Repair of spinal cord injury by chitosan scaffold with glioma ECM and SB216763 implantation in adult rats.

The loss of spinal cord tissue and the cavity formation are major obstacles to the repair of spinal cord injury (SCI). In the study, the scaffold of chitosan+ECM+SB216763 was fabricated and used for the repair of injured spinal cord injury. First, the biocompatibility of the scaffold was analyzed and results showed that the scaffold had a good compatibility with the neural stem cells. Especially, the processes of differentiated neural stem cell embedded in the scaffold were found in the experiment. At the same time, we also investigated the effect of scaffold on the differentiation of neural stem cell. The results showed that the scaffold of chitosan+ECM+SB216763 could significantly promote the differentiation of neural stem cells into neurons, astrocytes, and oligodendrocytes relative to those in other groups. In order to probe the application of scaffold in vivo, the rat models of spinal cord hemisection were set up and scaffolds were implanted into transected gap. Then the electrophysiology and BBB score were evaluated and results showed that the amplitude, latency period and BBB score in chitosan+ECM+SB216763 group were dramatically better than those in other groups. In addition, the differentiation of neural stem cells into nerve cells was also assayed and the results revealed that the number of neural stem cells differentiating into neuron, astrocytes and oligodendrocytes in chitosan+ECM+SB216763 group was significantly bigger than those in other groups. All these data suggested that the scaffold of chitosan+ECM+SB216763 would be a promising medium for the repair of injured spinal cord.

Promoter methylation assay of SASH1 gene in breast cancer.

PURPOSE: To analyze the relationship between the expression of SASH1 and its methylation level of SASH1 gene promoter in human breast cancer. METHODS: Expression levels of SASH1 were examined in breast cancer tissues and adjacent normal tissues with immunohistochemistry and with real time PCR (RT-PCR) methylation analysis was performed with MassArray. RESULTS: Immunohistochemistry showed that SASH1 expression was strongly reduced in breast cancer compared with adjacent normal tissues. Quantitative methylation analysis by MassArray revealed that CpG sites in SASH1 promoter shared similar methylation pattern in tumor tissue and adjacent normal tissue. The CpG sites with significant difference in methylation level were CpG_26.27 and CpG_54.55. Moreover, 5-aza-2'-deoxycytidine (5-Aza-dc) treatment of tumor cell line MDA-MB-231 caused significant elevation of SASH1 mRNA. CONCLUSION: Based on these data, we propose that increase of DNA methylation level in the promoter region of gene SASH1, particularly CpG_26.27 or CpG_54.55 sites, possibly repressed SASH1 expression in breast cancer.