The Effect of Simvastatin on mRNA Expression of Transforming Growth Factor-β1,Bone Morphogenetic Protein-2 and Vascular Endothelial Growth Factor in Tooth Extraction Socket

Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 （TGF-β1）, bone morphogenetic protein-2 （BMP-2） and vascular endothelial growth factor （VEGF） in the tooth sockets of rat. Methodology Forty-eight male Wistar rats were randomly divided into experimental and control groups （n=24）. Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-β1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation. Results The fusiform stroma cells in the tooth extraction socket began to express TGF-β1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-131 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group. Conclusion The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket.

Regulation of autophagy on epithelial mesenchymal transformation in oral squamous cell carcinoma

Objective: To investigate the role and mechanism of autophagy in epithelial-mesenchymal transition (EMT) of oral squamous cell carcinoma cells induced by CQ (chloroquine) and rapamycin (RAPA). Methods: TGF-β (transforming growth factor β) was used to induce EMT in Cal-27 cell line. At the same time, RAPA was used to enhance and CQ was used to inhibit autophagy. The ability of cell migration was detected by scratch distribution test and the ability of cell migration was detected by Transwell chamber test. Western blot was used to detect the changes of ZO-1, vimentin, FN1 and other EMT-related proteins after 3 d induction, and SPSS 22.0 statistical software was used to analyze the data. Results: After 3 d of induction with 5 ng/mL TGF-β, E-cadherin decreased significantly and Vimentin increased significantly. Compared with the control group, the wound healing rate increased significantly (P<0.05) and the number of penetrating cells increased significantly (P<0.05) after 3 d induction with 5 ng/mL TGF-β, and then the cells were co-induced with 100 ng/mL RAPA and 100 ng/mL CQ and 5 ng/mL TGF-β for 3 d. Compared with TGF-β group. The healing rate of the RAPA co-induced with 5 ng/mL TGF-β group decreased significantly (P<0.05) and the number of penetrating cells decreased significantly (P<0.05). Compared with TGF-β group. The healing rate of the CQ co-induced with 5 ng/mL TGF-β group increased significantly (P<0.05) and the number of penetrating cells increased significantly (P<0.05). Compared with the control group, FN1 and Vimentin expression increased and ZO-1 expression decreased 3 d after induction with 5 ng/mL TGF-β. And then induced Cal-27 cells with 100 ng/mL RAPA and 100 ng/mL CQ and 5 ng/mL TGF-β respectively for 3 d. Compared with TGF-β group, FN1 and Vimentin expression decreased in RAPA co-induction group. Compared with TGF-βgroup, the expression of FN1 and Vimentin increased and the expression of ZO-1 decreased in CQ co-induction group. Conclusion: TGF-β can induce Cal-27 cells to establish EMT model. In EMT model, promoting autophagy can inhibit EMT, inhibiting autophagy can promote EMT.

Advances in the study of the effect of tumor stromal cells on oral cancer

Oral squamous cell carcinoma (OSCC) is the most common malignant tumour in oral and maxillofacial region. The interaction between stromal cells and tumor cells is involved in the proliferation, differentiation, apoptosis, adhesion and migration of tumor cells, and is closely related to the malignant degree and prognosis of tumors. The development of OSCC is of great significance to the treatment of OSCC. This paper summarizes the sources of several important stromal cells and their effects on tumor cells, which provides a theoretical basis for the treatment of OSCC.

Antibacterial property of a gradient Cu-bearing titanium alloy by laser additive manufacturing

Streptococcus mutans(S.mutans)is the most common cariogenic bacteria and causes caries by forming biofilms.A novel gradient Cu-bearing titanium alloy(TC4-5Cu/TC4)was manufactured using selective laser melting(SLM)technology for dental applications,which is anticipated to inhibit the formation of biofilm.In this study,the released concentration of copper ions in both minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)was tested in order to assess the antibacterial property of the alloy against planktonic S.mutans,and the antibacterial and antibiofilm efficiencies of TC4-5Cu/TC4 alloy against sessile S.mutans were evaluated via quantitative antibacterial tests and biofilm determination.Reverse transcription polymerase chain reaction(RT-PCR)was performed to analyze the expression of biofilm-related genes(gtfB,gtfC,gtfD,ftf and gbpB)and acid production-related gene(ldh).The results suggested that the MIC and MBC of Cu^(2+)were much higher than the release concentration of copper ions of the alloy,which was consistent with the lack of antibacterial effect against planktonic bacteria.On the contrary,TC4-5Cu/TC4 alloy exhibited significant bactericidal property against the sessile bacteria and efficient biofilm-restrained ability,and all genes detected in this research were down-regulated.The results indicated that the TC4-5Cu/TC4 alloy suppressed biofilm formation and the sessile bacterial viability by down-regulating biofilm-related genes.