ZNRF2 as an oncogene is transcriptionally regulated by CREB1 in breast cancer models.

E3 ubiquitin ligase Zinc and Ring Finger 2 (ZNRF2) has been demonstrated to be engaged in the development of multiple cancers. Nevertheless, the function of ZNRF2 in breast cancer (BC) still unclear. In this work, we firstly analyzed the differentially expressed genes in BC by bioinformatics and found that ZNRF2 was highly expressed in BC. Consistently, we further confirmed that ZNRF2 was upregulated in BC tissues compared with adjacent normal tissues, and this was positively correlated with the poor prognosis and the higher pathological grades of patients with BC. Functional assays performed on HCC1937 and MCF-7 cells indicated that silencing of ZNRF2 suppressed cell proliferation, as evidenced by the decrease in the expression of cyclin A, PCNA and cyclin D1. Flow cytometry and Hoechst staining showed that knockdown of ZNRF2 induced cell apoptosis, which was verified by the upregulation of apoptosis genes such as Bax, cleaved PARP and Bim. ZNRF2 knockdown also inhibited in vivo tumor growth. But, instead, ZNRF2-overexpressed BC cells exhibited obvious malignant phenotypes. Additionally, we observed that cAMP response element binding protein 1 (CREB1) directly bound to the promoter sequence of ZNRF2 and thus activating its transcription, suggesting that ZNRF2 is transcriptionally regulated by CREB1. Additionally, ZNRF2 knockdown could reverse the proliferation-promoting action of CREB1 on BC cells, Hence, this study demonstrated that ZNRF2 might serve as a prospective therapeutic target for BC.

[Smokeless tobacco extract affects biological properties of the pre-osteoblast cell line MC3T3-E1 ].

OBJECTIVE: To investigate the effects of smokeless tobacco extract (STE) on biological properties of osteoblast, and to identify possible pathological mechanisms of osseointegration. METHODS: MC3T3-E1 Sub-clone 14 cells were cultured in the presence of STE at 0 (control group),0. 01,0. 1,1,5,10 g/L. The cell proliferation was measured by MTT assay 1 d, 3 d, 5 d, and 7 d after exposure. The F-actin cytoskeleton of MC3T3 was stained with Rhodamine and DAPI, and then examined under a confocal laser scanning microscope 24 h after exposure to STE. The mRNA expressions of interleukin-6 (IL-6) and core-binding factor αl(Cbfαl) were quantified by real- time PCR (RT-qPCR) 48 h after exposure to STE. RESULTS: The MTT assay showed that 0. 01-10 g/L STE inhibited MC3T3 proliferation (P<0. 05). Prolonged time enabled 5-10 g/L STE to inhibit MC3T3 proliferation (P<0. 05). Network structure in F-actin cytoskeleton was demonstrated in the controls. In the cells exposed to STE, F-actin cytoskeleton started to change with disruptive structures. As the concentration of STE increased, the changes became more significant. STE increased the mRNA expression of IL-6 at the concentration of 5 g/L and 10 g/L (P<0.05), decreased the mRNA expression of Cbfα1 at the concentration of 0. 1-10 g/L (PO<0. 05). CONCLUSION: Tobacco may inhibit osteoblast proliferation, destroy F-actin cytoskeleton structure, increase the mRNA expression of IL-6 and decrease the mRNA expression of Cbfα1, and inhibit cell differentiation and adhesion accordingly. Smoking is a disadvantage to osseointegration.

[Effects of tobacco on rat gingival fibroblats attaching to titanium].

PURPOSE: The study was designed to observe the effects of the smokeless tobacco extract(ST) on the attachment,morphology,structure and proliferation of rat gingival fibroblasts(RGFs) to titanium in vitro. METHODS: RGFs were obtained from explants of rat normal gingival tissues by using tissue-explant technique.The origin of cells was identified by immunochemistry of vimentin and cytokeratin. RGFs to titanium were cultured in the presence of ST at various concentration,the attachment and growth of cells attached to titanium were measured by MTT method, immunofluorescence was used to detect and analyze the shapes of RGFs attached to titanium.Statistical analysis was performed using SPSS13.0 software package for one-way ANOVA. RESULTS: Immunochemical study showed that vimentin was expressed in RGFs while cytokeratin was negative,which indicated that RGFs were originated from mesoblastoma.With the increasing of ST concentration,the attachment,spreading shape and proliferation of RGFs in all groups decreased in a concentration-dependent manner.The difference between ST group and control group was statistically significant(P<0.05). CONCLUSIONS: ST can inhibit the attachment,spreading shape and proliferation of RGFs, suggesting that smoking may have influence on the long result of oral implant operation.

[Raman scattering studies on 0.5PZN-0.5PZT piezoceramics].

PZT based multi-system has shown super piezoelectric properties when the composition was located at morphotropic phase boundary (MPB), which divided the regions into rhombohedral and tetragonal structures equally. In the present paper, the diffuse phase transition and phase coexistence of rhombohedral and tetragonal phases of 0.5PZN-0.5PZT ceramics were investigated by Raman scattering spectroscopy in detail. The results revealed that compared with pure PZT, the width of Raman bands of 0.5PZN-0.5PZT was quite broad, indicating that the system has strong relaxor feature. According to the temperature dependence of dielectric permittivity, the indicator of degree of diffuseness, gamma, was calculated and the values were as high as 1.71. Through the separation by Gauss fitting of the Raman bands, the intensities of different Raman vibration modes, such as the tetragonal E (3TO), A1 (3TO), E (4LO) and A1 (3LO) modes, as well as the rhombohedral R1 and Rh modes, were determined. The results indicated that for 0.5PZN-0.5PZT system, the fraction of rhombohedral phase was equal to the tetragonal phase, which has also been affirmed by XRD results and suggested that the system was close to the MPB. Excellentpiezoelectric properties, such as kp (0.66) and d33 (425 pC/N), were found in 0.5PZN-0.5PZT system, showing a great promise of this system as practical materials for piezoelectric actuators.