Combinatorial Nanomedicine Made of Squalenoyl-Gemcitabine and Edelfosine for the Treatment of Osteosarcoma

State of the art in pediatric nanomedicines

In recent years, the continuous development of innovative nanopharmaceuticals is expanding their biomedical and clinical applications. Nanomedicines are being revolutionized to circumvent the limitations of unbound therapeutic agents as well as overcome barriers posed by biological interfaces at the cellular, organ, system, and microenvironment levels. In many ways, the use of nanoconfigured delivery systems has eased challenges associated with patient differences, and in our opinion, this forms the foundation for their potential usefulness in developing innovative medicines and diagnostics for special patient populations. Here, we present a comprehensive review of nanomedicines specifically designed and evaluated for disease management in the pediatric population. Typically, the pediatric population has distinguishing needs relative to those of adults majorly because of their constantly growing bodies and age-related physiological changes, which often need specialized drug formulation interventions to provide desirable therapeutic effects and outcomes. Besides, child-centric drug carriers have unique delivery routes, dosing flexibility, organoleptic properties (e.g., taste, flavor), and caregiver requirements that are often not met by traditional formulations and can impact adherence to therapy. Engineering pediatric medicines as nanoconfigured structures can potentially resolve these limitations stemming from traditional drug carriers because of their unique capabilities. Consequently, researchers from different specialties relentlessly and creatively investigate the usefulness of nanomedicines for pediatric disease management as extensively captured in this compilation. Some examples of nanomedicines covered include nanoparticles, liposomes, and nanomicelles for cancer; solid lipid and lipid-based nanostructured carriers for hypertension; self-nanoemulsifying lipid-based systems and niosomes for infections; and nanocapsules for asthma pharmacotherapy.

Gemcitabine-Vitamin E Prodrug-Loaded Micelles for Pancreatic Cancer Therapy

Pancreatic cancer (PC) is an aggressive cancer subtype presenting unmet clinical challenges. Conventional chemotherapy, which includes antimetabolite gemcitabine (GEM), is seriously undermined by a short half-life, its lack of targeting ability, and systemic toxicity. GEM incorporation in self-assembled nanosystems is still underexplored due to GEM's hydrophilicity which hinders efficient encapsulation. We hypothesized that vitamin E succinate-GEM prodrug (VES-GEM conjugate) combines hydrophobicity and multifunctionalities that can facilitate the development of Pluronic® F68 and Pluronic® F127 micelle-based nanocarriers, improving the therapeutic potential of GEM. Pluronic® F68/VES-GEM and Pluronic® F127/VES-GEM micelles covering a wide range of molar ratios were prepared by solvent evaporation applying different purification methods, and characterized regarding size, charge, polydispersity index, morphology, and encapsulation. Moreover, the effect of sonication and ultrasonication and the influence of a co-surfactant were explored together with drug release, stability, blood compatibility, efficacy against tumour cells, and cell uptake. The VES-GEM conjugate-loaded micelles showed acceptable size and high encapsulation efficiency (>95%) following an excipient reduction rationale. Pluronic® F127/VES-GEM micelles evidenced a superior VES-GEM release profile (cumulative release > 50%, pH = 7.4), stability, cell growth inhibition (<50% cell viability for 100 µM VES-GEM), blood compatibility, and extensive cell internalization, and therefore represent a promising approach to leveraging the efficacy and safety of GEM for PC-targeted therapies.

ARHGAP44 expression is associated with the metastasis of osteosarcoma and is a promising prognostic biomarker

Osteosarcoma (OS) is the most domain primary malignant bone tumor. Treatment resistances and metastases result in a decreasing 5-year overall survival rate of OS. However, Rho GTPase-activating protein 44 (ARHGAP44) has not been well studied in OS. The OS patient data were obtained from Therapeutically Applicable Research to Generate Effective Treatments and Gene Expression Omnibus databases. We utilized Survival and Survminer package for survival analysis based on Kaplan-Meier method. The association between ARHGAP44 expression with the prognosis of OS was determined by Wilcoxon rank-sum test and multivariate Cox regression analysis. The real-time polymerase chain reaction and western blotting were conducted to validate the results. Gene set enrichment analysis was done to find significant Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The OS sample ARHGAP44 expression level was significantly higher than that in normal samples, which was validated in cell lines. High ARHGAP44 expression was associated with metastasis of OS. The OS patients with high ARHGAP44 expression had worse prognosis compared with low ARHGAP44 expression OS patients. In total, 10 KEGG pathways significantly activated in high ARHGAP44 expression OS patients, such as Hedgehog signaling pathway, Steroid biosynthesis, and so on. In summary, high ARHGAP44 expression was closely correlated with the metastasis and poor prognosis of OS. ARHGAP44 was a potential prognostic biomarker for OS.

Recent and Ongoing Research into Metastatic Osteosarcoma Treatments

The survival rate for metastatic osteosarcoma has not improved for several decades, since the introduction and refinement of chemotherapy as a treatment in addition to surgery. Over two thirds of metastatic osteosarcoma patients, many of whom are children or adolescents, fail to exhibit durable responses and succumb to their disease. Concerted efforts have been made to increase survival rates through identification of candidate therapies via animal studies and early phase trials of novel treatments, but unfortunately, this work has produced negligible improvements to the survival rate for metastatic osteosarcoma patients. This review summarizes data from clinical trials of metastatic osteosarcoma therapies as well as pre-clinical studies that report efficacy of novel drugs against metastatic osteosarcoma in vivo. Considerations regarding the design of animal studies and clinical trials to improve survival outcomes for metastatic osteosarcoma patients are also discussed.

Bone Marrow Mesenchymal Stem Cells-Derived Extracellular Vesicles Promote Proliferation, Invasion and Migration of Osteosarcoma Cells via the lncRNA MALAT1/miR-143/NRSN2/Wnt/β-Catenin Axis

Introduction

Osteosarcoma is a malignant primary bone tumor. Bone marrow-derived mesenchymal stem cells-derived extracellular vesicles (BMSC-EVs) bear repair function for bone and cartilage. This study investigated the mechanism of BMSC-EVs in osteosarcoma cell proliferation, migration and invasion.

Methods

BMSC-EVs were isolated and identified. The effects of different concentrations of EVs on osteosarcoma cell proliferation, migration and invasion were evaluated. LncRNA MALAT1 expression in osteosarcoma cells was detected. BMSCs were transfected with si-MALAT1 or si-NC. The binding relationships between MALAT1 and miR-143, and miR-143 and NRSN2 were verified. Levels of NRSN2 and Wnt/β-catenin pathway key proteins were detected. miR-143 mimic was transfected into EVs-treated osteosarcoma cells. Nude mice were injected with MG63 cells to verify the effect of EVs on osteosarcoma growth in vivo.

Results

BMSC-EVs facilitated proliferation, invasion and migration of osteosarcoma cells. BMSC-EVs carried MALAT1 into osteosarcoma cells. BMSC-EVs-treated osteosarcoma cells showed increased MALAT1 and NRSN2 expressions, decreased miR-143 expression, and activated Wnt/β-catenin pathway. miR-143 mimic or si-MALAT1 reversed the effects of BMSC-EVs on osteosarcoma cells. In vivo experiment confirmed that BMSC-EVs promoted tumor growth in nude mice.

Discussion

BMSC-EVs promoted proliferation, invasion and migration of osteosarcoma cells via the MALAT1/miR-143/NRSN2/Wnt/β-catenin axis. This study might offer new insights into osteosarcoma management.