Monocyte metabolic reprogramming promotes pro-inflammatory activity and Staphylococcus aureus biofilm clearance.

Biofilm-associated prosthetic joint infections (PJIs) cause significant morbidity due to their recalcitrance to immune-mediated clearance and antibiotics, with Staphylococcus aureus (S. aureus) among the most prevalent pathogens. We previously demonstrated that S. aureus biofilm-associated monocytes are polarized to an anti-inflammatory phenotype and the adoptive transfer of pro-inflammatory macrophages attenuated biofilm burden, highlighting the critical role of monocyte/macrophage inflammatory status in dictating biofilm persistence. The inflammatory properties of leukocytes are linked to their metabolic state, and here we demonstrate that biofilm-associated monocytes exhibit a metabolic bias favoring oxidative phosphorylation (OxPhos) and less aerobic glycolysis to facilitate their anti-inflammatory activity and biofilm persistence. To shift monocyte metabolism in vivo and reprogram cells to a pro-inflammatory state, a nanoparticle approach was utilized to deliver the OxPhos inhibitor oligomycin to monocytes. Using a mouse model of S. aureus PJI, oligomycin nanoparticles were preferentially internalized by monocytes, which significantly reduced S. aureus biofilm burden by altering metabolism and promoting the pro-inflammatory properties of infiltrating monocytes as revealed by metabolomics and RT-qPCR, respectively. Injection of oligomycin alone had no effect on monocyte metabolism or biofilm burden, establishing that intracellular delivery of oligomycin is required to reprogram monocyte metabolic activity and that oligomycin lacks antibacterial activity against S. aureus biofilms. Remarkably, monocyte metabolic reprogramming with oligomycin nanoparticles was effective at clearing established biofilms in combination with systemic antibiotics. These findings suggest that metabolic reprogramming of biofilm-associated monocytes may represent a novel therapeutic approach for PJI.

Head-to-head comparative pharmacokinetic and biodistribution (PK/BD) study of two dexamethasone prodrug nanomedicines on lupus-prone NZB/WF1 mice.

HPMA copolymer-based dexamethasone prodrug (P-Dex) and PEG-based dexamethasone prodrug (PEG-Dex, ZSJ-0228) were previously found to passively target the inflamed kidney and provide potent and sustained resolution of nephritis in NZB/WF1 lupus-prone mice. While both prodrug nanomedicines effectively ameliorate lupus nephritis, they have demonstrated distinctively different safety profiles. To explore the underlining mechanisms of these differences, we conducted a head-to-head comparative PK/BD study of P-Dex and PEG-Dex on NZB/WF1 mice. Overall, the systemic organ/tissue exposures to P-Dex and Dex released from P-Dex were found to be significantly higher than those of PEG-Dex. The high prodrug concentrations were sustained in kidney for only 24 h, which cannot explain their lasting therapeutic efficacy (>1 month). P-Dex showed sustained presence in liver, spleen and adrenal gland, while the presence of PEG-Dex in these organs was transient. This difference in PK/BD profiles may explain PEG-Dex' superior safety than P-Dex.

Combination Therapies and Drug Delivery Platforms in Combating Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC), the fourth leading cause of cancer-related death in the United States, is highly aggressive and resistant to both chemo- and radiotherapy. It remains one of the most difficult-to-treat cancers, not only due to its unique pathobiological features such as stroma-rich desmoplastic tumors surrounded by hypovascular and hypoperfused vessels limiting the transport of therapeutic agents, but also due to problematic early detection, which renders most treatment options largely ineffective, resulting in extensive metastasis. To elevate therapeutic effectiveness of treatments and overt their toxicity, significant enthusiasm was generated to exploit new strategies for combating PDAC. Combination therapy targeting different barriers to mitigate delivery issues and reduce tumor recurrence and metastasis has demonstrated optimal outcomes in patients' survival and quality of life, providing possible approaches to overcome therapeutic challenges. This paper aims to provide an overview of currently explored multimodal therapies using either conventional therapy or nanomedicines along with rationale, up-to-date progress, as well as the key challenges that must be overcome. Understanding the future directions of the field may assist in the successful development of novel treatment strategies for enhancing therapeutic efficacy in PDAC.

A Polymeric Nanogel-Based Treatment Regimen for Enhanced Efficacy and Sequential Administration of Synergistic Drug Combination in Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers. A combination of cisplatin (CDDP) and gemcitabine (Gem) treatment has shown favorable clinical results for metastatic disease; both are limited by toxicities and nontargeted delivery. More than 80% of PDAC aberrantly expresses the sialyl Tn (STn) antigen due to the loss of function of the core 1ß3-Gal-T-specific molecular chaperone, a specific chaperone for the activity of core 1 ß3-galactosyltransferase or C1GalT. Here, we report the development of polymeric nanogels (NGs) loaded with CDDP and coated with an anti-STn antigen-specific antibody (TKH2 monoclonal antibody) for the targeted treatment of PDAC. TKH2-functionalized, CDDP-loaded NGs delivered a significantly higher amount of platinum into the cells and tumors expressing STn antigens. We also confirmed that a synergistic cytotoxic effect of sequential exposure of pancreatic cancer cells to Gem followed by CDDP can be mimicked by the codelivery of CDDP-loaded NGs (NG/CDDP) and free Gem. In a murine orthotopic model of PDAC, combined simultaneous treatment with Gem and targeted NG/CDDP significantly attenuated tumor growth with no detectable acute toxicity. Altogether, these results suggest that combination therapy consisting of Gem followed by TKH2-conjugated CDDP NGs induces highly synergistic therapeutic efficacy against pancreatic cancer. Our results offer the basis for development of combination drug regimens using targeted nanomedicines to increase treatment effectiveness and improve outcomes of PDAC therapy.

Alendronate-Modified Polymeric Micelles for the Treatment of Breast Cancer Bone Metastasis.

Although the prognosis of patients with breast cancer continues to improve, breast cancer metastasis to bones remains high in incidence and challenging to manage. Here, we report the development of bone-homing alendronate (ALN)-anchored biodegradable polymeric micelles for the targeted treatment of metastatic cancer to bone. These micelles exhibited bone protective capacity including the recruitment, differentiation, and resorption activity of the osteoclasts. Encapsulation of docetaxel (DTX), the first-line chemotherapeutic for treatment of metastatic breast cancer, in ALN-modified micelles results in a sustained release, enhanced cytotoxicity, and improved pharmacokinetics. In the syngeneic animal model of late-stage disseminated breast cancer bone metastasis, the treatment with targeted DTX-loaded micelles attenuated the tumorigenesis and significantly improved animal lifespan compared to the conventional surfactant-based formulation (free DTX). These findings indicate potential applications of the osteotropic nanomedicines for bone metastasis treatment.

Acetaldehyde accelerates HCV-induced impairment of innate immunity by suppressing methylation reactions in liver cells.

Alcohol exposure worsens the course and outcomes of hepatitis C virus (HCV) infection. Activation of protective antiviral genes is induced by IFN-α signaling, which is altered in liver cells by either HCV or ethanol exposure. However, the mechanisms of the combined effects of HCV and ethanol metabolism in IFN-α signaling modulation are not well elucidated. Here, we explored a possibility that ethanol metabolism potentiates HCV-mediated dysregulation of IFN-α signaling in liver cells via impairment of methylation reactions. HCV-infected Huh7.5 CYP2E1(+) cells and human hepatocytes were exposed to acetaldehyde (Ach)-generating system (AGS) and stimulated with IFN-α to activate IFN-sensitive genes (ISG) via the Jak-STAT-1 pathway. We observed significant suppression of signaling events by Ach. Ach exposure decreased STAT-1 methylation via activation of protein phosphatase 2A and increased the protein inhibitor of activated STAT-1 (PIAS-1)-STAT-1 complex formation in both HCV(+) and HCV(-) cells, preventing ISG activation. Treatment with a promethylating agent, betaine, attenuated all examined Ach-induced defects. Ethanol metabolism-induced changes in ISGs are methylation related and confirmed by in vivo studies on HCV(+) transgenic mice. HCV- and Ach-induced impairment of IFN signaling temporarily increased HCV RNA levels followed by apoptosis of heavily infected cells. We concluded that Ach potentiates the suppressive effects of HCV on activation of ISGs attributable to methylation-dependent dysregulation of IFN-α signaling. A temporary increase in HCV RNA sensitizes the liver cells to Ach-induced apoptosis. Betaine reverses the inhibitory effects of Ach on IFN signaling and thus can be used for treatment of HCV(+) alcohol-abusing patients.

Human hepatocytes and hematolymphoid dual reconstitution in treosulfan-conditioned uPA-NOG mice.

Human-specific HIV-1 and hepatitis co-infections significantly affect patient management and call for new therapeutic options. Small xenotransplantation models with human hepatocytes and hematolymphoid tissue should facilitate antiviral/antiretroviral drug trials. However, experience with mouse strains tested for dual reconstitution is limited, with technical difficulties such as risky manipulations with newborns and high mortality rates due to metabolic abnormalities. The best animal strains for hepatocyte transplantation are not optimal for human hematopoietic stem cell (HSC) engraftment, and vice versa. We evaluated a new strain of highly immunodeficient nonobese diabetic/Shi-scid (severe combined immunodeficiency)/IL-2Rγc(null) (NOG) mice that carry two copies of the mouse albumin promoter-driven urokinase-type plasminogen activator transgene for dual reconstitution with human liver and immune cells. Three approaches for dual reconstitution were evaluated: i) freshly isolated fetal hepatoblasts were injected intrasplenically, followed by transplantation of cryopreserved HSCs obtained from the same tissue samples 1 month later after treosulfan conditioning; ii) treosulfan conditioning is followed by intrasplenic simultaneous transplantation of fetal hepatoblasts and HSCs; and iii) transplantation of mature hepatocytes is followed by mismatched HSCs. The long-term dual reconstitution was achieved on urokinase-type plasminogen activator-NOG mice with mature hepatocytes (not fetal hepatoblasts) and HSCs. Even major histocompatibility complex mismatched transplantation was sustained without any evidence of hepatocyte rejection by the human immune system.

Nanoneuromedicines for degenerative, inflammatory, and infectious nervous system diseases.

Interest in nanoneuromedicine has grown rapidly due to the immediate need for improved biomarkers and therapies for psychiatric, developmental, traumatic, inflammatory, infectious and degenerative nervous system disorders. These, in whole or in part, are a significant societal burden due to growth in numbers of affected people and in disease severity. Lost productivity of the patient and his or her caregiver, and the emotional and financial burden cannot be overstated. The need for improved health care, treatment and diagnostics is immediate. A means to such an end is nanotechnology. Indeed, recent developments of health-care enabling nanotechnologies and nanomedicines range from biomarker discovery including neuroimaging to therapeutic applications for degenerative, inflammatory and infectious disorders of the nervous system. This review focuses on the current and future potential of the field to positively affect clinical outcomes. From the clinical editor: Many nervous system disorders remain unresolved clinical problems. In many cases, drug agents simply cannot cross the blood-brain barrier (BBB) into the nervous system. The advent of nanomedicines can enhance the delivery of biologically active molecules for targeted therapy and imaging. This review focused on the use of nanotechnology for degenerative, inflammatory, and infectious diseases in the nervous system.

Granulocytic myeloid-derived suppressor cell activity during biofilm infection is regulated by a glycolysis/HIF1a axis.

Staphylococcus aureus is a leading cause of biofilm-associated prosthetic joint infection (PJI). A primary contributor to infection chronicity is an expansion of granulocytic myeloid-derived suppressor cells (G-MDSCs), which are critical for orchestrating the antiinflammatory biofilm milieu. Single-cell sequencing and bioinformatic metabolic algorithms were used to explore the link between G-MDSC metabolism and S. aureus PJI outcome. Glycolysis and the hypoxia response through HIF1a were significantly enriched in G-MDSCs. Interfering with both pathways in vivo, using a 2-deoxyglucose nanopreparation and granulocyte-targeted Hif1a conditional KO mice, respectively, attenuated G-MDSC-mediated immunosuppression and reduced bacterial burden in a mouse model of S. aureus PJI. In addition, single-cell RNA-Seq (scRNA-Seq) analysis of granulocytes from PJI patients also showed an enrichment in glycolysis and hypoxia-response genes. These findings support the importance of a glycolysis/HIF1a axis in promoting G-MDSC antiinflammatory activity and biofilm persistence during PJI.

LHRH-targeted nanogels as a delivery system for cisplatin to ovarian cancer.

Targeted drug delivery using multifunctional polymeric nanocarriers is a modern approach for cancer therapy. Our purpose was to prepare targeted nanogels for selective delivery of chemotherapeutic agent cisplatin to luteinizing hormone-releasing hormone (LHRH) receptor overexpressing tumor in vivo. Building blocks of such delivery systems consisted of innovative soft block copolymer nanogels with ionic cores serving as a reservoir for cisplatin (loading 35%) and a synthetic analogue of LHRH conjugated to the nanogels via poly(ethylene glycol) spacer. Covalent attachment of (D-Lys6)-LHRH to nanogels was shown to be possible without loss in either the ligand binding affinity or the nanogel drug incorporation ability. LHRH-nanogel accumulation was specific to the LHRH-receptor positive A2780 ovarian cancer cells and not toward LHRH-receptor negative SKOV-3 cells. The LHRH-nanogel cisplatin formulation was more effective and less toxic than equimolar doses of free cisplatin or untargeted nanogels in the treatment of receptor-positive ovarian cancer xenografts in mice. Collectively, the study indicates that LHRH mediated nanogel-cisplatin delivery is a promising formulation strategy for therapy of tumors that express the LHRH receptor.

Macrophage folate receptor-targeted antiretroviral therapy facilitates drug entry, retention, antiretroviral activities and biodistribution for reduction of human immunodeficiency virus infections.

Macrophages serve as vehicles for the carriage and delivery of polymer-coated nanoformulated antiretroviral therapy (nanoART). Although superior to native drug, high drug concentrations are required for viral inhibition. Herein, folate-modified ritonavir-boosted atazanavir (ATV/r)-encased polymers facilitated macrophage receptor targeting for optimizing drug dosing. Folate coating of nanoART ATV/r significantly enhanced cell uptake, retention and antiretroviral activities without altering cell viability. Enhanced retentions of folate-coated nanoART within recycling endosomes provided a stable subcellular drug depot. Importantly, up to a five-fold enhanced plasma and tissue drug levels followed folate-coated formulation injection in mice. Folate polymer encased ATV/r improves nanoART pharmacokinetics bringing the technology one step closer to human use. FROM THE CLINICAL EDITOR: This team of authors describes a novel method for macrophage folate receptor-targeted antiretroviral therapy. Atazanvir entry, retention, and antiretroviral activities were superior using the presented method, and so was its biodistribution, enabling a more efficient way to address human immunodeficiency virus infections, with a hoped for clinical application in the near future.

Ligand-installed polymeric nanocarriers for combination chemotherapy of EGFR-positive ovarian cancer.

Combination chemotherapeutic drugs administered via a single nanocarrier for cancer treatment provides benefits in reducing dose-limiting toxicities, improving the pharmacokinetic properties of the cargo and achieving spatial-temporal synchronization of drug exposure for maximized synergistic therapeutic effects. In an attempt to develop such a multi-drug carrier, our work focuses on functional multimodal polypeptide-based polymeric nanogels (NGs). Diblock copolymers poly (ethylene glycol)-b-poly (glutamic acid) (PEG-b-PGlu) modified with phenylalanine (Phe) were successfully synthesized and characterized. Self-assembly behavior of the resulting polymers was utilized for the synthesis of NGs with hydrophobic domains in cross-linked polyion cores coated with inert PEG chains. The resulting NGs were small (ca. 70 nm in diameter) and were able to encapsulate the combination of drugs with different physicochemical properties such as cisplatin and neratinib. Drug combination-loaded NGs exerted a selective synergistic cytotoxicity towards EGFR overexpressing ovarian cancer cells. Moreover, we developed ligand-installed EGFR-targeted NGs and tested them as an EGFR-overexpressing tumor-specific delivery system. Both in vitro and in vivo, ligand-installed NGs displayed preferential associations with EGFR (+) tumor cells. Ligand-installed NGs carrying cisplatin and neratinib significantly improved the treatment response of ovarian cancer xenografts. We also confirmed the importance of simultaneous administration of the dual drug combination via a single NG system which provides more therapeutic benefit than individual drug-loaded NGs administered at equivalent doses. This work illustrates the potential of our carrier system to mediate efficient delivery of a drug combination to treat EGFR overexpressing cancers.

Synergistic combinations of multiple chemotherapeutic agents in high capacity poly(2-oxazoline) micelles.

Many effective drugs for cancer treatment are poorly water-soluble. In combination chemotherapy, needed excipients in additive formulations are often toxic and restrict their applications in clinical intervention. Here, we report on amphiphilic poly(2-oxazoline)s (POx) micelles as a promising high capacity delivery platform for multidrug cancer chemotherapy. A variety of binary and ternary drugs combinations of paclitaxel (PTX), docetaxel (DTX), 17-allylamino-17-demethoxygeldanamycin (17-AAG), etoposide (ETO) and bortezomib (BTZ) were solubilized in defined polymeric micelles achieving unprecedented high total loading capacities of up to 50 wt % drug per final formulation. Multidrug loaded POx micelles showed enhanced stability in comparison to single-drug loaded micelles. Drug ratio dependent synergistic cytotoxicity of micellar ETO/17-AAG was observed in MCF-7 cancer cells and of micellar BTZ/17-AAG in MCF-7, PC3, MDA-MB-231 and HepG2 cells.

Cross-linked antioxidant nanozymes for improved delivery to CNS.

Formulations of antioxidant enzymes, superoxide dismutase 1 (SOD1, also known as Cu/Zn SOD) and catalase were prepared by electrostatic coupling of enzymes with cationic block copolymers, polyethyleneimine-poly(ethylene glycol) or poly(L-lysine)-poly(ethylene glycol), followed by covalent cross-linking to stabilize nanoparticles (NPs). Different cross-linking strategies (using glutaraldehyde, bis-(sulfosuccinimidyl)suberate sodium salt or 1-Ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride with N-hydroxysulfosuccinimide) and reaction conditions (pH and polycation/protein charge ratio) were investigated that allowed immobilizing active enzymes in cross-linked NPs, termed "nanozymes." Bienzyme NPs, containing both SOD1 and catalase were also formulated. Formation of complexes was confirmed using denaturing gel electrophoresis and western blotting; physicochemical characterization was conducted using dynamic light scattering and atomic force microscopy. In vivo studies of (125)I-labeled SOD1-containing nanozymes in mice demonstrated their increased stability in both blood and brain and increased accumulation in brain tissues, in comparison with non-cross-linked complexes and native SOD1. Future studies will evaluate the potential of these formulations for delivery of antioxidant enzymes to the central nervous system to attenuate oxidative stress associated with neurological diseases. FROM THE CLINICAL EDITOR: Formulations of antioxidant enzyme complexes were demonstrated along with their increased stability in both blood and brain and increased accumulation in CNS tissue. Future studies will evaluate the potential of these formulations for antioxidant enzyme deliver to the CNS to attenuate oxidative stress in neurodegenerative diseases.

A Hydrogel Ionic Circuit Based High-Intensity Iontophoresis Device for Intraocular Macromolecule and Nanoparticle Delivery.

Iontophoresis is an electrical-current-based, noninvasive drug-delivery technology, which is particularly suitable for intraocular drug delivery. Current ocular iontophoresis devices use low current intensities that significantly limit macromolecule and nanoparticle (NP) delivery efficiency. Increasing current intensity leads to ocular tissue damage. Here, an iontophoresis device based on a hydrogel ionic circuit (HIC), for high-efficiency intraocular macromolecule and NP delivery, is described. The HIC-based device is capable of minimizing Joule heating, effectively buffering electrochemical (EC) reaction-generated pH changes, and absorbing electrode overpotential-induced heating. As a result, the device allows safe application of high current intensities (up to 87 mA cm-2 , more than 10 times higher than current ocular iontophoresis devices) to the eye with minimal ocular cell death and tissue damage. The high-intensity iontophoresis significantly enhances macromolecule and NP delivery to both the anterior and posterior segments by up to 300 times compared to the conventional iontophoresis. Therapeutically effective concentrations of bevacizumab and dexamethasone are delivered to target tissue compartments within 10-20 min of iontophoresis application. This study highlights the significant safety enhancement enabled by an HIC-based device design and the potential of the device to deliver therapeutic doses of macromolecule and NP ophthalmic drugs within a clinically relevant time frame.

Polyelectrolyte Nanogels Decorated with Monoclonal Antibody for Targeted Drug Delivery.

Novel surface-functionalized cross-linked nanogels were developed as a platform to allow conjugation of monoclonal antibodies (mAb) for targeted drug delivery. Well-defined diblock copolymers of poly(ethylene glycol)-b-poly(methacrylic acid) (PEG-b-PMA) with PEG terminal aldehyde functionality were synthesized by atom transfer radical polymerization (ATRP) and characterized by GPC and (1)H NMR. These copolymers were used to prepare nanogels via condensation of PEG-b-PMA with Ca(2+) ions into micelle-like aggregates, cross-linking of the PMA/Ca(2+) cores and removal of Ca(2+) ions. The resulting nanogels represent highly swollen spherical polyelectrolyte particles with free terminal aldehyde functionalities at the nonionic PEG chains. A reductive amination reaction between aldehyde groups and amino groups of mAb resulted in effective conjugation to the nanogels of mAb CC49 against tumor-associated glycoprotein 72 (TAG-72). The mAb retained the binding affinity to bovine submaxillary mucin after conjugation as shown by surface plasmon resonance (SPR). Therefore, aldehyde functionalized nanogels can be linked to mAb using a simple, one-step approach. They may have potential for targeted delivery of diagnostic and therapeutic agents to tumors.

Nanoscale platform for delivery of active IRINOX to combat pancreatic cancer.

Due to its late diagnosis and dismal prognosis, pancreatic ductal adenocarcinoma (PDAC) is one of the most devastating solid malignancies, with only 9% of patients surviving after being diagnosed. A multidrug chemotherapeutic regimen FOL-F-IRIN-OX (combination of 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin) offers survival benefits superior to that of gemcitabine single agent, but the treatment-related side effects are also severe. To overcome this therapeutic barrier, we developed polymeric micelles bearing active formats of irinotecan and oxaliplatin, SN38 and 1,2-diaminocyclohexane­platinum (II), DACHPt. Crosslinked micelles were prepared using amphiphilic PEG-b-poly(L-glutamic acid)/SN38 conjugates and subsequently loaded with DACHPt. The dual drug-loaded micelles exhibited improved colloidal stability, prolonged drug release and remarkable cytotoxicity in human pancreatic cancer cell lines and KrasG12D; Trp52R172H/+; Pdx-1 Cre murine tumor organoids models. In vivo, (SN38 + DACHPt)-loaded micelles displayed superior antitumor and antimetastatic activities without impairing safety. Our results suggest that nanomedicine mimicking irinotecan and oxaliplatin as parts of FOLFIRINOX regimen may further improve the feasibility of this multidrug treatment for patients with advanced pancreatic cancer.

Mannosylated Cationic Copolymers for Gene Delivery to Macrophages.

Macrophages are desirable targets for gene therapy of cancer and other diseases. Cationic diblock copolymers of polyethylene glycol (PEG) and poly-L-lysine (PLL) or poly{N-[N-(2-aminoethyl)-2-aminoethyl]aspartamide} (pAsp(DET)) are synthesized and used to form polyplexes with a plasmid DNA (pDNA) that are decorated with mannose moieties, serving as the targeting ligands for the C type lectin receptors displayed at the surface of macrophages. The PEG-b-PLL copolymers are known for its cytotoxicity, so PEG-b-PLL-based polyplexes are cross-linked using reducible reagent dithiobis(succinimidyl propionate) (DSP). The cross-linked polyplexes display low toxicity to both mouse embryonic fibroblasts NIH/3T3 cell line and mouse bone marrow-derived macrophages (BMMΦ). In macrophages mannose-decorated polyplexes demonstrate an ≈8 times higher transfection efficiency. The cross-linking of the polyplexes decrease the toxicity, but the transfection enhancement is moderate. The PEG-b-pAsp(DET) copolymers display low toxicity with respect to the IC-21 murine macrophage cell line and are used for the production of non-cross-linked pDNA-contained polyplexes. The obtained mannose modified polyplexes exhibit ca. 500-times greater transfection activity in IC-21 macrophages compared to the mannose-free polyplexes. This result greatly exceeds the targeting gene transfer effects previously described using mannose receptor targeted non-viral gene delivery systems. These results suggest that Man-PEG-b-pAsp(DET)/pDNA polyplex is a potential vector for immune cells-based gene therapy.

Nanoformulation design and therapeutic potential of a novel tubulin inhibitor in pancreatic cancer.

Successful treatment of pancreatic cancer remains a challenge due to desmoplasia, development of chemoresistance, and systemic toxicity. Herein, we synthesized (6-(3-hydroxy-4-methoxylphenyl)pyridin-2-yl) (3,4,5-trimethoxyphenyl)methanone (CH-3-8), a novel microtubule polymerization inhibitor with little susceptible to transporter-mediated chemoresistance. CH-3-8 binding to the colchicine-binding site in tubulin protein was confirmed by tubulin polymerization assay and molecular modeling. CH-3-8 disrupted microtubule dynamics at the nanomolar concentration in MIA PaCa-2 and PANC-1 pancreatic cancer cell lines. CH-3-8 significantly inhibited the proliferation of these cells, induced G2/M cell cycle arrest, and led to apoptosis. CH-3-8 is hydrophobic with an aqueous solubility of 0.97 ± 0.16 µg/mL at pH 7.4. We further conjugated it with dodecanol through diglycolate linker to increase hydrophobicity and thus loading in lipid-based delivery systems. Hence, we encapsulated CH-3-8 lipid conjugate (LDC) into methoxy poly(ethylene glycol)-block-poly(2-methyl-2-carboxyl-propylene carbonate-graft-dodecanol) (mPEG-b-PCC-g-DC) polymeric nanoparticles (NPs) by solvent evaporation, resulting in a mean particle size of 125.6 ± 2.3 nm and drug loading of 10 ± 1.0% (w/w) while the same polymer could only load 1.6 ± 0.4 (w/w) CH-3-8 using the same method. Systemic administration of 6 doses of CH-3-8 and LDC loaded NPs at the dose of 20 mg/kg into orthotopic pancreatic tumor-bearing NSG mice every alternate day resulted in significant tumor regression. Systemic toxicity was negligible, as evidenced by histological evaluations. In conclusion, CH-3-8 LDC loaded NPs have the potential to improve outcomes of pancreatic cancer by overcoming transporter-mediated chemoresistance and reducing systemic toxicity.

Androgen Receptor, Although Not a Specific Marker For, Is a Novel Target to Suppress Glioma Stem Cells as a Therapeutic Strategy for Glioblastoma.

Targeting androgen receptor (AR) has been shown to be promising in treating glioblastoma (GBM) in cell culture and flank implant models but the mechanisms remain unclear. AR antagonists including enzalutamide are available for treating prostate cancer patients in clinic and can pass the blood-brain barrier, thus are potentially good candidates for GBM treatment but have not been tested in GBM orthotopically. Our current studies confirmed that in patients, a majority of GBM tumors overexpress AR in both genders. Enzalutamide inhibited the proliferation of GBM cells both in vitro and in vivo. Although confocal microscopy demonstrated that AR is expressed but not specifically in glioma cancer stem cells (CSCs) (CD133+), enzalutamide treatment significantly decreased CSC population in cultured monolayer cells and spheroids, suppressed tumor sphere-forming capacity of GBM cells, and downregulated CSC gene expression at mRNA and protein levels in a dose- and time-dependent manner. We have, for the first time, demonstrated that enzalutamide treatment decreased the density of CSCs in vivo and improved survival in an orthotopic GBM mouse model. We conclude that AR antagonists potently target glioma CSCs in addition to suppressing the overall proliferation of GBM cells as a mechanism supporting their repurposing for clinical applications treating GBM.