Superstable and Large-Scalable Organosilica-Micellar Hybrid Nanosystem via a Confined Gelation Strategy for Ultrahigh-Dosage Chemotherapy

Reduction-responsive supramolecular hybridized paclitaxel nanoparticles for tumor treatment

Powerful chemotherapeutics have been used to combat tumor cells, but serious adverse effects and poor therapeutic efficiency restrict their clinical performance. Herein, we developed reduction-responsive supramolecular hybridized paclitaxel nanoparticles (PTX@HOMNs) for improved tumor treatment. The nanocarrier is composed of F127 and strengthened by a disulfide bond linked organosilica network, which ensures the desirable stability during blood circulation and controlled drug release at tumor sites. The as-prepared PTX@HOMNs could effectively accumulate at tumor regions. After entering tumor cells, PTX@HOMNs can respond to intracellular glutathione, and trigger active drug release for chemotherapy. As a result, PTX@HOMNs exhibited potent antitumor activity against ovarian tumors in vitro and in vivo. Our work provides a deep insight into constructing simple and controlled drug delivery nanoplatforms for improved tumor treatment.

Hyaluronic acid-functionalized redox-responsive organosilica nanoparticles for targeted resveratrol delivery to attenuate acrylamide-induced toxicity

The purpose of this study is to construct a redox-responsive and targeted nanoparticle to effectively deliver resveratrol (Res) for alleviating acrylamide (ACR) toxicity. Here, Res-loaded tetrasulfide-containing organosilica nanoparticles (DSMSNs) functionalized with hyaluronic acid on the surface (DSMSNs@Res@HA) were prepared. The DSMSNs@Res@HA nanoparticles were spherical with an encapsulation efficiency of 46.68 ± 1.64 % and a hydrated particle size of about 237.73 nm. As expected, DSMSNs@Res@HA were capable of significantly protecting PC12 cells against ACR-induced damage in oxidative stress, mitochondrial membrane potential decrease, and cell apoptosis compared with free Res and DSMSNs@Res at the equivalent dose. Moreover, DSMSNs@Res@HA could be biodegraded and released Res in response to GSH stimulus. In vivo experiments suggested that DSMSNs@Res@HA significantly reduced histological damage in the brain, liver, and kidney of rats compared with free Res and DSMSNs@Res. After oral administration of DSMSNs@Res@HA, the intestinal flora of ACR-treated rats could be effectively regulated by improving the species uniformity and abundance as well as recovering the species diversity. According to these findings, DSMSNs@Res@HA is worth further investigation as a potential therapeutic nanomedicine to alleviate ACR toxicity and restore gut microbiota diversity.

Dual "Unlocking" Strategy to Overcome Inefficient Nanomedicine Delivery and Tumor Hypoxia for Enhanced Photodynamic-Immunotherapy

Lacking blood vessels is one of the main characteristics of most solid tumors due to their rapid and unrestricted growth, which thus causes the inefficient delivery efficiency of nanomedicine and tumor hypoxia. Herein, a dual "unlocking" strategy to overcome these obstacles is proposed by combining engineered hybrid nanoparticles (named ZnPc@FOM-Pt) with dexamethasone (DXM). It is verified that pretreatment of tumors with DXM can increase intratumorally micro-vessel density (delivery "unlocking") to enhance the tumor delivery efficiency of ZnPc@FOM-Pt and decrease HIF-1α expression. Correspondingly, more Pt can catalyze tumor-overexpressed H₂ O₂ to produce oxygen to further cause hypoxia "unlocking," ultimately achieving boosted ZnPc-based photodynamic therapy in vivo (tumor inhibition rate: 99.1%). Moreover, the immunosuppressive tumor microenvironment is efficiently reversed and the therapeutic effect of anti-PD-L1-based immunotherapy is promoted by this newly designed nanomedicine. This dual "unlocking" strategy provides an innovative paradigm on simultaneously enhancing nanomedicine delivery efficacy and hypoxia relief for tumor therapy.

In Situ Constructed Nano-Drug Depots through Intracellular Hydrolytic Condensation for Chemotherapy of Bladder Cancer

Intravesical administration of first-line drugs has shown failure in the treatment of bladder cancer owing to the poor tumor retention time of chemotherapeutics. Herein, we report an intracellular hydrolytic condensation (IHC) system to construct long-term retentive nano-drug depots in situ, wherein sustained drug release results in highly efficient suppression of bladder cancer. Briefly, the designed doxorubicin (Dox)-silane conjugates self-assemble into silane-based prodrug nanoparticles, which condense into silicon particle-based nano-drug depots inside tumor cells. Significantly, we demonstrate that the IHC system possesses highly potent antitumor efficacy, which leads to the regression and eradication of large established tumors and simultaneously extends the overall survival of air pouch bladder cancer mice compared with that of mice treated with Dox. The concept of intracellular hydrolytic condensation can be extended via conjugating other chemotherapeutic drugs, which may facilitate rational design of novel nanomedicines for augmentation of chemotherapy.

Iron oxide nanoparticles as a drug carrier reduce host immunosuppression for enhanced chemotherapy

Chemotherapy is still regarded as the main modality for cancer treatment. However, it often suppresses the host immune system, resulting in limited therapeutic effects. It is desirable to design a novel chemotherapeutic agent to reduce the level of immunosuppression. Herein, we designed bovine serum albumin (BSA)-bioinspired iron oxide nanoparticles (IONPs) as a nanocarrier to load anticancer drug mitoxantrone (MTX) for enhanced chemotherapy of orthotopic breast cancer. The treatment with IONPs@BSA-MTX complexes increased CD3⁺CD4⁺ and CD3⁺CD8⁺ T lymphocytes more than free MTX. The complexes effectively restored the host immune system and exhibited a better anticancer efficacy than free MTX. It was worth noting that the BSA-inspired IONPs were a satisfactory contrast agent for magnetic resonance imaging of tumors and lymph nodes. Our work provides a novel strategy for enhanced chemotherapy with low levels of immunosuppression in the treatment of breast cancer and other cancers.