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The pathogenesis and cisplatin chemoresistance of ovarian cancer (OC) are still unclear. Vacuolar protein sorting‐associated 33B (VPS33B) has not been reported in OC to date. In this study, immunohistochemistry was used to detect VPS33B protein expression between OC and ovarian tissues. MTT, EdU, colony formation, cell cycle, in vivo tumorigenesis, western blot, ChIP, EMSA, co‐immunoprecipitation (CoIP), qRT‐PCR, and microconfocal microscopy were used to explore the function and molecular mechanisms of VPS33B in OC cells. The results of the present study demonstrated that VPS33B protein expression was obviously reduced in OC compared with that in ovarian tissues. Overexpressed VPS33B suppressed cell cycle transition, cell growth, and chemoresistance to cisplatin in vitro and in vivo. Analysis of the mechanism indicated that overexpressed VPS33B regulated the epidermal growth factor receptor (EGFR)/PI3K/AKT/c‐Myc/p53/miR‐133a‐3p feedback loop and reduced the expression of the cell cycle factor CDK4. Nasopharyngeal epithelium‐specific protein 1 (NESG1) as a tumor suppressor not only interacted with VPS33B, but was also induced by VPS33B by the attenuation of PI3K/AKT/c‐Jun‐mediated transcription inhibition. Overexpressed NESG1 further suppressed cell growth by mediating VPS33B‐modulated signals in VPS33B‐overexpressing OC cells. Finally, NESG1 induced VPS33B expression by reducing the inhibition of PI3K/AKT/c‐Jun‐mediated transcription. Our study is the first to demonstrate that VPS33B serves as a tumor suppressor, and VPS33B can interact with NESG1 to suppress cell growth and promote cisplatin sensitivity by regulating the EGFR/PI3K/AKT/c‐Myc/p53/miR‐133a‐3p feedback loop in OC cells., VPS33B can interacts with NESG1 to suppress cell growth and promote cisplatin sensitivity by regulating the EGFR/PI3K/AKT/c‐Myc/p53/miR‐133a‐3p feedback loop in OC cells.

Chemical vapor deposition (CVD) diamond film has high heat resistance, high thermal stability, and other excellent properties as nature single-crystalline diamond. The surface polishing, large size planarization, and high material removal rate of CVD diamond film are limited due to its special crystal structure and excellent physicochemical characteristics. Dynamic friction polishing (DFP) technology is a new and effective polishing method of diamond. In this paper, according to the theory of graphitization of diamond catalyzed by unpaired d electrons, two manganese-based alloys, Mn–Cu and Mn–Ni, are selected as polishing materials to achieve high quality and high efficiency polishing of diamond and verify the mechanism of DFP. Alloying polishing plates were prepared by mechanical alloying method and spark plasma sintering technology. The polishing results of Mn–Cu and Mn–Ni alloys were compared and analyzed through DFP experiments. The experimental results showed that since Mn–Ni alloy has more unpaired ...

Dynamic friction polishing (DFP) chemical vapor deposition diamond film with high quality and efficiency puts forward a high demand for the polishing plate. Based on the catalysis of metal material on diamond and requirements of DFP technique, three alloy polishing plates are prepared by mechanical alloying method combined with spark plasma sintering technology. The performance of polishing plates is explored through experiments. Phases and microstructures of polishing plates are analyzed using X-ray diffraction (XRD), scanning electron microscope (SEM), and Raman spectroscope. The results demonstrate that, among all materials experimented, the tungsten-based alloy shows the most excellent polishing performance. The removal rate of diamond film is up to 1.5µm/min, but the wear rate of polishing plate is only 0.35 mm3/min. Graphitization of diamond removal mechanism is discussed by detecting and analyzing the experimental results. Also, the feasibility of DFP technique is verified in field of catalytic mac...