双功能域重组FN多肽抑制癌细胞浸润能力的研究

在制备了两个Cell Ⅰ-Hep Ⅱ 双结构域重组FN多肽(CH50和CH56)的基础上,研究其抑制肿瘤细胞浸润能力的作用。两个多肽的结构差异是CH50中删除了Cell I和HepⅡ之间的Ⅲ-11和ED-A结构顺序。CH50(ED_(50)为30.2 nmol/L)结合细胞的能力略高于CH56(ED_(50)为45.4 nmol/L)。两种多肽均可显著抑制黑色素瘤B16/F1细胞结合层粘素的能力,抑制作用相同。在体内肿瘤浸润抑制试验中,两种多肽均可显著抑制癌细胞浸润能力,使肺转移结节数降低80％左右。结果提示:Ⅲ-11和ED-A结构顺序对Cell Ⅰ-Hep Ⅱ 双结构域多肽结合细胞的能力有一定的影响,但删除Ⅲ-11和ED-A不是重组多肽抑制肿瘤转移的决定因素,Cell I和Hep Ⅱ 这两个结构域单独连接在一起是其抑制肿瘤细胞转移的结构基础。     

NIH 3T3细胞转化前后细胞骨架及细胞表面纤维粘连蛋白的免疫荧光观察

本实验用抗纤维粘连蛋白(FN)亲和层析纯抗体和抗管蛋白抗体及鬼笔环肽,以免疫荧光组织化学方法,对NIH3T3细胞转染人肺腺癌细胞系AGZY基因组DNA前后细胞表面FN及细胞内骨架系统进行染色观察。结果表明,细胞在发生转化后,微丝及微管均表现出明显受损,细胞骨架结构不清,呈现为弥散样荧光;细胞表面FN大量减少,仅及正常NIH3T3细胞的1/9,其分布也由细丝形成的网状,变成斑点或斑块状。这一结果进一步证实,细胞恶变是涉及到细胞骨架系统及膜表面糖蛋白变化的复杂过程,并预示这些变化可能就是导致细胞形态发生变化、细胞失去正常生长调控的原因之一。     

Mucosal bromodomain-containing protein 4 mediates aeroallergen-induced inflammation and remodeling

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Fructosamine-6-phosphates are deglycated by phosphorylation to fructosamine-3,6-bisphosphates catalyzed by fructosamine-3-kinase (FN3K) and/or fructosamine-3-kinase-related-protein (FN3KRP)

Nonenzymatic glycation of proteins and some phospholipids by glucose and other reducing sugars (a.k.a Maillard reaction) is an unavoidable result of the coexistence of these sugars and the affected macromolecules in living systems. The consequences of this process are deleterious both in the intracellular and extracellular environments as evidenced by the close association between increased nonenzymatic glycation and complications of diabetes. Because of these considerations, we have proposed that the intrinsic toxicity of glucose and other sugars is counteracted in vivo by active deglycation mechanisms including transglycation of Schiff's bases and FN3K-dependent breakdown of fructosamines. While this modified hypothesis is receiving increasing experimental support, several issues regarding glycation/deglycation remain unresolved. Two such important questions are In this paper we propose a resolution of both these quandaries by proposing that fructosamine-6-phosphates are deglycated by phosphorylation to fructosamine-3,6-bisphosphates catalyzed by FN3KRP and/or possibly FN3K. We provide some preliminary evidence in support of this hypothesis and outline experimental approaches for definitive tests of this hypothesis. The potential medical implications of this finding are not clear yet but, if correct, this observation is likely to have a major impact on our understanding of the very basic and hitherto unexplored aspect of glucose metabolism and chemistry in vivo. One can imagine that, at some point in the future, measurement of FN3K/FN3KRP activity may be of diagnostic value in assessing an individual's susceptibility to diabetic complications. Further down the road, one can also envision a gene therapeutic intervention to bolster FN3K/FN3KRP-based antiglycation defenses.     

Polymer hydration and stiffness at biointerfaces and related cellular processes

The direct and indirect (by changing mechanical properties) effects of hydration at interfaces on cellular processes and tissue diseases are reviewed. The essential effect of substrate stiffness on cellular processes was demonstrated in the last decade. The combined effect of surface stiffness and hydration at interfaces has garnered much less attention, though hydration and dehydration play important roles in biological processes. This review focuses on the studies that demonstrate how hydration affects biological processes at interfaces. Elevated sodium and dehydration stimulate inflammatory signaling in endothelial cells and promote atherosclerosis. Various types of implant and blood contacting device coatings with varied surface stiffness and hydration have been reported. Effect of hydration on polymer modulus of elasticity and viscoelasticity was discussed taking into account cells adhesion, migration, proliferation, differentiation on surfaces with various degree of hydration. Future directions of research were considered, including the use of nanotechnology to regulate the hydration degree.     

Nanofiber technology in the ex vivo expansion of cord blood-derived hematopoietic stem cells

Umbilical cord blood (CB) can be used as an alternative source of hematopoietic stem cells (HSCs) for transplantation in hematological and non-hematological disorders. Despite several recognized advantages the limited cell number in CB one unit still restricts its clinical use. The success of transplantation greatly depends on the levels of total nucleated cell and CD34+ cell counts. Thus, many ex vivo strategies have been developed within the last decade in order to solve this obstacle, with more or less success, mainly determined by the degree of difficulty related with maintaining HSCs self-renewal and stemness properties after long-term expansion. Different research groups have developed very promising and diverse CB-derived HSC expansion strategies using nanofiber scaffolds. Here we review the state-of-the-art of nanofiber technology-based CB-derived HSC expansion.     

Pediatric inflammatory myofibroblastic tumor of the bladder with ALK–FN1 fusion successfully treated by alectinib

An inflammatory myofibroblastic tumor (IMT) is a mesenchymal neoplasm characterized by the proliferation of myofibroblasts and inflammatory cell infiltration. Although radical resection is the only established treatment strategy for IMT, it can cause functional disorders when vital organs are affected. We describe a case of pediatric IMT of the bladder with FN1–ALK (fibronectin 1–anaplastic lymphoma kinase) fusion. Radical resection might lead to urinary disturbance due to the large tumor size at diagnosis. However, the tumor was successfully treated with alectinib, a second-generation ALK inhibitor, followed by transurethral resection of the bladder tumor without any complications.     

大黄酚对单侧输尿管梗阻模型大鼠肾组织CTGF、α-SMA和FN的影响

目的探讨大黄酚对大鼠单侧输尿管梗阻模型(UUO)肾间质纤维化的影响。方法 27只SD大鼠随机分为假手术组、模型组、大黄酚组。用单侧输尿管梗阻术建立肾间质纤维化模型,大黄酚治疗14 d后检测血肌酐、尿素氮水平;采用免疫组织化学方法观察肾组织结缔组织生长因子(CTGF)、α-平滑肌肌动蛋白(α-SMA)、纤维连接蛋白(FN)的表达情况。结果与假手术组相比,模型组血肌酐、尿素氮的水平以及CTGF、α-SMA、FN的表达均显著增高。与模型组相比,大黄酚组血肌酐、尿素氮水平降低,CTGF、α-SMA、FN的阳性表达显著下调。结论大黄酚可能通过抑制UUO大鼠肾组织CTGF、α-SMA、FN的表达,从而缓解肾间质纤维化的发生发展。     

Retinoic acid remodels extracellular matrix (ECM) of cultured human fetal palate mesenchymal cells (hFPMCs) through down-regulation of TGF-β/Smad signaling

The regulation of extracellular matrix (ECM) by retinoic acid (RA) is interesting in light of the fact that the ECM plays an essential role in morphogenesis and palatal shelf elevation. In the current study, we explored the effect of RA overexposure on ECM and the probable mechanisms in cultured human fetal palate mesenchymal cells (hFPMCs). RA dose-dependently inhibited cell proliferation and mRNA and protein levels of ECM components fibronectin, tenascin C and fibrillin-2. Zymography revealed that MMP-2 activity was suppressed by RA. Further analysis revealed that mRNA levels of MMP2 and TIMP2 were decreased, while the MMP2/TIMP2 mRNA ratio was increased, which might facilitate the ECM degradation. Because of the pivotal role of TGF-β/Smad pathway in palatogenesis we therefore checked the effect of RA on TGF-β/Smad signaling. The results indicated RA treatment increased Smad7 expression and decreased the levels of TGF-β1, TGF-β3, TGF-β type II receptor (TβRII) and phosphorylated Smad2 and Smad3. Activation of the Smad pathways by either exogenous TGF-β3 or recombinant adenoviruses for Smad3 attenuated RA-induced inhibition of cell proliferation and ECM components and rescued the RA-altered MMP2/TIMP2 mRNA ratio. In conclusion, these findings suggested that RA overexposure inhibited cell proliferation and disrupted the ECM network through down-regulation of TGF-β/Smad pathway.