miR-379-5p regulates the proliferation, cell cycle, and cisplatin resistance of oral squamous cell carcinoma cells by targeting ROR1.

OBJECTIVE: To analyze the regulatory mechanism microRNA miR-379-5p in oral squamous cell carcinoma (OSCC). METHODS: We collected serum samples from patients with OSCC and examined the expression of miR-379-5p and receptor tyrosine kinase-like orphan receptor 1 (ROR1) by real-time polymerase chain reaction and western blot. OSCC cells were purchased for molecular research, cell multiplication was tested using the BrdU assay, cell cycle was tested using flow cytometry, and resistance to cisplatin (DDP) was assessed using the MTT assay. RESULTS: miR-379-5p expression was downregulated and ROR1 expression was upregulated in the serum of OSCC patients, and the area under the curve for OSCC identified by miR-379-5p and ROR1 was not less than 0.800. In the cell function test, overexpression of miR-379-5p could suppress the proliferation, cell cycle, and DDP resistance of OSCC cells. miR-379-5p could negatively regulate ROR1. Inhibition of ROR1 expression had a similar effect after the re-expression of miR-379-5p. Co-overexpression of miR-379-5p and ROR1 counteracted the above inhibitory effects on the proliferation, cell cycle, and DDP resistance of OSCC cells. CONCLUSION: miR-379-5p in OSCC regulates the proliferation, cell cycle, and DDP resistance of tumor cells by targeting ROR1.

Selective laser melted titanium implants play a positive role in early osseointegration in type 2 diabetes mellitus rats.

Success of dental implant is associated with the surface modification. To evaluate whether the selective laser melting-superfinished titanium (Ti6Al4V) implants have a better early osseointegration in type 2 diabetes mellitus rats compare to pure titanium implants and acid-etched treated (SLA) implants, we designed a screw-shaped implant which was batch-fabricated by selective laser melting (SLM). Then the implants were randomly inserted in tibias of rats with type 2 diabetes mellitus (T2DM). After surgical operation, the SLM group showed the best bone formation around the implants with the highest bone-implant contact rate among the three groups.Removal torque tests and histomorphological analyses all revealed a stronger connection between the bone because its good surface characteristics and mechanical properties. SLM implant may be a novel implant for T2DM patients.

Exendin­4 promotes osteogenic differentiation of adipose­derived stem cells and facilitates bone repair.

Inflammation­related bone defects pose a heavy burden on patients and orthopedic surgeons. Although stem­cell­based bone repair has developed rapidly, it is of great significance to characterize bio­active molecules that facilitate bone regeneration. It is reported that a glucagon­like peptide 1 receptor agonist, exendin­4, promoted bone regeneration mediated by the transplantation of adipose­derived stem cells in a metaphyseal defect mouse model of femur injury. However, the underlying mechanism is unclear. Bone imaging, immunohistochemistry real­time PCR and western blot analysis were used in the present study, and the results revealed that exendin­4 increased the transcription of the osteogenic differentiation­related genes and induced osteogenic differentiation in situ. Furthermore, the present data obtained from sorted adipose­derived stem cells revealed that exendin­4 promoted osteogenic differentiation and inhibited adipogenic differentiation in vitro. These findings indicated that exendin­4 facilitates osteogenic differentiation of transplanted adipose­derived stem cells for bone repair and illuminated clinical prospects of both adipose­derived stem cells and exendin­4 in stem­cell­based bone defect repair.

Simulated microgravity inhibits the viability and migration of glioma via FAK/RhoA/Rock and FAK/Nek2 signaling.

Due to excessive proliferation and metastasis, glioma is the most common primary tumor in the central nervous system. Previous reports show simulated microgravity (SMG) has the ability to inhibit the proliferation and migration of cancer. The aim of this study was to evaluate the viability and migration of U251 cells in SMG environment. SMG induced apoptosis of U251 cells. The FAK/RhoA/Rock and FAK/Nek2 signaling events were attenuated by SMG to destabilize actin cytoskeleton and centrosome disjunction, which caused G2/M arrest and inhibition of cell viability and migration. Overexpressed FAK reversed SMG-induced inhibition of viability and migration in U251 cells, which increased downstream RhoA/Rock signaling and Nek2. These findings reveal novel pathways of FAK/RhoA/Rock and FAK/Nek2 are affected by SMG, and highlight an opportunity to expand therapeutic options in a variety of settings.

Effects of irradiation on osteoblast-like cells on different titanium surfaces in vitro.

The aim of this study was to investigate the effects of irradiation on adhesion ability, proliferation, and differentiation of MC3T3-E1 cells on microarc oxidation (MAO) titanium surfaces and polished titanium (PT) surfaces. MC3T3-E1 cells were exposed to a single dose at 2, 4, 6, 8, or 10 Gy using a (60) Co source, with tissue culture polystyrene plates chosen as controls. On all surfaces, irradiation resulted in a dose-dependent decrease in cellular proliferation. At 4 Gy dose, the cell proliferation of cells decreased by 17.8% on MAO and 18.6% on PT surfaces, respectively, compared with nonirradiated controls. Cells exposed to 8 Gy dose showed significant inhibition in collagen secretion and osteogenesis-related genes expression (OSX, COL-Iα1, and OCN). In contrast, irradiation increased cell adhesion to three surfaces dose dependently. It was also demonstrated that cells on MAO surface showed higher adhesion and collagen secretion than on PT surface at different radiation doses. This study revealed the effects of irradiation on osteoblasts in vitro on two titanium surfaces. MAO surface could be used in dental implants in irradiated bone due to enhanced adhesion ability and collagen secretion in osteoblasts.

The role of the lateral pterygoid muscle in the sagittal fracture of mandibular condyle (SFMC) healing process.

The aim of this study was to examine the role of the lateral peterygoid muscle in the reconstruction of the shape of the condyle during healing of a sagittal fracture of the mandibular condyle. Twenty adult sheep were divided into 2 groups: all had a unilateral operation on the right side when the anterior and posterior attachments of the discs were cut, and an oblique vertical osteotomy was made from the lateral pole of the condyle to the medial side of the condylar neck. Ten sheep had the lateral pterygoid muscle cut, and the other 10 sheep did not. Sheep were killed at 4 weeks (n=2 from each group), 12 weeks (n=4), and 24 weeks (n=4) postoperatively. Computed tomograms (CT) were taken before and after operations. We dissected the joints, and recorded with the naked eye the shape, degree of erosion, and amount of calcification of the temporomandibular joint (TMJ). In the group in which the lateral peterygoid muscle had not been cut the joints showed overgrowth of new bone and more advanced ankylosis. Our results show that the lateral pterygoid muscle plays an important part in reconstructing the shape of the condyle during the healing of a sagittal fracture of the mandibular condyle, and combined with the dislocated and damaged disc is an important factor in the aetiology of traumatic ankylosis of the TMJ.