Pea-like nanocabins enable autonomous cruise and step-by-step drug pushing for deep tumor inhibition

Bacteria-derived outer membrane vesicles engineered with over-expressed pre-miRNA as delivery nanocarriers for cancer therapy

Outer membrane vesicles (OMVs) of Escherichia coli as nanoscale spherical vesicles have been recently used in cancer therapy as drug carriers. However, most of them need complicated methods to load cargos. Herein, we proposed an inexpensive and potentially mass-produced method for the preparation of OMV engineered with over-expressed pre-miRNA. In this work, we found that OMV can be released and inherit over-expressed tRNA^{Lys-pre-miRNA} from mother E. coli that directly used for the tumor therapy. The eukaryotic cells infection experiments revealed that the over-expressed pre-miRNA inside OMV could be released and processed into mature miRNAs with the aid of the camouflage of "tRNA scaffold". Moreover, the group in vivo treated with targeted OMV^{tRNA-pre-miR-126} obviously inhibited the expression of target oncogenic CXCR4, and significantly restrain the proliferation of breast cancer tissues. Together, these findings indicated that the OMV-based platform is a versatile and powerful strategy for personalized tumor therapy directly and specificity.

Autophagy responsive intra-intercellular delivery nanoparticles for effective deep solid tumor penetration

Deep tumor cells (cells in the center of solid tumors) play a crucial role in drug tolerance, metastasis, recurrence and microenvironment immune suppression. However, their deep location endows them with an untouched abdomen and makes them refractory to current treatments. Herein, we exploited the characteristic of higher autophagy in deep tumor cells than in superficial tumor cells and designed autophagy-responsive multifunctional nanoparticles (PGN) to enhance drug accumulation in deep tumor cells. PGNs were prepared by densely coating poly (lactic-co-glycolic acid) (PLGA) with cationic autophagy-responsive cell-penetrating peptide (GR9) and anionic 2,3-dimethylmaleic anhydride (DMA)-modified DSPE-PEG. The suitable nanoparticle size (122.4 nm) and charge-neutral surface (0.21 mV) of the NPs enabled long blood circulation. The hydrolysis of surface-anchored anionic DMA in the acidic microenvironment led to the exposure of the GR9 peptide and enhance tumor penetration. Once the PGN arrived in deep tumor cells with strong autophagy, GR9 was cut off by an autophagy shear enzyme, and the nanoparticles remained in the cells to undergo degradation. Furthermore, we prepared docetaxel (DTX) and chloroquine (CQ) loaded d-PGN. CQ inhibits autophagosome fusion with lysosomes, resulting in autophagosome accumulation, which further enhances the sensitivity of d-PGN to autophagy and their deep tumor retention. In vivo experiments showed that drug-loaded d-PGN achieved excellent antitumor efficacy with a peak inhibition rate of 82.1%. In conclusion, autophagy-responsive multifunctional nanoparticles provide a novel potential strategy for solid tumor treatment.

Progress in cancer drug delivery based on AS1411 oriented nanomaterials

Targeted cancer therapy has become one of the most important medical methods because of the spreading and metastatic nature of cancer. Based on the introduction of AS1411 and its four-chain structure, this paper reviews the research progress in cancer detection and drug delivery systems by modifying AS1411 aptamers based on graphene, mesoporous silica, silver and gold. The application of AS1411 in cancer treatment and drug delivery and the use of AS1411 as a targeting agent for the detection of cancer markers such as nucleoli were summarized from three aspects of active targeting, passive targeting and targeted nucleic acid apharmers. Although AS1411 has been withdrawn from clinical trials, the research surrounding its structural optimization is still very popular. Further progress has been made in the modification of nanoparticles loaded with TCM extracts by AS1411.

Hyaluronic acid-coated metal-organic frameworks benefit the ROS-mediated apoptosis and amplified anticancer activity of artesunate

Artesunate (AS), as an effective new tumour treatment drug, induces cancer cell death based on high intracellular reactive oxygen species (ROS) produced by interacting with ferrous ions. However, the relatively low intracellular ferrous iron ion concentrations and the low efficiency of ROS generation limit its clinical application. Herein, we developed a metal-organic framework-Fe²⁺ (MOF), and AS was loaded in the MOF and then coated with hyaluronic acid (HA) on the surface of the MOF (HA@MOF-AS) for targeted and enhanced cancer treatment. HA@MOF-AS has high loading efficiency, good monodispersity, biocompatibility, strong cell uptake capacity and high intracellular ROS production, and it can target tumour tissues. In addition, in vivo anticancer studies have shown that HA@MOF-AS not only has high accumulation in tumours but also significantly inhibits tumour growth without significant damage to major organs. Therefore, HA@MOF-AS has excellent potential and may open a new approach for targeted cancer treatment.

Hyaluronic acid hydrophilic surface rehabilitating curcumin nanocrystals for targeted breast cancer treatment with prolonged biodistribution

Due to its high therapeutic efficiency and low systemic toxicity, natural bioactive curcumin has attracted more and more attention as a potential antineoplastic drug.