Development of a super-hydrophilic anaerobic tube for the optimization of platelet-rich fibrin.

Horizontal platelet-rich fibrin (H-PRF) contains a variety of bioactive growth factors and cytokines that play a key role in the process of tissue healing and regeneration. The blood collection tubes used to produce Solid-PRF (plasmatrix (PM) tubes) have previously been shown to have a great impact on the morphology, strength and composition of the final H-PRF clot. Therefore, modification to PM tubes is an important step toward the future optimization of PRF. To this end, we innovatively modified the inner wall surface of the PM tubes with plasma and adjusted the gas environment inside the PM tubes to prepare super-hydrophilic anaerobic plasmatrix tubes (SHAP tubes). It was made anaerobic for the preparation of H-PRF with the aim of improving mechanical strength and bioactivity. The findings demonstrated that an anaerobic environment stimulated platelet activation within the PRF tubes. After compression, the prepared H-PRF membrane formed a fibrous cross-linked network with high fracture strength, ideal degradation characteristics, in addition to a significant increase in size. Thereafter, the H-PRF membranes prepared by the SHAP tubes significantly promoted collagen synthesis of gingival fibroblast and the mineralization of osteoblasts while maintaining excellent biocompatibility, and advantageous antibacterial properties. In conclusion, the newly modified PRF tubes had better platelet activation properties leading to better mechanical strength, a longer degradation period, and better regenerative properties in oral cell types including gingival fibroblast and alveolar osteoblasts. It also improves the success rate of H-PRF preparation in patients with coagulation dysfunction and expands the clinical application scenario.

Why was the study done?   Direct anaerobic environment effects on fibrin formation have been insufficiently studied.The effect of hydrophilic change caused by nitrogen plasma treatment on H-PRF coagulation has not been fully studied.Optimal preparation of H-PRF in patients with poor coagulation function was needed in clinical application.What is new?  The coagulation of H-PRF correlated with the level of dissolved oxygen concentrations. Anaerobic environment significantly accelerates fibrin formation and platelet activation.Nitrogen plasma treatment can remarkably enhance the hydrophilicity of the inner surface of glass blood collecting tubes, thereby promoting the activation of platelets and the formation of fibrin network.The H-PRF prepared in the tubes with anaerobic environment and hydrophilic surface showed high fracture strength, promoted collagen synthesis of gingival fibroblast and the mineralization of osteoblasts.What is the impact?  The work is aimed at developing super-hydrophilic anaerobic plasmatrix tubes (SHAP tubes) for studying gas environment and hydrophilicity participation in fibrin formation in H-PRF preparation and investigating the influence of platelet activation in the anaerobic environment.This study provides a successful trial to convert the physiological process into biotechnological application. The SHAP tubes proposed within this article was an effective versatile H-PRF preparation device, which provided a promising alternative for tissue engineering.

Androgen receptor promotes oral squamous cell carcinoma cell migration by increasing EGFR phosphorylation.

Objectives: This study is aimed to investigate the role of androgen receptor (AR) in regulating oral squamous cell carcinoma (OSCC) cells migration. Materials and methods: Tumors from 23 patients with OSCC and five OSCC cell lines were used for analyzing AR expression. The effects of AR agonist and antagonist were used to examine the role of AR in regulating the migration of OSCC cells. Results: Ten of 23 tumors from patients with OSCC were AR positive. There was no significant difference in total EGFR (tEGFR) expression between AR-positive tumors and AR-negative tumors. However, the expression of phosphorylated EGFR (pEGFR) in AR-positive tumors was significantly higher than that in AR-negative tumors (p<0.01). Stimulation of AR by dihydrotestosterone in SCC9 (AR-positive OSCC cell) caused an increase in pEGFR and pAKT expression and promoted cell migration without changed tEGFR expression, whereas treatment with bicalutamide led to a decrement in pEGFR expression and pAKT and inhibited cell migration. No effects were found in SCC25 cell line (AR-negative) either treated by dihydrotestosterone or bicalutamide. Furthermore, SCC9 cell line treated by EGF or cetuximab (EGFR inhibitor) significantly promoted or inhibited cell migration. Conclusion: Our data indicate that OSSC tumors and OSCC cell lines express AR which is critical for promoting cell migration by increasing EGFR phosphorylation.