EZH2 regulates the malignancy of human glioblastoma cells via modulation of Twist mRNA stability.

Glioblastoma multiforme (GBM) is a lethal primary brain tumor with poor survival lifespan and dismal outcome. However, the effects and mechanisms of epigenetic factors on the development of GBM were still not well illustrated. We found that expression of enhancer of zeste homolog 2 (EZH2), which can catalyze histone H3K27me3 to modulate gene expression, was increased in GBM cells. Knockdown of EZH2 can suppress proliferation and migration, while increase temozolomide (TMZ) sensitivity, of GBM cells. Further, knockdown of EZH2 or its specific inhibitor GSK126 can decrease expression of Twist, while over expression of Twist can reverse si-EZH2-suppressed malignancy of GBM cells. Mechanistically, EZH2 can positively regulate mRNA stability of Twist1 mRNA. Further, miR-206, which can bind with 3'UTR of Twist1 mRNA, was involved in EZH2-regulated mRNA stability of Twist1. Collectively, our data suggest that EZH2 might be a potential target for GBM treatment. Further, miR-206/Twist axis is involved in EZH2-regulated malignancy of GBM cells.

Anatomical mechanism of spontaneous recovery in regions caudal to thoracic spinal cord injury lesions in rats.

BACKGROUND: The nerve fibre circuits around a lesion play a major role in the spontaneous recovery process after spinal cord hemisection in rats. The aim of the present study was to answer the following question: in the re-control process, do all spinal cord nerves below the lesion site participate, or do the spinal cord nerves of only one vertebral segment have a role in repair? METHODS: First we made a T7 spinal cord hemisection in 50 rats. Eight weeks later, they were divided into three groups based on distinct second operations at T7: ipsilateral hemisection operation, contralateral hemisection, or transection. We then tested recovery of hindlimbs for another eight weeks. The first step was to confirm the lesion had role or not in the spontaneous recovery process. Secondly, we performed T7 spinal cord hemisections in 125 rats. Eight weeks later, we performed a second single hemisection on the ipsilateral side at T8-T12 and then tested hindlimb recovery for another six weeks. RESULTS: In the first part, the Basso, Beattie, Bresnahan (BBB) scores and the electrophysiology tests of both hindlimbs weren't significantly different after the second hemisection of the ipsilateral side. In the second part, the closer the second hemisection was to T12, the more substantial the resulting impairment in BBB score tests and prolonged latency periods. CONCLUSIONS: The nerve regeneration from the lesion area after hemisection has no effect on spontaneous recovery of the spinal cord. Repair is carried out by all vertebrae caudal and ipsilateral to the lesion, with T12 being most important.

[Effects of inter-row economic crop planting on soil moisture in a rain-fed jujube orchard in loess hilly region, China].

Soil moisture variation in dryland sloping jujube. orchard was investigated after introducing two economic crops, i.e., feed Brassica napus (JR) and Hemerocallis fulva (JH) planted between jujube rows. Jujube tree without inter-row crop was set as control (CK). The results showed that mean soil moisture for JR and JH in the 0-180 cm soil layer increased by 6.2% and 10.1% compared with CK, respectively. Soil moisture changed mainly in the 0-60 cm soil layer in growth stage of Jujube trees. Soil moisture in JR and JH treatments significantly increased in the 0-60 cm soil layer, which could meet the demand in water resource of jujube plantation. The water consumption of jujube trees also mainly concentrated in the 0-60 cm soil layer. There was a significant decay exponential relationship between the soil moisture in the 0-20 cm layer and the drought duration after rainfall. During the 18-day dry period after rain, the soil moisture contents of JR and JH were apparently higher than that of CK. In conclusion, the jujube-crop intercropping system improved the soil moisture condition. It was an effective measure to overcome the seasonal drought in jujube orchards on the loess hilly region.

The cyclophosphamide metabolite, acrolein, induces cytoskeletal changes and oxidative stress in Sertoli cells.

The aim of this study is to explore the mechanism by which acrolein (ACR), a metabolite of cyclophosphamide (CP), induces immature Sertoli cell cytoskeletal changes. Sertoli cells obtained from rats were cultivated and treated with 50 and 100 µM ACR. XTT assays were performed to detect cell viability. Activities of superoxide dismutase (SOD), glutathione peroxidases (GSH-Px), and catalase (CAT), as well as total anti-oxidation competence (T-AOC) were examined. Superoxide anion levels were detected by a fluorescent probe. Cell ultrastructure changes were observed by transmission fluorescent microscope. Actin filament (F-actin) distribution was detected by immunofluorescence, and ERK and p38MAPK expression were detected by western blot analysis. ACR significantly decreased the viability of Sertoli cells in a dose- and time-dependent manner. T-AOC and the antioxidant activity of SOD, CAT and GSH-Px, were decreased in ACR-treated groups compared with the control group. The levels of reactive oxygen species (ROS) in ACR-treated Sertoli cells were increased. In addition, characteristics of cell apoptosis such as mitochondrial swelling, aggregated chromatin, condensed cytoplasm, nuclei splitting, and nuclei vacuolization were observed in ACR-treated cells. Furthermore, ACR-treatment also induced microfilament aggregation, marginalization and regionalization. The expression levels of ERK and p38MAPK were also increased in ACR-treated cells in a dose- and time-dependent manner. ACR, a major CP metabolite, impairs the cytoskeleton which is likely caused by induction of the oxidative stress response through up-regulation of ERK and p38MAPK expression.