Traditional Chinese medicine-combination therapies utilizing nanotechnology-based targeted delivery systems: a new strategy for antitumor treatment

Enhanced antitumour efficacy of functionalized doxorubicin plus schisandrin B co-delivery liposomes via inhibiting epithelial-mesenchymal transition

Non-small cell lung cancer (NSCLC) is a malignant cancer characterized by easy invasion, metastasis and poor prognosis, so that conventional chemotherapy cannot inhibit its invasion and metastasis. Doxorubicin (DOX), as a broad-spectrum antitumour drug, cannot be widely used in clinic because of its poor targeting, short half-life, strong toxicity and side effects. Therefore, the aim of our study is to construct a kind of PFV modified DOX plus schisandrin B liposomes to solve the above problems, and to explore its potential mechanism of inhibiting NSCLC invasion and metastasis. The antitumour efficiency of the targeting liposomes was carried out by cytotoxicity, heating ablation, wound healing, transwell, vasculogenic mimicry channels formation and metastasis-related protein tests in vitro. Pharmacodynamics were evaluated by tumour inhibition rate, HE staining and TUNEL test in vivo. The enhanced anti-metastatic mechanism of the targeting liposomes was attributed to the downregulation of vimentin, vascular endothelial growth factor, matrix metalloproteinase 9 and upregulation of E-cadherin. In conclusion, the PFV modified DOX plus schisandrin B liposomes prepared in this study provided a treatment strategy with high efficiency for NSCLC.

Celastrol Self-Stabilized Nanoparticles for Effective Treatment of Melanoma

Background

Celastrol (CEL), a triterpene extracted from the Chinese herb tripterygium wilfordii, has been reported to have profound anticancer activities. However, poor water solubility and high side toxicities have severely restricted the clinical applications of CEL.

Purpose

We proposed a facile “in situ drug conjugation-induced self-assembly” strategy to prepare CEL-loaded nanoparticles (CEL-NPs) that exhibited enhanced antitumor activity against melanoma.

Methods

First, the CEL was chemically conjugated onto a methoxyl poly(ethylene glycol)-b-poly(L-lysine) (mPEG-PLL) backbone, resulting in the conversion of the double hydrophilic mPEG-PLL polymer into an amphiphilic polymer prodrug, mPEG-PLL/CEL. The obtained mPEG-PLL/CEL could self-assemble into stable micelles in aqueous solution due to the hydrophobic association of CEL moieties in the side chains and the possible electrostatic interaction between the carboxyl group in CEL and the residue amine group in the PLL segment. Thus, the obtained mPEG-PLL/CEL nanoparticles were named CEL self-stabilized nanoparticles (CEL-NPs), which were then characterized by dynamic light scattering and transmission electron microscopy. Furthermore, the antitumor effects of the CEL-NPs were investigated by an MTT assay in vitro and in a B16F10 tumor-bearing mice model.

Results

The CEL-NPs exhibited sustained drug release behavior and were effectively endocytosed by B16F10 cells. Furthermore, the in vivo antitumor evaluation demonstrated that the CEL-NPs had remarkably higher tumor growth inhibition rates and lower systemic side effects than free CEL.

Conclusion

In summary, our present work not only demonstrates the generation of stable CEL-loaded nanoparticles for the efficient treatment of melanoma but also describes a general way to prepare drug self-stabilized nanomedicine for anticancer therapy.

Encapsulation of crocetin into poly (lactic-co-glycolic acid) nanoparticles overcomes drug resistance in human ovarian cisplatin-resistant carcinoma cell line (A2780-RCIS)

Nanoparticles and herbal medicines have gained considerable attention in overcoming multidrug resistance through different mechanisms. In this study, the effects of poly (Lactic-co-glycolic acid)-crocetin nanoparticles (PLGA-Crt NPs) on MRP₁ and MRP₂ activity in a human ovarian cisplatin-resistant carcinoma cell line (A2780-RCIS) and its parental form (A2780) were evaluated. PLGA-Crt NPs were formulated and then characterized. The cytotoxic effect of Crt, PLGA-Crt NPs, and empty PLGA NPs was assessed using MTT test in A2780 and A2780-RCIS cells. The effect of PLGA-Crt NPs on MRP₁ and MRP₂ mRNA expression was evaluated by Real-Time qRT-PCR. The impact of PLGA-Crt NPs on the functioning of MRP transporters was assessed by the doxorubicin efflux assay. The particle size, entrapment efficiency (EE) and loading capacity (LC) of PLGA-Crt NPs were obtained about 239.8 ± 9 nm, 79 ± 3% and 4.9 ± 0.2%, respectively. The PLGA-Crt NPs IC₅₀ values were obtained 104 ± 3 µM and 96 ± 2 µM in A2780 and A2780-RCIS cell lines, respectively. The Real-time RT-PCR results demonstrated the inhibition of mRNA expression of MRP₂ in all studied concentrations (up to 67 ± 8% at 100 µM) in A2780-RCIS cells. PLGA-Crt NPs showed more indirect efflux inhibition (up to 70 ± 5%) compared to direct inhibition (up to 49 ± 5%). The encapsulation of crocetin into PLGA NPs can increase its inhibitory effects on drug resistance by downregulating MRP₂ transporters.