This study investigated the influence of surface wettability on competitive protein adsorption and the initial attachment of osteoblasts. A thin-film coating of hexamethyldisiloxane (HMDSO) and subsequent O(2)-plasma treatment was carried out on substrates with a mirror surface in order to create a wide range of wettabilities. The adsorption behavior of fibronectin (Fn) and albumin (Alb) in both individual and competitive mode, and the initial attachment of mouse osteoblastic cells (MC3T3-E1) over a wide range of wettabilities were investigated. The contact angle of HMDSO coatings without O(2)-plasma treatment against double-distilled water was more than 100 degrees, whereas it dramatically decreased after the O(2)-plasma treatment to almost 0 degrees, resulting in super-hydrophilicity. Individually, Fn adsorption showed a biphasic inclination, whereas Alb showed greater adsorption to hydrophobic surfaces. In the competitive mode, in a solution containing both Fn and Alb, Fn showed greater adsorption on hydrophilic surfaces, whereas Alb predominantly adsorbed on hydrophobic surfaces. The initial attachment of osteoblastic cells increased with an increase in surface wettability, in particular, on a super-hydrophilic surface, which correlated well with Fn adsorption in the competitive mode. These results suggest that Fn adsorption may be responsible for increasing cell adhesion on hydrophilic surfaces in a body fluid or culture media under physiological conditions.

Surface wettability is an important physicochemical property of biomaterials, and it would be more helpful for understanding this property if a wide range of wettability are employed. This study focused on the effect of surface wettability on fibroblast adhesion over a wide range of wettability using a single material without changing surface topography. Plasma polymerization with hexa methyldisiloxane followed by oxygen (O 2 ) plasma treatment was employed to modify the surfaces. The water contact angle of sample surfaces varied from 106 degrees (hydrophobicity) to almost 0 degrees (super-hydrophilicity). O 2 -functional groups were introduced on polymer surfaces during O 2 -plasma treatment. The cell attachment study confirmed that the more hydrophilic the surface, the more fibroblasts adhered in the initial stage that includes on super-hydrophilic surfaces. Cells spread much more widely on the hydrophilic surfaces than on the hydrophobic surfaces. There was no significant difference in fibroblast proliferation, but cell spreading was much greater on the hydrophilic surfaces. These findings suggest the importance of the surface wettability of biomaterials on initial cell attachment and spreading. The degree of wettability should be taken into account when a new biomaterial is to be employed. Further research of surface wettability on adhesive molecules is necessary for a better understanding of this property.

Abstract. Perineural invasion (PNI) is a striking biological behavior observed in salivary adenoid cystic carcinoma (SACC). The present study was designed to establish a co-culture model of SACC cells with Schwann cells (SCs), and then study epithelial-mesenchymal transition (EMT) and the Schwann-like differentiation of SACC cells to investigate the likely molecular mechanism of PNI. The co-culture models of SCs with tumor cells (SACC-83, SACC-LM and MEC-1) were established using a Transwell system. An elevated concentration of brain-derived neurotrophic factor (BDNF) was detected by ELISA assay in the co-cultured medium of the SACC-83 group and SACC-LM group rather than the MEC-1 group. The EMT process and Schwann-like differentiation in SACC-83 cells were analyzed by RT-PCR, western blotting, immunofluorescence, photography, and migration and perineural invasion assays. The SACC-83 cells under the co-culture condition with SCs changed to a mesenchymal morphology and had higher migration and invasion capabilities compared with the solely cultured SACC-83 cells, accompanied by the downregulation of E-cadherin and upregulation of N-cadherin and vimentin. The co-cultured SACC-83 cells also developed Schwann-like differentiation with increased expression of SC markers, S100A4 and GFAP. However, inhibition of tropomyosin-related kinase B (TrkB) by K252a markedly blocked these effects. Additionally, the expression and correlation of TrkB, E-cadherin and S100A4 were analyzed by immunohistochemistry in 187 primary SACC cases. The levels of TrkB and S100A4 expression were both positively associated with PNI in the SACC cases, while E-cadherin expression was negatively associated with PNI. Elevated expression of TrkB was significantly correlated with the downregulated expression of E-cadherin and the upregulated expression of S100A4 in the SACC cases. Our results suggest that SCs play a pivotal role in the PNI process by inducing the EMT process and the Schwann-like differentiation of SACC cells via the BDNF/TrkB axis. Interruption of the interreaction between SACC cells and SCs by targeting the BDNF/TrkB axis may be a potential strategy for anti-PNI therapy in SACC.

No abstract

Abstract:Periodontitis is an oral inflammatory disease that not only affects the integrity of local tooth-supporting tissues but also impacts systemic health. A compositional shift in oral microbiota has been considered as the main cause of periodontitis; however, the potential mechanism has not been fully defined. Herein, we investigated the role of CCAAT/enhancer-binding protein β (C/EBP β), a member of the C/EBP family of transcription factors, in human periodontal ligament cells (hPDLCs) exposed to Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS). RT-PCR and Western blotting analysis showed that the expression of C/EBP β was significantly increased in hPDLCs stimulated with LPS stimuli. Overexpression of C/EBP β by the recombinant adenoviral vector pAd/C/EBP β markedly increased the expression of the pro-inflammatory cytokines IL-6 and IL-8, and matrix metalloproteinases (MMP)-8 and -9 in hPDLCs in response to LPS. Furthermore, the activation of endoplasmic reticulum (ER) stress was confirmed in LPS-stimulated hPDLCs by measuring the expression of the ER stress marker molecules protein kinase-like ER kinase (PERK), eIF2α, GRP78/Bip, and C/EBP homologous protein (CHOP). The ER stress inhibitor salubrinal repressed, but inducer tunicamycin enhanced, the production of IL-6, IL-8, MMP-8, and MMP-9 in hPDLCs. Additionally, ER stress inducer tunicamycin significantly increased the expression level of C/EBP β in hPDLCs. Blocking of C/EBP β by siRNA resulted in a significant decrease in the secretion of IL-6 and IL-8 and expression of MMP-8 and MMP-9 induced by tunicamycin treatment in hPDLCs. Taken together, ER stress appears to play a regulatory role in the inflammatory response and extracellular matrix (ECM) degradation in hPDLCs in response to LPS stimuli by activating C/EBP β expression. This enhances our understanding of human periodontitis pathology.

Our aim was to establish a “nomogram” model to forecast the overall survival (OS) and cancer‐specific survival (CSS) of oral squamous cell carcinoma (OSCC) patients. The clinicopathological data for the 10,533 OSCC patients were collected from the Surveillance, Epidemiology and End Results (SEER) database. We used a credible random split‐sample method to divide 10,533 patients into two cohorts: 7046 patients in the modeling cohort and 3487 patients in the external validation cohort (split‐ratio = 2:1). The median follow‐up period was 32 months (1–119 months). We developed nomograms to predict 5‐ and 8‐year OS and CSS of OSCC patients with a Cox proportional hazards model. The precision of the nomograms was assessed by the concordance index (C‐index) and calibration curves through internal and external validation. The C‐indexes of internal validation regarding 5‐ and 8‐year OS and CSS were 0.762 and 0.783, respectively. In addition, the external validation's C‐indexes were 0.772 and 0.800. Based on a large‐sample analysis targeting the SEER database, we established two nomograms to predict long‐term OS and CSS for OSCC patients successfully, which can assist surgeons in developing a more effective therapeutic regimen and conducting personalized prognostic evaluations.

Human papillomavirus (HPV), the causal factor of cervical cancers, was closely linked to the etiology and prognosis of oropharyngeal squamous cell carcinoma (OPSCC), but its role in oral squamous cell carcinoma (OSCC) was unclear. In addition, few researches based on Chinese population were documented. Hence, we sought to investigate the relationship of HPV marker P16 protein to the clinicopathological parameters and survival of OPSCC and OSCC patients systematically to assess the influence of ethnic, regional difference on HPV susceptibility. Specimens from 93 OPSCC patients and 95 OSCC patients were recut, and P16 immunohistochemistry (IHC) was performed. Moreover, survival analysis was conducted to confirm the independent factors that influenced the prognosis. The P16 results were positive in 25.8% and 9.5% of patients with OPSCC and OSCC, respectively. The overall survival (OS) of HPV‐positive OPSCC patients was significantly longer than that of HPV‐negative OPSCC patients (P = 0.004). Conversely, statistical significance was not observed regarding the OS of OSCC patients (P = 0.343). Cox regression analysis indicated that T stage and P16 status were independent factors that affected the prognosis of OPSCC patients, and the smoking index influenced the prognosis of OSCC patients. Among OPSCC patients who received radiochemotherapy (RCT), HPV‐positive patients had a better survival rate than their HPV‐negative counterparts (P = 0.015). Conversely, no significant difference was observed between HPV‐positive and HPV‐negative OSCC patients who received RCT (P = 0.237). P16 is a credible surrogate by which to define HPV status. HPV expression had a favorable effect on OPSCC patients as opposed to their OSCC counterparts in this single center population‐based study.

Objective: The present study investigated the roles and underlying mechanism of CCL2/CCR2 axis in the interactions between tumor cells and tumor-associated macrophages (TAMs) during the progression of salivary adenoid cystic carcinoma (SACC). Methods: Immunohistochemical staining and survival analysis were performed to study the correlation and clinical value of CD68, CD163, CCL2, and CCR2 expression in SACC cases. CCL2 silencing by RNA interference and CCR2 blocking by CCR2 specific antagonist (RS504393) were performed. ELISA, qRT-PCR, western blot, immunofluorescence, flow cytometry, CCK8, scratch wound healing, and transwell assays were used to explore the functional roles and possible mechanism of CCL2/CCR2 axis in the interactions between SACC cells and TAMs. The effects of targeting TAMs by blocking the CCL2/CCR2 axis were investigated in a xenograft mice model with SACC cells. Results: The high infiltration of TAMs marked by CD68 and high infiltration of M2 TAMs marked by CD163 were significantly correlated with the expression of CCL2 and CCR2 in SACC tissues. Notably, the high infiltration of TAMs and the overexpression of CCL2 were obviously associated with the clinical progression and poor prognosis of SACC. SACC cells derived CCL2 could activate its receptor CCR2 expression in TAMs in vitro . The in vitro results further indicated that the SACC cells derived CCL2 was involved in the recruitment, M2 polarization, and GDNF expression of TAMs through the CCL2/CCR2 axis. Meanwhile, TAMs derived GDNF promoted the proliferation, migration, and invasion of SACC cells through the GDNF/p-RET pathway. Treating immunodeficient mice with the CCR2 antagonist (RS504393) greatly inhibited the infiltration of TAMs and the tumorigenicity of SACC cells. Conclusion: These new findings indicated that the CCL2/CCR2 axis promoted the progression of SACC cells via recruiting and reprogramming TAMs. Targeting TAMs by blocking the CCL2/CCR2 axis might be a prospective strategy for SACC therapy.