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Journal of Plant Growth Regulation - The brassinosteroids (BRs) constitute a recently defined class of plant hormone that can enhance the resistance of plants to multiple stresses. However, the...  相似文献   
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Glioma is one of the most common primary malignancies of the central nervous system, which has aggressive clinical behavior and a poorer prognosis. MicroRNAs (miRs) are a class of small noncoding RNAs that function as mediators of gene expression, which can be sponged by circRNA provided with a closed circular structure. Dysregulations of circular RNAs (circRNAs) and miRs have been implicated in the development and progression of glioma. In the current study, we investigated the role of circular RNA hsa_circ_0076248 in mediating the oncogenesis of glioma by sponging miR-181a to modulate silent information regulator 1 (SIRT1) expression in vitro and in vivo. The quantitative real-time polymerase chain reaction results showed that the expression of miR-181a was significantly decreased in glioma tissues and cell lines compared with normal brain tissues and normal gliocyte, respectively, and the expression of hsa_circ_0076248 and SIRT1 demonstrated the opposite. Bioinformatics analysis identified hsa_circ_0076248 could sponge miR-181a, and miR-181a could target the mRNA of SIRT1. Our results verified that downregulating hsa_circ_0076248 or upregulating miR-181a could depress the proliferation and invasion of glioma in vitro and in vivo. The experiment also showed that downregulating hsa_circ_0076248 or upregulating miR-181a could remarkably promote the temozolomide chemotherapy sensitivity. Furthermore, Western blot analysis testified that downregulating hsa_circ_0076248 or upregulating miR-181a could promote the expression of p53 and SIRT1. In summary, our study sheds light on the regulatory mechanism of hsa_circ_0076248 in glioma growth and invasion via sponging miR-181a, which downregulates the SIRT1 expression and also suggests that hsa_circ_0076248, miR-181a, and SIRT1 may serve as potential therapeutic targets for glioma.  相似文献   
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Postoperative hepatocellular carcinoma (HCC) recurrence and metastasis throw great threaten to its overall survival (OS). This paper focus on exploring the prognostic significance of NANOG and OCT4 expression in HCC recurrence and OS after liver transplantation. Eighty-six patients who meet University of California San Francisco (UCSF) criteria and underwent liver transplantation in Tianjin First Central Hospital between August 2010 and August 2013 were included. Expression of NANOG and OCT4 was determined by immunohistochemistry. The relationships between NANOG and OCT4 expression with tumor recurrence, tumor count, histology stage, lymph node metastasis (LNM) and microvascular invasion (MVI) were explored through the χ2 test and Cox regression analysis. We found that 19/26 and 20/24 patients with positive expression of NANOG and OCT4 relapsed. Combination of NANOG and OCT4 expression was indicated as valuable prognostic signature for HCC recurrence prediction (P < 0.0011). Besides, we identified other key factors with significant correlations with recurrence, such as LNM (P = 0.011) and MVI (P = 0.024). Strikingly, recurrence sites could significantly affect recurrence time (P = 0.0062) and patients with recurrence in transplanted liver have longer recurrence time. In conclusions, we analyzed the relationships between NANOG/OCT4 expression, clinicopathology features, HCC recurrence, and OS after liver transplantation for the first time. Combination of NANOG, OCT4, LNM, histopathological stage, and MVI may be predictor for HCC recurrence posttransplantation. Comprehensive of histopathological stage grade and LNM were considered as prognosis factor for OS after liver transplantation. This should be helpful for treatment method selection for HCC patients after liver transplantation.  相似文献   
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Deregulated long noncoding RNAs (lncRNA) have been critically implicated in tumorigenesis and serve as novel diagnostic and prognostic biomarkers. Here we sought to develop a prognostic lncRNA signature in patients with head and neck squamous cell carcinoma (HNSCC). Original RNA-seq data of 499 HNSCC samples were retrieved from The Cancer Genome Atlas database, which was randomly divided into training and testing set. Univariate Cox regression survival analysis, robust likelihood-based survival model and random sampling iterations were applied to identify prognostic lncRNA candidates in the training cohort. A prognostic risk score was developed based on the Cox coefficient of four individual lncRNA imputed as follows: (0.14546 × expression level of RP11-366H4.1) + (0.27106 × expression level of LINC01123) + (0.54316 × expression level of RP11-110I1.14) + (−0.48794 × expression level of CTD-2506J14.1). Kaplan-Meier analysis revealed that patients with high-risk score had significantly reduced overall survival as compared with those with low-risk score when patients in training, testing, and validation cohorts were stratified into high- or low-risk subgroups. Multivariate survival analysis further revealed that this 4-lncRNA signature was a novel and important prognostic factor independent of multiple clinicopathological parameters. Importantly, ROC analyses indicated that predictive accuracy and sensitivity of this 4-lncRNA signature outperformed those previously well-established prognostic factors. Noticeably, prognostic score based on quantification of these 4-lncRNA via qRT-PCR in another independent HNSCC cohort robustly stratified patients into subgroups with high or low survival. Taken together, we developed a robust 4-lncRNA prognostic signature for HNSCC that might provide a novel powerful prognostic biomarker for precision oncology.  相似文献   
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As a first line medicine for malaria treatment, artesunate (ART) also shows antitumor potential. However, little is known about the effect of ART on the cancer cell epithelial-mesenchymal transition (EMT). In this study, we found that ART inhibited cell growth in SK-HEP1 and SM7721 hepatocellular carcinoma cell lines. A microarray was used to identify differentially expressed protein-coding RNAs (pcRNA) and long noncoding RNAs (lncRNA) between SK-HEP1 cells with and without ART treatment. A differentially expressed lncRNA—RP11, the most related to the EMT of liver cancer cells—RP11 was identified by abioinformatics method Overexpressing and silencing assays were used to verify the role of RP11 in cancer cell EMT. The levels of RP11- and EMT-related genes in liver cancer samples from 75 patients were detected by using qualitative polymerase chain reaction or immunohistochemistry. We identified 1334 pcRNAs and 1670 lncRNA with differential expression induced by ART. ART inhibits EMT, proliferation, migration, invasion, and adhesion of liver cancer cells. RP11 depresses the inhibitory effect of ART on cancer cell EMT. The level of RP11 is associated with cancer cell EMT and metastasis and survival rate of the patient. These data suggest that RP11-linking ART and cancer cell EMT are important for ART-inhibited metastasis of liver cancer.  相似文献   
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