitis-Associated Colorectal Cancer

Purpose: Colitis-associated colorectal cancer (CAC) poses substantial challenges for effective treatment. Currently, there is a considerable need for the development of orally bioavailable dosage forms that enable the safe and effective delivery of therapeutic drugs to local diseased lesions in the gastrointestinal tract. Experimental Design: In this study, we developed orally deliverable nanotherapeutics for the synergistic treatment of inflammatory bowel diseases (IBDs) and CAC. Water-insoluble curcumin (CUR) and 7-ethyl-10-hydroxycamptothecin (SN38), which served as anti-inflammatory and cytotoxic agents, respectively, were chemically engineered into hydrophilic mucoadhesive chitosan for the generation of chitosan-drug amphiphiles. Results: The resulting amphiphilic constructs formed core-shell nanostructures in aqueous solutions and were orally administered for in vivo therapeutic studies. Using a preclinical CAC mouse model, we showed that the orally delivered nanotherapeutics locally accumulated in inflamed intestinal regions and tumor tissues. Furthermore, the therapeutic synergy of the combined nanotherapeutics in CAC mice was evaluated. Compared with their individual drug forms, combined CUR and SN38 nanoparticles yielded synergistic effects to alleviate intestinal inflammation and protect mice from ulcerative colitis. Notably, the combinatorial therapy demonstrated a remarkable tumor shrinkage with only ~6% of the total tumors exceeding 4 mm in diameter, whereas ~35% of tumors were observed to exceed a diameter of 4 mm in the saline-treated CAC mice. These data suggest a new and reliable approach for improving the treatment of IBD and CAC. Conclusions: Our results showed that bioadhesive chitosan materials can be used to produce colloidal-stable nanotherapeutics that are suitable for oral delivery. Both nanotherapeutics exhibited substantial accumulation in inflamed intestinal regions and tumor tissues and showed good synergy for treating CAC, warranting further clinical translation.