Tumoral Acidic pH-Responsive cis-Diaminodichloroplatinum-Incorporated Cy5.5-PEG- g-A-HA Nanoparticles for Targeting Delivery of CDDP against Cervical Cancer

A comparative study on the effects of human serum albumin and α-melanocyte-stimulating hormone fusion proteins on the anti-neuroinflammatory in the central nervous system of adult mice

The immunomodulatory effects of α-melanocyte stimulating hormone (α-MSH) in the central nervous system (CNS) have been investigated for forty years. The clinical applications of α-MSH are limited due to its short half-life. Our previous study has indicated that the short half-life of α-MSH can be extended by fusion with carrier human serum albumin (HSA) and this fusion protein has also retained the anti-inflammatory effect on the CNS. This improvement is still far from the clinical requirements. Thus, we expected to enhance the half-life and activity of the fusion protein by optimizing the linker peptide to get closer to clinical requirements. In a previous study, we screened out two candidates in vitro experiments with a flexible linker peptide (fusion protein with flexible linker peptide, FPFL) and a rigid linker peptide (fusion protein with rigid linker peptide, FPRL), respectively. However, it was not sure whether the anti-inflammatory effects in vitro could be reproduced in vivo. Our results show that FPRL is the best candidate with a longer half-life compared to the traditional flexible linker peptides. Meanwhile, the ability of FPRL to penetrate the blood-brain barrier (BBB) was enhanced, and the inhibition of TNF-α and IL-6 was improved. We also found that the toxicity of FPRL was decreased. All of the results suggested that trying to choose the rigid linker peptide in some fusion proteins may be a potential choice for improving the unsatisfactory characteristics.

Therapeutic Copolymer from Salicylic Acid and l-Phenylalanine as a Nanosized Drug Carrier for Orthotopic Breast Cancer with Lung Metastasis

Nanoparticle (NP)-mediated drug delivery systems are promising for treating various diseases. However, clinical translation has been delayed by a variety of limitations, such as weak drug loading, nonspecific drug leakage, lack of bioactivity, and short blood circulation. These issues are in part due to the unsatisfactory function of biomaterials for nanocarriers. In addition, the synthesis procedures of drug carrier materials, especially polymers, were usually complicated and led to high cost. In this report, a bioactive copolymer of hydroxy acid and amino acid, poly(salicylic acid-co-phenylalanine) (PSP), was developed for the first time via a one-step rapid and facile synthesis strategy. The PSP could self-assemble into NPs (PSP-NPs) to co-load relatively hydrophilic sphingosine kinase 1 inhibitor (PF543 in HCl salt format) and highly hydrophobic paclitaxel (PTX) to form PF543/PTX@PSP-NPs with efficient dual drug loading. Encouragingly, PF543/PTX@PSP-NPs showed long blood circulation, good stability, and high tumor accumulation, leading to significantly enhanced therapeutic effects on breast cancer. Furthermore, PF543/PTX@PSP-NPs could additionally suppress the lung metastasis of breast cancer, and more importantly, the PSP-NPs themselves as therapeutic nanocarriers also showed an anti-breast cancer effect. With these combined advantages, this new polymer and corresponding NPs will provide valuable insights into the development of new functional polymers and nanomedicines for important diseases.

MTX-PEG-modified CG/DMMA polymeric micelles for targeted delivery of doxorubicin to induce synergistic autophagic death against triple-negative breast cancer

The chemotherapy of triple-negative breast cancer based on doxorubicin (DOX) regimens suffers from great challenges on toxicity and autophagy raised off-target. In this study, a conjugate methotrexate-polyethylene glycol (shorten as MTX-PEG)-modified CG/DMMA polymeric micelles were prepared to endue DOX tumor selectivity and synergistic autophagic flux interference to reduce systematic toxicity and to improve anti-tumor capacity. The micelles could effectively promote the accumulation of autophagosomes in tumor cells and interfere with the degradation process of autophagic flux, collectively inducing autophagic death of tumor cells. In vivo and in vitro experiments showed that the micelles could exert improved anti-tumor effect and specificity, as well as reduced accumulation and damage of chemotherapeutic drugs in normal organs. The potential mechanism of synergistic autophagic death exerted by the synthesized micelles in MDA-MB-231 cells has been performed by autophagic flux-related pathway.

Targeted Cancer Therapy via pH-Functionalized Nanoparticles: A Scoping Review of Methods and Outcomes

(1) Background: In recent years, several studies have described various and heterogenous methods to sensitize nanoparticles (NPs) to pH changes; therefore, in this current scoping review, we aimed to map current protocols for pH functionalization of NPs and analyze the outcomes of drug-loaded pH-functionalized NPs (pH-NPs) when delivered in vivo in tumoral tissue. (2) Methods: A systematic search of the PubMed database was performed for all published studies relating to in vivo models of anti-tumor drug delivery via pH-responsive NPs. Data on the type of NPs, the pH sensitization method, the in vivo model, the tumor cell line, the type and name of drug for targeted therapy, the type of in vivo imaging, and the method of delivery and outcomes were extracted in a separate database. (3) Results: One hundred and twenty eligible manuscripts were included. Interestingly, 45.8% of studies (n = 55) used polymers to construct nanoparticles, while others used other types, i.e., mesoporous silica (n = 15), metal (n = 8), lipids (n = 12), etc. The mean acidic pH value used in the current literature is 5.7. When exposed to in vitro acidic environment, without exception, pH-NPs released drugs inversely proportional to the pH value. pH-NPs showed an increase in tumor regression compared to controls, suggesting better targeted drug release. (4) Conclusions: pH-NPs were shown to improve drug delivery and enhance antitumoral effects in various experimental malignant cell lines.

A Procedurally Activatable Nanoplatform for Chemo/Chemodynamic Synergistic Therapy

The responsive nano-drug delivery systems based on the complex characteristics of the tumor microenvironment (TME), such as acidic pH, hypoxia, and hydrogen peroxide (H2O2) overexpression, could enhance the biological activity...

Dasatinib self-assembled nanoparticles decorated with hyaluronic acid for targeted treatment of tumors to overcome multidrug resistance

Multidrug resistance (MDR) and lack of targeting specificity are the main reasons why traditional drug therapies fail and produce toxic side effects in cancer chemotherapy. In order to increase targeting specificity and maximize therapeutic efficacy, new intelligent drug delivery systems are needed. In this study, we prepared the hyaluronic acid (HA) conjugated dasatinib (DAS) and D-α-tocopherol acid polyethylene glycolsuccinate (TPGS) copolymer nanoparticles (THD-NPs). The water solubility of the hydrophobic drug DAS was improved by chemically linking with HA. HA can bind to the over-expressed CD44 protein of tumor cells to increase targeting specificity, TPGS can inhibit the activity of P-glycoprotein (P-gp), and increase the intracellular accumulation of drugs. The prepared drug-loaded nanoparticle has a particle size of 82.23 ± 1.07 nm with good in vitro stability. Our in vitro studies showed that THD-NPs can be released more rapidly in a weakly acidic environment (pH = 5.5) than in a normal physiological environment (pH = 7.4), which can realize the selective release of nanoparticles in tumor cells. Compared to free drugs, THD-NPs showed more efficient cellular uptake, effectively increased the cytotoxic effect of DAS on nasopharyngeal carcinoma HNE1 cells drug resistance HNE1/DDP cells and increased the accumulation of drugs in HNE1/DDP cells, which may be due to the inhibitory effect of TPGS on the efflux function of P-gp. In vivo experiments showed that THD-NPs can effectively inhibit tumor growth without obvious side effects. In conclusion, the targeted and pH-sensitive nanosystem, we designed has great potential to overcome drug resistance and increase therapeutic effects in cancer treatment.

Self-Assembled Nanosized Vehicles from Amino Acid-Based Amphiphilic Polymers with Pendent Carboxyl Groups for Efficient Drug Delivery

Developing safe and efficient delivery vehicles for chemotherapeutic drugs has been a long-standing demanding. Amino acid-based polymers are promising candidates to address this challenge due to their excellent biocompatibility and biodegradation. Herein, a series of well-defined amphiphilic block copolymers were prepared by PET-RAFT polymerization of N-acryloyl amino acid monomers. By altering monomer types and the block ratio of the copolymers, the copolymers self-assembled into nanostructures with various morphologies, including spheres, rod-like, fibers, and lamellae via hydrophobic and hydrogen bonding interactions. Significantly, the nanoparticles (NPs) assembled from amphiphilic block copolymers poly(N-acryloyl-valine)-b-poly(N-acryloyl-aspartic acid) (PV-b-PD) displayed an appealing cargo loading efficiency (21.8-32.6%) for a broad range of drugs (paclitaxel, doxorubicin (DOX), cisplatin, etc.) due to strong interactions. The DOX-loaded PV-b-PD NPs exhibited rapid cellular uptake (within 1 min) and a great therapeutic performance. These drug delivery systems provide new insights for regulating the controlled morphologies and improving the efficiency of drug delivery.

Extended-release of therapeutic microRNA via a host-guest supramolecular hydrogel to locally alleviate renal interstitial fibrosis

Activated fibroblasts are critical contributors to renal interstitial fibrosis thus becoming the cellular target for fibrosis treatment. Previously, microRNA 29 b (miR-29 b) is shown to be down-regulated in various animal models of renal fibrosis. Herein, we describe a facile strategy to achieve localized and sustained delivery of therapeutic microRNA to the kidney via a host-guest supramolecular hydrogel. Specifically, cationic bovine serum albumin is used to complex with miR-29 b to afford nanocomplexes (cBSA/miR-29 b), which is proven to specifically inhibit fibroblast activation in a dose-dependent manner in vitro. Following unilateral ureteral obstruction in mice, a single injection of the hydrogel loaded with cBSA/miR-29 b in vivo, significantly down-regulated proteins and genes related to fibrosis for up to 21 days without affecting the normal liver or kidney functions. Overall, the localized delivery of cBSA/miR-29 b via a host-guest supramolecular hydrogel represents a safe and effective intervention strategy to delay and reverse the progression of interstitial renal fibrosis.

Near-infrared light-triggered nanobomb for in situ on-demand maximization of photothermal/photodynamic efficacy for cancer therapy

Currently, the in situ on/off switch of PTT/PDT reagents for tumor treatment has evoked considerable interest in the field of cancer therapy. However, the actual PTT/PDT therapy efficacy in tumor treatment is largely restricted by the PTT/PDT reagents' aggregation issues during their release from the hydrophobic carrier to the hydrophilic tumor microenvironment. Thus, it remains a challenge to break through the therapy barrier caused by the PTT/PDT agent aggregation and achieve substantial improvement of anticancer efficacy. In this work, we developed a novel near-infrared (NIR) light-responsive and gas bubble-generated liposomal nanobomb (Cy/Ce6/CO2-Lip-FA) through the co-encapsulation of PTT/PDT reagents with gas precursor into the hydrophobic and hydrophilic regions of liposomes, respectively, in order to overcome the aggregation issues and substantially improve the synergistic PTT/PDT efficacy. Upon arrival at the tumor region, the PS phototoxicity of Cy/Ce6/CO2-Lip-FA could be effectively switched on through CO2 generation induced by the PTT effect of Cypate upon NIR irradiation. The gas bubble burst can remarkably suppress the aggregation of Cypate/Ce6 and extremely enhance the synergistic PTT/PDT efficacy. These results indicate that the proposed NIR-responsive and gas bubble-functionalized liposomal nanobomb is a highly promising platform for tumor treatment with better therapeutic efficacy.

Fluorescent Nanoparticles for Targeted Tumor Imaging and DNA Tracking Gene Delivery In Vitro/In Vivo

Fluorescence detection is desirable to track the gene transfer process in order to explain the mechanism. Here, a fluorescent nanoparticle, diketopyrrolopyrrole-based liposome (DPL), was prepared for DNA delivery and tumor imaging in vitro and in vivo. The process to deliver DNA into cells was detected in real time by DPL according to the fluorescent property. The transfection efficacies (TEs) for luciferase and enhanced green fluorescent protein (EGFP) analysis of DPL were 1.5 times those of the commercial transfection agent Lipo 2000. Importantly, the DPL/DNA system has high EGFP TE in vivo with tumor targeting ability. This work provided an effective strategy for monitoring transfection processes.

Poly-γ-glutamic acid derived nanopolyplexes for up-regulation of gamma-glutamyl transpeptidase to augment tumor active targeting and enhance synergistic antitumor therapy by regulating intracellular redox homeostasis

The active targeting strategy has achieved inspiring progress for drug accumulation in tumor therapy; however, the insufficient expression level of many potential receptors poses challenges for drug delivery. Poly-γ-glutamic acid (γ-pGluA), a naturally occurring anionic biopolymer, showed high affinity with tumor-associated gamma-glutamyl transpeptidase (GGT), which localized on the cell surface and exhibited intracellular redox homeostasis-dependent expression pattern; thus, GGT was utilized for mediating endocytosis of nanoparticles. Herein, GGT-targeting nanopolyplexes (γ-pGluA-CSO@Fe³⁺, PCFN) consisting of cationic chitosan and GGT-targeting γ-pGluA blended with iron ion were constructed to load reactive oxygen species-induced menadione (MA) and doxorubicin, which were utilized to investigate the mechanism of GGT up-regulation. Briefly, the pretreated PCFN/MA induced an intracellular oxidative stress environment, which facilitated adjusted up-regulated GGT expression and boosted tumor targeting. Subsequently, the destroyed redox homeostasis sensitized tumors for synergistic therapy. The innovative strategy of augmenting active targeting by disturbing intracellular redox homeostasis offers insight for the application of γ-pGluA-derived nanopolyplexes.

Supramolecular nanomaterials based on hollow mesoporous drug carriers and macrocycle-capped CuS nanogates for synergistic chemo-photothermal therapy

Multifunctional supramolecular nanoplatforms that integrate the advantages of different therapeutic techniques can trigger multimodal synergistic treatment of tumors, thus representing an emerging powerful tool for cancer therapeutics. Methods: In this work, we design and fabricate a multifunctional supramolecular drug delivery platform, namely Fa-mPEG@CP5-CuS@HMSN-Py nanoparticles (FaPCH NPs), consisting of a pyridinium (Py)-modified hollow mesoporous silica nanoparticles-based drug reservoir (HMSN-Py) with high loading capacity, a layer of NIR-operable carboxylatopillar[5]arene (CP5)-functionalized CuS nanoparticles (CP5-CuS) on the surface of HMSN-Py connected through supramolecular host-guest interactions between CP5 rings and Py stalks, and another layer of folic acid (Fa)-conjugated polyethylene glycol (Fa-PEG) antennas by electrostatic interactions capable of active targeting at tumor lesions, in a controlled, highly integrated fashion for synergistic chemo-photothermal therapy. Results: Fa-mPEG antennas endowed the enhanced active targeting effect toward cancer cells, and CP5-CuS served as not only a quadruple-stimuli responsive nanogate for controllable drug release but also a special agent for NIR-guided photothermal therapy. Meanwhile, anticancer drug doxorubicin (DOX) could be released from the HMSN-Py reservoirs under tumor microenvironments for chemotherapy, thus realizing multimodal synergistic therapeutics. Such a supramolecular drug delivery platform showed effective synergistic chemo-photothermal therapy both in vitro and in vivo. Conclusion: This novel supramolecular nanoplatform possesses great potential in controlled drug delivery and tumor cellular internalization for synergistic chemo-photothermal therapy, providing a promising approach for multimodal synergistic cancer treatment.

Injectable Hydrogels for Localized Cancer Therapy

Traditional intravenous chemotherapy is relative to many systemic side effects, including myelosuppression, liver or kidney dysfunction, and neurotoxicity. As an alternative method, the injectable hydrogel can efficiently avoid these problems by releasing drugs topically at the tumor site. With advantages of localized drug toxicity in the tumor site, proper injectable hydrogel as the drug delivery system has become a research hotspot. Based on different types and stages of cancer, a variety of hydrogel drug delivery systems were developed, including thermosensitive, pH-sensitive, photosensitive, and dual-sensitive hydrogel. In this review, the latest developments of these hydrogels and related drug delivery systems were summarized. In summary, our increasing knowledge of injectable hydrogel for localized cancer therapy ensures us that it is a more durable and effective approach than traditional chemotherapy. Smart release system reacting to different stimuli at different time according to the micro-environment changes in the tumor site is a promising tendency for further studies.

Tumor Targeting Strategies of Smart Fluorescent Nanoparticles and Their Applications in Cancer Diagnosis and Treatment

Advantages such as strong signal strength, resistance to photobleaching, tunable fluorescence emissions, high sensitivity, and biocompatibility are the driving forces for the application of fluorescent nanoparticles (FNPs) in cancer diagnosis and therapy. In addition, the large surface area and easy modification of FNPs provide a platform for the design of multifunctional nanoparticles (MFNPs) for tumor targeting, diagnosis, and treatment. In order to obtain better targeting and therapeutic effects, it is necessary to understand the properties and targeting mechanisms of FNPs, which are the foundation and play a key role in the targeting design of nanoparticles (NPs). Widely accepted and applied targeting mechanisms such as enhanced permeability and retention (EPR) effect, active targeting, and tumor microenvironment (TME) targeting are summarized here. Additionally, a freshly discovered targeting mechanism is introduced, termed cell membrane permeability targeting (CMPT), which improves the tumor-targeting rate from less than 5% of the EPR effect to more than 50%. A new design strategy is also summarized, which is promising for future clinical targeting NPs/nanomedicines design. The targeting mechanism and design strategy will inspire new insights and thoughts on targeting design and will speed up precision medicine and contribute to cancer therapy and early diagnosis.

Doxorubicin-loaded functionalized selenium nanoparticles for enhanced antitumor efficacy in cervical carcinoma therapy

Development of novel tumor-targeted drug vehicles for cancer therapy is very important and has become one of major topics for designing nanoscale chemotherapeutics delivery systems. In the present study, selenium nanoparticles (SeNPs) was decorated with hyaluronic acid (HA) to prepare HA-SeNPs nanoparticles which were used to load doxorubicin (DOX) to fabricate tumor-targeted functionalized selenium nanoparticles HA-Se@DOX. In vitro and in vivo antitumor activities of HA-Se@DOX in human cervical carcinoma treatment were investigated. HA-Se@DOX showed selective cellular uptakes between cervical cancer HeLa cells and human umbilical vein endothelial cells (HUVEC). In vitro release result indicated that DOX was released from HA-SeNPs faster in acidic environment in comparison with normal physiological environment and 76.9% DOX was released in pH 5.4 during initial 30 h. HA-Se@DOX showed high activity to inhibit HeLa cell proliferation and triggered HeLa cell apoptosis via activating Bcl-2 signaling pathway. In vivo antitumor study showed that HA-Se@DOX inhibited tumor growth through suppressing cancer cells proliferation and inducing cancer cells apoptosis. Interestingly, HA-Se@DOX exhibited stronger anticancer activity than free DOX and Se@DOX in vitro and in vivo. Additionally, HA-Se@DOX did not cause damage to major organs at the used dose. HA-Se@DOX is a promising antitumor agent for human cervical carcinoma treatment and this research provides a novel therapeutic strategy for cancer therapy.

Hyaluronic Acid-Decorated Laponite® Nanocomposites for Targeted Anticancer Drug Delivery

In this study, hyaluronic acid (HA), a natural polysaccharide that can specifically bind to CD44 receptors, was conjugated onto laponite® (LAP) nanodisks for the encapsulation and specific delivery of the anti-cancer drug doxorubicin (DOX) to CD44-overexpressed cancer cells. The prepared LM-HA could encapsulate DOX efficiently and release drug in a continuous manner with pH-responsiveness. In vitro cell viability assay proved that LM-HA had good biocompatibility, and drug-loaded LM-HA/DOX exhibited targeted anti-tumor effects against HeLa cells with CD44 receptors overexpressed. In addition, the flow cytometric detection and confocal laser scanning microscope results confirmed that LM-HA/DOX could be specifically internalized by HeLa cells via CD44-mediated endocytosis. Therefore, the HA-modified LAP nanodisks with high drug loading efficiency, pH-sensitive drug release properties and CD44 targetability might be an efficient nanoplatform for cancer chemotherapy.

Synthesis, characterization, and formulation of poly-puerarin as a biodegradable and biosafe drug delivery platform for anti-cancer therapy

Poly-puerarin, a novel biodegradable biomaterial as a drug delivery platform in anti-tumour therapy.