Intestinal Barrier Dysfunction in Fatty Liver Disease: Roles of Microbiota, Mucosal Immune System, and Bile Acids.

Nonalcoholic fatty liver disease (NAFLD) describes a spectrum of progressive liver diseases ranging from simple steatosis to steatohepatitis and fibrosis. Globally, NAFLD is the leading cause of morbidity and mortality associated with chronic liver disease, and NAFLD patients are at a higher risk of developing cirrhosis and hepatocellular carcinoma. While there is a consensus that inflammation plays a key role in promoting NAFLD progression, the underlying mechanisms are not well understood. Recent clinical and experimental evidence suggest that increased hepatic translocation of gut microbial antigens, secondary to diet-induced impairment of the intestinal barrier may be important in driving hepatic inflammation in NAFLD. Here, we briefly review various endogenous and exogenous factors influencing the intestinal barrier and present recent advances in our understanding of cellular and molecular mechanisms underlying intestinal barrier dysfunction in NAFLD.

Western diet-induced increase in colonic bile acids compromises epithelial barrier in nonalcoholic steatohepatitis.

There is compelling evidence implicating intestinal permeability in the pathogenesis of nonalcoholic steatohepatitis (NASH), but the underlying mechanisms remain poorly understood. Here we examined the role of bile acids (BA) in western diet (WD)-induced loss of colonic epithelial barrier (CEB) function in mice with a genetic impairment in intestinal epithelial barrier function, junctional adhesion molecule A knockout mice, F11r-/- . WD-fed knockout mice developed severe NASH, which was associated with increased BA concentration in the cecum and loss of CEB function. Analysis of cecal BA composition revealed selective increases in primary unconjugated BAs in the WD-fed mice, which correlated with increased abundance of microbial taxa linked to BA metabolism. In vitro permeability assays revealed that chenodeoxycholic acid (CDCA), which was elevated in the cecum of WD-fed mice, increased paracellular permeability, while the BA-binding resin sevelamer hydrochloride protected against CDCA-induced loss of barrier function. Sequestration of intestinal BAs by in vivo delivery of sevelamer to WD-fed knockout mice attenuated colonic mucosal inflammation and improved CEB. Sevelamer also reduced hepatic inflammation and fibrosis, and improved metabolic derangements associated with NASH. Collectively, these findings highlight a hitherto unappreciated role for BAs in WD-induced impairment of the intestinal epithelial barrier in NASH.

Blocking integrin α4ß7-mediated CD4 T cell recruitment to the intestine and liver protects mice from western diet-induced non-alcoholic steatohepatitis.

BACKGROUND & AIMS: The heterodimeric integrin receptor α4ß7 regulates CD4 T cell recruitment to inflamed tissues, but its role in the pathogenesis of non-alcoholic steatohepatitis (NASH) is unknown. Herein, we examined the role of α4ß7-mediated recruitment of CD4 T cells to the intestine and liver in NASH. METHODS: Male littermate F11r+/+ (control) and junctional adhesion molecule A knockout F11r-/- mice were fed a normal diet or a western diet (WD) for 8 weeks. Liver and intestinal tissues were analyzed by histology, quantitative reverse transcription PCR (qRT-PCR), 16s rRNA sequencing and flow cytometry. Colonic mucosa-associated microbiota were analyzed using 16s rRNA sequencing. Liver biopsies from patients with NASH were analyzed by confocal imaging and qRT-PCR. RESULTS: WD-fed knockout mice developed NASH and had increased hepatic and intestinal α4ß7+ CD4 T cells relative to control mice who developed mild hepatic steatosis. The increase in α4ß7+ CD4 T cells was associated with markedly higher expression of the α4ß7 ligand mucosal addressin cell adhesion molecule 1 (MAdCAM-1) in the colonic mucosa and livers of WD-fed knockout mice. Elevated MAdCAM-1 expression correlated with increased mucosa-associated Proteobacteria in the WD-fed knockout mice. Antibiotics reduced MAdCAM-1 expression indicating that the diet-altered microbiota promoted colonic and hepatic MAdCAM-1 expression. α4ß7 blockade in WD-fed knockout mice significantly decreased α4ß7+ CD4 T cell recruitment to the intestine and liver, attenuated hepatic inflammation and fibrosis, and improved metabolic indices. MAdCAM-1 blockade also reduced hepatic inflammation and fibrosis in WD-fed knockout mice. Hepatic MAdCAM-1 expression was elevated in patients with NASH and correlated with higher expression of α4 and ß7 integrins. CONCLUSIONS: These findings establish α4ß7/MAdCAM-1 as a critical axis regulating NASH development through colonic and hepatic CD4 T cell recruitment. LAY SUMMARY: Non-alcoholic steatohepatitis (NASH) is an advanced and progressive form of non-alcoholic fatty liver disease (NAFLD), and despite its growing incidence no therapies currently exist to halt NAFLD progression. Herein, we show that blocking integrin receptor α4ß7-mediated recruitment of CD4 T cells to the intestine and liver not only attenuates hepatic inflammation and fibrosis, but also improves metabolic derangements associated with NASH. These findings provide evidence for the potential therapeutic application of α4ß7 antibody in the treatment of human NASH.

Stealth Polymer-Coated Graphene Oxide Decorated Mesoporous Titania Nanoplatforms for In Vivo Chemo-Photodynamic Cancer Therapy.

PURPOSE: The goal of this study was to develop chemotherapeutic drug-loaded photoactivable stealth polymer-coated silica based- mesoporous titania nanoplatforms for enhanced antitumor activity. METHODS: Both in vitro and in vivo models of solvothermal treated photoactivable nanoplatforms were evaluated for efficient chemo-photothermal activity. A versatile nanocomposite that combined silica based- mesoporous titania nanocarriers (S-MTN) with the promising photoactivable agent, graphene oxide (G) modified with a stealth polymer (P) was fabricated to deliver chemotherapeutic agent, imatinib (I), (referred as S-MTN@IG-P) for near-infrared (NIR)-triggered drug delivery and enhanced chemo-photothermal therapy. RESULTS: The fabricated S-MTN@IG-P nanoplatform showed higher drug loading (~20%) and increased drug release (~60%) in response to light in acidic condition (pH 5.0). As prepared nanoplatform significantly converted NIR light into thermal energy (43.2°C) to produce reactive oxygen species (ROS). The pronounced cytotoxic effect was seen in both colon cancer cells (HCT-116 and HT-29) that was mediated through the chemotherapeutic effect of imatinib and the photothermal and ROS generation effects of graphene oxide. In vivo study also showed that S-MTN@IG-P could significantly accumulate into the tumor area and suppress the tumor growth under NIR irradiation without any biocompatibility issues. CONCLUSION: Cumulatively, the above results showed promising effects of S-MTN@IG-P for effective chemo-phototherapy of colon cancer.

Multifaceted NIR-responsive polymer-peptide-enveloped drug-loaded copper sulfide nanoplatform for chemo-phototherapy against highly tumorigenic prostate cancer.

Targeted, biocompatible, and synergistic "all in one" systems should be designed to combat the heterogeneity of cancer. In this study, we constructed a dual function nanosystem, copper sulfide nanoplatform loaded with the chemotherapeutic drug docetaxel wrapped by a conjugated polymer-peptide for targeted chemo-phototherapy. The nanoconstruct has been successfully designed with a size of 186.1 ±â€¯5.2 nm, a polydispersity index of 0.18 ±â€¯0.01, and zeta potential of -16.4 ±â€¯0.1 mV. The enhanced uptake and near-infrared-responsive behavior of the nanosystem resulted in efficient drug release, photothermal ablation, effective cytotoxic activity, and potentiated reactive oxygen species generation. The induction of apoptotic markers, enhanced accumulation in the tumor site, and maximum tumor growth inhibition were seen during in vivo studies compared to non-targeted nanoformulations and free drug. Cumulatively, our results indicate that, with low systemic toxicity and better biocompatibility, this nanoconstruct could provide a promising strategy for treating prostate cancer.

Engineered islet cell clusters transplanted into subcutaneous space are superior to pancreatic islets in diabetes.

An alternative route for pancreatic islet transplantation is the subcutaneous space; however, inadequate vascularization in the subcutaneous space limits the availability of oxygen and nutrients to the subcutaneously transplanted islets, which leads to the development of a necrotic core in the islets, thereby causing islet dysfunction. Thus, we aimed to prevent the early apoptosis of pancreatic islets after transplantation into subcutaneous space by preparing islet clusters of appropriate size. We prepared fully functional islet cell clusters (ICCs) by using the hanging-drop technique. We optimized the size of ICCs on the basis of viability and functionality after culture in an hypoxic environment. We transplanted ICCs into the subcutaneous space of diabetic mice and evaluated the viability of the islets at the transplantation site. In an hypoxic environment, ICCs exhibited improved viability and functionality compared with control islets. ICCs, upon transplantation into the hypoxic subcutaneous space of diabetic mice, showed better glycemic control compared with control islets. Live/dead imaging of the islets after retrieval from the transplanted area revealed significantly reduced apoptosis in ICCs. Transplantation of ICCs may be an attractive strategy to prevent islet cell apoptosis that results from nonimmune-mediated physiologic stress at the transplantation site.-Pathak, S., Regmi, S., Gupta, B., Pham, T. T., Yong, C. S., Kim, J. O., Yook, S., Kim, J.-R., Park, M. H., Bae, Y. K., Jeong, J.-H. Engineered islet cell clusters transplanted into subcutaneous space are superior to pancreatic islets in diabetes.

Paclitaxel and Erlotinib-co-loaded Solid Lipid Core Nanocapsules: Assessment of Physicochemical Characteristics and Cytotoxicity in Non-small Cell Lung Cancer.

PURPOSE: Lung cancer is the leading cause of cancer-related deaths. The aim of this study was to design solid lipid core nanocapsules (SLCN) comprising a solid lipid core and a PEGylated polymeric corona for paclitaxel (PTX) and erlotinib (ERL) co-delivery to non-small cell lung cancer (NSCLC), and evaluate their physicochemical characteristics and in vitro activity in NCI-H23 cells. METHODS: PTX/ERL-SLCN were prepared by nanoprecipitation and sonication and physicochemically characterized by dynamic light scattering, transmission electron microscopy, differential scanning calorimetry, X-ray diffraction, and Fourier-transform infrared spectroscopy. In vitro release profiles at pH 7.4 and pH 5.0 were studied and analyzed. In vitro cytotoxicity and cellular uptake and apoptosis assays were performed in NCI-H23 cells. RESULTS: PTX/ERL-SLCN exhibited appropriately-sized spherical particles with a high payload. Both PTX and ERL showed pH-dependent and sustained release in vitro profiles. PTX/ERL-SLCN demonstrated concentration- and time-dependent uptake by NCI-H23 cells and caused dose-dependent cytotoxicity in the cells, which was remarkably greater than that of not only the free individual drugs but also the free drug cocktail. Moreover, well-defined early and late apoptosis were observed with clearly visible signs of apoptotic nuclei. CONCLUSION: PTX/ERL-SLCN could be employed as an optimal approach for combination chemotherapy of NSCLC.

Preparation and Optimization of Immediate Release/Sustained Release Bilayered Tablets of Loxoprofen Using Box-Behnken Design.

The aim of our current study was to characterize and optimize loxoprofen immediate release (IR)/sustained release (SR) tablet utilizing a three-factor, three-level Box-Behnken design (BBD) combined with a desirability function. The independent factors included ratio of drug in the IR layer to total drug (X 1), ratio of HPMC to drug in the SR layer (X 2), and ratio of Eudragit RL PO to drug in the SR layer (X 3). The dependent variables assessed were % drug released in distilled water at 30 min (Y 1), % drug released in pH 1.2 at 2 h (Y 2), and % drug released in pH 6.8 at 12 h (Y 3). The responses were fitted to suitable models and statistical validation was performed using analysis of variance. In addition, response surface graphs and contour plots were constructed to determine the effects of different factor level combinations on the responses. The optimized loxoprofen IR/SR tablets were successfully prepared with the determined amounts of ingredients that showed close agreement in the predicted and experimental values of tablet characterization and drug dissolution profile. Therefore, BBD can be utilized for successful optimization of loxoprofen IR/SR tablet, which can be regarded as a suitable substitute for the current marketed formulations.

Preparation of High-Payload, Prolonged-Release Biodegradable Poly(lactic-co-glycolic acid)-Based Tacrolimus Microspheres Using the Single-Jet Electrospray Method.

Tacrolimus-loaded poly(lactic-co-glycolic acid) microspheres (TAC-PLGA-M) can be administered for the long-term survival of transplanted organs due to their immunosuppressive activity. The purpose of our study was to optimize the parameters of the electrospray method, and to prepare TAC-PLGA-M with a high payload and desirable release properties. TAC-PLGA-M were prepared using the electrospray method. In vitro characterization and evaluation were performed using scanning electron microscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier-transform infrared spectroscopy. Drug-loading efficiency was greater than 80% in all formulations with a maximum loading capacity of 16.81±0.37%. XRD and DSC studies suggested that the drug was incorporated in an amorphous state or was molecularly dispersed in the microspheres. The in vitro release study showed prolonged release patterns. TAC-PLGA-M with enhanced drug loading and prolonged-release patterns were successfully prepared using the electrospray method.

Effects of Formulation Variables on the Particle Size and Drug Encapsulation of Imatinib-Loaded Solid Lipid Nanoparticles.

Imatinib (IMT), an anticancer agent, inhibits receptor tyrosine kinases and is characterized by poor aqueous solubility, extensive first-pass metabolism, and rapid clearance. The aims of the current study are to prepare imatinib-loaded solid lipid nanoparticles (IMT-SLN) and study the effects of associated formulation variables on particle size and drug encapsulation on IMT-SLN using an experimental design. IMT-SLN was optimized by use of a "combo" approach involving Plackett-Burman design (PBD) and Box-Behnken design (BBD). PBD screening resulted in the determination of organic-to-aqueous phase ratio (O/A), drug-to-lipid ratio (D/L), and amount of Tween® 20 (Tw20) as three significant variables for particle size (S z), drug loading (DL), and encapsulation efficiency (EE) of IMT-SLN, which were used for optimization by BBD, yielding an optimized criteria of O/A = 0.04, D/L = 0.03, and Tw20 = 2.50% w/v. The optimized IMT-SLN exhibited monodispersed particles with a size range of 69.0 ± 0.9 nm, ζ-potential of -24.2 ± 1.2 mV, and DL and EE of 2.9 ± 0.1 and 97.6 ± 0.1% w/w, respectively. Results of in vitro release study showed a sustained release pattern, presumably by diffusion and erosion, with a higher release rate at pH 5.0, compared to pH 7.4. In conclusion, use of the combo experimental design approach enabled clear understanding of the effects of various formulation variables on IMT-SLN and aided in the preparation of a system which exhibited desirable physicochemical and release characteristics.

Modulation of Pharmacokinetic and Cytotoxicity Profile of Imatinib Base by Employing Optimized Nanostructured Lipid Carriers.

PURPOSE: To prepare, optimize and characterize imatinib-loaded nanostructured lipid carriers (IMT-NLC), and evaluate their pharmacokinetic and cytotoxicity characteristics. METHODS: IMT-NLC was prepared by hot homogenization method, and optimized by an approach involving Plackett-Burman design (PBD) and central composite design (CCD). An in vivo pharmacokinetic study was conducted in rats after both oral and intravenous administration. The in vitro cytotoxicity was evaluated by MTT assay on NCI-H727 cell-lines. RESULTS: PBD screening, followed by optimization by CCD and desirability function, yielded an optimized condition of 0.054, 6% w/w, 2.5% w/w and 1.25% w/v for organic-to-aqueous phase ratio (O/A), drug-to-lipid ratio (D/L), amount of lecithin (Lec) and amount of Tween® 20 (Tw20) respectively. The optimized IMT-NLC exhibited a particle size (Sz) of 148.80 ± 1.37 nm, polydispersity index (PDI) 0.191 ± 0.017 of and ζ-potential of -23.0 ± 1.5 mV, with a drug loading (DL) of 5.48 ± 0.01% and encapsulation efficiency (EE) of 97.93 ± 0.03%. IMT-NLC displayed sustained IMT release in vitro, significantly enhanced in vivo bioavailability of IMT after intravenous and oral administration, and greater in vitro cytotoxicity on NCI-H727 cells, compared with free IMT. CONCLUSION: A combined DoE approach enabled accurate optimization and successful preparation of IMT-NLC with enhanced in vivo pharmacokinetic and in vitro cytotoxicity characteristics.

Selective Targeting of α4ß7/MAdCAM-1 Axis Suppresses Fibrosis Progression by Reducing Proinflammatory T Cell Recruitment to the Liver.

Integrin α4ß7+ T cells perpetuate tissue injury in chronic inflammatory diseases, yet their role in hepatic fibrosis progression remains poorly understood. Here, we report increased accumulation of α4ß7+ T cells in the liver of people with cirrhosis relative to disease controls. Similarly, hepatic fibrosis in the established mouse model of CCl4-induced liver fibrosis was associated with enrichment of intrahepatic α4ß7+ CD4 and CD8 T cells. Monoclonal antibody (mAb)-mediated blockade of α4ß7 or its ligand mucosal addressin cell adhesion molecule (MAdCAM)-1 attenuated hepatic inflammation and prevented fibrosis progression in CCl4-treated mice. Improvement in liver fibrosis was associated with a significant decrease in the infiltration of α4ß7+ CD4 and CD8 T cells, suggesting that α4ß7/MAdCAM-1 axis regulates both CD4 and CD8 T cell recruitment to the fibrotic liver, and α4ß7+ T cells promote hepatic fibrosis progression. Analysis of hepatic α4ß7+ and α4ß7- CD4 T cells revealed that α4ß7+ CD4 T cells were enriched for markers of activation and proliferation, demonstrating an effector phenotype. The findings suggest that α4ß7+ T cells play a critical role in promoting hepatic fibrosis progression, and mAb-mediated blockade of α4ß7 or MAdCAM-1 represents a promising therapeutic strategy for slowing hepatic fibrosis progression in chronic liver diseases.

Selective targeting of α 4 ß 7 /MAdCAM-1 axis suppresses liver fibrosis by reducing proinflammatory T cell recruitment to the liver.

Integrin α 4 ß 7 + T cells perpetuate tissue injury in chronic inflammatory diseases, yet their role in hepatic fibrosis progression remains poorly understood. Here we report increased accumulation of α 4 ß 7 + T cells in the liver of people with cirrhosis relative to disease controls. Similarly, hepatic fibrosis in the established mouse model of CCl 4 -induced liver fibrosis was associated with enrichment of intrahepatic α 4 ß 7 + CD4 and CD8 T cells. Monoclonal antibody (mAb)-mediated blockade of α 4 ß 7 or its ligand mucosal addressin cell adhesion molecule (MAdCAM)-1 attenuated hepatic inflammation and prevented fibrosis progression in CCl 4 treated mice. Improvement in liver fibrosis was associated with a significant decrease in the infiltration of α 4 ß 7 + CD4 and CD8 T cells suggesting that α 4 ß 7 /MAdCAM-1 axis regulates both CD4 and CD8 T cell recruitment to the fibrotic liver, and α 4 ß 7 + T cells promote hepatic fibrosis progression. Analysis of hepatic α 4 ß 7 + and α 4 ß 7 -CD4 T cells revealed that α 4 ß 7 + CD4 T cells enriched for markers of activation and proliferation demonstrating an effector phenotype. Notably, blockade of α 4 ß 7 or MAdCAM-1 did not affect the recruitment of Foxp3+ regulatory T cells, demonstrating the specificity of α 4 ß 7 /MAdCAM-1 axis in regulating effector T cell recruitment to the liver. The findings suggest that α 4 ß 7 + T cells play a critical role in promoting hepatic fibrosis progression, and mAb-mediated blockade of α 4 ß 7 or MAdCAM-1 represents a promising therapeutic strategy for slowing hepatic fibrosis progression in chronic liver diseases.

Tie2-mediated vascular remodeling by ferritin-based protein C nanoparticles confers antitumor and anti-metastatic activities.

BACKGROUND: Conventional therapeutic approaches for tumor angiogenesis, which are primarily focused on the inhibition of active angiogenesis to starve cancerous cells, target the vascular endothelial growth factor signaling pathway. This aggravates hypoxia within the tumor core and ultimately leads to increased tumor proliferation and metastasis. To overcome this limitation, we developed nanoparticles with antiseptic activity that target tumor vascular abnormalities. METHODS: Ferritin-based protein C nanoparticles (PCNs), known as TFG and TFMG, were generated and tested in Lewis lung carcinoma (LLC) allograft and MMTV-PyMT spontaneous breast cancer models. Immunohistochemical analysis was performed on tumor samples to evaluate the tumor vasculature. Western blot and permeability assays were used to explore the role and mechanism of the antitumor effects of PCNs in vivo. For knocking down proteins of interest, endothelial cells were transfected with siRNAs. Statistical analysis was performed using one-way ANOVA followed by post hoc Dunnett's multiple comparison test. RESULTS: PCNs significantly inhibited hypoxia and increased pericyte coverage, leading to the inhibition of tumor growth and metastasis, while increasing survival in LLC allograft and MMTV-PyMT spontaneous breast cancer models. The coadministration of cisplatin with PCNs induced a synergistic suppression of tumor growth by improving drug delivery as evidenced by increased blood prefusion and decreased vascular permeability. Moreover, PCNs altered the immune cell profiles within the tumor by increasing cytotoxic T cells and M1-like macrophages with antitumor activity. PCNs induced PAR-1/PAR-3 heterodimerization through EPCR occupation and PAR-1 activation, which resulted in Gα13-RhoA-mediated-Tie2 activation and stabilized vascular tight junctions via the Akt-FoxO3a signaling pathway. CONCLUSIONS: Cancer treatment targeting the tumor vasculature by inducing antitumor immune responses and enhancing the delivery of a chemotherapeutic agent with PCNs resulted in tumor regression and may provide an effective therapeutic strategy.

Phytosterol-loaded CD44 receptor-targeted PEGylated nano-hybrid phyto-liposomes for synergistic chemotherapy.

Background: Phytosterols significantly reduce the risk of cancer by directly inhibiting tumor growth, inducing apoptosis, and inhibiting tumor metastasis. Stigmasterol (STS), a phytosterol, exhibits anticancer effects against various cancers, including breast cancer. Chemotherapeutics, including doxorubicin (DOX), might act synergistically with phytosterol against the proliferation and metastasis of breast cancer. Although such compounds can show potential anticancer activity, their combined effect with suitable formulation has not investigated yet.Methods: Hyaluronic acid (HA)-modified PEGylated DOX-STS loaded phyto-liposome was fabricated via a thin-film hydration method. The prepared phyto-liposome was optimized with regards to its physicochemical and other properties. Further, in vitro and in vivo study was carried out in breast cancer cells expressing a different level of CD44 receptors.Results: The particle size of prepared HA-DOX-STS-lipo was 173.9 ± 2.4 nm, and showed pH-depended DOX release, favoring the effective tumor targetability. The in vitro anticancer activity of HA-DOX-STS-lipo was significantly enhanced in MDA-MB-231, CD44-overexpressing cells relative to MCF-7 cells demonstrating HA-mediated targeting effect. HA-DOX-STS-lipo accumulated more and increased antitumor efficacy in the MDA-MB-231 xenograft tumor model expressing high levels of CD44, suggesting the potential of carrier system toward CD44-overexpressing tumors.

Tailored Black Phosphorus for Erythrocyte Membrane Nanocloaking with Interleukin-1α siRNA and Paclitaxel for Targeted, Durable, and Mild Combination Cancer Therapy.

Several therapeutic nanosystems have been engineered to remedy the shortcomings of cancer monotherapies, including immunotherapy (stimulating the host immune system to eradicate cancer), to improve therapeutic efficacy with minimizing off-target effects and tumor-induced immunosuppression. Light-activated components in nanosystems confer additional phototherapeutic effects as combinatorial modalities; however, systemic and thermal toxicities with unfavorable accumulation and excretion of nanoystem components now hamper their practical applications. Thus, there remains a need for optimal multifunctional nanosystems to enhance targeted, durable, and mild combination therapies for efficient cancer treatment without notable side effects. Methods: A nanosystem constructed with a base core (poly-L-histidine [H]-grafted black phosphorus [BP]) and a shell (erythrocyte membrane [EM]) is developed to offer a mild photoresponsive (near-infrared) activity with erythrocyte mimicry. In-flight electrostatic tailoring to extract uniform BP nanoparticles maintains a hydrodynamic size of <200 nm (enabling enhanced permeability and retention) after EM cloaking and enhances their biocompatibility. Results: Ephrin-A2 receptor-specific peptide (YSA, targeting cancer cells), interleukin-1α silencing small interfering RNA (ILsi, restricting regulatory T cell trafficking), and paclitaxel (X, inducing durable chemotherapeutics) are incorporated within the base core@shell constructs to create BP-H-ILsi-X@EM-YSA architectures, which provide a more intelligent nanosystem for combination cancer therapies. Conclusion: The in-flight tailoring of BP particles provides a promising base core for fabricating <200 nm EM-mimicking multifunctional nanosystems, which could be beneficial for constructing smarter nanoarchitectures to use in combination cancer therapies.

Aerosol technique-based carbon-encapsulated hollow mesoporous silica nanoparticles for synergistic chemo-photothermal therapy.

Near-infrared (NIR)-responsive drug delivery systems have enhanced tumor ablative efficiency through permeation and retention effects. Graphene oxide (GO) has shown great potential both in photothermal therapy and in drug delivery. Thus, in this study, we designed an ambient spark-generated GO, wrapped on topotecan (TPT)-loaded hollow mesoporous silica nanoparticles (HMSN-NH2-TPT-CGO), to function as an efficient platform for pH-dependent sustained release of TPT. HMSN-NH2-TPT-CGO also exhibited a combined chemo-photothermal effect within a single carrier system. This developed system was stable with a uniform particle size (∼190 nm) and was demonstrated to possess a sufficient heat-absorbing capacity to induce tumor cell ablation. We performed the ablation of tumor cells both in vitro and in vivo in combination with photothermal therapy and chemotherapy using the spark-generated functional GO and HMSN. The prepared nanocarriers demonstrated high cellular uptake, apoptosis, and G0/G1 cell cycle arrest. In vivo study using the MDA-MB-231 xenograft model revealed the ultraefficient tumor ablative performance of HMSN-NH2-TPT-CGO compared with that of free TPT, with no toxic effect on vital organs. Altogether, the optimized nanocarriers presented a significant potential to act as a vehicle for cancer treatment. STATEMENT OF SIGNIFICANCE: This is the first study that uses spark-generated graphene oxide nanoflakes to cover the topotecan (TPT)-loaded hollow mesoporous silica nanoparticles (HMSNs) to treat breast cancer. Dense silica was used as a hard template to prepare the HMSNs attributing to a high drug payload. The concentration of Na2CO3 was precisely controlled to minimize the silica etching time within 70 min. The use of the nanographene flakes served a dual purpose, first, by acting as a capping agent to prevent the premature release of drug and, second, by serving as a nano heater that significantly ablates the tumor cells. The prepared nanocarriers (NCs) exhibited effective and enhanced in vitro and in vivo apoptosis, as well as significant tumor growth inhibition even after 15 days of treatment time, with no toxic effect to the vital organs. The NCs enhanced in vitro tumor cell killing effects and served as an effective carrier for in vivo tumor regression, thereby highlighting the enormous potential of this system for breast cancer therapy.

PEGylated polyaminoacid-capped mesoporous silica nanoparticles for mitochondria-targeted delivery of celastrol in solid tumors.

The major goal of cancer chemotherapy is to maximize the therapeutic efficacy of anticancer drugs, while minimizing their associated side effects. Celastrol (CST), which is extracted from the traditional Chinese medicinal plant Tripterygium wilfordii, has been reported to exhibit significant anticancer effects in various in vitro and in vivo cancer models. Nanoparticulate drug delivery systems could be employed to preserve and enhance the pharmacological effects of CST in cancer cells. Among these, mesoporous silica nanoparticles (MSNs) are one of the most promising drug delivery systems. MSNs possess the capability of passive accumulation within solid tumors, and could efficiently transport anticancer drugs to such tumors in a site-specific manner. In this study, PEGylated polyaminoacid-capped CST-loaded MSN (CMSN-PEG) showed controlled in vitro drug release behavior, and exhibited high in vitro cytotoxicity in different cancer cells. Compared to treatment with free CST, treatment with CMSN-PEG resulted in the increased expression of the apoptosis protein HIF-1α and proteins corresponding to mitochondrial apoptosis pathway. Importantly, CMSN-PEG remarkably reduced tumor burden with no toxicity to healthy cells in the SCC7 tumor-bearing xenograft model. Our results clearly demonstrate a promising potential of CMSN-PEG for the treatment of solid tumors.

Polyamino Acid Layer-by-Layer (LbL) Constructed Silica-Supported Mesoporous Titania Nanocarriers for Stimuli-Responsive Delivery of microRNA 708 and Paclitaxel for Combined Chemotherapy.

Cellular Fas-associated protein with death domain-like interleukin-1ß-converting enzyme-inhibitory protein (c-FLIP), often strongly expressed in numerous cancers, plays a pivotal role in thwarting apoptosis and inducing chemotherapy resistance in cancer. An integrated approach combining chemotherapy with suppression of c-FLIP levels could prove paramount in the treatment of cancers with c-FLIP overexpression. In this study, we utilized a polymeric layer-by-layer (LbL) assembly of silica-supported mesoporous titania nanoparticles (MTNst) to co-deliver paclitaxel (PTX) and microRNA 708 (miR708) for simultaneous chemotherapy and c-FLIP suppression in colorectal carcinoma. The resulting LbL miR708/PTX-MTNst showed dose-dependent cytotoxicity in HCT-116 and DLD-1 colorectal carcinoma cell lines, which was remarkably superior to that of free PTX or LbL PTX-MTNst. LbL miR708/PTX-MTNst strongly inhibited c-FLIP expression and resulted in increased expression of proapoptotic proteins. In DLD-1 xenograft tumor-bearing mice, the nanoparticles accumulated in the tumor, resulting in remarkable tumor regression, with the PTX and miR708-loaded nanoparticles showing significantly greater inhibitory effects than the free PTX or PTX-loaded nanoparticles. Immunohistochemical analyses of the tumors further confirmed the remarkable apoptotic and antiproliferative effects of the nanoparticles, whereas organ histology reinforced the biocompatibility of the system. Therefore, the LbL miR708/PTX-MTNst system, owing to its ability to deliver both chemotherapeutic drug and inhibitory miRNA to the tumor site, shows great potential to treat colorectal carcinoma in clinical settings.

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.