Molecularly targeted co-delivery of a histone deacetylase inhibitor and paclitaxel by lipid-protein hybrid nanoparticles for synergistic combinational chemotherapy

Injectable dual thermoreversible hydrogel for sustained intramuscular drug delivery

Herein, we reported novel docetaxel-decorated solid lipid nanoparticle (DCT-SLN)-loaded dual thermoreversible system (DCT-DRTS) for intramuscular administration with reduced burst effect, sustained release and improved antitumor efficacy. The optimized DCT-DRTs was subjected to in-vitro and in-vivo analyses. Antitumor evaluation of the DCT-DRTS was executed and compared with DCT-hydrogel, and DCT-suspension trailed by the histopathological and immune-histochemical analyses. The DCT-SLN gave a mean particle size of 157 nm and entrapment efficiency of 93 %. It was a solid at room temperature, and changed to liquid at physiological temperature due to its melting point of about 32 °C. Unlikely, poloxamer mixture remained liquefied at 25-27 °C, however converted to gel at physiological temperature. This behavior demonstrated opposed reversible property of the DCT-SLN and poloxamer hydrogel in DCT-DRTS system, making it ideal for intramuscular administration and quick gelation inside the body. The DCT-DRTS sustained the drugs release and unlike DCT-hydrogel, the preliminary plasma concentration of DCT-DRTS was significantly reduced, overcoming the burst release. A meaningfully enhanced antitumor efficacy and improved survival rate was observed from DCT-DRTS in tumor cell xenograft athymic nude mice. Additionally, increased apoptotic and reduced proliferation markers were observed in DCT-DRTS treated tumor masses. It was concluded that DCT-DRTS may be a suitable choice for intramuscular administration of DCT with sustained release, improved bioavailability, reduced toxicity and enhanced antitumor effects.

Exploring the synergistic behavior of paclitaxel and vorinostat upon co-loading in albumin nanoparticles for breast cancer management

Breast cancer is challenging to treat accompanied with poor clinical outcomes. Paclitaxel (PTX) is a first-line chemotherapeutic agent, but possesses limitations due to side effects, high dose, non-specific tissue distribution, and drug resistance. An epigenetic modulator, vorinostat (VOR) is known to enhance PTX efficacy and therefore to resolve the issues of conventional PTX formulations, we designed PTX- and VOR-bound albumin nanoparticles (PTX-VOR-BSA-NPs) using antisolvent precipitation technique where albumin is used as a carrier and a targeting agent. The PTX-VOR-BSA-NPs were of 140 nm size, polydispersity index around 0.18, and about 78% and 68% of entrapment efficiency for PTX and VOR, respectively. A bi-pattern release of both PTX and VOR was observed from PTX-VOR-BSA-NPs with a burst release for 2 h succeeded by sustained release until 24 h. A significantly lower %cell viability was observed in MCF-7 cell lines, while efficient cellular drug uptake was found in MDA-MB-231 cells. Furthermore, a greater apoptotic index was found compared to free PTX and VOR because of the synergistic activity of these drugs. The PTX-VOR-BSA-NPs also showcased superior pharmacokinetic profile and noteworthy reduction in the tumor volume compared to Intaxel in 4T1 cell line-induced breast tumor model. Further, the NPs showed similar levels of toxicity biomarkers as that of control. Overall, the developed PTX-VOR-BSA-NPs were found to have less toxicity and more effectiveness compared to the marketed formulation, thus affirming the generation of a potent as well as and safe product.

Recent advances of novel targeted drug delivery systems based on natural medicine monomers against hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the most prevalent type of liver cancer, is often diagnosed at an advanced stage. Surgical interventions are often ineffective, leading HCC patients to rely on systemic chemotherapy. Unfortunately, commonly used chemotherapeutic drugs have limited efficacy and can adversely affect vital organs, causing significant physical and psychological distress for patients. Natural medicine monomers (NMMs) have shown promising efficacy and safety profiles in HCC treatment, garnering attention from researchers. In recent years, the development of novel targeted drug delivery systems (TDDS) combining NMMs with nanocarriers has emerged. These TDDS aim to concentrate drugs effectively in HCC cells by manipulating the characteristics of nanomedicines, leveraging receptor and ligand interactions, and utilizing endogenous stimulatory responses to promote specific nanomedicines distribution. This comprehensive review presents recent research on TDDS for HCC treatment using NMMs from three perspectives: passive TDDS, active TDDS, and stimuli-responsive drug delivery systems (SDDS). It consolidates the current state of research on TDDS for HCC treatment with NMMs and highlights the potential of these innovative approaches in improving treatment outcomes. Moreover, the review also identifies research gaps in the related fields to provide references for future targeted therapy research in HCC.

Lipid polymer hybrid nanoparticles: a custom-tailored next-generation approach for cancer therapeutics

Lipid-based polymeric nanoparticles are the highly popular carrier systems for cancer drug therapy. But presently, detailed investigations have revealed their flaws as drug delivery carriers. Lipid polymer hybrid nanoparticles (LPHNPs) are advanced core-shell nanoconstructs with a polymeric core region enclosed by a lipidic layer, presumed to be derived from both liposomes and polymeric nanounits. This unique concept is of utmost importance as a combinable drug delivery platform in oncology due to its dual structured character. To add advantage and restrict one's limitation by other, LPHNPs have been designed so to gain number of advantages such as stability, high loading of cargo, increased biocompatibility, rate-limiting controlled release, and elevated drug half-lives as well as therapeutic effectiveness while minimizing their drawbacks. The outer shell, in particular, can be functionalized in a variety of ways with stimuli-responsive moieties and ligands to provide intelligent holding and for active targeting of antineoplastic medicines, transport of genes, and theragnostic. This review comprehensively provides insight into recent substantial advancements in developing strategies for treating various cancer using LPHNPs. The bioactivity assessment factors have also been highlighted with a discussion of LPHNPs future clinical prospects.

Nanomedicine and epigenetics: New alliances to increase the odds in pancreatic cancer survival

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers worldwide, primarily due to its robust desmoplastic stroma and immunosuppressive tumor microenvironment (TME), which facilitate tumor progression and metastasis. In addition, fibrous tissue leads to sparse vasculature, high interstitial fluid pressure, and hypoxia, thereby hindering effective systemic drug delivery and immune cell infiltration. Thus, remodeling the TME to enhance tumor perfusion, increase drug retention, and reverse immunosuppression has become a key therapeutic strategy. In recent years, targeting epigenetic pathways has emerged as a promising approach to overcome tumor immunosuppression and cancer progression. Moreover, the progress in nanotechnology has provided new opportunities for enhancing the efficacy of conventional and epigenetic drugs. Nano-based drug delivery systems (NDDSs) offer several advantages, including improved drug pharmacokinetics, enhanced tumor penetration, and reduced systemic toxicity. Smart NDDSs enable precise targeting of stromal components and augment the effectiveness of immunotherapy through multiple drug delivery options. This review offers an overview of the latest nano-based approaches developed to achieve superior therapeutic efficacy and overcome drug resistance. We specifically focus on the TME and epigenetic-targeted therapies in the context of PDAC, discussing the advantages and limitations of current strategies while highlighting promising new developments. By emphasizing the immense potential of NDDSs in improving therapeutic outcomes in PDAC, our review paves the way for future research in this rapidly evolving field.

HDAC inhibitors enhance the anti-tumor effect of immunotherapies in hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the most common liver malignancy with a poor prognosis and increasing incidence, remains a serious health problem worldwide. Immunotherapy has been described as one of the ideal ways to treat HCC and is transforming patient management. However, the occurrence of immunotherapy resistance still prevents some patients from benefiting from current immunotherapies. Recent studies have shown that histone deacetylase inhibitors (HDACis) can enhance the efficacy of immunotherapy in a variety of tumors, including HCC. In this review, we present current knowledge and recent advances in immunotherapy-based and HDACi-based therapies for HCC. We highlight the fundamental dynamics of synergies between immunotherapies and HDACis, further detailing current efforts to translate this knowledge into clinical benefits. In addition, we explored the possibility of nano-based drug delivery system (NDDS) as a novel strategy to enhance HCC treatment.

Recent advances in nanomedicine-based delivery of histone deacetylase inhibitors for cancer therapy

Histone deacetylase inhibitors (HDACi) are cancer therapeutics that operate at the epigenetic level and which have recently gained wide attention. However, the applications of HDACi are generally hindered by their poor physicochemical characteristics and unfavorable pharmacokinetic profile. Inspired by the approved nanomedicine-based drugs in the market, nanocarriers could provide a resort to circumvent the limitations imposed by HDACi. Enhanced tumor targeting, improved cellular uptake and reduced toxicity are major advantages offered by HDACi-loaded nanoparticles. More importantly, site-specific drug delivery can be achieved via engineered stimuli-responsive nanosystems. In this review we elucidate the anticancer mechanisms of HDACi and their structure-activity relationships, with a special focus on their nanomedicine-based delivery, different drug loading concepts and their implications.

Recent advances in co-delivery nanosystems for synergistic action in cancer treatment

Nanocarrier delivery systems have been widely studied to carry unique or dual chemical drugs. The major challenge of chemotherapies is to overcome the multidrug-resistance (MDR) of cells to antineoplastic medicines. In this context, nano-scale technology has allowed researchers to develop biocompatible nano-delivery systems to overcome the limitation of chemical agents. The development of nano-vehicles may also be directed to co-deliver different agents such as drugs and genetic materials. The delivery of nucleic acids targeting specific cells is based on gene therapy principles to replace the defective gene, correct genome errors or knock-down a particular gene. Co-delivery systems are attractive strategies due to the possibility of achieving synergistic therapeutic effects, which are more effective in overcoming the MDR of cancer cells. These combined therapies can provide better outcomes than separate delivery approaches carrying either siRNA, miRNA, pDNA, or drugs. This article reviews the main design features that need to be associated with nano-vehicles to co-deliver drugs, genes, and gene-drug combinations with efficacy. The advantages and disadvantages of co-administration approaches are also overviewed and compared with individual nanocarrier systems. Herein, future trends and perspectives in designing novel nano-scale platforms to co-deliver therapeutic agents are also discussed.

Lipid-Polymer Hybrid Nanoparticle-Based Combination Treatment with Cisplatin and EGFR/HER2 Receptor-Targeting Afatinib to Enhance the Treatment of Nasopharyngeal Carcinoma

Purpose

Nasopharyngeal carcinoma (NPC) is one of the most prevalent carcinomas among the Cantonese population of South China and Southeast Asia (responsible for 8% of all cancers in China alone). Although concurrent platinum-based chemotherapy and radiotherapy have been successful, metastatic NPC remains difficult to treat, and the failure rate is high.

Methods

Thus, we developed stable lipid–polymer hybrid nanoparticles (NPs) containing cisplatin (CDDP) and afatinib (AFT); these drugs act synergistically to counter NPC. The formulated nanoparticles were subjected to detailed in vitro and in vivo analysis.

Results

We found that CDDP and AFT exhibited synergistic anticancer efficacy at a specific molar ratio. NPs were more effective than a free drug cocktail (a combination) in reducing cell viability, enhancing apoptosis, inhibiting cell migration, and blocking cell cycling. Cell viability after CDDP monotherapy was as high as 85.1%, but CDDP+AFT (1/1 w/w) significantly reduced viability to 39.5%. At 1 µg/mL, AFT/CDDP-loaded lipid–polymer hybrid NPs (ACD-LP) were significantly more cytotoxic than the CDDP+AFT cocktail, indicating the superiority of the NP system.

Conclusion

The NPs significantly delayed tumor growth compared with either CDDP or AFT monotherapy and were not obviously toxic. Overall, the results suggest that AFT/CDDP-loaded lipid–polymer hybrid NPs exhibit great potential as a treatment for NPC.

Ligand decorated biodegradable nanomedicine in the treatment of cancer

Cancer is one of the major global health problems, responsible for the second-highest number of deaths. The genetic and epigenetic changes in the oncogenes or tumor suppressor genes alter the regulatory pathways leading to its onset and progression. Conventional methods are used in appropriate combinations for the treatment. Surgery effectively treats localized tumors; however, it fails to treat metastatic tumors, leading to a spread in other organs, causing a high recurrence rate and death. Among the different strategies, the nanocarriers-based approach is highly sought for, but its nonspecific delivery can cause a profound side effect on healthy cells. Targeted nanomedicine has the advantage of targeting cancer cells specifically by interacting with the receptors overexpressed on their surface, overcoming its non-specificity to target healthy cells. Nanocarriers prepared from biodegradable and biocompatible materials are decorated with different ligands by encapsulating therapeutic or diagnostic agents or both to target cancer cells overexpressing the receptors. Scientists are now utilizing a theranostic approach to simultaneously evaluate nanocarrier bio-distribution and its effect on the treatment regime. Herein, we have summarized the recent 5-year efforts in the development of the ligands decorated biodegradable nanocarriers, as a targeted nanomedicine approach, which has been highly promising in the treatment of cancer.

Dual stimuli-responsive polypeptide-calcium phosphate hybrid nanoparticles for co-delivery of multiple drugs in cancer therapy

In this study, a new type of polypeptide, crosslinked methoxy poly(ethylene glycol)-g-poly(aspartic acid)-g-tyrosine (CPPT), was synthesized via a green and simple one-pot polymerization method. With the disulfide-crosslinked interlayer and the CaP shell, the pH and redox dual-sensitive polypeptide-based organic-inorganic hybrid nanoparticles encapsulated curcumin (Cur) into the hydrophobic core of micelles and loaded doxorubicin hydrochloride (DOX) on the hydrophilic segment of micelles as well as CaP shell. The spherical Cur- and DOX-loaded nanoparticles (CPPT@CaP-CD) showed a hydrodynamics size of about 157.9 ± 3.9 nm. The premature leakage of drugs from the nanoparticles at physiological pH was efficiently restrained because of the enhanced structure integrity, whereas at acidic and hypoxia microenvironment the release of both drugs was promoted due to the rapid dissolution of the CaP shell and the break of the disulfide crosslinked network, facilitating the stimuli-responsive controllable drugs release. In vitro anticancer activity evaluation revealed that the co-loaded nanoparticles presented higher cytotoxicity against A549 cells compared with that of the free combination of Cur + DOX. Confocal laser scanning microscopy observation indicated that more DOX and Cur were released into the nucleus triggered by the up-regulated intracellular glutathione (GSH) concentration and decreased pH, displaying enhanced cell uptake. The self-assembling polypeptide-based dual-sensitive drug co-delivery system could be a promising platform for efficient chemotherapy.

Enhanced cellular uptake and cytotoxicity of vorinostat through encapsulation in TPGS-modified liposomes

Vorinostat (VOR) is known as one of the histone deacetylase inhibitors (HDACi) for cancer treatment, and the FDA approves it for cutaneous T cell lymphoma therapy. Poor solubility, permeability, and less anti-cancer activity are the main challenges for the effective delivery of VOR against various cancers. So, our team assumed that the surface-coated liposomes might improve the physicochemical properties of biopharmaceutics classification system class IV drugs such as VOR. The present study aimed to enhance the cytotoxicity and improve cellular uptake using TPGS-coated liposomes in breast cancer cells. Liposomes were fabricated by the film hydration following the probe ultra-sonication method. OR-LIPO and TPGS-VOR-LIPO showed an average particle size of 211.97 ± 3.42 nm with PDI 0.2168 ± 0.006 and 176.99 ± 2.06 nm with PDI 0.175 ± 0.018, respectively. TPGS-coated liposomes had better stability and revealed more than 80 % encapsulation efficiency than conventional liposomes. Transmission electron microscopy confirmed the TPGS coating around liposomes. Moreover, TPGS-coated liposomes enhanced the solubility and showed sustained release of VOR over 48 h. DSC and PXRD analysis also reveal an amorphous state of VOR within the liposomal formulation. MTT assay result indicates that the superior cytotoxic effect of surface-modified liposomes contrasts with the conventional and free VOR solution, respectively. Fluorescence microscopy and flow cytometry results also presented an enhanced cellular uptake of TPGS-coated liposomes against breast cancer cells, respectively. The current investigation's final results declared that TPGS-coated liposomes are promising drug carriers for the effective delivery of hydrophobic drugs for cancer therapy.

Epigenetics in Breast Cancer Therapy-New Strategies and Future Nanomedicine Perspectives

Epigenetic dysregulation has been recognized as a critical factor contributing to the development of resistance against standard chemotherapy and to breast cancer progression via epithelial-to-mesenchymal transition. Although the efficacy of the first-generation epigenetic drugs (epi-drugs) in solid tumor management has been disappointing, there is an increasing body of evidence showing that epigenome modulation, in synergy with other therapeutic approaches, could play an important role in cancer treatment, reversing acquired therapy resistance. However, the epigenetic therapy of solid malignancies is not straightforward. The emergence of nanotechnologies applied to medicine has brought new opportunities to advance the targeted delivery of epi-drugs while improving their stability and solubility, and minimizing off-target effects. Furthermore, the omics technologies, as powerful molecular epidemiology screening tools, enable new diagnostic and prognostic epigenetic biomarker identification, allowing for patient stratification and tailored management. In combination with new-generation epi-drugs, nanomedicine can help to overcome low therapeutic efficacy in treatment-resistant tumors. This review provides an overview of ongoing clinical trials focusing on combination therapies employing epi-drugs for breast cancer treatment and summarizes the latest nano-based targeted delivery approaches for epi-drugs. Moreover, it highlights the current limitations and obstacles associated with applying these experimental strategies in the clinics.

Vorinostat-loaded titanium oxide nanoparticles (anatase) induce G2/M cell cycle arrest in breast cancer cells via PALB2 upregulation

Breast cancer is a group of diseases in which cells divide out of controlled, typically resulting in a mass. Erlotinib is targeted cancer drug which functions as an inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase. It is used mainly to treat of non-small cell lung cancer patients and has an action against pancreatic cancer. Vorinostat (aka suberanilohydroxamic acid) is an inhibitor of histone deacetylases (HDAC), which has an epigenetic modulation activity. It is used to treat cutaneous T cell lymphoma. In the present study, the erlotinib (ERL) and vorinostat (SAHA) loaded TiO₂ nanoparticles (NPs) were used for the treatment of the breast cancer cells (MDA-MB-231 and MCF-7) and human cancerous amniotic cells (WISH). Cell count and viability were negatively affected in all treatments compared to normal cells and bare TiO₂ NPs. Apoptosis results indicated a significant increase in the total apoptosis in all treatments compared with control cells. ERL- and SAHA-loaded TiO₂ NPs treatments arrested breast cancer cells at G2/M phase, which indicate the cytotoxic effect of these treatment. Partner and localizer of BRCA2 (PALB2) gene expression was assessed using qPCR. The results indicate that PLAB2 was upregulated in ERL- and SAHA-loaded TiO₂ NPs compared with control cells and can be used as nanocarrier for chemotherapy drugs. However, this conclusion necessitates further confirmative investigation.

Nanotechnology-Based Histone Deacetylase Inhibitors for Cancer Therapy

Histone deacetylase inhibitors (HDACi) have been approved and achieved success in hematologic malignancies. But its application in solid tumors still confronts big challenges and is hampered by low treatment efficacy. Nanotechnology has been widely applied in cancer therapy, and nanomedicine could improve drug stability, prolong the circulation half-life, and increase intratumoral drug accumulation. Therefore, nanomedicine is a promising strategy to enhance HDACi therapy efficacy. The review provides a summary of the advances of HDACi nanomedicines with a focus on the design principles of the targeting delivery systems for HDACi.

Application of Paclitaxel-loaded EGFR Peptide-conjugated Magnetic Polymeric Liposomes for Liver Cancer Therapy

Developing the methodologies that allow for safe and effective delivery of therapeutic drugs to target sites is a very important research area in cancer therapy. In this study, polyethylene glycol (PEG)-coated magnetic polymeric liposome (MPL) nanoparticles (NPs) assembled from octadecyl quaternized carboxymethyl chitosan (OQC), PEGylated OQC, cholesterol, and magnetic NPs, and functionalized with epithelial growth factor receptor (EGFR) peptide, were successfully prepared for in-vivo liver targeting. The two-step liver targeting strategy, based on both magnetic force and EGFR peptide conjugation, was evaluated in a subcutaneous hepatocellular carcinoma model of nude mouse. The results showed that EGFR-conjugated MPLs not only accumulated in the liver by magnetic force, but could also diffuse into tumor cells as a result of EGFR targeting. In addition, paclitaxel (PTX) was incorporated into small EGFR-conjugated MPLs (102.0±0.7 nm), resulting in spherical particles with high drug encapsulation efficiency (>90%). The use of the magnetic targeting for enhancing the transport of PTX-loaded EGFR-conjugated MPLs to the tumor site was further confirmed by detecting PTX levels. In conclusion, PTX-loaded EGFR-conjugated MPLs could potentially be used as an effective drug delivery system for targeted liver cancer therapy.

Inhalable hybrid nanocarriers for respiratory disorders

Rapid advancements in the field of drug delivery lead to increased use of inhalable formulations as they are cost effective, noninvasive, and targeted and have less systemic side effects and above all better patient compliance. Development of inhalable hybrid systems has offered manifold advantages to this area of drug delivery. Inclusion of polymer and lipid, inorganic and organic substances, and metallic nanoparticles all of them aim to achieve codelivery of drugs which are incompatible in single phase systems. The recent progress in nanotechnology has gained momentum toward delivery of siRNA and miRNA and vaccines to the targeted site. The present work is an attempt to compile all the hybrid and inhalable systems to give readers an overview toward this delivery system as much more work is needed in this field to achieve better resolution of inflammatory disorders.

Transferrin-Conjugated Docetaxel-PLGA Nanoparticles for Tumor Targeting: Influence on MCF-7 Cell Cycle

Targeted drug delivery systems are commonly used to improve the therapeutic index of anti-cancer drugs by increasing their selectivity and reducing systemic distribution and toxicity. Ligand-conjugated nanoparticles (NPs) can be effectively applied for active chemotherapeutic targeting to overexpressed receptors of tumor cells. In this study, transferrin (Tf) was successfully conjugated with poly-l-lactic-co-glycolic acid (PLGA) using ethylene diamine confirmed by NMR, for the loading of docetaxel trihydrate (DCT) into PLGA nanoparticles (NPs). The DCT-loaded Tf-conjugated PLGA NPs were produced by an emulsion-solvent evaporation technique, and a 3² full factorial design was used to optimize the nanoparticle formulations. The DCT-loaded Tf-conjugated PLGA NPs were characterized by FTIR spectroscopy, differential scanning calorimetry, powder X-ray diffraction (PXRD), TEM, particle size, and zeta potential analysis. In vitro release kinetics confirmed that release of DCT from the designed formulations followed a zero-order kinetics and a diffusion controlled non-Fickian release profile. The DCT-loaded Tf-conjugated PLGA NPs were evaluated in vitro in MCF-7 cells for bioactivity assessment. Cytotoxicity studies confirmed that the Tf-conjugated PLGA NPs were more active than the non-conjugated counterparts. Cell uptake studies re-confirmed the ligand-mediated active targeting of the formulated NPs. From the cell cycle analysis, the anti-cancer activity of DCT-loaded Tf-conjugated PLGA NPs was shown to occur by arresting the G₂/M phase.

Approaches to CNS Drug Delivery with a Focus on Transporter-Mediated Transcytosis

Drug delivery to the central nervous system (CNS) conferred by brain barriers is a major obstacle in the development of effective neurotherapeutics. In this review, a classification of current approaches of clinical or investigational importance for the delivery of therapeutics to the CNS is presented. This classification includes the use of formulations administered systemically that can elicit transcytosis-mediated transport by interacting with transporters expressed by transvascular endothelial cells. Neurotherapeutics can also be delivered to the CNS by means of surgical intervention using specialized catheters or implantable reservoirs. Strategies for delivering drugs to the CNS have evolved tremendously during the last two decades, yet, some factors can affect the quality of data generated in preclinical investigation, which can hamper the extension of the applications of these strategies into clinically useful tools. Here, we disclose some of these factors and propose some solutions that may prove valuable at bridging the gap between preclinical findings and clinical trials.

The ROMP: A Powerful Approach to Synthesize Novel pH-Sensitive Nanoparticles for Tumor Therapy

Fast clearance, metabolism, and systemic toxicity are major limits for the clinical use of anti-cancer drugs. Histone deacetylase inhibitors (HDACi) present these defects, despite displaying promising anti-tumor properties on tumor cells in vitro and in in vivo models of cancer. The specific delivery of anti-cancer drugs into the tumor should improve their clinical benefit by limiting systemic toxicity and by increasing the anti-tumor effect. This paper deals with the synthesis of the polymeric nanoparticle platform, which was produced by Ring-Opening Metathesis Polymerization (ROMP), able to release anti-cancer drugs in dispersion, such as histone deacetylase inhibitors, into mesothelioma tumors. The core-shell nanoparticles (NPs) have stealth properties due to their poly(ethylene oxide) shell and can be viewed as universal nano-carriers on which any alkyne-modified anti-cancer molecule can be grafted by click chemistry. A cleavage reaction of the chemical bond between NPs and drugs through the contact of NPs with a medium presenting an acidic pH, which is typically a cancer tumor environment or an acidic intracellular compartment, induces a controlled release of the bioactive molecule in its native form. In our in vivo syngeneic model of mesothelioma, a highly selective accumulation of the particles in the tumor was obtained. The release of the drugs led to an 80% reduction of tumor weight for the best compound without toxicity. Our work demonstrates that the use of theranostic nanovectors leads to an optimized delivery of epigenetic inhibitors in tumors, which improves their anti-tumor properties in vivo.

Transferrin-Conjugated Polymeric Nanoparticle for Receptor-Mediated Delivery of Doxorubicin in Doxorubicin-Resistant Breast Cancer Cells

In this study, a transferrin (Tf)-conjugated polymeric nanoparticle was developed for the targeted delivery of the chemotherapeutic agent doxorubicin (Dox) in order to overcome multi-drug resistance in cancer treatment. Our objective was to improve Dox delivery for producing significant antitumor efficacy in Dox-resistant (R) breast cancer cell lines with minimum toxicity to healthy cells. The results of our experiments revealed that Dox was successfully loaded inside a transferrin (Tf)-conjugated polymeric nanoparticle composed of poloxamer 407 (F127) and 123 (P123) (Dox/F127&P123-Tf), which produced nanosized particles (~90 nm) with a low polydispersity index (~0.23). The accelerated and controlled release profiles of Dox from the nanoparticles were characterized in acidic and physiological pH and Dox/F127&P123-Tf enhanced Dox cytotoxicity in OVCAR-3, MDA-MB-231, and MDA-MB-231(R) cell lines through induction of cellular apoptosis. Moreover, Dox/F127&P123-Tf inhibited cell migration and altered the cell cycle patterns of different cancer cells. In vivo study in MDA-MB-231(R) tumor-bearing mice demonstrated enhanced delivery of nanoparticles to the tumor site when coated in a targeting moiety. Therefore, Dox/F127&P123-Tf has been tailored, using the principles of nanotherapeutics, to overcome drug-resistant chemotherapy.

Transferrin-conjugated pH-sensitive platform for effective delivery of porous palladium nanoparticles and paclitaxel in cancer treatment

Porous palladium (Pd) nanoparticles have garnered great research attention due to their potential anticancer activity and photothermal effect. In this study, a transferrin-conjugated pH-sensitive platform (Tf-PPP), comprising porous Pd nanoparticles (PdNPs) and paclitaxel (PTX), was successfully developed for combined chemo-phototherapy. Tf-PPPs have a small size of 164.6 ± 8.7 nm, PDI of 0.278 ± 0.029, and negative charge (-13.2 ± 1.8 mV). Poly(acrylic acid)-poly(ethylene oxide) (PAA-PEO), a pH sensitive polymer, was used to achieve pH-dependent drug release from nanoparticles. Transferrin (Tf) conjugated on the surface of nanoplatforms could enhance the cellular uptake and prolong nanoparticle accumulation in the tumor site. The combination of phototherapy induced by PdNPs and chemotherapeutic agent (PTX) could exhibit synergistic anticancer activities. Consistent findings were observed in both in vitro experiments including cytotoxicity, live/dead assay, and assessment of apoptotic protein levels, and in vivo antitumor study in MCF-7 tumor-bearing mice, with results decreasing in the following order: Tf-PPPs + NIR > Tf-PPPs > PPPs + NIR > PPPs > PTX > PdNPs. These findings suggest that the administration of Tf-PPPs, followed by NIR irradiation could be a promising strategy in the treatment of cancer.

Hyaluronic acid-capped compact silica-supported mesoporous titania nanoparticles for ligand-directed delivery of doxorubicin

Mesoporous titania nanoparticles (MTN), owing to their high surface area to volume ratio and tunable pore sizes, appear capable of delivering sizable amounts of drug payloads, and hence, show considerable promise as drug delivery candidates in cancer therapy. We designed silica-supported MTN (MTNst) coated with hyaluronic acid (HA) to effectively deliver doxorubicin (DOX) for breast cancer therapy. The HA coating served a dual purpose of stabilizing the payload in the carriers as well as actively targeting the nanodevices to CD44 receptors. The so-formed HA-coated MTNst carrying DOX (HA/DOX-MTNst) had spheroid particles with a considerable drug-loading capacity and showed significantly superior in vitro cytotoxicity against MDA-MB-231 cells as compared to free DOX. HA/DOX-MTNst markedly improved the cellular uptake of DOX in an apparently CD44 receptor-dependent manner, and increased the number of apoptotic cells as compared to free DOX. These nanoplatforms accumulated in large quantities in the tumors of MDA-MB-231 xenograft tumor-bearing mice, where they significantly enhanced the inhibition of tumor growth compared to that observed with free DOX with no signs of acute toxicity. Based on these excellent results, we deduced that HA/DOX-MTNst could be successfully used for targeted breast cancer therapy. STATEMENT OF SIGNIFICANCE: This is the first study to use silica-supported mesoporous titania nanoparticles (MTNst) for doxorubicin (DOX) delivery to treat breast cancer, which exhibited effective and enhanced in vitro and in vivo apoptosis and tumor growth inhibition. Solid silica was used to support the mesoporous TiO₂ resulting in MTNst, which efficiently incorporated a high DOX payload. The hyaluronic acid (HA) coating over the MTNst surface served a dual purpose of first, stabilizing DOX inside the MTNst (capping agent), and second, directing the nanoplatform device to CD44 receptors that are highly expressed in MDA-MB-231 cells (targeting ligand). The NPs exhibited highly efficacious in vitro tumor-cell killing and excellent in vivo tumor regression, highlighting the enormous promise of this system for breast cancer therapy.

Antiproliferative and Apoptosis Triggering Potential of Paclitaxel-Based Targeted-Lipid Nanoparticles with Enhanced Cellular Internalization by Transferrin Receptors-a Study in Leukemia Cells

Leukemia is a typical blood cancer that is characterized by the numerous duplication and proliferation of white blood cells. The main aim of this study was to develop PTX-loaded multifunctional nanoparticles and target to leukemia cells. In this study, transferrin-decorated paclitaxel-loaded lipid nanoparticle (TPLN) was prepared with an aim to increase the chemotherapeutic efficacy in the leukemia cells. Results clearly showed the superior targeting potential of TPLN to the HL-60 cancer cells compared to that of the paclitaxel-loaded nanoparticles (PLN). To be specific, TPLN showed a significantly higher cytotoxic effect in the cancer cells compared to that of the PLN indicating the superior targeting efficiency of the Tf-decorated nanoparticle system. The IC50 value of TPLN was 0.45 μg/ml compared to 2.8 μg/ml for PLN. TPLN induced a most remarkable apoptosis of the cancer cells and much of the cells were distorted with huge presence of the apoptotic body formation. Importantly, TPLN showed a remarkable reduction in the viable cells proportion to ~ 65% with around ~ 30% apoptosis cells (early and late apoptosis). Overall, results clearly showed the targeting potential of ligand-conjugated lipid nanoparticle system to the leukemia cells that might pave the way for the successful cancer treatment.

Development of zoledronic acid functionalized hydroxyapatite loaded polymeric nanoparticles for the treatment of osteoporosis

The present study formulated a hydroxyapatite (HA)-coated lipid nanoparticle loaded with zoledronic acid to treat patients with osteoporosis (OP). HA-coated zoledronic acid loaded lipid bilayer nanoparticles (HZL NPs) were prepared using methods of extrusion and precipitation. Nanosized particles were prepared with the aim of increasing gradual and prolonged drug release and inducing toxicity of osteoblasts. Cellular morphology was investigated by scanning electron microscopy, which revealed clear spherical shaped NPs ~200 nm in size that could treat osteopores in the bone. In addition, a typical biphasic release pattern was observed that could be attributed to the presence of drug on the outer surface as well as on the inner core of the NPs. There was sustained release behavior [38.17±2.12% (pH 7.4) and 64.2±3.75% (pH 5) at 48 h] of the drug that maintained the drug reservoir effect at the bone site. Furthermore, HZL NPs increased the cytotoxicity of HFOb 1.19 cells and increased the proportion of cells in the early (18.1±12.4%), late (28.7±3.7%) and necrotic (67.5±1.2%) phases of apoptosis. Most importantly, HZL in the lipid nanoparticle exhibited a strong affinity towards HA, further enhancing its efficacy in the treatment of OP.

Folate receptor-mediated celastrol and irinotecan combination delivery using liposomes for effective chemotherapy

Drug targeting using functionalized nanoparticles provides a new standard in anticancer therapy. Liposomes, safe and effective drug delivery carriers, can incorporate both hydrophilic and hydrophobic drugs for combination chemotherapy treatment of cancers. The objectives of the current study were to synthesize and test the effectiveness of a nanotechnology-based strategy utilizing folic acid (FA)-conjugated liposomes that incorporate both celastrol (Cs) and irinotecan (Ir) for targeted breast cancer therapy. Our results revealed the successful preparation of Cs and Ir-loaded folate-targeted liposomes (Lipo/Cs/Ir-FA) with a small particle size (∼190 nm) and polydispersity index (∼0.10). The formulation exhibited higher drug release profiles for both Ir and Cs at pH 5.0 compared to those at physiological pH, favoring cancer cell-targeted release. Furthermore, in vitro cell studies showed high uptake and enhanced apoptosis in folate receptor-positive breast cancer cells (MCF-7 and MDA-MB-231), but not in folate receptor-negative lung cancer cells (A549). Moreover, an in vivo study in a mouse tumor model using MDA-MB-231 xenografts supported effective drug delivery behavior of the folate-conjugated liposomes by selective targeting of tumor tissue and minimizing systemic adverse effects. Therefore, our formulation could provide an effective therapy for targeted cancer treatment.

Facile construction of bioreducible crosslinked polypeptide micelles for enhanced cancer combination therapy

In this study, we developed pH and redox-responsive crosslinked polypeptide-based combination micelles for enhanced chemotherapeutic efficacy and minimized side effects. The stability and drug release properties of the polypeptide micelles were efficiency balanced by the corona-crosslinking of the triblock copolymer, poly(ethylene glycol)-b-poly(aspartic acid)-b-poly(tyrosine) (PEG-b-pAsp-b-pTyr) with coordinated redox and pH dual-sensitivity by introducing disulfide crosslinkages. Because of the crosslinking of the middle shell of the triblock polypeptide micelles, their robust structure was maintained in strong destabilization conditions and exhibited excellent stability. GSH concentrations were significantly higher in tumor tissue than in normal tissue, which formed the basis for our design. Drug release was elevated under redox and low acidic conditions. Furthermore, crosslinked micelles showed a superior anticancer effect compared to that of non-crosslinked micelles. Incorporation of docetaxel (DTX) and lonidamine (LND) in crosslinked polypeptide micelles increased the intracellular reactive oxygen species (ROS) level and oxidative stress and caused damage to intracellular components that resulted in greater apoptosis of cancer cells than when DTX or LND was used alone. The combination of DTX and LND in crosslinked micelles exhibited efficacious inhibition of tumor growth with an excellent safety profile compared to that reported for drug cocktail combinations and non-crosslinked micelles. Overall, redox/pH-responsive polypeptide micelles could be an interesting platform for efficient chemotherapy.

STATEMENT OF SIGNIFICANCE

We have synthesized a biodegradable polypeptide block copolymer to construct a facile pH and redox-responsive polymeric micelle asan advanced therapeutic system for cancer therapy. We have designed a corona-crosslinked triblock copolymer (poly (ethylene glycol)-b-poly(aspartic acid)-b-poly(tyrosine) (PEG-b-pAsp-b-pTyr)) micelles co-loaded with docetaxel and lonidamine (cl-M/DL). The corona of triblock polymer was crosslinked to maintain its structural integrity in the physiological environment. The mitochondrial targeting LND is expected to generate ROS, oxidative stress and thereby synergize the chemotherapeutic efficacy of DTX in killing cancer cells. Consistently, cl-M/DL exhibited excellent antitumor efficacy in xenograft tumor model with remarkable tumor regression. Overall, we demonstrated the construction of bioreducible nanosystem for the effective synergistic delivery of DTX/LND in tumor tissues towards cancer treatment.

Styrene maleic acid-encapsulated RL71 micelles suppress tumor growth in a murine xenograft model of triple negative breast cancer

Patients with triple negative breast cancer have a poor prognosis due in part to the lack of targeted therapies. In the search for novel drugs, our laboratory has developed a second-generation curcumin derivative, 3,5-bis(3,4,5-trimethoxybenzylidene)-1-methylpiperidine-4-one (RL71), that exhibits potent in vitro cytotoxicity. To improve the clinical potential of this drug, we have encapsulated it in styrene maleic acid (SMA) micelles. SMA-RL71 showed improved biodistribution, and drug accumulation in the tumor increased 16-fold compared to control. SMA-RL71 (10 mg/kg, intravenously, two times a week for 2 weeks) also significantly suppressed tumor growth compared to control in a xenograft model of triple negative breast cancer. Free RL71 was unable to alter tumor growth. Tumors from SMA-RL71-treated mice showed a decrease in angiogenesis and an increase in apoptosis. The drug treatment also modulated various cell signaling proteins including the epidermal growth factor receptor, with the mechanisms for tumor suppression consistent with previous work with RL71 in vitro. The nanoformulation was also nontoxic as shown by normal levels of plasma markers for liver and kidney injury following weekly administration of SMA-RL71 (10 mg/kg) for 90 days. Thus, we report clinical potential following encapsulation of a novel curcumin derivative, RL71, in SMA micelles.