Реферат
Neural tube defects (NTDs) are congenital defect diseases caused by cell proliferation and apoptosis disorders. Using RNA-Seq assays, we found the increased expression of DNA damage-inducible transcript 4 (Ddit4) in embryonic brain tissues from NTD fetuses. In this study, we intend to explore the effects of Ddit4 overexpression on the proliferation and apoptosis of HT-22 cells and related mechanisms to lay the foundation for the study of the role of Ddit4 in NTDs. According to the mouse Ddit4 sequence, we constructed the eukaryotic expression vector pEX-3-Ddit4. The results of restriction enzyme analysis and sequencing showed that the eukaryotic expression vector pEX-3-Ddit4 was successfully constructed. qRT-PCR and Western blotting results showed that the expression level of Ddit4 in HT-22 cells was significantly increased after transfection of PEX-3-Ddit4 (P < 0. 01) . CCK-8 and Western blotting results showed that Ddit4 overexpression decreased the proliferation of HT-22 cells (P < 0. 01) . Flow cytometry showed that Ddit4 overexpression increased the proportion of cells in the G
Реферат
Background and purpose:MicroRNA (miRNA, miR) plays an important regulatory role in cancer. miR-222 is reported to be up-regulated in various tumors, but its role in renal cell carcinoma (RCC) remains unclear. In this study, we detected the expression of miR-222 in both RCC and adjacent tissue samples. The aim of this study was to investigate the role of miR-222 in RCC. Methods:The expression levels of miR-222 in RCC tissue samples were quantified by quantitative real-time polymerase chain reaction (qRT-PCR). DDIT4 and LC3-Ⅱ protein expressions were determined by Western blot. Dual luciferase assay was performed to verify the target of miR-222. EGFP-LC3 microscopy assay was performed to assess autophagy. Results:Results from qRT-PCR showed that the expression of miR-222 was up-regulated in RCC tissues. Knockdown of miR-222 with speciifc antagomiR decreased the cell viability of 786-O cells, whereas overexpression of miR-222 increased the cell viability (P<0.01). The levels of DDIT4 were up-regulated in 786-O cells transfected with miR-222 antagomiR, whereas overexpression of miR-222 induced the down-regulation of DDIT4 expression. Data from dual luciferase assay indicated that miR-222 directly targeted the expression of DDIT4. Consistently, the expression of DDIT4 in RCC tissues was down-regulated compared with adjacent tissues. Knockdown of miR-222 in 786-O cells induced a signiifcant increase of autophagosome formation and LC3 lipidation.These results supported that miR-222 could inhibit autophagy in RCC cells, which may affect the clinical characteristcs of RCC. Conclusion: miR-222 is up-regulated in RCC and can inhibit the autophagy of RCC cells through down-regulating the expression of DDIT4.