Natural killer (NK)-cell-based immunotherapy has been reported to have promising prospects in the treatment of non-small cell lung cancer, one of the most common malignancies in the world. It has been proven that higher the NK cell infiltration into the tumor, the better is the curative effect. Therefore, it would be beneficial to develop a method that increases NK cell recruitment and infiltration into the tumor site. The purpose of this study was to establish an immune-cell delivery system for clear lung cancer cells based on magnetic nanoparticle (NP)-labeled NK cells that can be accumulated at the tumor site by placing a tiny external magnetic device inside animals. We developed superparamagnetic iron oxide NPs consisting of a magnetic Fe₃O₄ core and a shell of polydopamine (PDA) for magnetic targeting therapy. Fe₃O₄@PDA NPs possess favorable physiological stability and biocompatibility that facilitate their active uptake by NK cells. The biology of NK cells was not affected by the presence of NPs. In vitro and in vivo studies showed that Fe₃O₄@PDA NP-labeled NK cells significantly inhibited tumor growth and reduced the expression of Ki-67 and increased the apoptosis of A549 cancer cells. H&E staining showed Fe₃O₄@PDA NP-labeled NK cells, under a magnetic field, had higher intra-tumoral iron density and increased accumulation of CD56⁺ NK cells. Our results suggest that Fe₃O₄@PDA NPs are a promising magnetic nanomaterial that can manipulate immune cells, thereby inhibiting tumor growth.

Purpose: Polydopamine-coated branched Au–Ag nanoparticles (Au–Ag@PDA NPs) exhibit good structural stability, biocompatibility, and photothermal performance, along with potential anticancer efficacy. Here, we investigated the cytotoxicity of Au–Ag@PDA NPs against human bladder cancer cells (T24 cells) in vitro and in vivo, as well as the underlying molecular mechanisms of photothermal therapy-induced T24 cell death. Materials and methods: T24 cells were treated with different doses of Au–Ag@PDA NPs followed by 808 nm laser irradiation, and the effects on cell proliferation, cell cycle, apoptosis, and autophagy were analyzed. To confirm the mechanisms of inhibition, real-time PCR and Western blot analysis were used to evaluate markers of cell cycle, apoptosis, autophagy, and the AKT/ERK signaling pathway. Moreover, we evaluated the effects of the treatment on mitochondrial membrane potential and ROS generation to confirm the underlying mechanisms of inhibition. Finally, we tested the T24 tumor inhibitory effects of Au–Ag@PDA NPs plus laser irradiation in vivo using a xenograft mouse model. Results: Au–Ag@PDA NPs, with appropriate laser irradiation, dramatically inhibited the proliferation of T24 cells, altered the cell cycle distribution by increasing the proportion of cells in the S phase, induced cell apoptosis by activating the mitochondria-mediated intrinsic pathway, and triggered a robust autophagy response in T24 cells. Moreover, Au–Ag@PDA NPs decreased the expression of phosphorylated AKT and ERK and promoted the production of ROS that function upstream of apoptosis and autophagy. In addition, Au–Ag@PDA NP-mediated photothermolysis also significantly suppressed tumor growth in vivo. Conclusion: This preclinical study can provide a mechanistic basis for Au–Ag@PDA NP-mediated photothermal therapy toward promotion of this method in the clinical treatment of bladder cancer.

Iron oxide nanoparticles promote the migration of mesenchymal stem cells to injury sites Xiuying Li,1,* Zhenhong Wei,1,* Huiying Lv,1 Liya Wu,1 Yingnan Cui,1 Hua Yao,1 Jing Li,1 Hao Zhang,2 Bai Yang,2 Jinlan Jiang1 1Scientific Research Center, China-Japan Union Hospital of Jilin University, Changchun, Jilin, People’s Republic of China; 2State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin, People’s Republic of China *These authors contributed equally to this work Background: Developing new methods to deliver cells to the injured tissue is a critical factor in translating cell therapeutics research into clinical use; therefore, there is a need for improved cell homing capabilities. Materials and methods: In this study, we demonstrated the effects of labeling rat bone marrow-derived mesenchymal stem cells (MSCs) with fabricated polydopamine (PDA)-capped Fe3O4 (Fe3O4@PDA) superparticles employing preassembled Fe3O4 nanoparticles as the cores. Results: We found that the Fe3O4@PDA composite superparticles exhibited no adverse effects on MSC characteristics. Moreover, iron oxide nanoparticles increased the number of MSCs in the S-phase, their proliferation index and migration ability, and their secretion of vascular endothelial growth factor relative to unlabeled MSCs. Interestingly, nanoparticles not only promoted the expression of C-X-C chemokine receptor 4 but also increased the expression of the migration-related proteins c-Met and C-C motif chemokine receptor 1, which has not been reported previously. Furthermore, the MSC-loaded nanoparticles exhibited improved homing and anti-inflammatory abilities in the absence of external magnetic fields in vivo. Conclusion: These results indicated that iron oxide nanoparticles rendered MSCs more favorable for use in injury treatment with no negative effects on MSC properties, suggesting their potential clinical efficacy. Keywords: mesenchymal stem cells, migration, Fe3O4 nanoparticles, polydopamine

A mitochondria-targeted and exocytosis inhibition strategy of polydopamine-coated inorganic nanoparticles for enhanced papillary thyroid cancer therapy is demonstrated.

The Fe ₃ O ₄ @PDA NPs enhanced the recruitment of MSCs and improved the anti-inflammatory and healing ability compared with the MSC treatment alone.

Triple-negative breast cancer (TNBC) exhibits high recurrence and mortality rates because of the lack of effective treatment targets. Surgery and traditional chemotherapy are the primary treatment options. Immunotherapy shows high potential for treating various cancers but exhibits limited efficacy against TNBC as a monotherapy. Chemoimmunotherapy has broad prospects for applications for cancer treatment conferred through the synergistic immunomodulatory and anti-tumor effects of chemotherapy and immunotherapeutic strategies. However, improving the efficacy of synergistic therapy and reducing the side effects of multiple drugs remain to be the main challenges in chemoimmunotherapy against TNBC. Nanocarriers can target both cancer and immune cells, promote drug accumulation, and show minimal toxicity, making them ideal delivery systems for chemotherapeutic and immunotherapeutic agents. In this review, we introduce the immunomodulatory effects of chemotherapy and combined mechanisms of chemoimmunotherapy, followed by a summary of nanoparticle-mediated chemoimmunotherapeutic strategies used for treating TNBC. This up-to-date synthesis of relevant findings in the field merits contemplation, while considering avenues of investigation to enable advances in the field.