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The polymerization of isoprene was examined by using a novel binary catalyst system composed of neodymium chloride tributylphosphate (NdCl 3 Á3TBP) and methylaluminoxane (MAO). The NdCl 3 Á3TBP/MAO catalyst worked effectively in a low MAO level ([Al]/[Nd] 5 50) to afford polymers with high molecular weight (M n $10 5 ), narrow molecular weight distribution (M w / M n 5 1.4-1.6), and high cis-1,4 stereoregularity (> 96%). The catalytic activity increased with an increasing [Al]/[Nd] ratio from 30 to 100 and polymerization temperature from 0 to 50 C, while the M n of polymer decreased. The presence of free TBP resulted in low polymer yield. Polymerization solvent remarkably affected the polymerization behaviors; the polymerizations in aliphatic solvents (cyclohexane and hexane) gave polymer in higher yield than that in toluene. The M w /M n ratio of the producing polymer remained around 1.5 and the gel permeation chromatographic curve was always unimodal, indicating the presence of a single active site in the polymerization system.

Although there are numerous treatment strategies, including surgery and chemotherapy, the prognosis of cervical cancer remains far from satisfactory. There is an urgent need to develop more effective, more tolerable and safer therapeutics for the treatment of cervical cancer. Lycorine is a natural plantextract that has been previously found to confer anti-tumor activities. Therefore, in the present study, the effects of lycorine and its possible mechanism of action in cervical cancer were investigated. Cell Counting Kit-8, wound healing and Transwell assays were used to verify the proliferation and migration of HeLa cells following lycorine intervention. The results demonstrated that lycorine significantly inhibited the proliferation and migration of HeLa cells. RNA binding motif 10 (RBM10) is a protein associated with apoptosis. It has been suggested that lycorine can affect the expression of RBM10. Flow cytometry demonstrated that lycorine may inhibit the initiation and progression of cervical cancer by promoting apoptosis, which may be mediated through the upregulation of RBM10 expression and increasing TNF-α levels. Xenograft mouse experiments indicated that when lycorine was injected through the tail vein, HeLa tumor growth was inhibited. Mechanistically, western blotting demonstrated that lycorine significantly inhibited the activation of the Akt signaling pathway and potentially reversed epithelial-mesenchymal transition, which was also mediated by RBM10. Furthermore, following RBM10 knockdown with small interfering-RNA, the inhibitory effects of lycorine on cervical cancer was significantly abrogated. Overall, results of the present study suggest that lycorine can upregulate the expression of RBM10 and inhibit the proliferation and migration of cervical cancer cells.

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