AIM: To explore the effect of pyrrolidine dithiocarbamate (PDTC), an NF-κB inhibitor, on the proliferation and apoptosis of human multiple myeloma U266 cells and its mechanisms.METHODS: The U266 cells were treated with PDTC at different concentrations (0, 25, 50, 100 and 200 μmol/L) in vitro.The growth inhibitory rate of the U266 cells was detected by CCK-8 assay and cell counting.The cell cycle of the U266 cells was determined by flow cyto-metry, and the apoptosis was examined by flow cytometry with Annexin V-FITC/PI staining.The effect of PDTC on the expression of DNA methyltransferase 1 (DNMT1) at mRNA and protein levels was measured by RT-qPCR and Western blot, respectively.The effects of PDTC on the protein levels of NF-κB (P65), DNMT1, Bcl-2, cyclin D1, cleaved caspase-3 and cleaved caspase-8 were determined by Western blot.RESULTS: The protein level of NF-κB (P65) was decreased after treatment with PDTC for 48 h or 72 h.PDTC inhibited the proliferation of U266 cells in both dose-and time-dependent manners.After treatment with PDTC for 48 h, the percentage of U266 cells in G2 phase increased compared with control group (P<0.05).PDTC induced the apoptosis of U266 cells in a dose-dependent manner.The expression of DNMT1 at mRNA and protein levels decreased (P<0.05).The results of Western blot showed that the expression of Bcl-2 in PDTC groups decreased, while the protein levels of cyclin D1, cleaved caspase-3 and cleaved caspase-8 were higher than those in control group (P<0.05).CONCLUSION: The NF-κB inhibitor PDTC inhibits the proliferation of U266 cells by inducing cell apoptosis.It may be related to the down-regulated expression of DNMT1, cell cycle arrest and activation of the apoptotic pathways.

In order to improve the operation difficulties in the narrow space of the nasal maxillary sinus, the nasal continuum minimally invasive surgical robot system is designed. The ball-and-socket joints and NiTiNol tubes are used as the main body of the continuum structure to improve the degree of freedom. The hardware systems and software systems are designed. The security control policies are planned. Finally, the robot confirmed prototype experiments are conducted and the feasibility of continuum robot confirmed through master-slave control experiment and animal experiment.
Animals ; Biomechanical Phenomena ; Equipment Design ; Minimally Invasive Surgical Procedures ; Robotic Surgical Procedures ; Robotics ; Software