Background CRNDE is known to be an important predictive factor of prognosis in many tumors; however, its role in cisplatin resistance is still unknown in ovarian cancer. The aim of the current research was to investigate the association between CRNDE and cisplatin resistance. Materials and methods QRT-PCR and in situ hybridization assay were employed to detect the expression of CRNDE in ovarian cancer cells and tissues; CCK8 assay, AnnexinV-FITC apoptosis assay and Trans-well assay, to determine the cell proliferation , apoptosis and invasion; and RNA-pull down assay, mass spectrometry analysis, gene microarray to search the targeted gene of CRNDE and SRSF1 . Association of CRNDE with SRSF1 was determined in ovarian cancer cells and nude mice . Results It was found that CRNDE and SRSF1 expression were higher in the cisplatin resistant ovarian cancer cells than their control cells. High expression of CRNDE and SRSF1 led to cisplatin resistance. While inhibition of CRNDE or SRSF1 sensitized ovarian cancer to cisplatin in vitro and in vivo. Moreover, as indicated in RIP assay, SRSF1 was potentially the targeted gene of CRNDE, and CRNDE promoting SRSF1 expression to induce cisplatin resistance; as indicated in gene microassay, there was significantly positive correlation between SRSF1 and TIA1 , and SRSF1 promoting TIA1 expression. Conclusion In conclusion, CRNDE induced cisplatin resistance in ovarian cancer through SRSF1/TIA1 signaling pathway ; thus, CRNDE inhibitor or SRSF1 inhibitor combined with cisplatin might act as a novel promising approach to ovarian cancer.
Jun Li,Ji-Zhi Xu,Bo Dou,Teng-Fei Huang,Jie Chen,Tuan-Mei Wang,Hong-Juan Ouyang
The epithelial–mesenchymal transition (EMT) is closely associated with Crohn's disease (CD) related intestinal fibrosis, a condition whose prevalence is increasing annually among children. Recently, the CD marker gene microarray screening revealed an upregulation of circ_0001666 in the colon tissues of CD patients, but its underlying mechanisms remain unclear. In this study, we explored the molecular mechanism of circ_0001666 in regulating EMT-mediated fibrosis in CD in vitro. The levels of circ_0001666 and EMT-associated proteins were assessed in CD clinical samples, and a CD cell model was established using TGF-β1 to induce human intestinal epithelial cells (HIECs). Additionally, the expression levels of genes and proteins related to EMT and fibrosis were analyzed by quantitative real-time PCR and western blot, cell migration, and invasion were assessed via wound healing assay and transwell, respectively, and RNA pull-down and RNA immunoprecipitation assays were performed to verify the relationship between SRSF1 and BMP7 or circ_0001666. Circ_0001666 was overexpressed in the intestinal mucosal tissues of CD patients and was positively correlated with EMT. Silencing circ_0001666 inhibited the migration, invasion, EMT, and fibrosis of HIECs induced by TGF-β1. Mechanistically, circ_0001666 regulated BMP7 expression by interacting with SRSF1. Furthermore, the effects of inhibiting circ_0001666 on HIECs could be partially reversed by overexpressing SRSF1 or silencing BMP7. Collectively, circ_0001666 regulates TGF-β1-induced HIEC migration, invasion, EMT, and fibrosis. Circ_0001666 also promoted EMT-mediated fibrosis by interacting with SRSF1 to accelerate BMP7 mRNA decay. These findings provide new insights into the pathogenesis of CD and suggest that circ_0001666 might be a potential therapeutic target for CD.