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991.
Receptor tyrosine kinase-like orphan receptor 2 (ROR2) is a tyrosine-protein kinase receptor highly implicated in the growth plate and cartilage development, which may be involved in epithelial-mesenchymal transition (EMT) in breast cancer (BC) cells. Although ROR2 is known to promote the migration of BC cells, the detailed mechanism of this event is still not clear. Here, we found that ROR2 expression was significantly increased in BC lymphatic metastatic tissue as well as BC samples compared to normal adjacent breast tissues. A higher expression of ROR2 in MDA-MB-231 and a lower expression of ROR2 in MCF-7 cells were observed. MDA-MB-231-siROR2 cells with ROR2 knockdown inhibited MDA-MB-231 cell invasion, migration, and clonal formation, while MCF-7-OvROR2 cells with overexpression showed the opposite results. The underlying mechanisms involved in ROR2-induced EMT in MDA-MB-231 and MCF-7 cells were further investigated. ROR2 may activate EMT progression in BC cells by altering MAPK kinase 3/6 (MKK3/6) expression. The expressions of transforming growth factor-β, matrix metalloproteinase-2 (MMP-2), and MMP-9, which were related to tumor cell invasion activities, were notably increased in MCF-7-OvROR2 cells. The EMT markers, including snail, N-cadherin, tissue inhibitor of metalloproteinases-1, and vimentin, were significantly upregulated in MCF-7-OvROR2 cells. On the contrary, E-cadherin was obviously reduced expressed in MCF-7-OvROR2 cells. ROR2 may regulate the malignant phenotype of BC cells possibly via activation of mitogen-activated protein kinase (MAPK)/p38 signaling pathway. Collectively, ROR2 promotes BC carcinogenesis by mediating the MAPK/p38 pathway, which is independent of Wnt5α.  相似文献   
992.
Ischemic heart disease (IHD) is a common cardiovascular disease, occurs when coronary artery blood circularity cannot match with the heart's need. The present work attempted to study the effects of long noncoding RNA (lncRNA) low expression in tumor (LET) on the progression of IHD. H9c2 cells were injured by hypoxia to mimic a cell model of IHD. The effects of lncRNA-LET on hypoxia-injured H9c2 cells were tested by using cell counting kit-8 assay, flow cytometry, and Western blot analysis. MicroRNA-138 (miR-138) expression was tested by a quantitative real-time polymerase chain reaction, and the expression of c-Jun N-terminal kinase (JNK) and p38MAPK (p38–mitogen-activated protein kinase) proteins was measured by Western blot analysis. We found that hypoxia exposure significantly repressed the viability of H9c2 cells, and induced apoptosis. Meanwhile, phosphorylation of JNK and p38MAPK was enhanced by hypoxia. The expression of lncRNA-LET was repressed by hypoxia. Overexpression of lncRNA-LET attenuated hypoxia-induced injury in H9c2 cells. Moreover, miR-138 was a downstream effector of lncRNA-LET, that miR-138 was highly expressed in lncRNA-LET-overexpressed cell. The cardioprotective effects of lncRNA-LET were abolished when miR-138 was silenced. In conclusion, this study revealed the cardioprotective function of lncRNA-LET. lncRNA-LET conferred its cardioprotective effects possibly via upregulation of miR-138 and thus repressing the JNK and p38MAPK pathways.  相似文献   
993.
This study aimed to identify differential circular RNA (circRNA) in the plasma exosomes of patients with lung adenocarcinoma (LUAD) using high-throughput sequencing. First, exosomes were isolated using an exosome isolation kit and confirmed by Western blotting, transmission electron microscopy, and NanoSight Assay. Subsequently, plasma circRNA expression profiles were screened by high-throughput sequencing and confirmed by fluorescence quantitative real-time polymerase chain reaction (qRT-PCR) and Sanger sequencing. Finally, the circRNA-miRNA-mRNA network was performed to forecast the potential function of circRNAs. The result of high-throughput sequencing data documented that 182 differentially expressed exosomal circRNAs in all were screened, which included 105 that were upregulated and 78 that were downregulated in LUAD patients plasma compared with controls. The four upregulated circRNAs including circ_0001492, circ_0001346, circ_0000690, and circ_0001439 were identical to the sequencing data by qRT-PCR, and their latent circRNA-miRNA-mRNA interactions were exhibited. Taken together, our study firstly revealed the altered exosomal circRNA expression from plasma samples in patients with LUAD and supports the need for exploring their potential as biomarkers and the pathological effects of lung cancer.  相似文献   
994.
Long noncoding RNAs (lncRNAs) play crucial roles in hepatocellular carcinoma (HCC). However, the underlying molecular mechanisms of small nucleolar RNA host gene 16 (SNHG16) for regulating the cell cycle and epithelial to mesenchymal transition (EMT) remain elusive. In this study, SNHG16 expression profiles of HCC tissues or cell lines were compared with those of normal tissues or hepatocyte cell line. The effect of SNHG16 knockdown in HCC cell lines was investigated by using in vitro loss-of-function experiments and in vivo nude mouse experiments. The potential molecular regulatory mechanism of SNHG16 in HCC progression was investigated by using mechanistic experiments and rescue assays. The results revealed that SNHG16 was highly expressed in HCC tissues and cell lines, which predicted poor prognosis of HCC patients. On one hand, the downregulation of SNHG16 induced G2/M cell cycle arrest, inducing cell apoptosis and suppression of cell proliferation. On the other hand, it inhibited cell metastasis and EMT progression demonstrated by in vitro loss-of-function cell experiments. Besides, knockdown of SNHG16 increased the sensitivity of HCC cells to cisplatin. For the detailed mechanism, SNHG16 was demonstrated to act as a let-7b-5p sponge in HCC. SNHG16 facilitated the G2/M cell cycle transition by directly acting on the let-7b-5p/CDC25B/CDK1 axis, and promoted cell metastasis and EMT progression by regulating the let-7b-5p/HMGA2 axis in HCC. In addition, the mechanism of SNHG16 for regulating HCC cell proliferation and metastasis was further confirmed in vivo by mouse experiments. Furthermore, these results can provide new insights into HCC treatment and its molecular pathogenesis, which may enlighten the further research of the molecular pathogenesis of HCC.  相似文献   
995.
996.
Aberrant expression of the tripartite motif containing 59 (TRIM59) has been reported to participate in the development and progression of various human cancers. However, its expression pattern and cellular roles in pancreatic cancer (PC) remains unclear. In our study, we found that TRIM59 expression was significantly increased in PC tissues and was positively correlated with several malignant behaviors and poor overall survival of PC patients based on bioinformatics analysis and immunohistochemistry staining. Functionally, small interfering RNA–mediated TRIM59 depletion inhibited cell proliferation and migration in vitro, while TRIM59 overexpression promoted cell proliferation and migration in vitro and drove tumor growth and liver metastasis in vivo. Mechanically, TRIM59 was found to enhance glycolysis through activating the PI3K/AKT/mTOR pathway, ultimately contributing to PC progression. Taken together, our results demonstrate that TRIM59 may be a potential predictor for PC and promotes PC progression via the PI3K/AKT/mTOR-glycolysis signaling pathway, which establishes the rationale for targeting the TRIM59-related pathways to treat PC.  相似文献   
997.
As a member of the low-density lipoprotein receptor (LDLR) superfamily, vitellogenin (Vg) receptor (VgR) is responsible for the uptake of Vg into developing oocytes and is a potential target for pest control. Here, a full-length VgR complementary DNA (named as CsVgR) was isolated and characterized in the rice stem borer, Chilo suppressalis. The composite CsVgR gene contained an open reading frame of 5,484 bp encoding a protein of 1,827 amino acid residues. Structural analysis revealed that CsVgR contained two ligand-binding domains (LBDs) with four Class A (LDLRA) repeats in LBD1 and seven in LBD2, which was structurally different from most non-Lepidopteran insect VgRs having five repeats in LBD1 and eight in LBD2. The developmental expression analysis showed that CsVgR messenger RNA expression was first detectable in 3-day-old pupae, sharply increased in newly emerged female adults, and reached a peak in 2-day-old female adults. Consistent with most other insects VgRs, CsVgR was exclusively expressed in the ovary. Notably, injection of dsCsVgR into late pupae resulted in fewer follicles in the ovarioles as well as reduced fecundity, suggesting a critical role of CsVgR in female reproduction. These results may contribute to the development of RNA interference-mediated disruption of reproduction as a control strategy of C. suppressalis.  相似文献   
998.
ABSTRACT

To evaluate the association between shift work and risk of type 2 diabetes mellitus, we searched PubMed, EMBASE and Web of Science from their inception to June 8, 2019. Observational studies examining the relationship between shift work and type 2 diabetes were included. Subgroup analyses were conducted to explore whether specific characteristics would affect the relationship. A dose-response relationship was estimated by using generalized least squares trend regression. Finally, twelve cohort studies and nine cross-sectional studies were included (inter-rater agreement, k = 0.96). The result of meta-analysis indicated that shift work was associated with an increased risk of type 2 diabetes (relative risk = 1.10, 95% confidence interval = 1.05–1.14). Subgroup analyses demonstrated that female shift workers have increased risk of type 2 diabetes while male not observed, health care workers showed the highest risk compared with civil servants and manual workers, and night shift and rotating shift were associated with an increased risk of type 2 diabetes. Dose-response meta-analysis based on three cohorts among female workers indicated that there might be a positive association between duration of shift work and the risk of type 2 diabetes. In conclusion, shift work is positively associated with an increased risk of type 2 diabetes. Among female workers, with the years of exposure to shift work prolonged, the risk of type 2 diabetes might increase accordingly. In the future, more studies are needed to confirm the results of dose-response analysis.  相似文献   
999.
Molecular Biology Reports - TBI is the main cause of death and disability in individuals aged 1–45 in Western countries. One of the main challenges of TBI at present is the lack of specific...  相似文献   
1000.
Gao  Pan  Gao  Jingjing  Dou  Xianming  Peng  Dangwei  Zhang  Yao  Li  Hu  Zhu  Tianle  Jiang  Hui  Zhang  Xiansheng 《Molecular biology reports》2020,47(5):3605-3613
Molecular Biology Reports - This study is to explore the relationship between vascular endothelial growth factor (VEGF) and pathological changes in cryptorchidism by using murine model of...  相似文献   
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