Mucoadhesive Cationic Polypeptide Nanogel with Enhanced Penetration for Efficient Intravesical Chemotherapy of Bladder Cancer

Synergistically Enhanced Mucoadhesive and Penetrable Polypeptide Nanogel for Efficient Drug Delivery to Orthotopic Bladder Cancer

Intravesical chemotherapy has been recommended after the gold standard of transurethral resection of the bladder tumor to prevent bladder cancer (BC) from local recurrence in the clinic. However, due to rapid urine excretion and barrier protection of the bladder wall, the clinical performances of chemotherapeutic drugs are severely compromised. In the present work, a smart positively charged disulfide-crosslinked nanogel of oligoarginine-poly(ethylene glycol)–poly(L-phenylalanine-co-L-cystine) (R₉-PEG–P(LP-co-LC)) was prepared to prolong the retention period and enhance the penetration capability of chemotherapeutic agent toward the bladder wall. PEG significantly improved the aqueous dispersibility of the 10-hydroxycamptothecin (HCPT)-loaded R₉-PEG–P(LP-co-LC) (i.e., R₉NG/HCPT) and enhanced the mucoadhesive capability by the nonspecific interaction between PEG chain and the bladder mucosa accompanied with the electrostatic interaction between the cationic R₉ and negatively charged bladder mucosa. Besides, R₉, as a cell-penetrating peptide, efficiently penetrated through the cell membrane and delivered carried cargo. The disulfide bond endowed the selective release behavior of HCPT triggered by the intracellular reductive microenvironment. As an advanced chemotherapeutic nanoformulation, the smart R₉NG/HCPT demonstrated superior cytotoxicity against human BC 5637 cells in vitro and remarkably enhanced tumor suppression activity toward orthotopic BC models of mouse and rat in vivo, indicating its great potential in the clinical intravesical BC chemotherapy.

Photoactivated H2 Nanogenerator for Enhanced Chemotherapy of Bladder Cancer

Hydrogen gas can mitigate oxidative stress in many diseases and is regarded to be safe and free of side effects. Inspired by a metalloenzyme in a variety of microorganisms, here, we propose a photoactivated H₂ nanogenerator that comprises a fluorinated chitosan (FCS), a chemotherapeutic drug (gemcitabine, GEM), and a catalyst of H₂ production ([FeFe]TPP) that can form self-assembled [FeFe]TPP/GEM/FCS nanoparticles (NPs). The [FeFe]TPP/GEM/FCS NPs exhibit excellent transmucosal and tumor cell penetration capacities after intravesical instillation into the bladder and can efficiently produce H₂ gas in situ upon 660 nm laser irradiation, which significantly enhances the efficacy of hydrogen chemotherapy of cancer in vitro and in vivo. Moreover, we discover that H₂ gas in hydrogen chemotherapy can inhibit mitochondrial function, hinder ATP synthesis, and cause a reduction of the P-gp efflux pump function, which finally attenuates P-gp protein drug transport capacity in cancer cells. This photoactivated H₂ evolution in situ to improve the therapeutic efficacy of chemotherapy of bladder cancer may present an effective hydrogen chemotherapy strategy for cancer treatment.

Multifunctional nanoparticles as photosensitizer delivery carriers for enhanced photodynamic cancer therapy

Photodynamic therapy (PDT) is an emerging cancer treatment combining light, oxygen, and a photosensitizer (PS) to produce highly cytotoxic reactive oxygen species that cause cancer cell death. However, most PSs are hydrophobic molecules that have poor water solubility and cannot target tumor tissues, causing damage to normal tissues and cells during PDT. Thus, there is a substantial demand for the development of nanocarrier systems to achieve targeted delivery of PSs into tumor tissues and cells. This review summarizes the research progress in PS delivery systems for PDT treatment of tumors and focuses on the recent design and development of multifunctional nanoparticles as PS delivery carriers for enhanced PDT. These multifunctional nanoparticles possess unique properties, including tunable particle size, changeable shape, stimuli-responsive PS activation, controlled PS release, and hierarchical targeting capability. These properties can increase tumor accumulation, penetration, and cellular internalization of nanoparticles to achieve PS activation and/or release in cancer cells for enhanced PDT. Finally, recent developments in multifunctional nanoparticles for tumor-targeted PS delivery and their future prospects in PDT are discussed.

Mucoadhesive nanoparticles based on ROS activated gambogic acid prodrug for safe and efficient intravesical instillation chemotherapy of bladder cancer

Chemotherapy is the standard of care for bladder cancer after transurethral resection of the tumor. However, the rapid excretion of clinically used formulations of anticancer drugs make the common intravesical instillation chemotherapy far from efficient. Therefore, improving the muco-adhesion and penetrability of chemotherapeutic drugs became the key factors in the post-surgery treatment of superficial bladder cancers. Here, a reduction sensitive vehicle was developed to deliver the reactive oxygen species activated prodrug of gambogic acid for treatment of orthotopic bladder cancer. The positively charged chitosan can significantly enhance the adhesion and permeability of prodrug within the bladder wall. Moreover, by utilizing the different glutathione and ROS level between cancer cells and normal cells, the dual responsive nanoparticle can selectively and rapidly deliver drug in bladder cancer cells, and thus can significantly inhibit the proliferation of bladder cancer cells in an orthotopic superficial bladder cancer model without causing damage to normal cells. This work demonstrates that the smart prodrug nanomedicine may act as a promising drug-delivery system for local chemotherapy of bladder cancer with unprecedented clinical benefits.

Advances in Drug Delivery via Biodegradable Ureteral Stent for the Treatment of Upper Tract Urothelial Carcinoma

Drug eluting ureteral stent is an effective means for local drug delivery to the urinary tract. It can potentially solve a variety of upper urinary tract problems, such as stent-related urinary tract infections and discomfort, ureteral stricture, and neoplastic diseases. However, the release of drug elutes on the surface of biostable stents is unsustainable and uncontrollable. With the development of biomaterial science, the emergence of biodegradable ureteral stents (BUSs) provides a new approach for local drug delivery in the urinary tract. The drugs can be continuously released in a controlled manner from a drug-eluting BUS, when the stent degrades. Especially for the delivery of anti-tumor drugs, the stents can obviously improve the therapeutic effectiveness of the drugs by prolonging the contact duration of the drug and tumor cells. In addition, a secondary stent removal procedure can be avoided. The purpose of this review article is to provide an overview of anti-tumor drug-eluting BUSs and discuss the biomaterials and drug delivery systems of BUS that are currently being developed to deliver anti-tumor drugs for upper tract urothelial carcinoma.

Preparation and Characterization of Chitosan Nanoparticles for Chemotherapy of Melanoma Through Enhancing Tumor Penetration

The poor solubility and permeability of most chemotherapeutic drugs lead to unsatisfactory bioavailability combined with insufficient drug concentration. In this study, positively charged nanoparticles based on chitosan were developed and synthesized to enhance tumor penetration capability of 10-Hydroxycamptothecin (HCPT) in order to improve the chemotherapeutic effect of melanoma. The HCPT encapsulated nanoparticles were noted as NPs/HCPT. NPs/HCPT was characterized by dynamic light scattering and zeta potential measurements. In addition, cell uptake, in vitro cytotoxicity, apoptosis and in vivo antitumor activity of NPs/HCPT were further investigated. The average diameter of NPs/HCPT was approximately 114.6 ± 4.1 nm. The viability of murine melanoma cell lines (B16F10 and B16F1) was significantly decreased due to interaction with NPs/HCPT. Moreover, NPs/HCPT significantly inhibited the progression of tumors. These investigations implied that cationic NPs/HCPT could be potentially applied as a promising drug delivery nanosystem.

Sequential Intra-Intercellular Delivery of Nanomedicine for Deep Drug-Resistant Solid Tumor Penetration

Cells in the center of solid tumors have always been an abyss untouched by treatments because of their deep location and increased drug resistance. Herein, we designed a rational strategy for sequential intra-intercellular delivery of nanomedicine to deep sites of drug-resistant solid tumors. In our formulation, dopamine and hemoglobin were polymerized to form a smart nanocarrier (PDA/Hb). Subsequently, the doxorubicin and nitric oxide donor were connected on the surface of PDA/Hb to obtain D/N-PDA/Hb. Ultimately, the hyaluronic acid was combined with D/N-PDA/Hb to form D/N-PDA/Hb@HA. Concretely, acidic and neutral environments of tumor cells were treated as a switch to turn on or off the drug release of a nanodrug. Meanwhile, the generation of nitric oxide in situ was exploited to favor the lysosomal escape of nanocarriers and overcome the drug resistance of deep solid tumor cells. The results indicated that the nanodrug based on sequential intra-intercellular delivery showed exciting penetration efficiency and resistance reversal of solid tumors. Conventional nanodrug delivery was highly dependent on the enhanced permeability and retention (EPR) effect and limited by tumorous interstitial fluid pressure. Plenty of drugs stayed on the surface of solid tumors, and the infiltrated drugs were inefficient due to strict resistance. To conquer this dilemma, this work proposed a new mechanism reversing the EPR effect for drug delivery, leading to better penetration and resistance reversal of solid tumors.

Cell Membrane-Camouflaged Nanocarriers for Cancer Diagnostic and Therapeutic

Cell membrane (CM)-camouflaged nanocarriers (CMNPs) are the tools of a biomimetic strategy that has attracted significant attention. With a wide range of nanoparticle cores and CMs available, various creative CMNP designs have been studied for cancer diagnosis and therapy. The various functional CM molecules available allow CMNPs to demonstrate excellent properties such as prolonged circulation time, immune escape ability, reduced systemic toxicity, and homologous targeting ability when camouflaged with CMs derived from various types of natural cells including red and white blood cells, platelets, stem cells, and cancer cells. In this review, we summarize various CMNPs employed for cancer chemotherapy, immunotherapy, phototherapy, and in vivo imaging. We also predict future challenges and opportunities for fundamental and clinical studies.

Polymer Nanoformulation of Sorafenib and All-Trans Retinoic Acid for Synergistic Inhibition of Thyroid Cancer

Part of differentiated thyroid cancer will relapse or develop into dedifferentiated thyroid cancer after standard therapy, such as surgery or radionuclide therapy. Sorafenib (SOR) is recommended for the treatment of advanced or radioiodine-refractory thyroid cancer. The monotherapy using SOR is often hampered by its modest efficacy, serve systemic toxicity, and high occurrence of drug resistance. In order to enhance the antitumor effect of SOR and reduce its side effects, SOR and all-trans retinoic acid (ATRA), a differentiation-promoting drug, were loaded into poly(ethylene glycol)-poly(lactide-co-glycolide) (PEG-PLGA) polymer micelles in this study. The drug-loaded micelles, PM/(SOR+ATRA), exhibited relatively slow drug release and effective cell uptake. Compared with other treatment groups, the PM/(SOR+ATRA) treatment group showed the most significant antitumor effect and minimal systemic toxicity toward the FTC-133 thyroid cancer-bearing BALB/c nude mouse model. Immunofluorescence analysis confirmed that PM/(SOR+ATRA) could significantly promote apoptosis and re-differentiation of tumor cells. All the results demonstrated that polymer micelles loaded with SOR and ATRA could treat thyroid cancer more effectively and safely.

Poly(amidoamine)-modified mesoporous silica nanoparticles as a mucoadhesive drug delivery system for potential bladder cancer therapy

Bladder cancer, with the highest recurrence rate in all malignancy, is a common urologic cancer that arises on the bladder mucosa. Currently, tumor resection followed by intravesical chemotherapy is the primary treatment of bladder cancer, which has limited effectiveness ascribe to short dwell-time of intravesical drugs in bladder. Therefore, there is a need to develop mucoadhesive and sustained drug delivery systems to increase drug residence time for intravesical chemotherapy. In this study, poly(amidoamine) (PAMAM) dendrimers were modified onto the surface of mesoporous silica nanoparticles (MSNPs) through a layer-by-layer grafting method. A series of PAMAM-modified MSNPs were prepared and compared for their mucoadhesive capabilities on pig bladder wall and controlled drug release properties. Results demonstrated an increase in the mucoadhesive capacity of PAMAM-modified MSNPs upon an increase in the number of PAMAM amino groups, and the maximum nanoparticle mucoadhesivity was observed after two-generation PAMAM were grafted on the surface of MSNPs. An antineoplastic, doxorubicin, was encapsulated in the mesopores of PAMAM-modified MSNPs, and the drug-loaded nanoparticles can provide a sustained drug release triggered by acidic pH. The present study demonstrates that the mucoadhesive and drug release properties of MSNPs can be controlled by the layer number of PAMAM dendrimers on the nanoparticle surface, holding significant potential for the development of mucoadhesive drug delivery systems for bladder cancer therapy.

Altered Frequency of NK Cells and Treg Cells by Astragalus Polysaccharide Combined with Budesonide in Asthma Model Mice

Objective. We investigated the efficacy of astragalus polysaccharide (APS) combined with budesonide and the effect on expressions of peripheral NK cells and Treg cells and the molecular mechanism in mice with bronchial asthma. Methods. In this study, we established a mouse model of asthma. Four groups of BaLB/C mice were developed; control group had no asthma induction, and the other three groups of mice were sensitized by OVA (Ovalbumin), OVA + budesonide, and OVA + APS + budesonide. Flow cytometry was used to determine the proportion of NK cells and Treg cells. Levels of cytokines IL-4 and IL-10 were detected using RT-PCR and ELISA. Results. Asthma mice treated with APS + budesonide showed alleviated airway resistance compared to model mice (P<0.05). The percentage of dendritic cells (DCs) was reduced (P<0.05), while anti-inflammatory NK cells and Treg cells significantly increased after APS + budesonide treatment (P<0.05). Further, APS + budesonide treatment resulted in improvements in IL-4 and IL-10 mRNA and protein levels (P<0.05). Conclusion. APS combined with budesonide medication may regulate expressions of DCs cells and related cytokines, reliving clinical symptom of bronchial asthma.

Poly(Ethylene Glycol) Crosslinked Multi-Armed Poly(l-Lysine) with Encapsulating Capacity and Antimicrobial Activity for the Potential Treatment of Infection-Involved Multifactorial Diseases

With the development of modern medical technology, common diseases usually can be treated by traditional medicines and their formulation, while diseases with multiple etiologies still remain a great challenge in clinic. Nanoformulation was widely explored to address this problem. However, due to limited drug loading space of nanocarriers, co-delivery strategy usually fails to achieve sufficient loading of multiple drugs simultaneously. In this research, we explored the potential of poly(ethylene glycol) (PEG) crosslinked alternating copolymers MPLL-alt-PEG as both an anionic drug carrier and antimicrobial agent. The high cationic charge density of multi-armed poly(l-lysine) (MPLL) segments in MPLL-alt-PEG could endow the electrostatic encapsulation of anionic model drugs through the formation of polyion complex micelles with a MPLL/drug complex core and crosslinked PEG outer shell, enabling pH-sensitive drug release. Meanwhile, the MPLL-alt-PEG copolymer exhibits a broad spectrum of antimicrobial activities against various clinically relevant microorganisms with low hemolytic activity. Studies on antibacterial mechanism revealed that MPLL-alt-PEG attacked bacteria through the membrane disruption mechanism which is similar to that of typical antimicrobial peptides. Taken together, the present study shed light on the possibility of endowing a polymeric carrier with therapeutic effect and thus offered a promising strategy for achieving a comprehensive treatment of bacterial infection-involved multifactorial diseases.

Targeted multifunctional nanomaterials with MRI, chemotherapy and photothermal therapy for the diagnosis and treatment of bladder cancer

Folate-modified vincristine-loaded polydopamine-coated Fe₃O₄ superparticles are designed as multifunctional nanomaterials for the imaging and treatment of bladder cancer.

Enhanced cellular uptake and nuclear accumulation of drug-peptide nanomedicines prepared by enzyme-instructed self-assembly

Subcellular delivery of nanomedicines has emerged as a promising approach to enhance the therapeutic efficacy of anticancer drugs. Nuclear accumulation of anticancer drugs are essential for its therapeutic efficacy because their targets are generally located within the nucleus. However, strategies for the nuclear accumulation of nanomedicines with anticancer drugs rarely reported. In this study, we reported a promising nanomedicine, comprising a drug-peptide amphiphile, with enhanced cellular uptake and nuclear accumulation capability for cancer therapy. The drug-peptide amphiphile consisted of the peptide ligand PMI (TSFAEYWNLLSP), which was capable of activating the p53 gene by binding with the MDM2 and MDMX located in the cell nucleus. Peptide conformations could be finely tuned by using different strategies including heating-cooling and enzyme-instructed self-assembly (EISA) to trigger molecular self-assembly at different temperatures. Due to the different peptide conformations, the drug-peptide amphiphile self-assembled into nanomedicines with various properties, including stabilities, cellular uptake, and nuclear accumulation. The optimized nanomedicine formed by EISA strategy at a low temperature of 4 °C showed enhanced cellular uptake and nuclear accumulation capability, and thus exhibited superior anticancer ability both in vitro and in vivo. Overall, our study provides a useful strategy for finely tuning the properties and activities of peptide-based supramolecular nanomaterials, which may lead to optimized nanomedicines with enhanced performance.

Updates on intravesical therapy

PURPOSE OF REVIEW

To review the current literature concerning the intravesical treatment of nonmuscle invasive bladder cancer.

RECENT FINDINGS

Bladder cancer is a high prevalent disease. Despite the recognized efficacy of traditional intravesical therapies, the best treatment strategy still needs to be found. Improvement in bladder cancer research lead to develop new intravesical agents and drug delivery systems for nonmuscle invasive bladder cancer tumours. Moreover, the emerging knowledge of bladder cancer immune profile strongly improves and provides new available treatment strategies.

SUMMARY

The future of nonmuscle invasive bladder cancer therapy will be influenced by the development of immunotherapy and new technologies for device-assisted treatment. Moreover, nanotechnology and delivery systems present promising results.

Smart pH-Sensitive Nanogels for Enhancing Synergistic Anticancer Effects of Integrin αvβ3 Specific Apoptotic Peptide and Therapeutic Nitric Oxide

Apoptotic peptide (kla), which can trigger the mitochondria-mediated apoptotic programmed cell death, has been widely recognized as a potential anticancer agent. However, its therapeutic potential has been significantly impaired by its poor biostability, lack of tumor specificity, and particularly low cellular uptake. Herein, a linear peptide Arg-Trp-d-Arg-Asn-Arg (RWrNR) was identified as an integrin α_vβ₃ specific ligand with a nanomolar dissociation constant (K_d = 0.95 nM), which can greatly improve kla antitumor activity (IC₅₀ = 8.81 μM) by improving its cellular uptake, compared to the classic integrin-recognition motif c-RGDyK (IC₅₀ = 37.96 μM). Particularly, the RWrNR-kla conjugate can be entrapped in acidic sensitive nanogels (RK/Parg/CMCS-NGs), composed of poly-l-arginine (Parg) and carboxymethyl chitosan (CMCS, pI = 6.8), which can not only carry out controlled release of RWrNR-kla in response to the tumor acidic microenvironment, and consequently enhance its tumor specificity and cell internalization, but also trigger tumor-associated macrophages to generate nitric oxide, leading to enhanced synergistic anticancer efficacy. Importantly, RK/Parg/CMCS-NGs have been proven to effectively activate the apoptosis signaling pathway in vivo and significantly inhibit tumor growth with minimal adverse effects. To summarize, RK/Parg/CMCS-NGs are a promising apoptotic peptide-based therapeutics with enhanced tumor accumulation, cytosolic delivery, and synergistic anticancer effects, thereby holding great potential for the treatment of malignant tumors.

Immunomodulatory Nanosystems

Immunotherapy has emerged as an effective strategy for the prevention and treatment of a variety of diseases, including cancer, infectious diseases, inflammatory diseases, and autoimmune diseases. Immunomodulatory nanosystems can readily improve the therapeutic effects and simultaneously overcome many obstacles facing the treatment method, such as inadequate immune stimulation, off-target side effects, and bioactivity loss of immune agents during circulation. In recent years, researchers have continuously developed nanomaterials with new structures, properties, and functions. This Review provides the most recent advances of nanotechnology for immunostimulation and immunosuppression. In cancer immunotherapy, nanosystems play an essential role in immune cell activation and tumor microenvironment modulation, as well as combination with other antitumor approaches. In infectious diseases, many encouraging outcomes from using nanomaterial vaccines against viral and bacterial infections have been reported. In addition, nanoparticles also potentiate the effects of immunosuppressive immune cells for the treatment of inflammatory and autoimmune diseases. Finally, the challenges and prospects of applying nanotechnology to modulate immunotherapy are discussed.

Hydroxycamptothecin Inhibits Peritendinous Adhesion via the Endoplasmic Reticulum Stress-Dependent Apoptosis

Traumatic peritendinous fibrosis is a worldwide clinical problem resulting in severe limb disability. Hydroxycamptothecin (HCPT) is an anti-neoplastic drug widely exploited in clinical practice. It has shown potential of anti-fibrosis in recent years. We previously demonstrated that HCPT inhibited the characterization of fibrosis in vitro. However, it is still unclear whether it ameliorates peritendinous adhesion in an in vivo animal tendon injury model. The underlying mechanism is also worth investigating. The present study aims to determine whether HCPT inhibits tendon adhesion and to explore the underlying mechanisms. In a rat tendon injury model, we observed that topical application of HCPT significantly attenuated peritendinous adhesion as revealed by the results of macroscopic observation, biomechanical, histological, immunohistochemical evaluation, western blot, and quantitative PCR (q-PCR) analyses. Furthermore, western blot and q-PCR analyses revealed that this phenomenon is correlated with HCPT activation of endoplasmic reticulum (ER) stress. In addition, in vitro studies show that HCPT significantly inhibits fibroblast proliferation and induces apoptosis by reducing the expression of extracellular matrix (ECM) proteins COL3A1 and α-smooth muscle actin (α-SMA). Finally, we employed small interfering RNA (siRNA) to target inositol requiring kinase 1 (IRE1) and activated transcription factor 6 (ATF-6) to verify that the effect of inhibitory fibrosis of HCPT disappears after knockdown of ATF-6 and IRE1, thereby suggesting that an anti-fibrotic effect of HCPT is mediated by the ER-dependent apoptotic pathway. In conclusion, our results indicate that HCPT inhibits peritendinous fibrosis through the ER-dependent apoptotic pathway and might serve as a potential solution to prevent traumatic peritendinous adhesion.

Carbon Dots for In Vivo Bioimaging and Theranostics

Carbon dots (CDs), a kind of carbon material discovered accidentally, exhibit unexpected advantages in fluorescence imaging/sensing such as photostability, biocompatibility, and low toxicity. For emerging theranostics, an interdiscipline created by integrating therapy and diagnostics, CDs are good candidates when they are combined with targeted chemo/gene/photodynamic/photothermal therapeutic moieties. Here, the development of CDs in nanomedicine is reviewed from their use as original imaging agents and/or drug carriers to multifunctional theranostic systems. Finally, the challenges and prospects of the next-generation of CD-based theranostics for clinical applications are also discussed.

Nanoparticles Containing Hyaluronan Acid and Astragalus Polysaccharides for Treating Osteoarthritis

The pathogeny of osteoarthritis (OA) is very complicated and still is one of the difficulties in a treating procedure. Here, we constructed nanoparticles using hyaluronan acid (HA) and astragalus polysaccharides (APS) for OA therapy. We assessed OA biomarkers and IL-1β-induced matrix metalloproteinase (MMP) expressions. Nanoparticles of 100 nm showed high drug loading of 28.6% (w/w) and extended drug release of 59% over 1 month. Our results demonstrated that nano treatment significantly improved IL-1β-induced cell viability of chondrocytes. Induction of MMP-9, MMP-13, and TNF-α was alleviated by nanoparticles. Furthermore, nano elevated the expression of osteopontin (OPN) and attenuated inducible nitric oxide synthase (iNOS) protein. Our data indicated the protective role of HA and APS-capsuled nanoparticles in OA treatment.

Recent Advances in Degradable Hybrids of Biomolecules and NGs for Targeted Delivery

Recently, the fast development of hybrid nanogels dedicated to various applications has been seen. In this context, nanogels incorporating biomolecules into their nanonetworks are promising innovative carriers that gain great potential in biomedical applications. Hybrid nanogels containing various types of biomolecules are exclusively designed for: improved and controlled release of drugs, targeted delivery, improvement of biocompatibility, and overcoming of immunological response and cell self-defense. This review provides recent advances in this rapidly developing field and concentrates on: (1) the key physical consequences of using hybrid nanogels and introduction of biomolecules; (2) the construction and functionalization of degradable hybrid nanogels; (3) the advantages of hybrid nanogels in controlled and targeted delivery; and (4) the analysis of the specificity of drug release mechanisms in hybrid nanogels. The limitations and future directions of hybrid nanogels in targeted specific- and real-time delivery are also discussed.

Chitosan-Based Nanogel Enhances Chemotherapeutic Efficacy of 10-Hydroxycamptothecin against Human Breast Cancer Cells

Chitosan (CS), the second most abundant polysaccharide in nature, has been widely developed as a nanoscopic drug delivery vehicle due to its intriguing characteristics. In this work, a positively charged CS-based nanogel was designed and synthesized to inhibit the proliferation of breast cancer cell lines. The model drug of 10-hydroxycamptothecin (HCPT) was entrapped into the core via a facile diffusion to form CS/HCPT. The characteristics of CS/HCPT were evaluated by assessing particle size, drug loading content, and drug loading efficiency. Furthermore, cell internalization, cytotoxicity, and apoptosis of CS/HCPT were also investigated in vitro. The present investigation indicated that the positively charged CS-based nanogel could be potentially used as a promising drug delivery system.

pH-Responsive Dual Drug-Loaded Nanocarriers Based on Poly (2-Ethyl-2-Oxazoline) Modified Black Phosphorus Nanosheets for Cancer Chemo/Photothermal Therapy

Synergistic cancer therapy, such as those combining chemotherapeutic and photothermal methods, has stronger treatment effect than that of individual ones. However, it is challenging to efficiently deliver nanocarriers into tumor cells to elevate intracellular drug concentration. Herein, we developed an effective pH-responsive and dual drug co-delivery platform for combined chemo/photothermal therapy. An anticancer drug doxorubicin (DOX) was first loaded onto the surface of black phosphorus (BP). With poly(2-ethyl-2-oxazoline) (PEOz) ligand conjugated onto the polydopamine (PDA) coated BP nanosheets, targeted long circulation and cellular uptake in vivo was significantly improved. With another anticancer drug bortezomib (BTZ) loaded onto the surface of the nanocapsule, the platform can co-deliver two different drugs. The surface charge of the nanocapsule was reversed from negative to positive at the tumor extracellular pH (∼6.8), ionizing the tertiary amide groups along the PEOz chain, thus facilitating the cell internalization of the nanocarrier. The cytotoxicity therapeutic effect of this nanoplatform was further augmented under near-infrared laser irradiation. As such, our DOX-loaded BP@PDA-PEOz-BTZ platform is very promising to synergistic cancer therapy.

Polypeptide Nanogels With Different Functional Cores Promote Chemotherapy of Lung Carcinoma

Two kinds of tumor microenvironment-responsive polypeptide nanogels were developed for intracellular delivery of cytotoxics to enhance the antitumor efficacies and reduce the side effects in the chemotherapy of lung carcinoma. The sizes of both doxorubicin (DOX)-loaded nanogels methoxy poly(ethylene glycol)-poly(L-phenylalanine-co-L-cystine) [mPEG-P(LP-co-LC)] and methoxy poly(ethylene glycol)-poly(L-glutamic acid-co-L-cystine) [mPEG-P(LG-co-LC)] (NGP/DOX and NGG/DOX) were less than 100 nm, which was appropriate for the enhanced permeability and retention (EPR) effect. The bigger and smaller scale of nanoparticle could induce the elimination of reticuloendothelial system (RES) and decrease the in vivo circulating half-life, respectively. The loading nanogels were stable in the neutral environment while quickly degraded in the mimic intracellular microenvironment. Furthermore, the DOX-loaded reduction-responsive nanogels showed significantly higher tumor cell uptake than free DOX⋅HCl as time went on from 2 to 6 h. In addition, these DOX-loaded nanogels showed efficient antitumor effects in vivo, which was verified by the obviously increased necrosis areas in the tumor tissues. Furthermore, these DOX-loaded nanogels efficiently reduced the side effects of DOX. In conclusion, these reduction-responsive polypeptides based nanogels are suitable for the efficient therapy of lung carcinoma.

Gradiently degraded electrospun polyester scaffolds with cytostatic for urothelial carcinoma therapy

Gradiently degraded cytostatic-loaded electrospun polyester scaffolds as potential self-removing ureteral stents prevent the recurrence of urothelial carcinoma.

A Tf-modified tripterine-loaded coix seed oil microemulsion enhances anti-cervical cancer treatment

Purpose

A transferrin-modified microemulsion carrying coix seed oil and tripterine (Tf-CT-MEs) was developed for improved tumor-specific accumulation and penetration to enhance cervical cancer treatment.

Materials and methods

Tripterine-loaded coix seed oil microemulsion (CT-MEs) was prepared through one-step emulsion method. The morphology, size, and zeta potential of CT-MEs and Tf-CT-MEs were examined by transmission electron microscopy and dynamic light scattering. The cellular uptake and mechanisms of HeLa cells were investigated by flow cytometry. Intratumor penetration was investigated using a HeLa three-dimensional (3D) tumor spheroid as the model. The cytotoxicity of the CT-MEs and Tf-CT-MEs against HeLa cells were evaluated by the MTT assay. Additionally, the apoptotic rate of CT-MEs and Tf-CT-MEs inducing apoptosis in HeLa cells was evaluated.

Results

In the physicochemical characterization, coix seed oil and CT-MEs exhibited a small size (32.47±0.15 nm) and nearly neutral surface charge (−0.36±0.11 mV). After modification with transferrin, the particle size of Tf-CT-MEs slightly increased to 40.02±0.21 nm, but the zeta potential decreased remarkably to -13.63±1.31 mV. The IC₅₀ of Tf-CT-MEs against HeLa cells was 0.7260 µM, which was 2.58-fold lower than that of CT-MEs. In cellular studies, the intracellular fluorescence intensity of fluorescein isothiocyanate (FITC)-labeled Tf-CT-MEs (FITC/Tf-CT-MEs) was 2.28-fold higher than that of FITC-labeled CT-MEs (FITC/CT-MEs). The fluorescence signal of Tf-CT-MEs was observed at 350 µm below the surface of the 3D tumor spheroid. The apoptotic rate of cells treated with Tf-CT-MEs was 1.73- and 2.77-fold higher than that of cells treated with CT-MEs and tripterine, respectively, which was associated with mitochondrial-targeted delivery of tripterine. Moreover, Tf-CT-MEs was capable of significantly downregulating the cellular level of antiapoptotic proteins and arrested cell proliferation in the G₂/M phase.

Conclusion

Taken together, Tf-CT-MEs holds promising potential to be an efficient drug delivery system for combinational therapy of cervical cancer.

Lactoferrin-conjugated pH and redox-sensitive polymersomes based on PEG-S-S-PLA-PCL-OH boost delivery of bacosides to the brain

In the present study, engineered lactoferrin (Lf)-conjugated pH and redox-sensitive polymersomes derived from the triblock copolymer polyethylene glycol-S-S-polylactic acid-polycaprolactone (PEG-S-S-PLA-PCL-OH) have been used to deliver bacosides to the brain. Bacosides are classified as triterpenoid saponins and are used in Indian Ayurveda for reversal of amnesia; however, no study has extensively demonstrated their efficacy as a nano-formulation in an animal model. The polymer was synthesized by ring opening polymerization of lactide and ε-caprolactone. The nanoparticles obtained by nanoprecipitation showed a core-shell morphology, with an average size of 110 nm, by transmission electron microscopy (TEM). The colloidal stability, hemocompatibility and cytocompatibility of the polymersomes proved their biocompatibility. pH and disulfide linkages in the polymeric chain accelerated the disintegration of the polymersomes at pH 6.6 and at pH 6.6 with glutathione (GSH) in comparison to pH 7.4, supporting their degradation behavior. Supermagnetic iron oxide nanoparticles (SPIONs, 74.99 μg mg-1 polymer) encapsulated into the polymersomes demonstrated their uptake in a mouse model by MRI. Furthermore, bacosides encapsulated in the polymersomes (10% loading) showed significant memory loss reversal in chemically induced amnesic mice, supported by the gene expression profiles of Arc, BDNF and CREB as well as by histopathology.

A biodegradable polyphosphoester-functionalized poly(disulfide) nanocarrier for reduction-triggered intracellular drug delivery

Stimuli-responsive and biodegradable polymeric carriers are of great importance for safe delivery and efficient release of chemotherapeutic agents. In this work, given the unique advantages of poly(disulfide)s and biodegradable polyphosphoesters, we designed and constructed a reduction-sensitive amphiphilic triblock copolymer poly(ethyl ethylene phosphate)-b-poly(disulfide)-b-poly(ethyl ethylene phosphate) (PEEP-PDS-PEEP) by combining thiol-disulfide polycondensation and ring-opening polymerization (ROP). The thiol-disulfide polycondensation between 1,6-hexanedithiol and 2,2'-dithiodipyridine yielded the linear telechelic pyridyl disulfide-terminated poly(disulfide)s, followed by the treatment with 2-mercaptoethanol to quantitatively produce dihydroxyl-terminated poly(disulfide)s, which was used to initiate the ROP reaction of 2-ethoxy-2-oxo-1,3,2-dioxaphospholane, generating ABA-type amphiphilic triblock copolymers. The chemical structures of various polymers were thoroughly characterized and verified using nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, gel permeation chromatography (GPC) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectroscopy. The resultant amphiphilic PEEP-PDS-PEEP could self-assemble into spherical nanoparticles in aqueous solution as evidenced from dynamic light scattering (DLS) and transmission electron microscopy (TEM) analyses. Hydrophobic anti-tumor drug doxorubicin (DOX) was used to study the encapsulation capacity of nanoparticles, the drug loading content (DLC) and drug loading efficiency (DLE) values were determined to be 11.2% and 31.5%, respectively. In vitro release studies indicated that DOX was released much faster under reductive conditions compared to physiological conditions, confirming their reduction-responsive release behavior owing to the scission of the poly(disulfide) segment and subsequent disintegration of nanoparticles. The cellular uptake study using a live cell imaging system demonstrated that this DOX-loaded nanoparticle can be internalized into HeLa cells and release DOX over time. Methyl thiazolyl tetrazolium (MTT) assay revealed the favorable cytocompatibility of a bare triblock copolymer toward both L929 and HeLa cells, whereas the DOX-loaded copolymer nanoparticles exhibited the lower inhibitory ability against HeLa and HepG2 cell proliferation than free DOX. This finding presents a strategy for the construction of biocompatible and reduction-responsive polymeric drug carriers.