目的:研究N-MYC下游调控基因4在宫颈癌细胞中的表达及其对宫颈癌细胞增殖、凋亡及周期的影响。方法:通过荧光实时定量聚合酶链反应和免疫印迹检测HeLa细胞中NDRG4的表达,构建NDRG4稳转细胞系HeLa-NDRG4。CCK-8法检测NDRG4对Hela细胞增...目的:研究N-MYC下游调控基因4在宫颈癌细胞中的表达及其对宫颈癌细胞增殖、凋亡及周期的影响。方法:通过荧光实时定量聚合酶链反应和免疫印迹检测HeLa细胞中NDRG4的表达,构建NDRG4稳转细胞系HeLa-NDRG4。CCK-8法检测NDRG4对Hela细胞增殖的影响,流式细胞术检测NDRG4对Hela细胞凋亡及周期的影响。结果:宫颈癌细胞中NDRG4 m RNA和蛋白表达水平均较人正常宫颈内皮细胞显著降低,HeLa-NDRG4细胞的增殖能力显著低于HeLa-MOCK细胞,而凋亡能力显著高于HeLa-MOCK细胞。与HeLa-MOCK细胞相比,HeLa-NDRG4细胞周期被阻滞于G1期。HeLa-NDRG4细胞中p-Akt的蛋白水平较HeLa-MOCK细胞显著降低,而PTEN的蛋白水平较HeLa-MOCK细胞显著升高。结论 :NDRG4在宫颈癌中作为抑癌基因发挥作用。展开更多
Colorectal cancer(CRC) is fourth most common cancer in men and third in women worldwide. Developing a diagnostic panel of sensitive and specific biomarkers for the early detection of CRC is recognised as to be crucial...Colorectal cancer(CRC) is fourth most common cancer in men and third in women worldwide. Developing a diagnostic panel of sensitive and specific biomarkers for the early detection of CRC is recognised as to be crucial for early initial diagnosis, which in turn leads to better long term survival. Most of the research on novel potential CRC biomarkers in the last 2 decades has been focussed on stool DNA analysis. In this paper, we describe the recent advances in non-invasive CRC screening and more specifically in molecular assays for aberrantly methylated BMP3 and NDRG4 promoter regions. In several research papers these markers showed superior rates for sensitivity and specificity in comparison to previously described assays. These tests detected the majority of adenomas ≥ 1 cm in size and the detection rates progressively increased with larger adenomas. The methylation status of the BMP3 and NDRG4 promoters demonstrated effective detection of neoplasms at all sites throughout the colon and was not affected by common clinical variables. Recently, a multitarget stool DNA test consisting of molecular assays for aberrantly methylated BMP3 and NDRG4 promoter regions, mutant KRAS and immunochemical assay for human haemoglobin has been made commercially available and is currently reimbursed in the United States. Although this is the most sensitive noninvasive CRC screening test, there is the need for further research in several areas- establishment of the best timeframe for repeated DNA stool testing; validation of the results in populations outside of North America; usefulness for surveillance and prognosis of patients; cost-effectiveness of DNA stool testing in real-life populations.展开更多
Bone defects and non-union are prevalent in clinical orthopedy,and the outcomes of current treatments are often suboptimal.Bone tissue engineering offers a promising approach to treating these conditions effectively.B...Bone defects and non-union are prevalent in clinical orthopedy,and the outcomes of current treatments are often suboptimal.Bone tissue engineering offers a promising approach to treating these conditions effectively.Bone morphogenetic protein 9(BMP9)can commit mesenchymal stem cells to osteogenic lineage,and a knowledge of the underlying mechanisms may help advance the field of bone tissue engineering.Leucine-rich repeats con-taining G protein-coupled receptor 4(LGR4),a member of G protein-coupled receptors,is essential for modulating bone development.This study is aimed at investigating the impact of LGR4 on BMP9-induced osteogenesis in mesenchymal stem cells as well as the underlying mechanisms.Bone marrow stromal cells from BMp9-knockout mice exhibited diminished LGR4 expression,and exogenous LGR4 clearly restored the impaired osteogenic potency of the bone marrow stromal cells.Furthermore,LGR4 expression was increased by BMP9 in C3H10T1/2 cells.LGR4 augmented the benefits of BMP9-induced osteogenic markers and bone formation,whereas LGR4 inhibition restricted these effects.Meanwhile,the BMP9-induced li-pogenic markers were increased by LGR4 inhibition.The protein levels of Raptor and p-Stat3 were elevated by BMP9.Raptor knockdown or p-Stat3 suppression attenuated the osteoblastic markers and LGR4 expression brought on by BMP9.LGR4 significantly reversed the blocking ef-fect of Raptor knockdown or p-Stat3 suppression on the BMP9-induced osteoblastic markers.Raptor interacts with p-Stat3,and p-Stat3 activates the LGR4 promoter activity.In conclusion,LGR4 boosts BMP9 osteoblastic potency in mesenchymal stem cells,and BMP9 may up-regulate LGR4 via the mTORC1/Stat3 signal activation.展开更多
Embryonic stem cells (ES cells) are derived from the inner cell mass (ICM) of blastocysts. ES cells can divide and produce identical copies of them over and over again (self-renewal) in vitro for a long time, and reta...Embryonic stem cells (ES cells) are derived from the inner cell mass (ICM) of blastocysts. ES cells can divide and produce identical copies of them over and over again (self-renewal) in vitro for a long time, and retain the capability of differentiating into all cell types when induced by appropriate signals. Their capability of multilineage dif- ferentiation might be exploited for cell-based therapies. Therefore, ES cells have a broad prospect in many clinical applications. To achieve success in the clinical applications, we have to understand how ES cells propagate and differen- tiate into specific cell types. The cytokine LIF can sustain the self-renewal of certain mouse ES cells (mES cells) through activation of the signal transduction pathway LIF/gp130/ STAT3. In this pathway the transcription factor STAT3 is a crucial factor. Furthermore, Oct-3/4 plays a very important role in maintaining the ES cell pluripotency. Oct-3/4 regu- lates embryo development through its co-factor Sox2 and Rox-1. Recently nanog, a new homeodomain gene, was found and it has been shown to be crucial for the renewal and pluripotency of ES cells. Three other signals BMP, Wnt and ERK also can influence differentiation and propagation of ES cells. This review article summarizes recent progress in this area, mainly focusing on the LIF signaling pathway and the transcription factors Oct-3/4 and Nanog. Although it is still unclear how these components cooperate, a model is presented here to provide a design for solving this problem.展开更多
文摘目的:研究N-MYC下游调控基因4在宫颈癌细胞中的表达及其对宫颈癌细胞增殖、凋亡及周期的影响。方法:通过荧光实时定量聚合酶链反应和免疫印迹检测HeLa细胞中NDRG4的表达,构建NDRG4稳转细胞系HeLa-NDRG4。CCK-8法检测NDRG4对Hela细胞增殖的影响,流式细胞术检测NDRG4对Hela细胞凋亡及周期的影响。结果:宫颈癌细胞中NDRG4 m RNA和蛋白表达水平均较人正常宫颈内皮细胞显著降低,HeLa-NDRG4细胞的增殖能力显著低于HeLa-MOCK细胞,而凋亡能力显著高于HeLa-MOCK细胞。与HeLa-MOCK细胞相比,HeLa-NDRG4细胞周期被阻滞于G1期。HeLa-NDRG4细胞中p-Akt的蛋白水平较HeLa-MOCK细胞显著降低,而PTEN的蛋白水平较HeLa-MOCK细胞显著升高。结论 :NDRG4在宫颈癌中作为抑癌基因发挥作用。
文摘Colorectal cancer(CRC) is fourth most common cancer in men and third in women worldwide. Developing a diagnostic panel of sensitive and specific biomarkers for the early detection of CRC is recognised as to be crucial for early initial diagnosis, which in turn leads to better long term survival. Most of the research on novel potential CRC biomarkers in the last 2 decades has been focussed on stool DNA analysis. In this paper, we describe the recent advances in non-invasive CRC screening and more specifically in molecular assays for aberrantly methylated BMP3 and NDRG4 promoter regions. In several research papers these markers showed superior rates for sensitivity and specificity in comparison to previously described assays. These tests detected the majority of adenomas ≥ 1 cm in size and the detection rates progressively increased with larger adenomas. The methylation status of the BMP3 and NDRG4 promoters demonstrated effective detection of neoplasms at all sites throughout the colon and was not affected by common clinical variables. Recently, a multitarget stool DNA test consisting of molecular assays for aberrantly methylated BMP3 and NDRG4 promoter regions, mutant KRAS and immunochemical assay for human haemoglobin has been made commercially available and is currently reimbursed in the United States. Although this is the most sensitive noninvasive CRC screening test, there is the need for further research in several areas- establishment of the best timeframe for repeated DNA stool testing; validation of the results in populations outside of North America; usefulness for surveillance and prognosis of patients; cost-effectiveness of DNA stool testing in real-life populations.
文摘目的 研究骨形态发生蛋白4(bone morphogenetic protein-4,BMP4)、胰岛素样生长因子-I(insulin-like growth factor-I,IGF-I)、转移生长因子-β3(transforming growth factorβ3,TGF-β3)、睾酮对鹿茸间充质细胞增殖和分化的作用,探讨鹿茸生长的机理。方法 体外分离培养鹿茸间充质细胞,采用MTT法测定BMP4、IGF-I对不同代次鹿茸间充质细胞的增殖作用,以及与不同浓度的睾酮组合对鹿茸间充质细胞增殖活性的影响;采用免疫荧光、阿尔新蓝染色、实时荧光PCR法检测分化诱导培养7、14、21 d的鹿茸间充质细胞中II、X、I型胶原蛋白(Collagen type II、Collagen type X、Collagen type I,COLII、COLX、COLI)和聚集蛋白聚糖的变化,考察BMP4、TGF-β3和睾酮对鹿茸间充质细胞向软骨分化的影响。结果 BMP4可提高鹿茸间充质细胞的增殖活性,且明显高于IGF-I,并与IGF-I有协同促进作用。早期、传代次数较少的幼嫩鹿茸间充质细胞对BMP4较敏感。不同浓度的睾酮,均显著抑制了BMP4的促增殖作用,尤其是生理浓度睾酮抑制作用最强。软骨诱导分化培养3 d鹿茸间充质细胞扁平膨大,形态发生明显变化,7 d COLII免疫荧光试验均阳性;14 d细胞集聚呈团,阿尔新蓝染色阳性;21 d BMP4提升COLII表达,具有一定的促进鹿茸间充质细胞成软骨分化的作用,并与睾酮、TGF-β3有协同促进作用,BMP4单独作用主要表现在提升COLX、COLI的表达量,促细胞肥大、成骨分化;生理浓度的睾酮不影响COLX表达,但降低了COLI的表达量;TGF-β3能诱导COLII表达,降低了COLX、COLI的表达量,显著减弱BMP4的促软骨细胞肥大和促成骨分化作用,而睾酮对TGF-β3的这个抑制作用无明显影响。结论 BMP4、IGF-I、TGF-β3和睾酮在鹿茸增殖、分化为软骨细胞、软骨内成骨的不同生长发育阶段中发挥着相互协同或抑制的作用。
基金All animal experiments were approved by The Ethics Committee of Chongqing Medical University(No.2022030).
文摘Bone defects and non-union are prevalent in clinical orthopedy,and the outcomes of current treatments are often suboptimal.Bone tissue engineering offers a promising approach to treating these conditions effectively.Bone morphogenetic protein 9(BMP9)can commit mesenchymal stem cells to osteogenic lineage,and a knowledge of the underlying mechanisms may help advance the field of bone tissue engineering.Leucine-rich repeats con-taining G protein-coupled receptor 4(LGR4),a member of G protein-coupled receptors,is essential for modulating bone development.This study is aimed at investigating the impact of LGR4 on BMP9-induced osteogenesis in mesenchymal stem cells as well as the underlying mechanisms.Bone marrow stromal cells from BMp9-knockout mice exhibited diminished LGR4 expression,and exogenous LGR4 clearly restored the impaired osteogenic potency of the bone marrow stromal cells.Furthermore,LGR4 expression was increased by BMP9 in C3H10T1/2 cells.LGR4 augmented the benefits of BMP9-induced osteogenic markers and bone formation,whereas LGR4 inhibition restricted these effects.Meanwhile,the BMP9-induced li-pogenic markers were increased by LGR4 inhibition.The protein levels of Raptor and p-Stat3 were elevated by BMP9.Raptor knockdown or p-Stat3 suppression attenuated the osteoblastic markers and LGR4 expression brought on by BMP9.LGR4 significantly reversed the blocking ef-fect of Raptor knockdown or p-Stat3 suppression on the BMP9-induced osteoblastic markers.Raptor interacts with p-Stat3,and p-Stat3 activates the LGR4 promoter activity.In conclusion,LGR4 boosts BMP9 osteoblastic potency in mesenchymal stem cells,and BMP9 may up-regulate LGR4 via the mTORC1/Stat3 signal activation.
文摘Embryonic stem cells (ES cells) are derived from the inner cell mass (ICM) of blastocysts. ES cells can divide and produce identical copies of them over and over again (self-renewal) in vitro for a long time, and retain the capability of differentiating into all cell types when induced by appropriate signals. Their capability of multilineage dif- ferentiation might be exploited for cell-based therapies. Therefore, ES cells have a broad prospect in many clinical applications. To achieve success in the clinical applications, we have to understand how ES cells propagate and differen- tiate into specific cell types. The cytokine LIF can sustain the self-renewal of certain mouse ES cells (mES cells) through activation of the signal transduction pathway LIF/gp130/ STAT3. In this pathway the transcription factor STAT3 is a crucial factor. Furthermore, Oct-3/4 plays a very important role in maintaining the ES cell pluripotency. Oct-3/4 regu- lates embryo development through its co-factor Sox2 and Rox-1. Recently nanog, a new homeodomain gene, was found and it has been shown to be crucial for the renewal and pluripotency of ES cells. Three other signals BMP, Wnt and ERK also can influence differentiation and propagation of ES cells. This review article summarizes recent progress in this area, mainly focusing on the LIF signaling pathway and the transcription factors Oct-3/4 and Nanog. Although it is still unclear how these components cooperate, a model is presented here to provide a design for solving this problem.
