Cell Membrane Fragment-Wrapped Parenteral Nanoemulsions: A New Drug Delivery Tool to Target Gliomas

Poor prognosis in high-grade gliomas is mainly due to fatal relapse after surgical resection in the absence of efficient chemotherapy, which is severely hampered by the blood-brain barrier. However, the leaky blood-brain-tumour barrier forms upon tumour growth and vascularization, allowing targeted nanocarrier-mediated drug delivery. The homotypic targeting ability of cell-membrane fragments obtained from cancer cells means that these fragments can be exploited to this aim. In this experimental work, injectable nanoemulsions, which have a long history of safe clinic usage, have been wrapped in glioma-cell membrane fragments via co-extrusion to give targeted, homogeneously sized, sterile formulations. These systems were then loaded with three different chemotherapeutics, in the form of hydrophobic ion pairs that can be released into the target site thanks to interactions with physiological components. The numerous assays performed in two-dimensional (2D) and three-dimensional (3D) cell models demonstrate that the proposed approach is a versatile drug-delivery platform with chemo-tactic properties towards glioma cells, with adhesive interactions between the target cell and the cell membrane fragments most likely being responsible for the effect. This approach's promising translational perspectives towards personalized nanomedicine mean that further in vivo studies are foreseen for the future.

A New Blend of Litsea cubeba, Pinus mugo, and Cymbopogon winterianus Essential Oil Active as an Anti-tyrosinase Ingredient in Topical Formulations

Tyrosinase is a target enzyme to be inhibited in order to reduce excessive melanin production and prevent typical age-related skin disorders. Essential oils are complex mixtures of volatile compounds, belonging mainly to monoterpenoids and sesquiterpenoids, which have been relatively little studied as tyrosinase inhibitors. Among the monoterpenoids, citral (a mixture of neral and geranial) is a fragrance compound in several essential oils that has shown interesting tyrosinase inhibitory activity. Although citral is listed as an allergen among the 26 fragrances in Annex III of the Cosmetics Directive 2003/15/EC, it can be safely used for the formulation of topical products in amounts that are not expected to cause skin sensitization, as shown by various commercially available products.The aim of this work was to evaluate two different formulations (oil/water emulsion, oily solution) containing a new combination of essential oils (Litsea cubeba, Pinus mugo, Cymbopogon winterianus) applied to the skin both in nonocclusive and partially occlusive modes. The blend is designed to reduce the concentration of citral to avoid potential skin reactions while taking advantage of the inhibitory activity of citral. Specifically, the amount of citral and other bioactive compounds (myrcene, citronellal) delivered through the skin was studied as a function of formulation and mode of application.The results show that an oil/water emulsion is preferable because it releases the bioactive compounds rapidly and minimizes their evaporative loss. In addition, semi-occluded conditions are required to prevent evaporation, resulting in higher availability of the bioactive compounds in viable skin.

Discovery of a septin-4 covalent binder with antimetastatic activity in a mouse model of melanoma

Cancer spreading through metastatic processes is one of the major causes of tumour-related mortality. Metastasis is a complex phenomenon which involves multiple pathways ranging from cell metabolic alterations to changes in the biophysical phenotype of cells and tissues. In the search for new effective anti-metastatic agents, we modulated the chemical structure of the lead compound AA6, in order to find the structural determinants of activity, and to identify the cellular target responsible of the downstream anti-metastatic effects observed. New compounds synthesized were able to inhibit in vitro B16-F10 melanoma cell invasiveness, and one selected compound, CM365, showed in vivo anti-metastatic effects in a lung metastasis mouse model of melanoma. Septin-4 was identified as the most likely molecular target responsible for these effects. This study showed that CM365 is a promising molecule for metastasis prevention, remarkably effective alone or co-administered with drugs normally used in cancer therapy, such as paclitaxel.

Acellular dermal matrix imaging features in breast reconstructive surgery: a pictorial review

Acellular dermal matrices (ADMs) are biological engineered tissues, which may provide an immunologically inert scaffold in breast reconstruction. Since the literature on imaging features of ADMs is limited, radiologists must be aware of the common imaging appearances of ADM, to differentiate normal conformation from residual or recurrent disease. Our purpose is to review the current role of ADMs in implant-based breast reconstruction, describing the normal imaging findings at ultrasound, mammography, and MRI also considering the possible changes over time. In this pictorial essay, we reviewed imaging features of ADMs described in the literature and we reported our experience in patients who underwent reconstructive surgery with human or animal ADM for newly diagnosed breast cancer.

Alendronate-Grafted Nanoemulsions for Bone-Targeted Vincristine Delivery: Preliminary Studies on Cell and Animal Models

Bone is a site of distant metastases, which are a common cause of morbidity and mortality with a high socio-economic impact, for many malignant tumours. In order to engineer pharmacological therapies that are suitable for this debilitating disease, this experimental work presents injectable lipid nanoemulsions, which are endowed with a long history of safe clinical usage in parenteral nutrition, their loading with vincristine and their grafting with alendronate, with a dual purpose: merging the anticancer activity of bisphosphonates and vincristine, and enhancing bone-targeted delivery. In cell studies, alendronate synergised with the anti-migration activity of vincristine, which is important as migration plays a key role in the metastatisation process. In preliminary animal studies, carried out thanks to IVIS technology, alendronate conjugation enhanced the bone targeting of fluorescently labelled nanoemulsions. These encouraging results will drive further studies on suitable animal models of the disease.

Ultrasmall Solid-Lipid Nanoparticles via the Polysorbate Sorbitan Phase-Inversion Temperature Technique: A Promising Vehicle for Antioxidant Delivery into the Skin

Solid lipid nanoparticles promote skin hydration via stratum corneum occlusion, which prevents water loss by evaporation, and via the reinforcement of the skin's lipid-film barrier, which occurs through the adhesion of the nanoparticles to the stratum corneum. The efficacy of both phenomena correlates with lower nanoparticle size and the increased skin permeation of loaded compounds. The so-called Polysorbate Sorbitan Phase-Inversion Temperature method has, therefore, been optimized in this experimental work, in order to engineer ultrasmall solid-lipid nanoparticles that were then loaded with α-tocopherol, as the anti-age ingredient for cosmetic application. Ultrasmall solid-lipid nanoparticles have been proven to be able to favor the skin absorption of loaded compounds via the aforementioned mechanisms.

Nrf2 as a Therapeutic Target in the Resistance to Targeted Therapies in Melanoma

The use of specific inhibitors towards mutant BRAF (BRAFi) and MEK (MEKi) in BRAF-mutated patients has significantly improved progression-free and overall survival of metastatic melanoma patients. Nevertheless, half of the patients still develop resistance within the first year of therapy. Therefore, understanding the mechanisms of BRAFi/MEKi-acquired resistance has become a priority for researchers. Among others, oxidative stress-related mechanisms have emerged as a major force. The aim of this study was to evaluate the contribution of Nrf2, the master regulator of the cytoprotective and antioxidant response, in the BRAFi/MEKi acquired resistance of melanoma. Moreover, we investigated the mechanisms of its activity regulation and the possible cooperation with the oncogene YAP, which is also involved in chemoresistance. Taking advantage of established in vitro melanoma models resistant to BRAFi, MEKi, or dual resistance to BRAFi/MEKi, we demonstrated that Nrf2 was upregulated in melanoma cells resistant to targeted therapy at the post-translational level and that the deubiquitinase DUB3 participated in the control of the Nrf2 protein stability. Furthermore, we found that Nrf2 controlled the expression of YAP. Importantly, the inhibition of Nrf2, directly or through inhibition of DUB3, reverted the resistance to targeted therapies.

Surface Functionalised Parenteral Nanoemulsions for Active and Homotypic Targeting to Melanoma

Despite recent progressions in cancer genomic and immunotherapies, advanced melanoma still represents a life threat, pushing to optimise new targeted nanotechnology approaches for specific drug delivery to the tumour. To this aim, owing to their biocompatibility and favourable technological features, injectable lipid nanoemulsions were functionalised with proteins owing to two alternative approaches: transferrin was chemically grafted for active targeting, while cancer cell membrane fragments wrapping was used for homotypic targeting. In both cases, protein functionalisation was successfully achieved. Targeting efficiency was preliminarily evaluated using flow cytometry internalisation studies in two-dimensional cellular models, after fluorescence labelling of formulations with 6-coumarin. The uptake of cell-membrane-fragment-wrapped nanoemulsions was higher compared to uncoated nanoemulsions. Instead, the effect of transferrin grafting was less evident in serum-enriched medium, since such ligand probably undergoes competition with the endogenous protein. Moreover, a more pronounced internalisation was achieved when a pegylated heterodimer was employed for conjugation (p < 0.05).

Exploiting Nanomedicine for Cancer Polychemotherapy: Recent Advances and Clinical Applications

The most important limitations of chemotherapeutic agents are severe side effects and the development of multi-drug resistance. Recently, the clinical successes achieved with immunotherapy have revolutionized the treatment of several advanced-stage malignancies, but most patients do not respond and many of them develop immune-related adverse events. Loading synergistic combinations of different anti-tumor drugs in nanocarriers may enhance their efficacy and reduce life-threatening toxicities. Thereafter, nanomedicines may synergize with pharmacological, immunological, and physical combined treatments, and should be increasingly integrated in multimodal combination therapy regimens. The goal of this manuscript is to provide better understanding and key considerations for developing new combined nanomedicines and nanotheranostics. We will clarify the potential of combined nanomedicine strategies that are designed to target different steps of the cancer growth as well as its microenvironment and immunity interactions. Moreover, we will describe relevant experiments in animal models and discuss issues raised by translation in the human setting.

Parenteral Nanoemulsions Loaded with Combined Immuno- and Chemo-Therapy for Melanoma Treatment

High-grade melanoma remains a major life-threatening illness despite the improvement in therapeutic control that has been achieved by means of targeted therapies and immunotherapies in recent years. This work presents a preclinical-level test of a multi-pronged approach that includes the loading of immunotherapeutic (ICOS-Fc), targeted (sorafenib), and chemotherapeutic (temozolomide) agents within Intralipid^®, which is a biocompatible nanoemulsion with a long history of safe clinical use for total parenteral nutrition. This drug combination has been shown to inhibit tumor growth and angiogenesis with the involvement of the immune system, and a key role is played by ICOS-Fc. The inhibition of tumor growth in subcutaneous melanoma mouse models has been achieved using sub-therapeutic drug doses, which is most likely the result of the nanoemulsion's targeting properties. If translated to the human setting, this approach should therefore allow therapeutic efficacy to be achieved without increasing the risk of toxic effects.

ICOS-Fc as innovative immunomodulatory approach to counteract inflammation and organ injury in sepsis

Inducible T cell co-stimulator (ICOS), an immune checkpoint protein expressed on activated T cells and its unique ligand, ICOSL, which is expressed on antigen-presenting cells and non-hematopoietic cells, have been extensively investigated in the immune response. Recent findings showed that a soluble recombinant form of ICOS (ICOS-Fc) can act as an innovative immunomodulatory drug as both antagonist of ICOS and agonist of ICOSL, modulating cytokine release and cell migration to inflamed tissues. Although the ICOS-ICOSL pathway has been poorly investigated in the septic context, a few studies have reported that septic patients have reduced ICOS expression in whole blood and increased serum levels of osteopontin (OPN), that is another ligand of ICOSL. Thus, we investigated the pathological role of the ICOS-ICOSL axis in the context of sepsis and the potential protective effects of its immunomodulation by administering ICOS-Fc in a murine model of sepsis. Polymicrobial sepsis was induced by cecal ligation and puncture (CLP) in five-month-old male wild-type (WT) C57BL/6, ICOS-/-, ICOSL-/- and OPN-/- mice. One hour after the surgical procedure, either CLP or Sham (control) mice were randomly assigned to receive once ICOS-Fc, F119SICOS-Fc, a mutated form uncapable to bind ICOSL, or vehicle intravenously. Organs and plasma were collected 24 h after surgery for analyses. When compared to Sham mice, WT mice that underwent CLP developed within 24 h a higher clinical severity score, a reduced body temperature, an increase in plasma cytokines (TNF-α, IL-1β, IL-6, IFN-γ and IL-10), liver injury (AST and ALT) and kidney (creatinine and urea) dysfunction. Administration of ICOS-Fc to WT CLP mice reduced all of these abnormalities caused by sepsis. Similar beneficial effects were not seen in CLP-mice treated with F119SICOS-Fc. Treatment of CLP-mice with ICOS-Fc also attenuated the sepsis-induced local activation of FAK, P38 MAPK and NLRP3 inflammasome. ICOS-Fc seemed to act at both sides of the ICOS-ICOSL interaction, as the protective effect was lost in septic knockout mice for the ICOS or ICOSL genes, whereas it was maintained in OPN knockout mice. Collectively, our data show the beneficial effects of pharmacological modulation of the ICOS-ICOSL pathway in counteracting the sepsis-induced inflammation and organ dysfunction.

ICOSL Stimulation by ICOS-Fc Accelerates Cutaneous Wound Healing In Vivo

Background: ICOS and its ligand ICOSL are immune receptors whose interaction triggers bidirectional signals that modulate the immune response and tissue repair. Aim: The aim of this study was to assess the in vivo effects of ICOSL triggering by ICOS-Fc, a recombinant soluble form of ICOS, on skin wound healing. Methods: The effect of human ICOS-Fc on wound healing was assessed, in vitro, and, in vivo, by skin wound healing assay using ICOS^−/− and ICOSL^−/− knockout (KO) mice and NOD-SCID-IL2R null (NSG) mice. Results: We show that, in wild type mice, treatment with ICOS-Fc improves wound healing, promotes angiogenesis, preceded by upregulation of IL-6 and VEGF expression; increases the number of fibroblasts and T cells, whereas it reduces that of neutrophils; and increases the number of M2 vs. M1 macrophages. Fittingly, ICOS-Fc enhanced M2 macrophage migration, while it hampered that of M1 macrophages. ICOS^−/− and ICOSL^−/− KO, and NSG mice showed delayed wound healing, and treatment with ICOS-Fc improved wound closure in ICOS^−/− and NSG mice. Conclusion: These data show that the ICOS/ICOSL network cooperates in tissue repair, and that triggering of ICOSL by ICOS-Fc improves cutaneous wound healing by increasing angiogenesis and recruitment of reparative macrophages.

Dupilumab ocular side effects in patients with atopic dermatitis: a systematic review

Atopic dermatitis (AD) is a chronic, inflammatory skin disorder that most frequently occurs in children, but it can also affect adults. Even though most AD cases can be managed with topical treatments, moderate-to-severe forms require systemic therapies. Dupilumab is the first human monoclonal antibody approved for the treatment of AD. Its action is through IL-4 receptor alpha subunit inhibition, thus blocking IL-4 and IL-13 signaling pathways. It has been shown to be an effective, well tolerated therapy for AD, as well as for asthma, chronic rhinosinusitis with nasal polyposis (CRSwNP) and eosinophilic esophagitis (EoE). However, an increasing incidence of Dupilumab-induced ocular surface disease (DIOSD) has been reported in patients treated with Dupilumab, as compared to placebo. The aim of this study was to summarize scientific data regarding DIOSD in AD patients treated with Dupilumab. A search of PubMed and clinicaltrials.gov databases was performed. There was no limit to study design. All AD cases were moderate-to-severe. DIOSD was either dermatologist-, allergist-, or ophtalmologist-assessed. Evidence shows that DIOSD occurs most frequently in patients with atopic dermatitis and not in other skin conditions, neither in patients with asthma, CRSwNP, nor EoE who are on Dupilumab treatment. Further studies are warranted in order to establish a causal relationship between Dupilumab and ocular surface disease. Nevertheless, ophtalmological evaluations prior to Dupilumab initiation can benefit AD patients with previous ocular pathology or current ocular symptomatology. Also, patch testing for ocular allergic contact dermatitis might be advantageous in patients with a history of allergic conjunctivitis. Furthermore, TARC, IgE and circulating eosinophils levels might be important biomarkers for a baseline assessment of future candidates to Dupilumab treatment. However, TARC measurements should be resumed for research purposes only.

Inducible T-Cell Costimulator Ligand Plays a Dual Role in Melanoma Metastasis upon Binding to Osteopontin or Inducible T-Cell Costimulator

Recently, we demonstrated that inducible T-cell costimulator (ICOS) shares its unique ligand (ICOSL) with osteopontin (OPN), and OPN/ICOSL binding promotes tumor metastasis and angiogenesis in the 4T1 breast cancer model. Literature showed that OPN promotes melanoma metastasis by suppressing T-cell activation and recruiting myeloid suppressor cells (MDSC). On the opposite, ICOS/ICOSL interaction usually sustains an antitumor response. Here, we engineered murine B16F10 melanoma cells, by transfecting or silencing ICOSL. In vitro data showed that loss of ICOSL favors anchorage-independent growth and induces more metastases in vivo, compared to ICOSL expressing cells. To dissect individual roles of the three molecules, we compared data from C57BL/6 with those from OPN-KO, ICOS-KO, and ICOSL-KO mice, missing one partner at a time. We found that OPN produced by the tumor microenvironment (TME) favors the metastasis by interacting with stromal ICOSL. This activity is dominantly inhibited by ICOS expressed on TME by promoting Treg expansion. Importantly, we also show that OPN and ICOSL highly interact in human melanoma metastases compared to primary tumors. Interfering with this binding may be explored in immunotherapy either for nonresponding or patients resistant to conventional therapies.

Inducible T-cell co-stimulator (ICOS) and ICOS ligand are novel players in the multiple-myeloma microenvironment

The inducible T-cell co-stimulator (ICOS) is a T-cell receptor that, once bound to ICOS ligand (ICOSL) expressed on several cell types including the B-cell lineage, plays a decisive role in adaptive immunity by regulating the interplay between B and T cells. In addition to its immunomodulatory functions, we have shown that ICOS/ICOSL signalling can inhibit the activity of osteoclasts, unveiling a novel mechanism of lymphocyte-bone cells interactions. ICOS and ICOSL can also be found as soluble forms, namely sICOS and sICOSL. Here we show that: (i) levels of sICOS and sICOSL are increased in multiple myeloma (MM) compared to monoclonal gammopathy of undetermined significance and smouldering MM; (ii) levels of sICOS and sICOSL variably correlate with several markers of tumour burden; and (iii) sICOS levels tend to be higher in Durie-Salmon stage II/III versus stage I MM and correlate with overall survival as an independent variable. Moreover, surface ICOS and ICOSL are expressed in both myeloma cells and normal plasma cells, where they probably regulate different functional stages. Finally, ICOSL triggering inhibits the migration of myeloma cell lines in vitro and the growth of ICOSL⁺ MOPC-21 myeloma cells in vivo. These results suggest that ICOS and ICOSL represent novel markers and therapeutic targets for MM.

Nanotechnology Addressing Cutaneous Melanoma: The Italian Landscape

Cutaneous melanoma is one of the most aggressive solid tumors, with a low survival for the metastatic stage. Currently, clinical melanoma treatments include surgery, chemotherapy, targeted therapy, immunotherapy and radiotherapy. Of note, innovative therapeutic regimens concern the administration of multitarget drugs in tandem, in order to improve therapeutic efficacy. However, also, if this drug combination is clinically relevant, the patient's response is not yet optimal. In this scenario, nanotechnology-based delivery systems can play a crucial role in the clinical treatment of advanced melanoma. In fact, their nano-features enable targeted drug delivery at a cellular level by overcoming biological barriers. Various nanomedicines have been proposed for the treatment of cutaneous melanoma, and a relevant number of them are undergoing clinical trials. In Italy, researchers are focusing on the pharmaceutical development of nanoformulations for malignant melanoma therapy. The present review reports an overview of the main melanoma-addressed nanomedicines currently under study in Italy, alongside the state of the art of melanoma therapy. Moreover, the latest Italian advances concerning the pre-clinical evaluation of nanomedicines for melanoma are described.

Post-translational down-regulation of Nrf2 and YAP proteins, by targeting deubiquitinases, reduces growth and chemoresistance in pancreatic cancer cells

The intrinsic chemoresistance of pancreatic ductal adenocarcinoma (PDAC) represents the main obstacle in treating this aggressive malignancy. It has been observed that high antioxidant levels and upregulated Nrf2 and the YAP protein expression can be involved in PDAC chemoresistance. The mechanisms of Nrf2 and YAP increase need to be clarified. We chose a panel of PDAC cell lines with diverse sensitivity to cisplatin and gemcitabine. In PANC-1 chemoresistant cells, we found a low level of oxidative stress and high levels of Nrf2 and YAP protein expressions and their respective targets. On the contrary, in CFPAC-1 chemosensitive cells, we found high levels of oxidative stress and low level of these two proteins, as well as their respective targets. In MiaPaCa-2 cells with a middle chemoresistance, we observed intermediate features. When Nrf2 and YAP were inhibited in PANC-1 cells by Ailanthone, a plant extract, we observed a reduction of viability, thus sustaining the role of these two proteins in maintaining the PDAC chemoresistance. We then delved into the mechanisms of the Nrf2 and YAP protein upregulation in chemoresistance, discovering that it was at a post-translational level since the mRNA expressions did not match the protein levels. Treatments of PANC-1 cells with the proteasome inhibitor MG-132 and the protein synthesis inhibitor cycloheximide further confirmed this observation. The expression of DUB3 and OTUD1 deubiquitinases, involved in the control of Nrf2 and YAP protein level, respectively, was also investigated. Both protein expressions were higher in PANC-1 cells, intermediate in MiaPaCa-2 cells, and lower in CFPAC-1 cells. When DUB3 or OTUD1 were silenced, both Nrf2 and YAP expressions were downregulated. Importantly, in deubiquitinase-silenced cells, we observed a great reduction of proliferation and a higher sensitivity to gemcitabine treatment, suggesting that DUB3 and OTUD1 can represent a suitable target to overcome chemoresistance in PDAC cells.

Control of Oxidative Stress in Cancer Chemoresistance: Spotlight on Nrf2 Role

Chemoresistance represents the main obstacle to cancer treatment with both conventional and targeted therapy. Beyond specific molecular alterations, which can lead to targeted therapy, metabolic remodeling, including the control of redox status, plays an important role in cancer cell survival following therapy. Although cancer cells generally have a high basal reactive oxygen species (ROS) level, which makes them more susceptible than normal cells to a further increase of ROS, chemoresistant cancer cells become highly adapted to intrinsic or drug-induced oxidative stress by upregulating their antioxidant systems. The antioxidant response is principally mediated by the transcription factor Nrf2, which has been considered the master regulator of antioxidant and cytoprotective genes. Nrf2 expression is often increased in several types of chemoresistant cancer cells, and its expression is mediated by diverse mechanisms. In addition to Nrf2, other transcription factors and transcriptional coactivators can participate to maintain the high antioxidant levels in chemo and radio-resistant cancer cells. The control of expression and function of these molecules has been recently deepened to identify which of these could be used as a new therapeutic target in the treatment of tumors resistant to conventional therapy. In this review, we report the more recent advances in the study of Nrf2 regulation in chemoresistant cancers and the role played by other transcription factors and transcriptional coactivators in the control of antioxidant responses in chemoresistant cancer cells.

Albumin nanoformulations as an innovative solution to overcome doxorubicin chemoresistance

Aim: Resistance to chemotherapy is a major limiting factor that hamper the effectiveness of anticancer therapies. Doxorubicin is an antineoplastic agent used in the treatment of a wide range of cancers. However, it presents several limitations such as dose-dependent cardiotoxicity, lack of selectivity for tumor cells, and induced cell resistance. Nanotechnology represents a promising strategy to avoid these drawbacks. In this work, new albumin-based nanoparticles were formulated for the intracellular delivery of doxorubicin with the aim to overcome cancer drug resistance.

Methods: Glycol chitosan-coated and uncoated albumin nanoparticles were prepared with a tuned coacervation method. The nanoformulations were in vitro characterized evaluating the physicochemical parameters, morphology, and in vitro release kinetics. Biological assays were performed on A2780res and EMT6 cells from human ovarian carcinoma and mouse mammary cell lines resistant for doxorubicin, respectively.

Results: Cell viability assays showed that nanoparticles have higher cytotoxicity than the free drug. Moreover, at low concentrations, both doxorubicin-loaded nanoparticles inhibited the cell colony formation in a greater extent than drug solution. In addition, the cell uptake of the different formulations was investigated by confocal microscopy and by the HPLC determination of doxorubicin intracellular accumulation. The nanoparticles were rapidly internalized in greater extent compared to the free drug.

Conclusion: Based on these results, doxorubicin-loaded albumin nanoparticles might represent a novel platform to overcome the mechanism of drug resistance in cancer cell lines and improve the drug efficacy.

Sr-Containing Mesoporous Bioactive Glasses Bio-Functionalized with Recombinant ICOS-Fc: An In Vitro Study

Osteoporotic bone fractures represent a critical clinical issue and require personalized and specific treatments in order to stimulate compromised bone tissue regeneration. In this clinical context, the development of smart nano-biomaterials able to synergistically combine chemical and biological cues to exert specific therapeutic effects (i.e., pro-osteogenic, anti-clastogenic) can allow the design of effective medical solutions. With this aim, in this work, strontium-containing mesoporous bioactive glasses (MBGs) were bio-functionalized with ICOS-Fc, a molecule able to reversibly inhibit osteoclast activity by binding the respective ligand (ICOS-L) and to induce a decrease of bone resorption activity. N₂ adsorption analysis and FT-IR spectroscopy were used to assess the successful grafting of ICOS-Fc on the surface of Sr-containing MBGs, which were also proved to retain the peculiar ability to release osteogenic strontium ions and an excellent bioactivity after functionalization. An ELISA-like assay allowed to confirm that grafted ICOS-Fc molecules were able to bind ICOS-L (the ICOS binding ligand) and to investigate the stability of the amide binding to hydrolysis in aqueous environment up to 21 days. In analogy to the free form of the molecule, the inhibitory effect of grafted ICOS-Fc on cell migratory activity was demonstrated by using ICOSL positive cell lines and the ability to inhibit osteoclast differentiation and function was confirmed by monitoring the differentiation of monocyte-derived osteoclasts (MDOCs), which revealed a strong inhibitory effect, also proven by the downregulation of osteoclast differentiation genes. The obtained results showed that the combination of ICOS-Fc with the intrinsic properties of Sr-containing MBGs represents a very promising approach to design personalized solutions for patients affected by compromised bone remodeling (i.e., osteoporosis fractures).

Nanoemulsions as Delivery Systems for Poly-Chemotherapy Aiming at Melanoma Treatment

Aims: Advanced melanoma is characterized by poor outcome. Despite the number of treatments having been increased over the last decade, current pharmacological strategies are only partially effective. Therefore, the improvement of the current systemic therapy is worthy of investigation. Methods: a nanotechnology-based poly-chemotherapy was tested at preclinical level. Temozolomide, rapamycin, and bevacizumab were co-loaded as injectable nanoemulsions for total parenteral nutrition (Intralipid^®), due to suitable devices, and preliminarily tested in vitro on human and mouse cell models and in vivo on the B16-F10 melanoma mouse model. Results: Drug combination was efficiently loaded in the liquid lipid matrix of Intralipid^®, including bevacizumab monoclonal antibody, leading to a fast internalization in tumour cells. An increased cytotoxicity towards melanoma cells, as well as an improved inhibition of tumour relapse, migration, and angiogenesis were demonstrated in cell models for the Intralipid^®-loaded drug combinations. In preliminary in vivo studies, the proposed approach was able to reduce tumour growth significantly, compared to controls. A relevant efficacy towards tumour angiogenesis and mitotic index was determined and immune response was involved. Conclusions: In these preliminary studies, Intralipid^® proved to be a safe and versatile poly-chemotherapy delivery system for advanced melanoma treatment, by acting on multiple mechanisms.

Ailanthone increases oxidative stress in CDDP-resistant ovarian and bladder cancer cells by inhibiting of Nrf2 and YAP expression through a post-translational mechanism

Chemoresistance represents one of the main obstacles in treating several types of cancer, including bladder and ovarian cancers, and it is characterized by an increase of cellular antioxidant potential. Nrf2 and YAP proteins play an important role in increasing chemoresistance and in inducing antioxidant enzymes. It has been reported that Ailanthone (Aila), a compound extracted from the Ailanthus Altissima, has an anticancer activity toward several cancer cell lines, including chemoresistant cell lines. We have examined the effect of Aila on proliferation, migration and expression of Nrf2 and YAP proteins in A2780 (CDDP-sensitive) and A2780/CP70 (CDDP-resistant) ovarian cancer cells. Furthermore, to clarify the mechanism of Aila action we extended our studies to sensitive and CDDP-resistant 253J-BV bladder cancer cells, which have been used in a previous study on the effect of Aila. Results demonstrated that Aila exerted an inhibitory effect on growth and colony formation of sensitive and CDDP-resistant ovarian cancer cells and reduced oriented cell migration with higher effectiveness in CDDP resistant cells. Moreover, Aila strongly reduced Nrf2 and YAP protein expression and reduced the expression of the Nrf2 target GSTA4, and the YAP/TEAD target survivin. In CDDP-resistant ovarian and bladder cancer cells the intracellular oxidative stress level was lower with respect to the sensitive cells. Moreover, Aila treatment further reduced the superoxide anion content of CDDP-resistant cells in correlation with the reduction of Nrf2 and YAP proteins. However, Aila treatment increased Nrf2 and YAP mRNA expression in all cancer cell lines. The inhibition of proteolysis by MG132, a proteasoma inhibitor, restored Nrf2 and YAP protein expressions, suggesting that the Aila effect was at post-translational level. In accordance with this observation, we found an increase of the Nrf2 inhibitor Keap1, a reduction of p62/SQSTM1, a Nrf2 target which leads Keap1 protein to the autophagic degradation, and a reduction of P-YAP. Moreover, UCHL1 deubiquitinase expression, which was increased in bladder and ovarian resistant cells, was down-regulated by Aila treatment. In conclusion we demonstrated that Aila can reduce proliferation and migration of cancer cells through a mechanism involving a post translational reduction of Nrf2 and YAP proteins which, in turn, entailed an increase of oxidative stress particularly in the chemoresistant lines.

Immunotherapy of experimental melanoma with ICOS-Fc loaded in biocompatible and biodegradable nanoparticles

Inducible T-cell costimulator (ICOS) upon binding to its ligand (ICOSL) mediates adaptive immunity and antitumor response. Thus, antitumor therapies targeting the ICOS/ICOSL pathway hold great promise for cancer treatment. In this regard, ICOSL triggering by a soluble recombinant form of ICOS (ICOS-Fc) hampered adhesiveness and migration of dendritic, endothelial, and tumor cells in vitro. Furthermore, in vivo treatment with ICOS-Fc previously showed the capability to inhibit lung metastatization of ICOSL⁺ B16-F10 melanoma cells when injected intravenously in mice, but it failed to block the growth of established subcutaneous B16-F10 murine tumors. Thus, we asked whether passive targeting of solid tumors with ICOS-Fc-loaded biocompatible and biodegradable nanoparticles (NPs) could instead prove effectiveness in reducing tumor growth. Here, ICOS-Fc was loaded in two types of polymer nanoparticles, i.e. cross-linked β-cyclodextrin nanosponges (CDNS) and poly(lactic-co-glycolic acid) (PLGA) NPs and in vitro characterized. In vivo experiments showed that treatment of C57BL6/J mice with ICOS-Fc loaded into the two nanoformulations inhibits the growth of established subcutaneous B16-F10 tumors. This anticancer activity appears to involve both anti-angiogenic and immunoregulatory effects, as shown by decreased tumor vascularization and downmodulation of IL-10 and Foxp3, two markers of regulatory T cells (Tregs). Overall, the substantial in vivo anticancer activity of ICOS-Fc-loaded CDNS and PLGA NPs against different components of the tumor microenvironment makes these nanoformulations attractive candidates for future combination cancer therapy.

Study of oxyresveratrol complexes with insoluble cyclodextrin based nanosponges: Developing a novel way to obtain their complexation constants and application in an anticancer study

The complexation of the bioactive compound oxyresveratrol (OXY) with a polymer called cyclodextrin-based nanosponge (CD-NS) and its application was studied.A new methodology is used to calculate, an apparent inclusion complex constant (K_Fapp) between a ligand and CD-NSs. Moreover, the K_Fapp of resveratrol was also evaluated and compared. The complex of OXY with the nanosponge β-CDI 1:4, was studied in vitro using DSC, TGA and FTIR techniques and its drug loading and release behavior were studied. An in vitro digestion showed higher protection of OXY complexed than free OXY. The bioactivity enhancing capacity of OXY was also studied against prostate (PC-3) and colon (HT-29 and HCT-116) cancer cell lines, where it showed stronger cell viability inhibition than the free drug. The findings as a whole represent a new opportunity for studying the complexation of drugs in CD-NSs and the use of oxyresveratrol as an ingredient in nutraceutical products.

Magnetic resonance enterography

Crohn's disease is a condition of chronic inflammation that may involve any part of the gastrointestinal tract, although it more frequently affects the terminal ileum. Longstanding inflammation may lead to several bowel complications including obstruction, stricture, fistula and abscesses which often necessitate surgery. Cross-sectional imaging methods such as computed tomography and magnetic resonance imaging are being utilized more frequently to assess mural and extramural inflammatory bowel disease manifestations. Magnetic resonance enterography (MRE) for assessment of small bowel is optimal because of absence of ionizing radiation, better soft tissue contrast, development of motion-free sequences and high resolution images. A typical protocol includes pre and postcontrast sequences utilizing an enteric contrast agent for adequate bowel distention and an antiperistaltic agent. Overall, MRE allows the evaluation of disease activity, extraenteric complication and response to therapy with a great impact on patient management. In this review we discuss the features of MRE from patient's preparation and exam protocol to pathological findings.

Post-translational inhibition of YAP oncogene expression by 4-hydroxynonenal in bladder cancer cells

The transcriptional regulator YAP plays an important role in cancer progression and is negatively controlled by the Hippo pathway. YAP is frequently overexpressed in human cancers, including bladder cancer. Interestingly, YAP expression and activity can be inhibited by pro-oxidant conditions; moreover, YAP itself can also affect the cellular redox status through multiple mechanisms. 4-Hydroxynonenal (HNE), the most intensively studied end product of lipid peroxidation, is a pro-oxidant agent able to deplete GSH and has an anti-tumoral effect by affecting multiple signal pathways, including the down-regulation of oncogene expressions. These observations prompted us to investigate the effect of HNE on YAP expression and activity. We demonstrated that HNE inhibited YAP expression and its target genes in bladder cancer cells through a redox-dependent mechanism. Moreover, the YAP down-regulation was accompanied by an inhibition of proliferation, migration, invasion, and angiogenesis, as well as by an accumulation of cells in the G2/M phase of cell cycle and by an induction of apoptosis. We also established the YAP role in inhibiting cell viability and inducing apoptosis in HNE-treated cells by using an expression vector for YAP. Furthermore, we identified a post-translational mechanism for the HNE-induced YAP expression inhibition, involving an increase of YAP phosphorylation and ubiquitination, leading to proteasomal degradation. Our data established that HNE can post-translationally down-regulate YAP through a redox-dependent mechanism and that this modulation can contribute to determining the specific anti-cancer effects of HNE.

Evaluation of solubility enhancement, antioxidant activity, and cytotoxicity studies of kynurenic acid loaded cyclodextrin nanosponge

Kynurenic acid demonstrates antioxidant, neuroprotective and free radical scavenging properties. However, low aqueous solubility of kynurenic acid limits its therapeutic activity. In the present study, cyclodextrin nanosponges were used to improve the solubility and therapeutic activity of kynurenic acid. The formation of kynurenic acid loaded nanosponge was confirmed by different characterization techniques. The solubility of kynurenic acid was significantly increased with nanosponge (111.1 μg/ml) compared to free kynurenic acid (16.4 μg/ml) and β-cyclodextrin (28.6 μg/ml). High drug loading (19.06%) and encapsulation efficiency (95.31%) were achieved with NS. The particle size and zeta potential of kynurenic acid loaded nanosponge was around 255.8 nm and -23 mV respectively. Moreover, higher solubilization of kynurenic acid loaded nanosponge produced better antioxidant activity compared to free kynurenic acid. The kynurenic acid loaded nanosponge and blank nanosponge were found nontoxic in the cytotoxicity assay. Thus, these studies demonstrated that nanosponges can be used as a carrier for the delivery of kynurenic acid.

Paclitaxel-Loaded Nanosponges Inhibit Growth and Angiogenesis in Melanoma Cell Models

This study investigated the effects of free paclitaxel (PTX) and PTX-loaded in pyromellitic nanosponges (PTX-PNS) in reducing in vitro and in vivo melanoma cell growth and invasivity, and in inhibiting angiogenesis. To test the response of cells to the two PTX formulations, the cell viability was evaluated by MTT assay in seven continuous cell lines, in primary melanoma cells, both in 2D and 3D cultures, and in human umbilical vein endothelial cells (HUVECs) after exposure to different concentrations of PTX or PTX-PNS. Cell motility was assessed by a scratch assay or Boyden chamber assay, evaluating cell migration in presence or absence of diverse concentrations of PTX or PTX-PNS. The effect of PTX and PTX-PNS on angiogenesis was evaluated as endothelial tube formation assay, a test able to estimate the formation of three-dimensional vessels in vitro. To assess the anticancer effect of PTX and PTX-PNS in in vivo experiments, the two drug formulations were tested in a melanoma mouse model obtained by B16-BL6 cell implantation in C57/BL6 mice. Results obtained were as follows: 1) MTT analysis revealed that cell proliferation was more affected by PTX-PNS than by PTX in all tested cell lines, in both 2D and 3D cultures; 2) the analysis of the cell migration showed that PTX-PNS acted at very lower concentrations than PTX; 3) tube formation assay showed that PTX-PNS were more effective in inhibiting tube formation than free PTX; and 4) in vivo experiments demonstrated that tumor weights, volumes, and growth were significantly reduced by PTX-PNS treatment with respect to PTX; the angiogenesis and the cell proliferation, detected in the tumor samples with CD31 and Ki-67 antibodies, respectively, indicated that, in the PTX-PNS-treated tumors, the tube formation was inhibited, and a low amount of proliferating cells was present. Taken together, our data demonstrated that our new PTX nanoformulation can respond to some important issues related to PTX treatment, lowering the anti-tumor effective doses and increasing the effectiveness in inhibiting melanoma growth in vivo.

Low-dose curcuminoid-loaded in dextran nanobubbles can prevent metastatic spreading in prostate cancer cells

Preventing recurrences and metastasis of prostate cancer after prostatectomy by administering adjuvant therapies is quite a controversial issue. In addition to effectiveness, absence of side effects and long term toxicity are mandatory. Curcuminoids (Curc) extracted with innovative techniques and effectively loaded by polymeric nanobubbles (Curc-NBs) satisfy such requirements. Curc-NBs showed stable over 30 d, were effectively internalized by tumor cells and were able to slowly release Curc in a sustained way. Significant biological effects were detected in PC-3 and DU-145 cell lines where Curc-NBs were able to inhibit adhesion and migration, to promote cell apoptosis and to affect cell viability and colony-forming capacity in a dose-dependent manner. Since the favourable effects are already detectable at very low doses, which can be reached at a clinical level, the actual drug concentration can be visualized and monitored by US or MRI, Curc-NBs can be proposed as an effective adjuvant theranostic tool.

Untangling Extracellular Proteasome-Osteopontin Circuit Dynamics in Multiple Sclerosis

The function of proteasomes in extracellular space is still largely unknown. The extracellular proteasome-osteopontin circuit has recently been hypothesized to be part of the inflammatory machinery regulating relapse/remission phase alternation in multiple sclerosis. However, it is still unclear what dynamics there are between the different elements of the circuit, what the role of proteasome isoforms is, and whether these inflammatory circuit dynamics are associated with the clinical severity of multiple sclerosis. To shed light on these aspects of this novel inflammatory circuit, we integrated in vitro proteasome isoform data, cell chemotaxis cell culture data, and clinical data of multiple sclerosis cohorts in a coherent computational inference framework. Thereby, we modeled extracellular osteopontin-proteasome circuit dynamics during relapse/remission alternation in multiple sclerosis. Applying this computational framework to a longitudinal study on single multiple sclerosis patients suggests a complex interaction between extracellular proteasome isoforms and osteopontin with potential clinical implications.

Ailanthone inhibits cell growth and migration of cisplatin resistant bladder cancer cells through down-regulation of Nrf2, YAP, and c-Myc expression

BACKGROUND

Ailanthone (Aila) is a natural active compound isolated from the Ailanthus altissima, which has been shown to possess an "in vitro" growth-inhibitory effect against several cancer cell lines. Advanced bladder cancer is a common disease characterized by a frequent onset of resistance to cisplatin-based therapy. The cisplatin (CDDP) resistance is accompanied by an increase in Nrf2 protein expression which contributes to conferring resistance. Recently, we demonstrated a cross-talk between Nrf2 and YAP. YAP has also been demonstrated to play an important role in chemoresistance of bladder cancer.

PURPOSE

We analyzed the antitumor effect of Aila in sensitive and CDDP-resistant bladder cancer cells and the molecular mechanisms involved in Aila activity.

STUDY DESIGN

Sensitive and CDDP-resistant 253J B-V and 253J bladder cancer cells, intrinsically CDDP-resistant T24 bladder cancer cells and HK-2 human renal cortex cells were used. Cells were treated with diverse concentrations of Aila and proliferation, cell cycle, apoptosis and gene expressions were determined.

METHODS

Aila toxicity and proliferation were determined by MTT and colony forming methods, respectively. Cell cycle was determined by cytofluorimetric analysis through PI staining method. Apoptosis was detected using Annexin V and PI double staining followed by quantitative flow cytometry. Expressions of Nrf2, Yap, c-Myc, and house-keeping genes were determined by western blot with specific antibodies. Cell migration was detected by wound healing and Boyden chamber analysis.

RESULTS

Aila inhibited the growth of sensitive and CDDP-resistant bladder cancer cells with the same effectiveness. On the contrary, the growth of HK-2 cells was only slightly reduced by Aila. Cell cycle analysis revealed an accumulation of Aila-treated bladder cancer cells in the G0/G1 phase. Interestingly, Aila strongly reduced Nrf2 expression in these cell lines. Moreover, Aila significantly reduced YAP, and c-Myc protein expression. The random and the oriented migration of bladder cancer cells were strongly inhibited by Aila treatment, in particular in CDDP-resistant cells.

CONCLUSION

Aila inhibited proliferation and invasiveness of bladder cancer cells. Its high effectiveness in CDDP resistant cells could be related to the inhibition of Nrf2, YAP, and c-Myc expressions. Aila could represent a new tool to treating CDDP-resistant bladder cancers.

Stearoyl-Chitosan Coated Nanoparticles Obtained by Microemulsion Cold Dilution Technique

Chitosan is an excipient which has been studied thoroughly in research works thanks to its positive characteristics such as muco-adhesiveness and ability to open epithelial-tight-junctions. In this article, lipophilic stearoyl chitosan (ST-CS) was synthetized in order to anchor this polymer to lipid nanoparticles and prepare ST-CS-coated nanoparticles (ST-CS-NP) using the microemulsion cold dilution technique. Curcumin (CURC) was used as model drug. CURC-ST-CS-NP were characterized by dimensional analysis, zeta potential, drug entrapment, drug release; tested in vitro on Human Umbilical Vein Endothelial Cell (HUVEC) cells to study its cytotoxicity and on human pancreatic cancer cells (PANC-1) to determine inhibition ability; tested in rats to determine CURC blood profiles and biodistribution. CURC-ST-CS-NP had mean diameters in the range 200–400 nm and CURC entrapment up to 73%. These systems did not show cytotoxicity on HUVEC cells at all tested dilutions and revealed to be more effective than free CURC solution on PANC-1 cells at 5 and 10 µM CURC. Blood profile studies evidenced as CURC entrapment in NP prolonged the permanence of drug in the systemic circulation compared to CURC solution due to a certain stealth property of NP, probably attributable to hydrophilic chitosan coating. Biodistribution studies showed a smaller CURC concentration in RES organs when CURC-ST-CS-NP were administered.

Glutathione/pH-responsive nanosponges enhance strigolactone delivery to prostate cancer cells

Strigolactones (SLs) are carotenoid-derived plant hormones that exhibit anti-cancer activities. We previously demonstrated that two SL analogues, MEB55 and ST362, inhibit the growth and survival of various cancer cell lines. However, these compounds have low aqueous solubility and stability at physiological pH. Here, we generated SL-loaded glutathione/pH-responsive nanosponges (GSH/pH-NS) to selectively deliver SLs to prostate cancer cells and enhance their therapeutic efficacy. The SLs were readily incorporated into the GSH/pH-NS. The drug loading efficiency was 13.9% for MEB55 and 15.4% for ST362, and the encapsulation efficiency was 88.7% and 96.5%, respectively. Kinetic analysis revealed that release of MEB55 and ST362 from the GSH/pH-NS was accelerated at acidic pH and in the presence of a high GSH concentration. Evaluation of the effects of MEB55- and ST362-loaded GSH/pH-NS on the growth of DU145 (high GSH) and PC-3 (low GSH) prostate cancer cells revealed that the GSH/pH-NS inhibited the proliferation of DU145 cells to a greater extent than free MEB55 or ST362 over a range of concentrations. These findings indicate GSH/pH-NS are efficient tools for controlled delivery of SLs to prostate cancer cells and may enhance the therapeutic efficacy of these compounds.

α-ketoglutarate dehydrogenase inhibition counteracts breast cancer-associated lung metastasis

Metastasis formation requires active energy production and is regulated at multiple levels by mitochondrial metabolism. The hyperactive metabolism of cancer cells supports their extreme adaptability and plasticity and facilitates resistance to common anticancer therapies. In spite the potential relevance of a metastasis metabolic control therapy, so far, limited experience is available in this direction. Here, we evaluated the effect of the recently described α-ketoglutarate dehydrogenase (KGDH) inhibitor, (S)-2-[(2,6-dichlorobenzoyl) amino] succinic acid (AA6), in an orthotopic mouse model of breast cancer 4T1 and in other human breast cancer cell lines. In all conditions, AA6 altered Krebs cycle causing intracellular α-ketoglutarate (α-KG) accumulation. Consequently, the activity of the α-KG-dependent epigenetic enzymes, including the DNA demethylation ten-eleven translocation translocation hydroxylases (TETs), was increased. In mice, AA6 injection reduced metastasis formation and increased 5hmC levels in primary tumours. Moreover, in vitro and in vivo treatment with AA6 determined an α-KG accumulation paralleled by an enhanced production of nitric oxide (NO). This epigenetically remodelled metabolic environment efficiently counteracted the initiating steps of tumour invasion inhibiting the epithelial-to-mesenchymal transition (EMT). Mechanistically, AA6 treatment could be linked to upregulation of the NO-sensitive anti-metastatic miRNA 200 family and down-modulation of EMT-associated transcription factor Zeb1 and its CtBP1 cofactor. This scenario led to a decrease of the matrix metalloproteinase 3 (MMP3) and to an impairment of 4T1 aggressiveness. Overall, our data suggest that AA6 determines an α-KG-dependent epigenetic regulation of the TET-miR200-Zeb1/CtBP1-MMP3 axis providing an anti-metastatic effect in a mouse model of breast cancer-associated metastasis.

Cyclic nigerosyl-1,6-nigerose-based nanosponges: An innovative pH and time-controlled nanocarrier for improving cancer treatment

The design and structural optimisation of a novel polysaccharide-based nanomaterial for the controlled and sustained release of doxorubicin are here reported. A cross-linked polymer was obtained by reacting a tetraglucose, named cyclic nigerosyl-1-6-nigerose (CNN), with pyromellitic dianhydride. The cross-linking reaction formed solid nanoparticles, named nanosponges, able to swell as a function of the pH. Nanoparticle sizes were reduced using High Pressure Homogenization, to obtain uniform nanosuspensions. Doxorubicin was incorporated into the CNN-nanosponges in a good extent. DSC and solid state NMR analyses proved the drug interaction with the polymer matrix. In vitro studies demonstrated pH-dependent slow and prolonged release kinetics of the drug from the nanoformulation. Doxorubicin-loaded CNN-nanosponges were easily internalized in A2780 cell line. They might considered an intracellular doxorubicin reservoir, able to slowly release the drug over time. CNN-nanosponges may be promising biocompatible nanocarriers for the sustained delivery of doxorubicin with potential localised application in cancer treatments.

Drug Delivery Nanoparticles in Treating Chemoresistant Tumor Cells

Intrinsic or acquired chemoresistance represents the main obstacle to the successful treatment of cancer patients. Several mechanisms are involved in multidrug resistance: decreased uptake of hydrophilic drugs, increase of energy dependent efflux, alteration of the redox state, alteration of apoptotic pathways, and modification of the tumor microenvironment. In recent years, several types of nanoparticles have been developed to overcome these obstacles and improve the accumulation and release of drugs at the pathological site. In this review, we describe the main mechanisms involved in multidrug resistance and the nanovehicles which have been proposed to target specific aspects of this phenomenon.

Crosstalk between Nrf2 and YAP contributes to maintaining the antioxidant potential and chemoresistance in bladder cancer

Redox adaptation plays an important role in cancer cells drug resistance. The antioxidant response is principally mediated by the transcription factor Nrf2, that induces the transcriptional activation of several genes involved in GSH synthesis, chemoresistance, and cytoprotection. YAP is emerging as a key mediator of chemoresistance in a variety of cancers, but its role in controlling the antioxidant status of the cells is yet elusive. Here, we show that impairing YAP protein expression reduced GSH content and Nrf2 protein and mRNA expression in bladder cancer cells. Moreover, in YAP knocked down cells the expression of FOXM1, a transcription factor involved in Nrf2 transcription, was down-regulated and the silencing of FOXM1 reduced Nrf2 expression. On the other hand, the silencing of Nrf2, as well as the depletion of GSH by BSO treatment, inhibited YAP expression, suggesting that cross-talk exists between YAP and Nrf2 proteins. Importantly, we found that silencing either YAP or Nrf2 enhanced sensitivity of bladder cancer cells to cytotoxic agents and reduced their migration. Furthermore, the inhibition of both YAP and Nrf2 expressions significantly increased cytotoxic drug sensitivity and synergistically reduced the migration of chemoresistant bladder cancer cells. These findings provide a rationale for targeting these transcriptional regulators in patients with chemoresistant bladder cancer, expressing high YAP and bearing a proficient antioxidant system.

Solid Lipid Nanoparticles Carrying Temozolomide for Melanoma Treatment. Preliminary In Vitro and In Vivo Studies

AIM

To develop an innovative delivery system for temozolomide (TMZ) in solid lipid nanoparticles (SLN), which has been preliminarily investigated for the treatment of melanoma.

MATERIALS AND METHODS

SLN-TMZ was obtained through fatty acid coacervation. Its pharmacological effects were assessed and compared with free TMZ in in vitro and in vivo models of melanoma and glioblastoma.

RESULTS

Compared to the standard free TMZ, SLN-TMZ exerted larger effects, when cell proliferation of melanoma cells, and neoangiogeneis were evaluated. SLN-TMZ also inhibited growth and vascularization of B16-F10 melanoma in C57/BL6 mice, without apparent toxic effects.

CONCLUSION

SLN could be a promising strategy for the delivery of TMZ, allowing an increased stability of the drug and thereby its employment in the treatment of aggressive malignacies.

Lipophilic Prodrug of Floxuridine Loaded into Solid Lipid Nanoparticles: In Vitro Cytotoxicity Studies on Different Human Cancer Cell Lines

Floxuridine is a very effective drug with high potency in the treatment of various tumors but its utility is limited by its low efficiency of cellular uptake. In order to improve the floxuridine efficiency of cellular uptake, lipophilic prodrug of floxuridine (3',5'-distearoyl-5-fluoro-2'-deoxyuridine) was synthetized and loaded into behenic acid nanoparticles produced by fatty acid coacervation technique. Generally, spherical shaped SLN with mean diameters below 300 nm were obtained. Distearoyl-floxuridine was loaded in SLN with high entrapment efficiency (from 70.8 to 82.8%). In Vitro cytotoxicity studies on different human cancer cell lines (M14, HT-29 and MDA-MB231) were performed in order to test the ability of distearoyl-floxuridine-SLN to inhibit the cancer cell growth. In MTT test distearoyl floxuridine SLN showed a greater efficacy than floxuridine on all cancer cell lines revealing an efficiency about 100 times higher. Also clonogenic assay showed a higher cytotoxicity of distearoyl-floxuridine-SLN compared to floxuridine but the difference between the formulations was only about 10 times. In conclusion, SLN proved to be a promising vehicle to increase the floxuridine efficacy in cancer therapy.

Enhanced cytotoxic effect of camptothecin nanosponges in anaplastic thyroid cancer cells in vitro and in vivo on orthotopic xenograft tumors

Anaplastic carcinoma of the thyroid (ATC) is a lethal human malignant cancer with median survival of 6 months. To date, no treatment has substantially changed its course, which makes urgent need for the development of novel drugs or novel formulations for drug delivery. Nanomedicine has enormous potential to improve the accuracy of cancer therapy by enhancing availability and stability, decreasing effective doses and reducing side effects of drugs. Camptothecin (CPT) is an inhibitor of DNA topoisomerase-I with several anticancer properties but has poor solubility and a high degradation rate. Previously, we reported that CPT encapsulated in β-cyclodextrin-nanosponges (CN-CPT) increased solubility, was protected from degradation and inhibited the growth of prostate tumor cells both in vitro and in vivo. The aim of this study was to extend that work by assessing the CN-CPT effectiveness on ATC both in vitro and in vivo. Results showed that CN-CPT significantly inhibited viability, clonogenic capacity and cell-cycle progression of ATC cell lines showing a faster and enhanced effect compared to free CPT. Moreover, CN-CPT inhibited tumor cell adhesion to vascular endothelial cells, migration, secretion of pro-angiogenic factors (IL-8 and VEGF-α), expression of β-PIX, belonging to the Rho family activators, and phosphorylation of the Erk1/2 MAPK. Finally, CN-CPT significantly inhibited the growth, the metastatization and the vascularization of orthotopic ATC xenografts in SCID/beige mice without apparent toxic effects in vivo. This work extends the previous insight showing that β-cyclodextrin-nanosponges are a promising tool for the treatment of ATC.

Solid lipid nanoparticles delivering anti-inflammatory drugs to treat inflammatory bowel disease: Effects in an in vivo model

AIM

To improve anti-inflammatory activity while reducing drug doses, we developed a nanoformulation carrying dexamethasone and butyrate.

METHODS

Dexamethasone cholesteryl butyrate-solid lipid nanoparticles (DxCb-SLN) were obtained with the warm microemulsion method. The anti-inflammatory activity of this novel nanoformulation has been investigated in vitro (cell adhesion to human vascular endothelial cells and pro-inflammatory cytokine release by lipopolysaccharide-induced polymorphonuclear cells) and in vivo (disease activity index and cytokine plasma concentrations in a dextran sulfate sodium-induced mouse colitis) models. Each drug was also administered separately to compare its effects with those induced by their co-administration in SLN at the same concentrations.

RESULTS

DxCb-SLN at the lowest concentration tested (Dx 2.5 nmol/L and Cb 0.1 μmol/L) were able to exert a more than additive effect compared to the sum of the individual effects of each drug, inducing a significant in vitro inhibition of cell adhesion and a significant decrease of pro-inflammatory cytokine (IL-1β and TNF-α) in both in vitro and in vivo models. Notably, only the DxCb nanoformulation administration was able to achieve a significant cytokine decrease compared to the cytokine plasma concentration of the untreated mice with dextran sulfate sodium-induced colitis. Specifically, DxCb-SLN induced a IL-1β plasma concentration of 61.77% ± 3.19%, whereas Dx or Cb used separately induced a concentration of 90.0% ± 2.8% and 91.40% ± 7.5%, respectively; DxCb-SLN induced a TNF-α plasma concentration of 30.8% ± 8.9%, whereas Dx or Cb used separately induced ones of 99.5% ± 4.9% and 71.1% ± 10.9%, respectively.

CONCLUSION

Our results indicate that the co-administration of dexamethasone and butyrate by nanoparticles may be beneficial for inflammatory bowel disease treatment.

Cyclodextrin-Based Nanohydrogels Containing Polyamidoamine Units: A New Dexamethasone Delivery System for Inflammatory Diseases

Glucocorticoids are widely prescribed in treatment of rheumatoid arthritis, asthma, systemic lupus erythematosus, lymphoid neoplasia, skin and eye inflammations. However, well-documented adverse effects offset their therapeutic advantages. In this work, novel nano-hydrogels for the sustained delivery of dexamethasone were designed to increase both bioavailability and duration of the administered drug and reducing the therapeutic dose. Hydrogels are soft materials consisting of water-swollen cross-linked polymers to which the insertion of cyclodextrin (CD) moieties adds hydrophobic drug-complexing sites. Polyamidoamines (PAAs) are biocompatible and biodegradable polymers apt to create CD moieties in hydrogels. In this work, β or γ-CD/PAA nanogels have been developed. In vitro studies showed that a pretreatment for 24⁻48 h with dexamethasone-loaded, β-CD/PAA nanogel (nanodexa) inhibits adhesion of Jurkat cells to human umbilical vein endothelial cells (HUVEC) in conditions mimicking inflammation. This inhibitory effect was faster and higher than that displayed by free dexamethasone. Moreover, nanodexa inhibited COX-2 expression induced by PMA+A23187 in Jurkat cells after 24⁻48 h incubation in the 10^-8⁻10^-5 M concentration range, while dexamethasone was effective only at 10^-5 M after 48 h treatment. Hence, the novel nanogel-dexamethasone formulation combines faster action with lower doses, suggesting the potential for being more manageable than the free drug, reducing its adverse side effects.

DNA damage by lipid peroxidation products: implications in cancer, inflammation and autoimmunity

Oxidative stress and lipid peroxidation (LPO) induced by inflammation, excess metal storage and excess caloric intake cause generalized DNA damage, producing genotoxic and mutagenic effects. The consequent deregulation of cell homeostasis is implicated in the pathogenesis of a number of malignancies and degenerative diseases. Reactive aldehydes produced by LPO, such as malondialdehyde, acrolein, crotonaldehyde and 4-hydroxy-2-nonenal, react with DNA bases, generating promutagenic exocyclic DNA adducts, which likely contribute to the mutagenic and carcinogenic effects associated with oxidative stress-induced LPO. However, reactive aldehydes, when added to tumor cells, can exert an anticancerous effect. They act, analogously to other chemotherapeutic drugs, by forming DNA adducts and, in this way, they drive the tumor cells toward apoptosis. The aldehyde-DNA adducts, which can be observed during inflammation, play an important role by inducing epigenetic changes which, in turn, can modulate the inflammatory process. The pathogenic role of the adducts formed by the products of LPO with biological macromolecules in the breaking of immunological tolerance to self antigens and in the development of autoimmunity has been supported by a wealth of evidence. The instrumental role of the adducts of reactive LPO products with self protein antigens in the sensitization of autoreactive cells to the respective unmodified proteins and in the intermolecular spreading of the autoimmune responses to aldehyde-modified and native DNA is well documented. In contrast, further investigation is required in order to establish whether the formation of adducts of LPO products with DNA might incite substantial immune responsivity and might be instrumental for the spreading of the immunological responses from aldehyde-modified DNA to native DNA and similarly modified, unmodified and/or structurally analogous self protein antigens, thus leading to autoimmunity.

Role of Anti-Osteopontin Antibodies in Multiple Sclerosis and Experimental Autoimmune Encephalomyelitis

Osteopontin (OPN) is highly expressed in demyelinating lesions in multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE). OPN is cleaved by thrombin into N- (OPN-N) and C-terminal (OPN-C) fragments with different ligands and functions. In EAE, administering recombinant OPN induces relapses, whereas treatment with anti-OPN antibodies ameliorates the disease. Anti-OPN autoantibodies (autoAbs) are spontaneously produced during EAE but have never been detected in MS. The aim of the study was to evaluate anti-OPN autoAbs in the serum of MS patients, correlate them with disease course, and recapitulate the human findings in EAE. We performed ELISA in the serum of 122 patients collected cross-sectionally, and 50 patients with relapsing–remitting (RR) disease collected at diagnosis and followed longitudinally for 10 years. In the cross-sectional patients, the autoAb levels were higher in the RR patients than in the primary- and secondary-progressive MS and healthy control groups, and they were highest in the initial stages of the disease. In the longitudinal group, the levels at diagnosis directly correlated with the number of relapses during the following 10 years. Moreover, in patients with active disease, who underwent disease-modifying treatments, autoAbs were higher than in untreated patients and were associated with low MS severity score. The autoAb displayed neutralizing activity and mainly recognized OPN-C rather than OPN-N. To confirm the clinical effect of these autoAbs in vivo, EAE was induced using myelin oligodendrocyte glycoprotein MOG_35–55 in C57BL/6 mice pre-vaccinated with ovalbumin (OVA)-linked OPN or OVA alone. We then evaluated the titer of antibodies to OPN, the clinical scores and in vitro cytokine secretion by spleen lymphocytes. Vaccination significantly induced antibodies against OPN during EAE, decreased disease severity, and the protective effect was correlated with decreased T cell secretion of interleukin 17 and interferon-γ ex vivo. The best effect was obtained with OPN-C, which induced significantly faster and more complete remission than other OPN vaccines. In conclusion, these data suggest that production of anti-OPN autoAbs may favor remission in both MS and EAE. Novel strategies boosting their levels, such as vaccination or passive immunization, may be proposed as a future strategy in personalized MS therapy.

Osteopontin Bridging Innate and Adaptive Immunity in Autoimmune Diseases

Osteopontin (OPN) regulates the immune response at multiple levels. Physiologically, it regulates the host response to infections by driving T helper (Th) polarization and acting on both innate and adaptive immunity; pathologically, it contributes to the development of immune-mediated and inflammatory diseases. In some cases, the mechanisms of these effects have been described, but many aspects of the OPN function remain elusive. This is in part ascribable to the fact that OPN is a complex molecule with several posttranslational modifications and it may act as either an immobilized protein of the extracellular matrix or a soluble cytokine or an intracytoplasmic molecule by binding to a wide variety of molecules including crystals of calcium phosphate, several cell surface receptors, and intracytoplasmic molecules. This review describes the OPN structure, isoforms, and functions and its role in regulating the crosstalk between innate and adaptive immunity in autoimmune diseases.