Circ_0091581 Promotes the Progression of Hepatocellular Carcinoma Through Targeting miR-591/FOSL2 Axis
DIGESTIVE DISEASES AND SCIENCES
Authors: Ji, Chenggang; Hong, Xiaocheng; Lan, Bo; Lin, Ye; He, Yingxin; Chen, Jiayang; Liu, Xi; Ye, Weijie; Mo, Zhikang; She, Zhanpeng; Lin, Shuwen
Abstract
Background Circular RNAs (circRNAs) have shown crucial regulatory roles in cancer biology. We aimed to uncover the role and underlying mechanism of circ_0091581 in hepatocellular carcinoma (HCC) progression. Methods The abundance of circ_0091581, microRNA-591 (miR-591) and FOS like 2, AP-1 transcription factor subunit (FOSL2) was measured by quantitative real-time polymerase chain reaction. Cell viability, colony formation ability, and invasion ability were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony formation assay, and transwell invasion assay. The migration ability was analyzed by transwell migration assay and wound healing assay. Flow cytometry was used to evaluate the cell cycle and apoptosis of HCC cells. The interaction between miR-591 and circ_0091581 or FOSL2 was predicted by Circular RNA Interactome database or TargetScan database and confirmed by dual-luciferase reporter assay and RNA immune co-precipitation assay. FOSL2 protein expression was measured by Western blot assay. Xenograft tumor assay was conducted to analyze the role of circ_0091581 in HCC tumor growth in vivo. Results Circ_0091581 was highly expressed in HCC tissue samples and cell lines in contrast to that in adjacent normal tissue samples and THLE-2 cell line. Circ_0091581 accelerated the viability, colony formation, metastasis, and cell cycle, while it impeded the apoptosis of HCC cells. MiR-591 bound to circ_0091581, and circ_0091581 knockdown-mediated effects in HCC cells were largely overturned by miR-591 silencing. FOSL2 was a target of miR-591, and FOSL2 overexpression largely reversed miR-591 accumulation-induced influences in HCC cells. FOSL2 protein expression was down-regulated by circ_0091581 silencing, and the addition of miR-591 inhibitor partly recovered the expression of FOSL2 in HCC cells. Circ_0091581 interference notably suppressed HCC tumor growth in vivo. Conclusion Circ_0091581 acted as an oncogene to enhance the viability, colony formation, metastasis and cell cycle and inhibit the apoptosis of HCC cells through targeting miR-591/FOSL2 axis.
Regulation of Cued Fear ExpressionviaCorticotropin-Releasing-Factor Neurons in the Ventral Anteromedial Thalamic Nucleus
NEUROSCIENCE BULLETIN
Authors: Lv, Yin; Chen, Peng; Shan, Qing-Hong; Qin, Xin-Ya; Qi, Xiu-Hong; Zhou, Jiang-Ning
Abstract
The ventral part of the anteromedial thalamic nucleus (AMv) is in a position to convey information to the cortico-hippocampal-amygdalar circuit involved in the processing of fear memory. Corticotropin-releasing-factor (CRF) neurons are closely associated with the regulation of stress and fear. However, few studies have focused on the role of thalamic CRF neurons in fear memory. In the present study, using a conditioned fear paradigm in CRF transgenic mice, we found that the c-Fos protein in the AMv CRF neurons was significantly increased after cued fear expression. Chemogenetic activation of AMv CRF neurons enhanced cued fear expression, whereas inhibition had the opposite effect on the cued fear response. Moreover, chemogenetic manipulation of AMv CRF neurons did not affect fear acquisition or contextual fear expression. In addition, anterograde tracing of projections revealed that AMv CRF neurons project to wide areas of the cerebral cortex and the limbic system. These results uncover a critical role of AMv CRF neurons in the regulation of conditioned fear memory.