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Background: Dickkopf-4 (DKK4), a member of DKK family, appears to be a divergent protein. It remained multi-biological functions in carcinogenesis. The effect of DKK4 on the ovarian cancer cells remains unclear. This study detected the clinical significance of DKK4 in epithelial ovarian cancer (EOC) patients and its role in invasion.Methods: QRT-PCR and western blot analysis were used to examine the levels of DKK4 mRNA and protein in 33 EOC tissues and 33 benign ovarian tumors. Immunohistochemical analysis was performed to assess DKK4 expression in 239 EOC samples. siRNA-mediated DKK4 silence was conducted. Transwell assay was used to detect the invasive ability. Phalloidin was used to stain the formations of actin filaments.Results: The expressions of DKK4 mRNA and protein were elevated in EOC tissues as compared with those in benign ovarian tumors (p = 0.001 and <0.0001 respectively). Immunohistochemical results showed the strong expression of DKK4 protein was positively associated with late FIGO stage (p = 0.005) and poor disease free survival in univariate and multivariate analysis (p < 0.0001 and p = 0.001, respectively). SiRNA-mediated DKK4 knockdown inhibited cell invasive ability (all p < 0.0001) and the formations of actin filaments. DKK4 could promote the phosphration of c-JUN and JNK (p < 0.0001 and p = 0.001, respectively).Conclusions: Our results indicated that DKK4 might be contributed to predicting EOC progression and prognosis. DKK4 could promote the invasion of EOC through JNK activation. [ABSTRACT FROM AUTHOR]

In this study, the impact of codoping Mg and Ti on the thermoelectric performance of AgSbTe 2 materials was investigated. Through a two-step synthesis process involving slow cooling and spark plasma sintering, AgSb 0.98- x Mg 0.02 Ti x Te 2 samples were prepared. The introduction of Mg and Ti dopants effectively suppressed the formation of the undesirable Ag 2 Te phase. Density functional theory (DFT) calculations confirmed that Ti doping facilitated the band convergence, leading to a reduction in the effective mass of the carriers. This optimization enhanced carrier mobility and, consequently, electrical conductivity. Additionally, the codoping strategy resulted in the reinforcement of point defects, which contributed to a decrease in lattice thermal conductivity. The AgSb 0.98- x Mg 0.02 Ti x Te 2 sample achieved a maximum figure of merit (ZT) value of 1.45 at 523 K, representing an 87% improvement over the undoped AgSbTe 2 sample. The average ZT value over the temperature range of 323-573 K was 1.09, marking a significant enhancement in thermoelectric performance. This research demonstrates the potential of Mg and Ti codoping as a strategy to improve the thermoelectric properties of AgSbTe 2 -based materials.

In this study, we employ first-principles calculations to explore the electronic and valleytronic properties of single-layer (SL) SMSiN 2 (M = Mo, W), which are two-dimensional Janus materials with strong spin-orbit coupling. Our findings indicate that SL SMoSiN 2 /SWSiN 2 possess a direct/indirect band gap, where the valence band maximum is situated at the K / K ' point, giving rise to the formation of degenerate valleys. When considering spin-orbit coupling, SMoSiN 2 and SWSiN 2 demonstrate intriguing valley spin splitting in their valleys, with a maximum splitting of up to 0.14/0.39 eV in the valence bands. By implementing magnetic doping with V and Cr, we provide a demonstration that valley polarization could be realized in SL SMSiN 2 . Moreover, the findings reveal high carrier mobility in SL SMSiN 2 , notably in SWSiN 2 , where hole carriers can achieve a remarkable mobility of up to 7.98 × 10 3 cm 2 V -1 s -1 along the zigzag direction. Furthermore, our observations suggest that strain can be effectively utilized to manipulate the character and magnitude of the band gap, as well as the valley spin splitting in these materials.