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771.
Long non-coding RNAs (lncRNAs) have been highlighted as attractive markers for diagnosis and prognosis as well as new therapeutic targets in multiple cancers, including nasopharyngeal carcinoma (NPC). Here, we attempted to investigate the underlying regulatory role of the lncRNA maternally expressed gene 3 (MEG3) in NPC development. As determined by RT-qPCR, MEG3 expression was down-regulated in NPC cells. Online RNA crosstalk analysis predicted the binding of miR-21 to MEG3 and PTEN, respectively. MEG3 was validated to bind to miR-21 while PTEN was identified as a target of miR-21 by dual-luciferase reporter gene assay. Exogenous transfection was done to change the levels of MEG3, miR-21 and PTEN in HK-1 cells to investigate their effects on the autophagy and apoptosis of NPC cells. The results suggested that MEG3 overexpression in HK-1 cells up-regulated PTEN and down-regulated miR-21, by which MEG3 further inhibited autophagy and apoptosis ability of NPC cells. The tumour formation ability was tested after injecting the HK-1 cells into nude, mice and tumour growth was monitored. Consistently, MEG3 overexpression inhibited the tumour formation in vivo. Collectively, MEG3 promotes the autophagy and apoptosis of NPC cells via enhancing PTEN expression by binding to miR-21. 相似文献
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774.
Zhentao Yang Liang Zhang Hai Zhu Ke Zhou Hangxiang Wang Yuchen Wang Rong Su Danjing Guo Lin Zhou Xiao Xu Penghong Song Shusen Zheng Haiyang Xie 《Journal of cellular and molecular medicine》2021,25(7):3511-3523
Hepatocellular carcinoma (HCC) is one of the most aggressive tumours with marked fibrosis. Mycophenolate mofetil (MMF) was well-established to have antitumour and anti-fibrotic properties. To overcome the poor bioavailability of MMF, this study constructed two MMF nanosystems, MMF-LA@DSPE-PEG and MMF-LA@PEG-PLA, by covalently conjugating linoleic acid (LA) to MMF and then loading the conjugate into polymer materials, PEG5k-PLA8k and DSPE- PEG2k, respectively. Hepatocellular carcinoma cell lines and C57BL/6 xenograft model were used to examine the anti-HCC efficacy of nanoparticles (NPs), whereas NIH-3T3 fibroblasts and highly-fibrotic HCC models were used to explore the anti-fibrotic efficacy. Administration of NPs dramatically inhibited the proliferation of HCC cells and fibroblasts in vitro. Animal experiments revealed that MMF-LA@DSPE-PEG achieved significantly higher anti-HCC efficacy than free MMF and MMF-LA@PEG-PLA both in C57BL/6 HCC model and highly-fibrotic HCC models. Immunohistochemistry further confirmed that MMF-LA@DSPE-PEG dramatically reduced cancer-associated fibroblast (CAF) density in tumours, as the expression levels of alpha-smooth muscle actin (α-SMA), fibroblast activation protein (FAP) and collagen IV were significantly downregulated. In addition, we found the presence of CAF strongly correlated with increased HCC recurrence risk after liver transplantation. MMF-LA@DSPE-PEG might act as a rational therapeutic strategy in treating HCC and preventing post-transplant HCC recurrence. 相似文献
775.
Wei Liu Chunyu Wang Shengli Wang Kai Zeng Shan Wei Ning Sun Ge Sun Manlin Wang Renlong Zou Wensu Liu Lin Lin Huijuan Song Zining Jin Yue Zhao 《International journal of biological sciences》2021,17(1):188
Androgen receptor (AR) and its variants play vital roles in development and progression of prostate cancer. To clarify the mechanisms involved in the enhancement of their actions would be crucial for understanding the process in prostate cancer and castration-resistant prostate cancer transformation. Here, we provided the evidence to show that pre-mRNA processing factor 6 (PRPF6) acts as a key regulator for action of both AR full length (AR-FL) and AR variant 7 (AR-V7), thereby participating in the enhancement of AR-FL and AR-V7-induced transactivation in prostate cancer. In addition, PRPF6 is recruited to cis-regulatory elements in AR target genes and associates with JMJD1A to enhance AR-induced transactivation. PRPF6 also promotes expression of AR-FL and AR-V7. Moreover, PRPF6 depletion reduces tumor growth in prostate cancer-derived cell lines and results in significant suppression of xenograft tumors even under castration condition in mouse model. Furthermore, PRPF6 is obviously highly expressed in human prostate cancer samples. Collectively, our results suggest PRPF6 is involved in enhancement of oncogenic AR signaling, which support a previously unknown role of PRPF6 during progression of prostate cancer and castration-resistant prostate cancers. 相似文献
776.
Hong Zhou Xu-dong Zheng Chang-ming Lin Jie Min Shuang Hu Ying Hu Liang-yun Li Jia-si Chen Yu-min Liu Hao-dong Li Xiao-ming Meng Jun Li Ya-ru Yang Tao Xu 《International journal of biological sciences》2021,17(2):651
Prostate cancer (PC) is the most common carcinoma among men worldwide which results in 26% of leading causes of cancer-related death. However, the ideal and effective molecular marker remains elusive. CircRNA, initially observed in plant-infected viruses and Sendai virus in 1979, is generated from pre-mRNA back-splicing and comes in to play by adequate expression. The differential expression in prostate tissues compared with the control reveals the promising capacity in modulating processes including carcinogenesis and metastasis. However, the biological mechanisms of regulatory network in PC needs to systemically concluded. In this review, we enlightened the comprehensive studies on the definite mechanisms of circRNAs affecting tumor progression and metastasis. What''s more, we validated the potential clinical application of circRNAs serving as diagnostic and prognostic biomarker. The discussion and analysis in circRNAs will broaden our knowledge of the pathogenesis of PC and further optimize the current therapies against different condition. 相似文献
777.
Jun Zuo Lili Hu Wei Shen Jiaying Zeng Lin Li Lirong Song Nanqin Gan 《Environmental microbiology》2021,23(2):1066-1078
Lake Taihu in China has suffered serious harmful cyanobacterial blooms for decades. The algal blooms threaten the ecological sustainability, drinking water safety, and human health. Although the roles of abiotic factors (such as water temperature and nutrient loading) in promoting Microcystis blooms have been well studied, the importance of biotic factors (e.g. bacterial community) in promoting and meditating Microcystis blooms remains unclear. In this study, we investigated the ecological dynamics of bacterial community, the ratio of toxic Microcystis, as well as microcystin in Lake Taihu. High-throughput 16S rRNA sequencing and principal component analysis (PCA) revealed that the bacteria community compositions (BCCs) clustered into three groups, the partitioning of which corresponded to that of groups according to the toxic profiles (the ratio of toxic Microcystis to total Microcystis, and the microcystin concentrations) of the samples. Further Spearman's correlation network showed that the α-proteobacteria Phenylobacterium strongly positively correlated with the toxic profiles. Subsequent laboratory chemostats experiments demonstrated that three Phenylobacterium strains promoted the dominance of the toxic Microcystis aeruginosa PCC7806 when co-culturing with the non-toxic PCC7806 mcyB− mutant. Taken together, our data suggested that the α-proteobacteria Phenylobacterium may play a vital role in the maintenance of toxic Microcystis dominance in Lake Taihu. 相似文献
778.
Liu Yue Sun Jiandong Su Yang Lin Jianmin Lv Chengyu Mo Kaien Xu Songhua Wang Shie 《Journal of molecular histology》2021,52(5):965-973
Journal of Molecular Histology - Preimplantation embryo development is characterized by drastic nuclear reprogramming and dynamic stage-specific gene expression. Key regulators of this earliest... 相似文献
779.
Li Zhenzi Liu Pan Yuan Yanan Liang Xiaoxiao Lei Jun Zhu Xiaobin Zhang Zuoqi Cai Lin 《Biomechanics and modeling in mechanobiology》2021,20(5):2013-2030
Biomechanics and Modeling in Mechanobiology - Osteoporosis (OP), a skeletal disease making bone mechanically deteriorate and easily fracture, is a global public health issue due to its high... 相似文献
780.
中国建立国家公园的目的是保护自然生态系统的完整性和原真性, 促进生物多样性保护。国家公园的完整性和原真性评价是国家公园的布局规划、边界范围确定以及功能区划等研究的前提条件。为了评估国家公园自然生态系统完整性和原真性状态, 本文基于陆地自然生态系统的结构和功能, 通过指标筛选、专家咨询、指标量化和建立综合评价模型, 构建了陆地自然生态系统完整性与原真性的评价指标体系及其量化评价方法。该评价方法包括5个自然生态系统完整性指标、5个自然生态系统原真性指标和2个综合评价指标。以浙江省钱江源国家公园体制试点为例, 本文初步评估了其生态系统完整性与原真性状态, 并对评价结果进行了分级。按照本研究的评价方法, 钱江源国家公园体制试点的自然生态系统完整性评价结果为52.83%, 评价等级为较差; 自然生态系统原真性评价结果为87.06%, 评价等级为好。钱江源国家公园体制试点有待关注和提升的指标有保护区域完整性指数(27.00%)和旗舰种适宜生境完整性指数(53.04%)。最后, 本文结合研究区域评价结果对生态系统完整性和原真性领域应关注的问题进行了讨论。该自然生态系统完整性和原真性评价方法可提供一种评价指标覆盖较全面、数据易获取, 且评价结果易被决策者和管理者理解的评价思路。 相似文献