Nucleolin-Targeting AS1411 Aptamer-Conjugated Nanospheres for Targeted Treatment of Glioblastoma.

Post-operative chemotherapy is still required for the treatment of glioblastoma (GBM), for which nanocarrier-based drug delivery has been identified as one of the most effective methods. However, the blood-brain barrier (BBB) and non-specific delivery to non-tumor tissues can significantly limit drug accumulation in tumor tissues and cause damage to nearby normal tissues. This study describes a targeted cancer therapy approach that uses AS1411 aptamer-conjugated nanospheres (100-300 nm in size) loaded with doxorubicin (Dox) to selectively identify tumor cells overexpressing nucleolin (NCL) proteins. The study demonstrates that the active target model, which employs aptamer-mediated drug delivery, is more effective than non-specific enhanced permeability and maintenance (EPR)-mediated delivery and passive drug delivery in improving drug penetration and maintenance in tumor cells. Additionally, the study reveals the potential for anti-cancer effects through 3D spheroidal and in vivo GBM xenograft models. The DNA-protein hybrid nanospheres utilized in this study offer numerous benefits, such as efficient synthesis, structural stability, high drug loading, dye labeling, biocompatibility, and biodegradability. When combined with nanospheres, the 1411 aptamer has been shown to be an effective drug delivery carrier allowing for the precise targeting of tumors. This combination has the potential to produce anti-tumor effects in the active targeted therapy of GBM.

Lower Plasma Amyloid Beta - 42 Levels Associated With Worse Survival in Patients With Glioma.

BACKGROUND/AIM: Glioma is often refractory. The accumulation of amyloid beta (Aß) in the brain is commonly associated with Alzheimer's disease (AD), but there are studies suggesting that Aß has tumor suppressor potential. The aim of this study was to identify a novel, non-invasive candidate biomarker for histological prediction and prognostic assessment of glioma. PATIENTS AND METHODS: Serum was prepared from blood samples collected preoperatively from 48 patients with WHO grade II-IV glioma between October 2004 and December 2017 at a single tertiary institution. The concentration of Aß42 was measured using the SMCxPRO immunoassay (Merck). The clinical and histological characteristics of the patients, including molecular subtypes, were reviewed. RESULTS: The mean age of the patients was 52.2±12.5 years. The mean value of serum Aß42 concentration was 7.6±7.8 pg/ml in the anaplastic astrocytoma (WHO grade III) group and 6.4±6.5 pg/ml in the glioblastoma multiforme (WHO grade IV) group. The Negative epidermal growth factor receptor (EGFR) expression was associated with higher serum Aß42 levels (p=0.020). Kaplan-Meier analysis demonstrated that patients with high serum Aß42 (>11.78 pg/ml) had significantly longer progression-free survival (PFS) (p=0.038) and overall survival (OS) (p=0.018). CONCLUSION: This study investigated serum Aß42 levels as a potential biomarker for glioma. The results showed that low serum Aß42 levels were associated with EGFR expression and poor PFS and OS. Overall, these findings suggest a potential role of Aß42 as a prognostic marker in astrocytomas.

Effect of temperature, pH, and NaCl on the inactivation kinetics of murine norovirus.

We investigated the resistance of murine norovirus (MNV) and coliphage MS2, a culturable human norovirus surrogate, to temperature, salt, and pH. Virus inactivation was measured by plaque, real-time TaqMan reverse transcription (RT) PCR, and long-template RT-PCR assays. Both MNV and MS2 were rapidly inactivated at temperatures above 60°C. Similarly, MNV tolerated low salt concentrations (0.3% NaCl) to a greater degree than high salt concentrations (3.3 to 6.3% NaCl). MNV was relatively resistant to strong acidic conditions (pH 2) and was more tolerant of slightly acidic (pH 4) or neutral (pH 7) conditions. In contrast, MS2 was resistant to high salinity. Overall, temperature had a greater effect on infectivity than salt or low pH. Additionally, temperature and low pH had a synergistic effect on MNV infectivity. Both real-time and long-template RT-PCR assays significantly underestimated the inactivation by temperature, salt, and pH. The inactivation kinetics of both MNV and MS2 under various environmental conditions gave a good fit by the Weibull model (R² > 0.9). This study suggests both the capacity of infectious human norovirus to persist in the face of various environmental conditions and its sensitivity to high temperatures, which may provide a mechanism of protection against this virus.