调控骨肉瘤及干细胞的相关信号通路

文题释义： 骨肉瘤：是多发于儿童和青少年的原发恶性骨肿瘤,恶性程度高,容易发生转移,预后不良。骨肉瘤的复发、转移及多药耐药,是制约骨肉瘤治疗效果的主要问题。 信号通路：是指能将细胞外的分子信号经细胞膜传入细胞内发挥效应的一系列酶促反应通路,在骨肉瘤的发生、增殖和侵袭中发挥重要作用。 背景：骨肉瘤是儿童和青少年中最常见的原发性骨源性恶性肿瘤,过去30年骨肉瘤患者的预后几乎没有大的进步,迫切需要开发新的策略和创新疗法,以进一步提高骨肉瘤患者的生存率。 目的：阐述骨肉瘤进展和转移的分子机制和信号传导网络的最新进展,为治疗骨肉瘤提供一定的理论基础。 方法：以“骨肉瘤,信号通路,预后,转移,耐药,Notch,Wnt/β-catenin,Hedgehog,PI3K/Akt/mTOR,BMPs”为中文检索词,以“osteosarcoma,signaling pathway,prognosis,metastasis,drug resistance,Notch,Wnt/β-catenin,Hedgehog,PI3K/Akt/mTOR,BMPs”为英文检索词,应用计算机在CNKI、PubMed 数据库检索1999年2月至2019年2月相关文献共586篇。通过阅读文献标题和摘要进行筛选,按排除标准剔除不相关的文献,最后共纳入40篇文献进行综述。 结果与结论：信号通路在骨肉瘤的形成和增殖调控方面非常重要,研究发现Notch、Wnt/β-catenin、Hedgehog、PI3K/Akt/mTOR和BMP等信号通路在骨肉瘤及骨肉瘤干细胞中均有表达,对骨肉瘤的发生发展产生重要影响。 ORCID: 0000-0003-4489-9647(陶海) 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

薄膜分散-超声法制备BMPs磁性脂质体

目的 采用薄膜分散-超声法制备磁性颗粒(bacterial magnetic particles,BMPs)脂质体,考察BMPs浓度、超声功率和超声时间等因素对BMPs磁性脂质体粒径的影响.方法 薄膜分散-超声法制备BMPs脂质体,调节BMPs浓度、超声功率和超声时间等因素,激光散射粒度仪测定磁性脂质体粒径.结果 以薄膜分散-超声法制备的BMPs脂质体,BMPs浓度在(20～60)μg/mL时,磁性脂质体粒径基本稳定,平均94.9nm;BMPs浓度在(60～100)μg/mL时,磁性脂质体粒径随着BMPs浓度增加而有增大的趋势.超声功率的增加或超声有效时间增大时,磁性脂质体的平均粒径有减小趋势,当超声功率为300W、有效超声时间为100s时,粒径出现最小值;但其后都存在转折,随着超声功率的再增加或超声有效时间再增大时,平均粒径反而出现增大现象.结论薄膜分散-超声法制备BMPs脂质体,通过控制BMPs浓度、超声功率和超声时间等因素,可以对磁性脂质体粒径进行调节.     

复合BMP同种异体半关节异位植入的免疫研究

目的探讨B M P骨诱导与免疫反应之间的关系。方法将复合B M P5m g的冻干异体半关节植入兔腰大肌肌袋内,并采用原位杂交技术对术后不同时间各组IL-1和IL-6m R N A表达强度进行比较。结果骨移植术后,实验组较对照组成骨作用增强。植骨局部在移植术后第4周起即可见IL-1和IL-6m R N A的阳性表达,实验组与对照组植骨局部均可见IL-1和IL-6m R N A的阳性表达,不同时间点各组间IL-1和IL-6m R-N A表达强度无明显差异。结论B M P作为外源性介质,在异位发挥诱导成骨作用的同时并不加重免疫排斥反应。     

TGFβ Regulation of Perilacunar/Canalicular Remodeling Is Sexually Dimorphic

Bone fragility is the product of defects in bone mass and bone quality, both of which show sex-specific differences. Despite this, the cellular and molecular mechanisms underpinning the sexually dimorphic control of bone quality remain unclear, limiting our ability to effectively prevent fractures, especially in postmenopausal osteoporosis. Recently, using male mice, we found that systemic or osteocyte-intrinsic inhibition of TGFβ signaling, achieved using the 9.6-kb DMP1 promoter-driven Cre recombinase (TβRII^ocy−/− mice), suppresses osteocyte perilacunar/canalicular remodeling (PLR) and compromises bone quality. Because systemic TGFβ inhibition more robustly increases bone mass in female than male mice, we postulated that sex-specific differences in bone quality could likewise result, in part, from dimorphic regulation of PLR by TGFβ. Moreover, because lactation induces PLR, we examined the effect of TGFβ inhibition on the female skeleton during lactation. In contrast to males, female mice that possess an osteocyte-intrinsic defect in TGFβ signaling were protected from TGFβ-dependent defects in PLR and bone quality. The expression of requisite PLR enzymes, the lacunocanalicular network (LCN), and the flexural strength of female TβRII^ocy−/− bone was intact. With lactation, however, bone loss and induction in PLR and osteocytic parathyroid hormone type I receptor (PTHR1) expression, were suppressed in TβRII^ocy−/− bone, relative to the control littermates. Indeed, differential control of PTHR1 expression, by TGFβ and other factors, may contribute to dimorphism in PLR regulation in male and female TβRII^ocy−/− mice. These findings provide key insights into the sex-based differences in osteocyte PLR that underlie bone quality and highlight TGFβ signaling as a crucial regulator of lactation-induced PLR. © 2020 American Society for Bone and Mineral Research.     

Intramuscular bone induction by human recombinant bone morphogenetic protein-2 with beta-tricalcium phosphate as a carrier: in vivo bone banking for muscle-pedicle autograft

 An ideal replacement for bone defects is auto-bone tissue, of which there is an ample supply with the required form and with vascularity. Our strategy for generating such bone tissue is as follows. First, bone tissue is induced in muscle by bone morphogenetic protein-2 (BMP-2) with beta-tricalcium phosphate as a carrier to maintain its form in the muscle. Second, the induced bone in the muscle pedicle is grafted to the bone defect to maintain vascularity. In the first experiment, 50 μg of recombinant human BMP-2 (rhBMP-2) was inoculated into the hip abductor muscle of rabbits with beta-tricalcium phosphate under anesthesia. Five weeks after the operation, intramuscular bone formation was observed in all of the samples, and the form and size of the induced bone tissue were identical to those of the carrier. Ten weeks after the operation, the induced bone was partly absorbed. In the second experiment, 50 μg of rhBMP-2 was inoculated in the same manner as previously. Five weeks after the operation, the muscle tissue around the induced bone was incised, leaving just the proximal part as a pedicle. Two or four weeks after the second operation, the induced bone tissue had rich vascularity and no empty lacunae. This indicates the possibility of in vivo bone banking to enable morphologically controlled and vascularized auto-bone grafts. Received: December 21, 2001 / Accepted: March 28, 2002     

龟板提取物靶向BMP4通路抑制PC12细胞凋亡

目的探讨龟板提取物(Testudinis Carapax et Plastrum extracts,TCPE)对血清饥饿诱导的PC12细胞凋亡的保护作用及其机制。方法采用血清饥饿3 d的方法建立PC12细胞凋亡模型,并将细胞分为对照组,模型组,TCPE低、高剂量(3、30μg/mL)组。在施加处理因素3 d后,用MTT比色分析测定细胞吸光度值,Annexin V/PI双染流式细胞术测定细胞凋亡率,Western blotting检测Caspase-3、BMPs信号通路的表达水平,并检测BMPs信号通路阻断后TCPE的抗凋亡作用。用Bio-Rad Quantity One凝胶分析系统对条带进行半定量分析。结果 MTT与流式细胞术结果显示,TCPE能提高PC12细胞活性,降低PC12细胞凋亡率,并呈剂量依赖性,TCPE组与模型组相比差异具有统计学意义(P<0.05、0.01)。Western blotting结果显示,TCPE能降低Caspase-3表达,增加BMP4、BMPR-IA、p-Smad1/5/8的表达,TCPE组与模型组相比,差异具有统计学意义(P<0.05、0.01)。TCPE对BMP2、BMP7、BMPR-II的表达没有影响,BMPR-IB没有被检测出。BMP4中和抗体减弱了TCPE的抗凋亡活性。结论 TCPE具有抑制血清饥饿诱导PC12细胞凋亡的作用,且这种作用呈剂量依赖性,其作用机制可能与激活BMP4信号通路表达有关。     

Bone morphogenetic protein 4 inhibits TGF‐β2 stimulation of extracellular matrix proteins in optic nerve head cells: Role of gremlin in ECM modulation

The characteristic cupping of the optic nerve head (ONH) in glaucoma is associated with elevated TGF‐β2 and increased synthesis and deposition of extracellular matrix (ECM) proteins. In addition to TGF‐β2, the human ONH also expresses bone morphogenetic proteins (BMPs) and BMP receptors, which are members of the TGF‐β superfamily. We examined the potential effects of BMP4 and the BMP antagonist gremlin on TGF‐β2 induction of ECM proteins in ONH cells. BMP‐4 dose dependently inhibited TGF‐β2‐induced fibronectin (FN) and PAI‐1 expression in ONH astrocytes and lamina cribrosa (LC) cells and also reduced TGF‐β2 stimulation of collagen I, collagen VI, and elastin. Addition of gremlin blocked this BMP‐4 response, increasing cellular and secreted FN as well as PAI‐1 levels in both cell types. Gremlin was expressed in ONH tissues and ONH cells, and gremlin protein levels were significantly increased in the LC region of human glaucomatous ONH tissues. Interestingly, recombinant gremlin dose dependently increased ECM protein expression in cultured ONH astrocytes and LC cells. Gremlin stimulation of ECM required activation of TGF‐β receptor and R‐Smad3. TGF‐β2 increased gremlin mRNA expression and protein levels in ONH cells. Inhibition of either the type I TGF‐β receptor or Smad3 phosphorylation blocked TGF‐β2‐induced gremlin expression. In conclusion, BMP4 blocked the TGF‐β2 induction of ECM proteins in ONH cells. The BMP antagonist gremlin reversed this inhibition, allowing TGF‐β2 stimulation of ECM synthesis. Increased expression of gremlin in the glaucomatous ONH may further exacerbate TGF‐β2 effects on ONH ECM metabolism by inhibiting BMP‐4 antagonism of TGF‐β2 signaling. Modulation of the ECM via gremlin provides a novel therapeutic target for glaucoma. © 2008 Wiley‐Liss, Inc.     

成年大鼠睾丸Smad1和Smad5的免疫组织化学研究

目的 :探讨骨形态形成蛋白的细胞内信号传导分子Smad1和Smad5蛋白在成年大鼠睾丸内的表达。　方法 :应用免疫组织化学ABC法结合葡萄糖氧化酶 DAB 硫酸镍铵增强技术 ,检测成年大鼠睾丸Smad1和Smad5蛋白的表达和定位。　结果 :Smad1蛋白表达于大鼠睾丸精曲小管的各级生精细胞的胞质内 ,呈淡染的紫蓝色颗粒 ,胞核为阴性 ,免疫染色阳性细胞主要包括精原细胞、初级精母细胞、次级精母细胞和精子细胞 ;而Smad5蛋白阳性染色不明显 ,只有睾丸间质细胞呈弱阳性反应 ,免疫反应阳性物质主要定位于细胞质。　结论 :Smad1蛋白主要表达于睾丸精曲小管各级生精细胞 ,Smad5蛋白表达于间质细胞 ,为揭示TGF β超家族在精子发生中的分子机理提供了直接证据。     

BMPs信号通路与乳腺癌发生、发展的研究进展

BMPs属于转化生长因子-β超家族,在介导细胞增殖、凋亡、迁移、分化等方面发挥了重要作用。BMPs异常表达、紊乱在肿瘤发生、发展过程中的作用为目前的一大研究热点,本文着重探讨了BMPs信号通路的紊乱及其甲基化在乳腺癌变过程中发挥的作用。     

可同时释放两种骨形态发生蛋白复合支架的制备

目的 研制一种可同时释放骨形态发生蛋白2 (BMP-2)和骨形态发生蛋白7(BMP-7)的生物活性复合支架,以应用于骨组织工程的研究.方法 分别采用复乳溶剂挥发法和相分离法制备负载BMP-2和BMP-7的聚乳酸/羟基乙酸-聚乙二醇(PGLA-PEG)微球和三维多孔的聚己内酯(PCL)支架.然后采用改良的二氯甲烷熏蒸法将PGLA-PEG微球黏附在PCL支架上,形成同时负载BMP-2和BMP-7的复合支架,并检测BMP-2和BMP-7的缓释效果.将人成骨细胞系hFOB1.19分别种植在复合支架和传统支架中,研究支架上的细胞增殖能力和成骨分化能力.结果 制备的复合支架能同时缓慢地释放BMP-2和BMP-7.细胞培养第10天,复合支架上的细胞活性优于传统支架(P＜0.01),细胞形态正常.复合支架上细胞的碱性磷酸酶和Ⅰ型胶原蛋白、骨钙素、骨桥蛋白3种成骨基因的mRNA水平均高于传统支架(P＜0.05,P＜0.01).结论 成功研制出一种可同时释放BMP-2和BMP-7的生物活性复合支架,并可用于骨组织工程的研究.