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Carbon monoxide (CO) has emerged as a potential antitumor agent by inducing the dysfunction of mitochondria and the apoptosis of cancer cells. However, it remains challenging to deliver appropriate amount of CO into tumor to ensure efficient tumor growth suppression with minimum side effects. Herein we developed a CO prodrug-loaded nanomedicine based on the self-assembly of camptothecin (CPT) polyprodrug amphiphiles. The polyprodrug nanoparticles readily dissociate upon exposure to endogenous H 2 O 2 in the tumor, resulting in rapid release of CPT and generation of high-energy intermediate dioxetanedione. The latter can transfer the energy to neighboring CO prodrugs to activate CO production by chemiexcitation, while CPT promotes the generation of H 2 O 2 in tumors, which in turn facilitates cascade CPT and CO release. As a result, the polyprodrug nanoparticles display remarkable tumor suppression in both subcutaneous and orthotopic breast tumor-bearing mice owing to the self-augmented CPT release and CO generation. In addition, no obvious systemic toxicity was observed in mice treated with the metal-free CO prodrug-loaded nanomedicine, suggesting the good biocompatibility of the polyprodrug nanoparticles. Our work provides new insights into the design and construction of polyprodrug nanomedicines for synergistic chemo/gas therapy. We reported a CO prodrug-loaded polyprodrug nanoparticle for self-augmented synergistic chemo/gas cancer therapy. The polyprodrug nanoparticle can release CPT in the presence of H 2 O 2 and the energy produced during this process can activate the CO prodrug to generate CO. The released CPT induces H 2 O 2 generation in tumor cells to initiate consistent CPT and CO release, thus realizing effective tumor suppression via orchestrated chemo/gas therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Peptides are attracting increasing attention as therapeutic agents, as the technologies for peptide development and manufacture continue to mature. Concurrently, with booming research in nanotechnology for biomedical applications, peptides have been studied as an important class of components in nanomedicine, and they have been used either alone or in combination with nanomaterials of every reported composition. Peptides possess many advantages, such as smallness, ease of synthesis and modification, and good biocompatibility. Their functions in cancer nanomedicine, discussed in this review, include serving as drug carriers, as targeting ligands, and as protease-responsive substrates for drug delivery. [Copyright &y& Elsevier]

The metal-based drugs represented by cisplatin, carboplatin, and oxaliplatin, prevail in cancer treatment, whereas new therapeutics are extremely slow to step into the clinic. Poor pharmacokinetics, multidrug resistance, and severe side effects greatly limit the development of metal-based anticancer drugs. The robustness and modular composition of supramolecular coordination complexes allow for the incorporation of novel diagnostic and therapeutic modalities, showing promising potentials for precise cancer theranostics. In this mini review, we highlight the recent advances in the development of supramolecular coordination complexes as diagnostic and therapeutic agents. The key focuses of these reports lie in searching sophisticated coordination ligands and nanoformulations that can potentially solve the issues faced by current metal-based drugs including imaging, resistance, toxicity, and pharmacological deficiencies. [ABSTRACT FROM AUTHOR]

Multimodal imaging-guided synergistic combination therapy has shown great potential for cancer treatment. However, the nanocarrier-based theranostic systems suffer from batch-to-batch variation, complexity of multicomponent, poor drug loading, and carrier-related toxicity issues. To address these issues, herein we developed a novel carrier-free theranostic system with nanoscale characteristics for near-infrared fluorescence (NIRF) and photoacoustic (PA) dual-modal imaging-guided synergistic chemo-photothermal therapy (PTT). Indocyanine green (ICG) and epirubicin (EPI) could co-self-assemble into small molecular nanoparticles (NPs) in aqueous solution without any molecular precursor or excipient via collaborative interactions (electrostatic, π–π stacking, and hydrophobic interactions). The exceptionally high dual-drug loading (∼ 92 wt%) ICG-EPI NPs showed good physiological stability, preferable photothermal response, excellent NIRF/PA imaging properties, pH-/photo-responsive drug release behavior, and promoted cellular endocytosis compared with free ICG or EPI. Importantly, the ICG-EPI NPs showed excellent tumor targeting ability with high spatial resolution and deep penetration via in vivo NIRF/PA dual-modal imaging. Moreover, in comparison with individual chemotherapy or PTT, the combinational chemo-PTT therapy of ICG-EPI NPs with NIR laser irradiation synergistically induced apoptosis and death of cancer cells in vitro , and showed synergistic chemo-PTT efficiency in vivo as evidenced by highly efficient tumor ablation. Furthermore, the ICG-EPI NPs exhibited inappreciable toxicity. This co-self-assembly of both FDA-approved agents provides a safe and “Molecular economical” strategy in the rational design of multifunctional nano-theranostic systems for real-time self-monitoring intracellular drug delivery and targeting multimodal imaging-guided synergistic combination therapy. [ABSTRACT FROM AUTHOR]

Abstract: We report a type of photosensitizer (PS)-loaded micelles integrating cyanine dye as potential theranostic micelles for precise anatomical tumor localization via dual photoacoustic (PA)/near-infrared fluorescent (NIRF) imaging modalities, and simultaneously superior cancer therapy via sequential synergistic photothermal therapy (PTT)/photodynamic therapy (PDT). The micelles exhibit enhanced photostability, cell internalization and tumor accumulation. The dual NIRF/PA imaging modalities of the micelles cause the high imaging contrast and spatial resolution of tumors, which provide precise anatomical localization of the tumor and its inner vasculature for guiding PTT/PDT treatments. Moreover, the micelles can generate severe photothermal damage on cancer cells and destabilization of the lysosomes upon PTT photoirradiation, which subsequently facilitate synergistic photodynamic injury via PS under PDT treatment. The sequential treatments of PTT/PDT trigger the enhanced cytoplasmic delivery of PS, which contributes to the synergistic anticancer efficacy of PS. Our strategy provides a dual-modal cancer imaging with high imaging contrast and spatial resolution, and subsequent therapeutic synergy of PTT/PDT for potential multimodal theranostic application. [Copyright &y& Elsevier]

Abstract: As a part of an ongoing assessment of its mechanism of action, we evaluated the in vivo pharmacokinetics, tissue distribution, toxicity and antitumor efficacy of VEGF121/rGel, a novel fusion protein. Pharmacokinetic studies showed that VEGF121/rGel cleared from the circulation in a biphasic manner with calculated half-lives of 0.3 and 6h for the alpha and beta phases, respectively. Pharmacokinetic evaluation of 64Cu–DOTA–VEGF121/rGel showed relatively high blood retention 30min after injection (26.6±1.73% ID/g), dropping to 11.8±2.83% and 0.82±0.11% ID/g at 60 and 240min post injection, respectively. Tissue uptake studies showed that kidneys, liver and tumor had the highest drug concentrations 48h after administration. The maximum tolerated dose (MTD), based on a QOD×5 i.v. administration schedule, was found to be 18mg/kg with an LD50 of 25mg/kg. Treatment of BALB/c mice with VEGF121/rGel at doses up to the MTD caused no alterations in hematologic parameters. However, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) parameters increased in a dose-related manner. The no-observable-adverse-effect-level (NOAEL) was determined to be 20% of the MTD (3.6mg/kg). VEGF121/rGel treatment of mice bearing orthotopically-placed MDA-MB-231 breast tumors caused increased vascular permeability of tumor tissue by 53% compared to saline-treated controls. Immunohistochemical analysis showed significant tumor hypoxia and necrosis as a consequence of vascular damage. In summary, VEGF121/rGel appears to be an effective therapeutic agent causing focused damage to tumor vasculature with minimal toxic effects to normal organs. This agent appears to be an excellent candidate for further clinical development. [Copyright &y& Elsevier]

Abstract: Noninvasive imaging techniques have been considered important strategies in the clinic to monitor tumor early response to therapy. In the present study, we applied RGD peptides conjugated to iron oxide nanoparticles (IONP-RGD) as contrast agents in magnetic resonance imaging (MRI) to noninvasively monitor the response of a vascular disrupting agent VEGF121/rGel in an orthotopic glioblastoma model. RGD peptides were firstly coupled to IONPs coated with a crosslinked PEGylated amphiphilic triblock copolymer. In vitro binding assays confirmed that cellular uptake of particles was mainly dependent on the interaction between RGD and integrin αvβ3 of human umbilical vein endothelial cells (HUVEC). The tumor targeting of IONP-RGD was observed in an orthotopic U87 glioblastoma model. Finally, noninvasive monitoring of the tumor response to VEGF121/rGel therapy at early stages of treatment was successfully accomplished using IONP-RGD as a contrast agent for MRI, a superior method over common anatomical approaches which are based on tumor size measurements. This preclinical study can accelerate anticancer drug development and promote clinical translation of nanoprobes. [Copyright &y& Elsevier]

Abstract: TRAIL has received considerable attention as a potential anti-cancer agent due to its specific ability to target tumors. However, recombinant TRAIL has several limitations, such as, its short biological half-life, its inherent instability, and its potential hepatotoxicity. In this study, we developed a sustained release nanoparticle formulation of TRAIL and investigated its therapeutic effects in tumor-bearing mice. TRAIL-loaded nanoparticles (NPs) were prepared by mixing PEGylated heparin (PEG-HE), poly-l-lysine (PLL), and TRAIL. NPs prepared by the ionic interaction between polymer and TRAIL showed uniform spherical structures of diameter 213.3 ± 9.7 nm and a surface charge of 5.33 ± 1.2 mV. An in vitro study of the bioactivity of TRAIL in NPs showed that TRAIL-loaded PEG-HE/PLL NPs (TRAIL-PEG-NPs) were slightly less cytotoxic than TRAIL in vitro. To investigate pharmacokinetic parameters, TRAIL and TRAIL-PEG-NPs were intravenously injected into SD rats. The PEG-NP-based formulation demonstrated a 28.3 fold greater half-life than TRAIL alone. To evaluate the anti-tumor effect, TRAIL, TRAIL-loaded HE/PLL NPs (TRAIL-NPs), and TRAIL-PEG-NPs were intravenously injected into HCT-116 tumor-bearing BALB/c athymic mice. The TRAIL-PEG-NP formulation efficiently suppressed tumor growth (>70%), and histological findings confirmed that NPs induced significant tumor cell apoptosis without inducing liver toxicity. The PEG-exposed NP fabrication method applied in this study could be widely applied to protein and peptide delivery systems. [Copyright &y& Elsevier]

Abstract: The purpose of this work was to develop an effective PEGylated TNF-related apoptosis-inducing ligand (PEG-TRAIL) delivery system for antitumor therapy based on local injection to tumor sites that has a sustained effect without protein aggregation or an initial release burst. The authors designed poly (lactic-co-glycolic) acid (PLGA) microspheres that deliver PEG-TRAIL locally and continuously at tumor sites with sustained biological activity and compared its performance with that of TRAIL microspheres. TRAIL or PEG-TRAIL was microencapsulated into PLGA microspheres using a double-emulsion solvent extraction method. Prepared TRAIL and PEG-TRAIL microspheres showed entirely spherical, smooth surfaces. However, PEG-TRAIL microspheres exhibited a 2.07-fold higher encapsulation efficiency than TRAIL microspheres, and exhibited a tri-phasic in vitro release profile with a lower initial burst (15.8%) than TRAIL microspheres (42.7%). Furthermore, released PEG-TRAIL showed a continued ability to induce apoptosis over 14days. In vivo pharmacokinetic studies also demonstrated that PEG-TRAIL microspheres had a sustained release profile (18days), and that the steady-state concentration of PEG-TRAIL in rat plasma was reached at day 3 and maintained until day 15; its steady-state concentration in rat plasma changed from 1444.3±338.4 to 2697.7±419.7pg/ml. However, TRAIL microspheres were released out within 2days after administration. Finally, in vivo antitumor tests revealed that tumor growths were significantly more inhibited by a single dose of PEG-TRAIL microspheres than TRAIL microspheres when delivered at 300μg of TRAIL/mouse. Tumors taken from mouse treated with PEG-TRAIL microspheres showed 78.3% tumor suppression at 24days, and this was 3.02-fold higher than that observed for TRAIL microspheres (25.9% tumor inhibition). Furthermore, these improved pharmaceutical characteristics of PEG-TRAIL microspheres resulted in superior therapeutic effects without detectable side effects. These findings strongly suggest that PEG-TRAIL microspheres offer a new therapeutic strategy for the treatment of cancers. [Copyright &y& Elsevier]

Abstract: Recently, a disulfide-based cyclic RGD peptide called iRGD, that is, c(CRGDKGPDC), has been reported to interact with both integrin and neuropilin-1 receptors for cellular and deep tissue penetration to improve the imaging sensitivity and therapeutic efficacy. In this study, two new near-infrared fluorescent iRGD conjugates, that is, Ac-Cys(IRDye®800CW)-iRGD (1), and its dual labeling analog DOTA-Cys(IRDye®800CW)-iRGD (2) were synthesized via the specific mercapto–maleimide reaction for tumor imaging. Both 1 and 2 showed significant tumor localization in optical imaging of MDA-MB-435 tumor-bearing mice. The potential of such iRGD compounds in tumor-targeted imaging and drug delivery deserves further exploration. [Copyright &y& Elsevier]

Abstract: Curcumin (CCM), a yellow natural polyphenol extracted from turmeric (Curcuma longa), has potent anti-cancer properties as has been demonstrated in various human cancer cells. However, the widespread clinical application of this efficient agent in cancer and other diseases has been limited by its poor aqueous solubility and bioavailability. In this study, we prepared novel CCM-loaded human serum albumin (HSA) nanoparticles (CCM-HSA-NPs) for intravenous administration using albumin bound technology. Field emission scanning electron microscopy (FE-SEM) and dynamic light scattering (DLS) investigation confirmed a narrow size distribution in the 130–150nm range. Furthermore, CCM-HSA-NPs showed much greater water solubility (300-fold) than free CCM, and on storage, the biological activity of CCM-HSA-NPs was preserved with negligible activity loss. In vivo distributions and vascular endothelial cells transport studies demonstrated the superiority of CCM-HSA-NPs over CCM. Amounts of CCM in tumors after treatment with CCM-HSA-NPs were about 14 times higher at 1h after injection than that achieved by CCM. Furthermore, vascular endothelial cell binding of CCM increased 5.5-fold, and transport of CCM across a vascular endothelial cell monolayer by Transwell testing was 7.7-fold greater for CCM-HSA-NPs than CCM. Finally, in vivo antitumor tests revealed that CCM-HSA-NPs (10 or 20mg/kg) had a greater therapeutic effect (50% or 66% tumor growth inhibition vs. PBS-treated controls) than CCM (18% inhibition vs. controls) in tumor xenograft HCT116 models without inducing toxicity. We attribute this potent antitumor activity of CCM-HSA-NPs to enhanced water solubility, increased accumulation in tumors, and an ability to traverse vascular endothelial cell. [ABSTRACT FROM AUTHOR]