Randomized phase I trial of antigen-specific tolerizing immunotherapy with peptide/calcitriol liposomes in ACPA+ rheumatoid arthritis

BACKGROUND. Antigen-specific regulation of autoimmune disease is a major goal. In seropositive rheumatoid arthritis (RA), T cell help to autoreactive B cells matures the citrullinated (Cit) antigen-specific immune response, generating RA-specific V domain glycosylated anti-Cit protein antibodies (ACPA VDG) before arthritis onset. Low or escalating antigen administration under “sub-immunogenic” conditions favors tolerance. We explored safety, pharmacokinetics, and immunological and clinical effects of s.c. DEN-181, comprising liposomes encapsulating self-peptide collagen II259-273 (CII) and NF-κB inhibitor 1,25-dihydroxycholecalciferol. METHODS. A double-blind, placebo-controlled, exploratory, single-ascending-dose, phase I trial assessed the impact of low, medium, and high DEN-181 doses on peripheral blood CII-specific and bystander Cit64vimentin59-71–specific (Cit-Vim–specific) autoreactive T cell responses, cytokines, and ACPA in 17 HLA-DRB1*04:01+ or *01:01+ ACPA+ RA patients on methotrexate. RESULTS. DEN-181 was well tolerated. Relative to placebo and normalized to baseline values, Cit-Vim–specific T cells decreased in patients administered medium and high doses of DEN-181. Relative to placebo, percentage of CII-specific programmed cell death 1+ T cells increased within 28 days of DEN-181. Exploratory analysis in DEN-181–treated patients suggested improved RA disease activity was associated with expansion of CII-specific and Cit-Vim–specific T cells; reduction in ACPA VDG, memory B cells, and inflammatory myeloid populations; and enrichment in CCR7+ and naive T cells. Single-cell sequencing identified T cell transcripts associated with tolerogenic TCR signaling and exhaustion after low or medium doses of DEN-181. CONCLUSION. The safety and immunomodulatory activity of low/medium DEN-181 doses provide rationale to further assess antigen-specific immunomodulatory therapy in ACPA+ RA

Translational nano-medicines: targeted therapeutic delivery for cancer and inflammatory diseases

With the advent of novel and personalized therapeutic approaches for cancer and inflammatory diseases, there is a growing demand for designing delivery systems that circumvent some of the limitation with the current therapeutic strategies. Nanoparticle-based delivery of drugs has provided means of overcoming some of these limitations by ensuring the drug payload is directed to the disease site and insuring reduced off-target activity. This review highlights the challenges posed by the solid tumor microenvironment and the systemic limitations for effective chemotherapy. It then assesses the basis of nanoparticle-based targeting to the tumor tissues, which helps to overcome some of the microenvironmental and systemic limitations to therapy. We have extensively focused on some of the tumor multidrug resistance mechanisms (e.g., hypoxia and aerobic glycolysis) that contribute to the development of multidrug resistance and how targeted nano-approaches can be adopted to overcome drug resistance. Finally, we assess the combinatorial approach and how this platform has been used to develop multifunctional delivery systems for cancer therapy. The review article also focuses on inflammatory diseases, the biological therapies available for its treatment, and the concept of macrophage repolarization for the treatment of inflammatory diseases

Macrophage-targeted delivery systems for nucleic acid therapy of inflammatory diseases

Inflammation is an immune response that marks several pathophysiological conditions in our body. Though adaptive immune cells play a major role in the progression of the disease, components of innate immune system, mainly monocytes and macrophages play the central role in onset of inflammation. Tissue-associated macrophages are widely distributed in the body showing tremendous anatomical and functional diversity and are actively involved in maintaining the homeostasis. They exhibit different phenotypes depending on their residing tissue microenvironment and the two major functional phenotypes are classically activated M1 phenotype showing pro-inflammatory characteristics and alternatively activated M2 phenotype demonstrating anti-inflammatory nature. Several cytokines, chemokines and other regulatory mediators delicately govern the balance of the two phenotypes in a tissue. This balance, however, is subverted during infection, injury or autoimmune response leading to increased population of M1 phenotype and subsequent chronic inflammatory disease states. This review underlines the role of macrophages in inflammatory diseases with an insight into potential molecular targets for nucleic acid therapy. Finally, some recent nanotechnology-based approaches to devise macrophage-specific targeted therapy have been highlighted

Targeting of nanoparticles in cancer: drug delivery and diagnostics

Anticancer agents continue to be a preferred therapeutic option for several malignancies. Despite their effectiveness, oncologists are continually looking for tumor-specific anticancer agents to prevent adverse effects in patients. Targeting of imaging agents to cancerous tissue is another area that is enthusiastically explored to circumvent some of the drawbacks that current imaging agents possess, including the inability to target small tumor cells, inadequate imaging period, and the risk of renal damage. Formulation scientists have explored nanotechnology-based delivery systems for targeting anticancer agents and tumor-imaging agents to cancer tissue. Targeting with nanotechnology-based delivery systems has been investigated by both passive and active mechanisms with significant clinical success. This review presents a discussion on targeting strategies used for the delivery of nanoparticles by passive and active mechanisms, focusing more specifically on active targeting of nanoparticles using albumin, folic acid, transferrin, and aptamers as targeting ligands

Tumor aerobic glycolysis: new insights into therapeutic strategies with targeted delivery

Introduction: Cancer cells acclimatize to the harsh tumor microenvironment by altering cellular metabolism in favor of aerobic glycolysis. This process provides a source of energy and also generates essential components for macromolecular biosynthesis, which enables cellular survival. As the dependence of cancer cells on glycolysis affects tumorigenesis, it has become an attractive target for therapeutic intervention. Several preclinical studies have shown the effectiveness of using biological targets from the glycolytic pathway for anticancer therapy.Areas covered: This review provides an insight into the glycolytic pathway, highlighting potential targets for glycolytic inhibition. We then discuss recent advancement in delivery strategies that have the potential to circumvent some of the problems posed by current glycolytic inhibitors, enabling resurrection of abandoned therapeutic agents.Expert opinion: Targeting the glycolysis pathway is a tactical approach for cancer therapy. However, the current nonspecific therapeutic strategies have several drawbacks such as poor bioavailability, unfavorable pharmacokinetic profile and associated nonspecific toxicity, thereby limiting preclinical investigation. In recent years, nanoparticle systems have received recognition for the delivery of therapeutic agents directly to the tumor tissue. Thus, it is envisaged that this strategy can be expanded for the delivery of current glycolytic inhibitors specifically to tumor tissues providing improved anticancer activity

Cosilencing of PKM-2 and MDR-1 sensitizes multidrug-resistant ovarian cancer cells to paclitaxel in a murine model of ovarian cancer

Tumor multidrug resistance (MDR) is a serious clinical challenge that significantly limits the effectiveness of cytotoxic chemotherapy. As such, complementary therapeutic strategies are being explored to prevent relapse. The altered metabolic state of cancer cells, which perform aerobic glycolysis, represents an interesting target that can enable discrimination between healthy cells and cancer cells. We hypothesized that cosilencing of genes responsible for aerobic glycolysis and for MDR would have synergistic antitumor effect. In this study, siRNA duplexes against pyruvate kinase M2 and multidrug resistance gene-1 were encapsulated in hyaluronic acid-based self-assembling nanoparticles. The particles were characterized for morphology, size, charge, encapsulation efficiency, and transfection efficiency. In vivo studies included biodistribution assessment, gene knockdown confirmation, therapeutic efficacy, and safety analysis. The benefit of active targeting of cancer cells was confirmed by modifying the particles' surface with a peptide targeted to epidermal growth factor receptor, which is overexpressed on the membranes of the SKOV-3 cancer cells. To augment the studies involving transplantation of a paclitaxel-resistant cell line, an in vivo paclitaxel resistance model was developed by injecting repeated doses of paclitaxel following tumor inoculation. The nanoparticles accumulated significantly in the tumors, hindering tumor volume doubling time (P < 0.05) upon combination therapy in both the wild-type (2-fold) and resistant (8-fold) xenograft models. Although previous studies indicated that silencing of MDR-1 alone sensitized MDR ovarian cancer to paclitaxel only modestly, these data suggest that concurrent silencing of PKM-2 improves the efficacy of paclitaxel against MDR ovarian cancer

Development and evaluation of PIK75 nanosuspension, a phosphatidylinositol-3-kinase inhibitor

Purpose: PIK75 is a specific inhibitor of the p110 α isoform of phosphatidylinositol-3-kinase, an enzyme which is upregulated in several human cancers. However its poor water solubility and stability has limited its pre-clinical development. Method: In our current work we developed and evaluated PIK75 nanosuspension prepared using high pressure homogenization technique. The nanosuspension was characterized for various properties such as size, surface charge and saturation solubility. The saturation solubility processing techniques were critically evaluated to optimize sample processing conditions. In vitro studies were conducted to determine the stability of the formulation and in vivo studies were carried out to understand the pharmacokinetic and tissue distribution properties of the nanosuspension. Results: The nanosuspension exhibited an 11-fold improvement in saturation solubility with drug recovery greater than 90% for 6 h in the nanosuspension system and in human plasma. In vivo studies indicated that both PIK75 suspension and nanosuspension showed a similar plasma pharmacokinetic profile however tissue distribution studies indicated lower PIK75 levels in the kidney post nanosuspension administration. Conclusion: The results of this study showed that PIK75 could be formulated as a nanosuspension to improve saturation solubility, enhance stability in plasma and minimize exposure to drug metabolizing tissues

Inhibition of hexokinase-2 with targeted liposomal 3-bromopyruvate in an ovarian tumor spheroid model of aerobic glycolysis

Background: The objective of this study was to evaluate the expression levels of glycolytic markers, especially hexokinase-2 (HK2), using a three-dimensional multicellular spheroid model of human ovarian adenocarcinoma (SKOV-3) cells and to develop an epidermal growth factor receptor-targeted liposomal formulation for improving inhibition of HK2 and the cytotoxicity of 3-bromopyruvate (3-BPA). Methods: Multicellular SKOV-3 tumor spheroids were developed using the hanging drop method and expression levels of glycolytic markers were examined. Non-targeted and epidermal growth factor receptor-targeted liposomal formulations of 3-BPA were formulated and characterized. Permeability and cellular uptake of the liposomal formulations in three-dimensional SKOV-3 spheroids was evaluated using confocal microscopy. The cytotoxicity and HK2 inhibition potential of solution form of 3-BPA was compared to the corresponding liposomal formulation by using cell proliferation and HK2 enzymatic assays. Results: SKOV-3 spheroids were reproducibly developed using the 96-well hanging drop method, with an average size of 900 μm by day 5. HK2 enzyme activity levels under hypoxic conditions were found to be higher than under normoxic conditions (