Injectable hydrogel encapsulating Cu2MnS2 nanoplates for photothermal therapy against breast cancer.

BACKGROUND: In order to explore the possibility of treating breast cancer by local photo-therapy, a photothermal agents loaded in situ hydrogel was established. In detail, The Cu2MnS2 nanoplates were prepared by one-pot synthesis and, the thermosensitive Pluronic F127 was used as the hydrogel matrix. The Cu2MnS2 nanoplates and the hydrogel were characterized by morphous, particle size, serum stability, photothermal performance upon repeated 808 nm laser irradiation as well as the rheology features. The therapeutic effects of the Cu2MnS2 nanoplates and the hydrogel were evaluated qualitatively and quantitatively in 4T1 mouse breast cancer cells. The retention, photothermal efficacy, therapeutic effects and systemic toxicity of the hydrogel were assessed in tumor bearing mouse model. RESULTS: The Cu2MnS2 nanoplates with a diameter of about 35 nm exhibited satisfying serum stability, photo-heat conversion ability and repeated laser exposure stability. The hydrogel encapsulation did not negatively influence the above features of the photothermal agent. The nanoplates loaded in situ hydrogel shows a phase transition at body temperature and, as a result, a long retention in vivo. CONCLUSIONS: The photothermal agent embedded hydrogel played a promising photothermal therapeutic effects in tumor bearing mouse model with low systemic toxicity after peritumoral administration.

Activatable unsaturated liposomes increase lipid peroxide of cell membrane and inhibit tumor growth.

The cancer chemodynamic therapy based on the Fenton reaction has been attracting more and more attention. However, the performance of the Fenton reaction is restricted by the unsuitable physiological pH value and inadequate H2O2 content in the tumor microenvironment (TME). In this study, we proposed a novel method of inducing lipid peroxide (LPO) of the cancer cell membrane, whose performance is not limited by the pH value and H2O2 in the TME. The activatable LPO-inducing liposomes were constructed by encapsulating Fe3+-containing compound ferric ammonium citrate (FC) in the unsaturated soybean phospholipids (SPC). It was found that the FC could be reduced by the overexpressed glutathione (GSH) in the TME and produce iron redox couple. The Fe3+/Fe2+ mediated the peroxidation of the unsaturated SPC and induced the LPO in the cancer cells. Finally, LPO accumulation led to cancer cell death and tumor growth inhibition. Furthermore, the activatable liposomes did not damage healthy tissues because of the low GSH content in normal tissues and the GSH-triggered activation of the nanocarrier. Together, our findings revealed that FC-SPC-lipo displayed excellent anti-tumor performance and its therapeutic effects are less influenced by the TME, compared with the traditional ferroptosis.

[Role of autophagy in the pathogenesis of periodontitis].

Periodontitis is a chronic inflammatory disease of periodontal tissues initiated by oral biofilm. Cellular autophagy is an effective weapon against bacterial infection. Recent studies have shown that autophagy not only promotes the removal of bacteria and toxins from infected cells, but also helps to suppress the inflammatory response to maintain the homeostasis of intracellular environment, which is closely related to the development of periodontitis. Here, we reviewed the relationship between autophagy and periodontitis from three aspects: the interactions between autophagy and periodontal pathogen infection, the regulation of autophagy and immune inflammatory responses, and the relationship between autophagy and alveolar bone metabolism. We aim to provide ideas for further study on the mechanisms of autophagy and periodontitis, and ultimately contribute to a better prevention and treatment of periodontitis.

Tri-block polymer with interfacial layer formation ability and its use in maintaining supersaturated drug solution after dissolution of solid dispersions.

BACKGROUND: Maintaining a supersaturated drug solution after the dissolution of the solid dispersions of water insoluble drugs continues to be a great challenge and is important to the oral bioavailability enhancement of hardly soluble drugs. METHODS: Nimodipine solid dispersions were prepared by hot-melt extrusion and a special tri-block polymer was employed as a co-carrier. The solid dispersions were characterized by modulated differential scanning calorimetry, transmission electron microscopy, hydrogen-nuclear magnetic resonance and so on. RESULTS: The tri-block polymer was able to inhibit the formation of drug crystals after dissolution of the solid dispersions. Due to the unique interfacial layer formation ability of the tri-block polymer, a special drug loading micelle which encapsulated the compound and the hydrophobic fragments of the copolymers appeared in the release media. The tri-block polymer was composed of a hydrophilic part forming the shell of micelles, a hydrophobic part shaping the core of micelles, and a special intermediate hydrophilicity part constructing the interfacial layer of micelles. CONCLUSION: The tri-block polymer was not only able to stabilize the supersaturated drug solution of solid dispersions to enhance the oral bioavailability of hardly soluble drugs, but is also a potential candidate to construct micelles for systemic administration, due to the good compatibility and organic solvents free micelle formation procedure.

Use of PEG-asparaginase in newly diagnosed adults with standard-risk acute lymphoblastic leukemia compared with E. coli-asparaginase: a retrospective single-center study.

Acute lymphoblastic leukemia (ALL) is a heterogeneous disease, and the long-term survival varies with different ages. We performed a retrospective analysis of 122 newly diagnosed adults with standard-risk ALL treated with Escherichia coli asparaginase (E. coli-asparaginase, n = 50) and polyethylene glycol-conjugated asparaginase (PEG-asparaginase, n = 72). No treatment-related mortality (TRM) occurred in the E. coli-asparaginase group, and 3 TRM events occurred in the PEG-asparaginase group without relation to asparaginase. In addition, 22 (44.0%) and 48 (66.7%) patients achieved a complete response (CR) on day 14 in the E. coli-asparaginase and PEG-asparaginase groups, respectively (P = 0.032). No different 5-year event-free survival (EFS) or overall survival (OS) rate (P = 0.632 and 0.769) was observed. Multivariate analysis revealed later CR (P = 0.008) and older age (P = 0.049) as adverse prognostic factors for both EFS and OS. In addition, we specifically monitored the known adverse effects of asparaginase, and no asparaginase-related death was observed. Allergy occurred in 9 patients using E. coli-asparaginase, and no patient in the PEG-asparaginase group suffered from allergies (P < 0.001). The incidence of other asparaginase-related toxicities was similar. We conclude that PEG-asparaginase can be safely and effectively used as asparaginase in adults with newly diagnosed standard-risk ALL.

Efficacy of combined gemcitabine, oxaliplatin and pegaspargase (P-gemox regimen) in patients with newly diagnosed advanced-stage or relapsed/refractory extranodal NK/T-cell lymphoma.

Extranodal natural killer/T-cell lymphoma (ENKTL) is an aggressive neoplasm with a poor outcome. Asparaginase-based regimens are recommended for patients with advanced-stage or relapsed/refractory ENKTL. We retrospectively investigated the efficacy and toxicity of combined gemcitabine, oxaliplatin, and pegaspargase (P-gemox) in these patients. A total of 35 patients with newly diagnosed stage III-IV, relapsed or refractory ENKTL were treated with 2 to 8 cycles of P-gemox: gemcitabine (1250 mg/m2) and oxaliplatin (85 mg/m2) injected intravenously and pegaspargase (2500 IU/m2) injected intramuscularly on day 1 and repeated every 2 weeks. Upon completion of treatment, the overall response rate was 80.0%, with a complete response in 51.4% of patients. The 1-, 2- and 3- year progression-free survival rates were 45.0%, 38.6% and 38.6%, and overall survival rates were 76.8%, 64.7% and 64.7%, respectively. Patients who attained a complete response showed better progression-free survival than those without a complete response (p = 0.01). The major adverse effects were hematologic toxicity and liver dysfunction. Grade 3/4 leucopenia and neutropenia occurred in 40.0% of patients. No treatment-related deaths occurred. These results indicate the P-gemox regimen is a safe and effective treatment for patients with newly diagnosed advanced-stage or relapsed/refractory ENKTL. We anticipate future prospective trials will confirm the efficacy.