pH-responsive delivery of anti-metastatic niclosamide using mussel inspired polydopamine nanoparticles

Salvianolic acid B-loaded polydopamine-modified hollow mesoporous organic silica nanoparticles for treatment of breast cancer metastasis via suppressing cancer-associated fibroblasts

OBJECTIVE

Drug Delivery System was constructed using dopamine-coated organic-inorganic hybrid hollow mesoporous organic silica nanoparticles (HMON-PDA) as drug carriers and salvianolic acid B (SAB) as a model drug. Then, we further investigated whether it can inhibit lung metastasis of breast cancer by inhibiting cancer-associated fibroblasts (CAFs).

METHODS

The organic-inorganic hybrid hollow mesoporous organic silica nanoparticles (HMON) were prepared. The particle size, zeta potential, and polydispersion coefficient were characterized. High-performance liquid chromatography was used to determine the effect of different feed ratios of HMON and SAB on drug loading rate. Then, SAB-loaded HMON were modified by polydopamine, which is called SAB@HMON-PDA. Cell viability was detected by MTT assay. The migration of 4T1 cells was investigated by wound healing experiment, and the invasion of 4T1 cells was detected by the transwell method. Finally, the mouse breast cancer lung metastasis models were used to explore whether SAB@HMON-PDA can inhibit lung metastasis of breast cancer by inhibiting CAFs.

RESULTS

The obtained nanoparticles have hollow spherical structure. The average particle sizes of HMON, SAB@HMON, and SAB@HMON-PDA were 143.5 ± 0.03, 138.3 ± 0.02, and 172.3 ± 0.18 nm, respectively. The zeta potentials were -44.33±0.15, -41.4 ± 1.30, and -24.13±0.47 mV, respectively. When the ratio of HMON to SAB was 2:1, the drug loading rate reached (18.37±0.04)%. In addition, the prepared SAB@HMON-PDA responded to release SAB under acidic and GSH conditions. The prepared SAB@HMON-PDA could inhibit the migration and invasion of 4T1 cells. The results showed that SAB@HMON-PDA and SAB could inhibit lung metastasis of breast cancer in mice, and SAB@HMON-PDA had a more significant inhibitory effect than SAB.

CONCLUSION

We successfully prepared SAB@HMON-PDA with the dual response of pH and GSH. SAB@HMON-PDA can inhibit the migration and invasion of 4T1 cells, and the effect is more significant than free SAB. This inhibitory effect may be related to the inhibition of CAFs. In vivo experiments demonstrated that SAB@HMON-PDA can inhibit lung metastasis of breast cancer by inhibiting CAFs, and its effect was more significant than that of free SAB.

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.

NIR as a "trigger switch" for rapid phase change, on-demand release, and photothermal synergistic antibacterial treatment with chitosan-based temperature-sensitive hydrogel

Temperature-sensitive hydrogels have shown good performances as wound dressing owing to their ability to fill wounds in the liquid state and to release drugs in a solid state. However, their treatment efficiency is restricted by the phase transition time. In this study, we developed a photothermal synergistic chitosan-based temperature-sensitive hydrogel, h-EGF-CS/β-GP-MPDA@Cip, with the unique properties of rapid phase transition and drug release under near-infrared light (NIR). High antibacterial efficiency was achieved when we covered infected mice wounds with hydrogels. The local high temperature produced under NIR illumination not only accelerated the formation of a porous gel to release the loaded drug on-demand, but also dissolved bacteria, achieving synergistic anti-bacterial treatment. In addition, the healing cycle of wounds could be significantly shortened by adding human epidermal growth factor (h-EGF) in the hydrogel. Overall, the developed temperature-sensitive hydrogel could utilise NIR as a "trigger switch" for on-demand drug release and photothermal-enhanced antibacterial treatment during the rapid phase change process.

Mesoporous Silica Nanoparticle-Based Combination of Niclosamide and Doxorubicin: Effect of Treatment Regimens on Breast Cancer Subtypes

Overexpressed Wnt/β-catenin signaling acts as a major cancer driver and plays an important role in the development of resistance against cancer chemotherapy. Therefore, the combinatorial approach of downregulating Wnt/β-catenin signaling along with using a chemotherapeutic agent may improve cancer therapy. However, systemic administration of free anticancer agents is nonspecific and poses serious side effects. Hence, the present study aimed at developing mesoporous silica nanoparticle (MSN)-based targeted combination therapy of a Wnt signaling inhibitor, niclosamide (Nic), and a conventional anticancer agent, doxorubicin (Dox). The results demonstrated the reproducible synthesis of highly stable and monodispersed sub-100 nm spherical shaped NPs. In vitro cytotoxicity studies demonstrated that the individual drug formulations caused concentration-dependent cytotoxicity to all of the three breast cancer subtypes, with higher concentrations being more cytotoxic. Further, sequential and concurrent combination of Nic-loaded MSNs with Dox-loaded MSNs was synergistic and caused significantly enhanced death in all breast cancer subtypes. Quantification of the combinatorial efficacy suggested that multiple combinatorial pairs were synergistic in all of the breast cancer types for both (sequential and concurrent) treatment regimens. However, the extent of synergism varied between the two treatment regimens in different clinical subtypes of breast cancer. Overall, the combination of Nic-loaded MSNs with Dox-loaded MSNs holds promise to be developed as an efficient therapeutic option for breast cancer irrespective of the clinical subtype in both sequential and concurrent treatment regimens.

Niclosamide-Clay Intercalate Coated with Nonionic Polymer for Enhanced Bioavailability toward COVID-19 Treatment

Niclosamide (NIC), a conventional anthelmintic agent, is emerging as a repurposed drug for COVID-19 treatment. However, the clinical efficacy is very limited due to its low oral bioavailability resulting from its poor aqueous solubility. In the present study, a new hybrid drug delivery system made of NIC, montmorillonite (MMT), and Tween 60 is proposed to overcome this obstacle. At first, NIC molecules were immobilized into the interlayer space of cationic clay, MMT, to form NIC–MMT hybrids, which could enhance the solubility of NIC, and then the polymer surfactant, Tween 60, was further coated on the external surface of NIC–MMT to improve the release rate and the solubility of NIC and eventually the bioavailability under gastrointestinal condition when orally administered. Finally, we have performed an in vivo pharmacokinetic study to compare the oral bioavailability of NIC for the Tween 60-coated NIC–MMT hybrid with Yomesan^®, which is a commercially available NIC. Exceptionally, the Tween 60-coated NIC–MMT hybrid showed higher systemic exposure of NIC than Yomesan^®. Therefore, the present NIC–MMT–Tween 60 hybrid can be a potent NIC drug formulation with enhanced solubility and bioavailability in vivo for treating Covid-19.