Enhanced anticancer activity of DM1-loaded star-shaped folate-core PLA-TPGS nanoparticles

Emerging non-antibody‒drug conjugates (non-ADCs) therapeutics of toxins for cancer treatment

The non-selective cytotoxicity of toxins limits the clinical relevance of the toxins. In recent years, toxins have been widely used as warheads for antibody‒drug conjugates (ADCs) due to their efficient killing activity against various cancer cells. Although ADCs confer certain targeting properties to the toxins, low drug loading capacity, possible immunogenicity, and other drawbacks also limit the potential application of ADCs. Recently, non-ADC delivery strategies for toxins have been extensively investigated. To further understand the application of toxins in anti-tumor, this paper provided an overview of prodrugs, nanodrug delivery systems, and biomimetic drug delivery systems. In addition, toxins and their combination strategies with other therapies were discussed. Finally, the prospect and challenge of toxins in cancer treatment were also summarized.

Quercetin inhibits the metabolism of arachidonic acid by inhibiting the activity of CYP3A4, thereby inhibiting the progression of breast cancer

BACKGROUND

Recent years have witnessed impressive growth in applying natural medicine in tumor treatment. Saffron is reported to elicit an inhibitory property against BC. Herein, we sought to explore the specific components and mechanistic basis of saffron's anti-breast carcinoma (BC) function.

METHODS

Bioinformatics analysis was employed to analyze saffron components' anti-BC activity and screen the corresponding target genes involved in BC. Then, the roles of the main saffron ingredient quercetin in the activity of BC cells were examined using CCK-8, MTS, flow cytometry, colony formation, Transwell, and Gelatin zymogram assays. Additionally, the interactions among Quercetin, EET, and Stat3 were assessed by immunofluorescence and Western blot, and LC-MS/MS determined the levels of AA, EETs, and CYP3A. Finally, BC xenograft mouse models were established to verify the anti-BC function of Quercetin in vivo.

RESULTS

Quercetin, the main active component of saffron, inhibited BC progression. Quercetin suppressed BC cell growth, migration, and invasion and inhibited CYP3A4 expression and activity in BC. Mechanistically, Quercetin down-regulated CYP3A4 to block the nuclear translocation of Stat3 by decreasing the metabolization of AA to EETs, thereby alleviating BC. Moreover, exogenously added EETs counteracted the anti-tumor effect of Quercetin on BC. Quercetin also inhibited the tumor growth of tumor-bearing nude mice.

CONCLUSION

Quercetin could inhibit the activity of CYP3A to down-regulate AA metabolites EETs, consequently hampering p-Stat3 and nuclear translocation, thus impeding BC development.

Spectroscopic and computational studies of the solid state photophysical properties of a biscoumarin dye

The solid state photophysical properties of the 3,3'-paraphenyl bis[6,8-dimethoxy-2H-chromen-2-one] symmetrical biscoumarin material were investigated by optical spectroscopy techniques and by theoretical calculations. Vibrational analysis using IR absorption and Raman scattering techniques carried out together with DFT theoretical calculations have confirmed the structure of this biscoumarin. The geometry optimization using different functionals reveal a nonplanar equilibrium structure with a dihedral between the phenyl and the pyran rings of about 142°. The UV-Visible absorption measurements and the TDDFT simulation show that this biscoumarin is characterized by a bicomponent feature resulting from ππ* electronic transitions and Intramolecular Charge Transfer (ICT). Solid state photoluminescence showed a bright blue-green emission at 506 nm with a large stokes shift estimated at 146 nm, and the temperature dependence study of this emission reveals two thermal evolution regimes. Finally, these good optical properties, as well as the stability of the emission, make this biscoumarin dye of potential interest for optoelectronic applications.

A DM1-doped porous gold nanoshell system for NIR accelerated redox-responsive release and triple modal imaging guided photothermal synergistic chemotherapy

Background

Although many treatments for breast cancer are available, poor tumour targeting limits the effectiveness of most approaches. Consequently, it is difficult to achieve satisfactory results with monotherapies. The lack of accurate diagnostic and monitoring methods also limit the benefits of cancer treatment. The aim of this study was to design a nanocarrier comprising porous gold nanoshells (PGNSs) co-decorated with methoxy polyethylene glycol (mPEG) and trastuzumab (Herceptin®, HER), a therapeutic monoclonal antibody that binds specifically to human epidermal receptor-2 (HER2)-overexpressing breast cancer cells. Furthermore, a derivative of the microtubule-targeting drug maytansine (DM1) was incorporated in the PGNSs.

Methods

Prepared PGNSs were coated with mPEG, DM1 and HER via electrostatic interactions and Au–S bonds to yield DM1-mPEG/HER-PGNSs. SK-BR-3 (high HER2 expression) and MCF-7 (low HER2) breast cancer cells were treated with DM1-mPEG/HER-PGNSs, and cytotoxicity was evaluated in terms of cell viability and apoptosis. The selective uptake of the coated PGNSs by cancer cells and subsequent intracellular accumulation were studied in vitro and in vivo using inductively coupled plasma mass spectrometry and fluorescence imaging. The multimodal imaging feasibility and synergistic chemo-photothermal therapeutic efficacy of the DM1-mPEG/HER-PGNSs were investigated in breast cancer tumour-bearing mice. The molecular mechanisms associated with the anti-tumour therapeutic use of the nanoparticles were also elucidated.

Result

The prepared DM1-mPEG/HER-PGNSs had a size of 78.6 nm and displayed excellent colloidal stability, photothermal conversion ability and redox-sensitive drug release. These DM1-mPEG/HER-PGNSs were taken up selectively by cancer cells in vitro and accumulated at tumour sites in vivo. Moreover, the DM1-mPEG/HER-PGNSs enhanced the performance of multimodal computed tomography (CT), photoacoustic (PA) and photothermal (PT) imaging and enabled chemo-thermal combination therapy. The therapeutic mechanism involved the induction of tumour cell apoptosis via the activation of tubulin, caspase-3 and the heat shock protein 70 pathway. M2 macrophage suppression and anti-metastatic functions were also observed.

Conclusion

The prepared DM1-mPEG/HER-PGNSs enabled nanodart-like tumour targeting, visibility by CT, PA and PT imaging in vivo and powerful tumour inhibition mediated by chemo-thermal combination therapy in vivo. In summary, these unique gold nanocarriers appear to have good potential as theranostic nanoagents that can serve both as a probe for enhanced multimodal imaging and as a novel targeted anti-tumour drug delivery system to achieve precision nanomedicine for cancers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-00824-5.

Enhanced effect of folated pluronic F87-PLA/TPGS mixed micelles on targeted delivery of paclitaxel

Targeted drug delivery systems have great potential to overcome the side effect and improve the bioavailability of conventional anticancer drugs. In order to further improve the antitumor efficacy of paclitaxel (PTX) loaded in folated Pluronic F87/poly(lactic acid) (FA-F87-PLA) micelles, D-α-tocopheryl poly(ethylene glycol) 1000 succinate (TPGS or Vitamin E TPGS) were added into FA-F87-PLA to form FA-F87-PLA/TPGS mixed micelles. The LE of PTX-loaded mixed micelles (13.5%) was highest in the mass ratio 5 to 3 of FA-F87-PLA to TPGS. The in vitro cytotoxicity assays indicated that the IC50 values for free PTX injections, PTX-loaded FA-F87-PLA micelles and PTX-loaded FA-F87-PLA/TPGS mixed micelles after 72h of incubation were 1.52, 0.42 and 0.037mg/L, respectively. The quantitative cellular uptake of coumarin 6-loaded FA-F87-PLA/TPGS and FA-F87-PLA micelles showed that the cellular uptake efficiency of mixed micelles was higher for 2 and 4h incubation, respectively. In vivo pharmacokinetic studies found that the AUC of PTX-loaded FA-F87-PLA/TPGS mixed micelles is almost 1.4 times of that of PTX-loaded FA-F87-PLA micelles. The decreased particle size and inhibition of P-glycoprotein effect induced by the addition of TPGS could result in enhancing the cellular uptake and improving the antitumor efficiency of PTX-loaded FA-F87-PLA/TPGS mixed micelles.

Indocyanine Green Loaded Magnetic Carbon Nanoparticles for Near Infrared Fluorescence/Magnetic Resonance Dual-Modal Imaging and Photothermal Therapy of Tumor

Malignant tumor incidences have been rapidly rising recently and are becoming a serious threat to human health. Herein, a multifunctional cancer targeted theranostic nanoplatform is developed by in situ growth of iron oxide magnetic nanoparticles on carbon nanoparticles, and then loaded with fluorescent dye indocyanine green (ICG@MCNPs). The loading of ICG on the nanoplatform significantly improves its photostability, and hence facilitates long-term near-infrared fluorescence (NIRF) imaging and efficient photothermal therapy (PTT) of tumor. The in vivo NIRF imaging reveals that ICG@MCNPs can be targeted to the tumor site. Moreover, in vivo magnetic resonance imaging also confirmed the efficient accumulation of ICG@MCNPs in the tumor site. Inspiringly, the subsequent PTT of tumor-bearing mice is achieved, as evidenced by the complete ablation of the tumor and the recovery of the physiological indexes to normal levels. Benefitting from its low-cost, simple preparation, and excellent dual-modal imaging and therapy, the ICG@MCNPs-based theranostic nanoplatform holds great promise in tumor-targeted nanomedicine.

Current Advances of Tubulin Inhibitors in Nanoparticle Drug Delivery and Vascular Disruption/Angiogenesis

Extensive research over the last decade has resulted in a number of highly potent tubulin polymerization inhibitors acting either as microtubule stabilizing agents (MSAs) or microtubule destabilizing agents (MDAs). These inhibitors have potent cytotoxicity against a broad spectrum of human tumor cell lines. In addition to cytotoxicity, a number of these tubulin inhibitors have exhibited abilities to inhibit formation of new blood vessels as well as disrupt existing blood vessels. Tubulin inhibitors as a vascular disrupting agents (VDAs), mainly from the MDA family, induce rapid tumor vessel occlusion and massive tumor necrosis. Thus, tubulin inhibitors have become increasingly popular in the field of tumor vasculature. However, their pharmaceutical application is halted by a number of limitations including poor solubility and toxicity. Thus, recently, there has been considerable interests in the nanoparticle drug delivery of tubulin inhibitors to circumvent those limitations. This article reviews recent advances in nanoparticle based drug delivery for tubulin inhibitors as well as their tumor vasculature disruption properties.

TPGS-modified liposomes for the delivery of ginsenoside compound K against non-small cell lung cancer: formulation design and its evaluation in vitro and in vivo

Objective

This work aimed at preparing ginsenoside compound K (GCK)-loaded liposomes modified with TPGS (GCKT-liposomes) to enhance solubility and targeting capability of GCK, as well as inhibit the efflux of GCK from tumour cells.

Methods

GCKT-liposomes were prepared by the thin-film hydration method and characterized by particle size, polydispersity, zeta potential and drug encapsulation efficiency. A549 cells were used as antitumour cell model to access the cellular uptake of the GCK and perform its antitumour function. The enhancement of in vivo antitumour efficacy of GCKT-liposomes was evaluated by nude mice bearing tumour model.

Key findings

The results showed that GCKT-liposomes achieved a comparatively high drug loading efficiency and reasonable particle size at the ratio of 7 : 3 (phospholipid: TPGS). The in vitro release demonstrated that the dissolution of GCK was remarkably improved by entrapping it into liposomes. In addition, GCKT-liposomes exhibited a great hypersensitizing effect on A549 cells, and the cellular uptake was enhanced. Compared with free GCK, the IC50 of GCKT-liposomes was significantly reduced (16.3 ± 0.8 vs 24.9 ± 1.0 μg/ml). In vivo antitumour assay also indicated that GCKT-liposomes achieved higher antitumour efficacy (67.5 ± 0.5 vs 40.8 ± 0.7%).

Conclusion

The novel GCKT-liposomes significantly improved the antitumour efficacy of GCK.

Novel folated Pluronic/poly(lactic acid) nanoparticles for targeted delivery of paclitaxel

In vivo prolonged circulation time and enhanced tumor resistant ability of targeted PTX-loaded FA–Pluronic–PLA nanoparticles.