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Since the number of prognostic and predictive neuro-oncologic genetic markers is steadily increasing, a comprehensive analysis of the molecular techniques used to examine neuro-oncology samples is vastly required. Molecular analysis and profiling of brain malignancies result in improved diagnostic accuracy, target identification, and predictive prognosis. Application of high-throughput molecular approaches, such as next generation sequencing (NGS), to analyze brain tumors has provided a large amount of molecular information. In the clinical practice, the application of NGS has been increased, which has consequently improved the treatment option for brain cancer as well as other types of malignancies. Target therapy has recently become one of the most promising treatment options for various tumors, especially brain tumors. In this review, we provided and summarized high-throughput genomic studies, such as NGS technique, that could independently identify the integrated management and diagnosis of primary human brain tumors across a variety of entities with pathognomonic genetic alterations.

Alginate scaffolds are extensively used in bone and cartilage tissue engineering because of their chemical similarity to the extracellular matrix. However, for the successful replacement of hard tissue, the properties of alginate scaffolds should be tailored. In this study, for the first time, we optimized the porosity, degradation rate, mechanical, and osteogenic properties of alginate scaffolds by the freeze-drying method. The freeze-drying method was used to prepare different concentrations of alginate scaffolds (4, 8, and 16% (w/v)). Their porosity, mechanical properties, surface-wetting behavior, and osteogenic properties were characterized. The results showed that the 8% (w/v) alginate scaffold had an interconnected porosity of about 80%, a hydrophilic surface with a contact angle of water on the surface of 39o ± 0.56, and compressive strength of 2.7 MPa. This concentration of alginate also showed the degradation rate of 70% in Dulbecco’s Modified Eagle’s Medium (DMEM) with fetal bovine serum. The periodontal ligament stem cells culture results confirmed that the 8% alginate scaffold had good biocompatibility and cell differentiation ability and it could enhance cell ingrowth and attachment. These results showed that the modified 8% (w/v) alginate scaffold is a good candidate in cartilage and bone tissue replacement.

The hydrogel efficacy of taurine-loaded chitosan nanoparticle/alginate hydrogel was investigated for controlled release of the taurine substrate, which is known as an antioxidative drug. The composition of the fabricated hydrogels was explored by Fourier-transform infrared spectroscopy. The swelling ability and degradation rate of hydrogels were also analyzed in phosphate-buffered saline at the physiological condition and alginate lyase for a period of 21 days. Moreover, morphologies and structure of hydrogels and cells were determined using a scanning electron microscope. The possible cytotoxicity of the fabricated hydrogel was carried out by seeding endometrial stem cells on hydrogels. The results demonstrated that hydrogel of chitosan nanoparticle/alginate hydrogel successfully controlled the release of taurine. We observed that the chitosan nanoparticle/alginate hydrogel possessed adjust swelling ability and degradation rate as compared to neat alginate hydrogel. The results proved that the chitosan nanoparticle/alginate hydrogel is non-cytotoxic and could be utilized as a promising composition in tissue engineering and drug delivery systems.

Porous alginate/polyvinyl alcohol hybrid scaffolds have been extensively used in cartilage, bone, and dental tissue substitute applications. However, its mechanical and osteogenesis properties are not good enough to meet the requirement for use in hard tissues repair applications. In this study, to achieve the best mechanical and physical properties, we carried out the cross-linking of PVA physically and alginate chemically. Hydroxyapatite nanoparticles (nHA), the important component of hard tissues, was added to the hydrogel to improve its mechanical properties and osteoconductivity. The results showed that the fabricated alginate/polyvinyl alcohol-nHA scaffold has around 81% interconnected porosity, hydrophilic surface with the contact angle of water on the surface in the range of 38 ± 0.29°, 3.51 MPa compressive strength, and a degradation rate of 71%. The periodontal ligament stem cells (PDLSCs) culture results showed that both fabricated alginate/polyvinyl alcohol hybrid scaffolds with and without nHA had good cell attachment ability and could promote PDLSCs ingrowth. The real-time RT-PCR assay showed that the presence of nHA in the alginate/polyvinyl alcohol hybrid scaffold could significantly accelerate the expression of specific markers of pre- and mature osteoblast stages such as osteocalcin, alkaline phosphate, and osteopontin genes. These results showed that alginate/polyvinyl alcohol hybrid scaffolds with hydroxyapatite nanoparticles can be used in bone and dental substitute applications as osteoconductive and reinforcement components.

The efficacy of Alginate/ Polyvinyl alcohol/ Hydroxyapatite nanopowders (Alg/PVA/HANPs) mats was investigated for increasing periodontal ligament stem cells (PDLSCs) differentiation into the osteoblast cells. The Alg/PVA/HANPs nanofibers were fabricated through electospinning process and following ionic crosslinking of Ca+2 and glutaraldehyde crosslinkers. The physical features of mats and expression of osteoblast cell markers were evaluated. Results showed the diameter of nanofiber increases with decreasing the incorporation of HANPs in Alg/PVA nanofiber. According to MTT assay the viability of cells on scaffolds are better in the all of groups, so the scaffolds were not toxic for the cultured cells. The osteogenic culture media appropriately enhanced osteopontin and osteocalcin markers. Furthermore, in vitro study indicated that the Alg/PVA/HANPs nanofiber provided a suitable three-dimensional structure for osteoblast cells differentiation. Thus, the Alg/PVA/HANPs scaffold can be recommended for in bone repair.