异丙酚抑制甲酰基肽受体1减轻脓毒症诱导的小鼠急性肺损伤

为探讨异丙酚在脓毒症诱导的急性肺损伤(acute lung injury,ALI)小鼠模型中的保护作用并通过体外试验观察其对甲酰基肽受体1(formyl peptide receptor 1,FPR1)激动剂诱导的人中性粒细胞活化的抑制作用,将40只小鼠随机分为4组,每组10只:1组为用50μL 10％二甲基亚砜(di...     

生长抑素受体家族与肿瘤

生长抑素及其类似物具有抑制肿瘤增殖或其异常分泌的作用。这些作用是通过肿瘤内高密度表达的生长抑素受体而介导的，并且具有受体亚型的选择性。明确肿瘤中生长抑素受体亚型的分布与表达，以选择特异性的生长抑素类似物，以及提高介导治疗效应具有重要的意义。     

甲酰肽受体2通过p38 MAPK通路参与复发性流产的发生

目的 探讨甲酰肽受体2(FPR2)在复发性流产患者(RSA)绒毛组织中的表达,及其对滋养细胞增殖、迁移和侵袭的影响及作用机制。明确FPR2对滋养细胞功能的影响,分析其在复发性流产中的作用,并对机制进行探讨。方法 收集临床样本(正常30例,RSA30例),利用免疫组织化学染色、Real-time PCR和Western blotting等方法,分析FPR2在RSA患者和正常绒毛组织间的定位和表达差异;应用CRISPR/Cas-9技术,对人绒毛膜滋养细胞系HTR-8/Svneo的FPR2进行敲降并验证;采用CCK-8实验、划痕实验、Transwell实验检测FPR2敲降后滋养细胞增殖、迁移和侵袭能力改变;单独或联合使用p38 MAPK抑制剂SB203580后,采用免疫荧光染色和Western blotting分析FPR2敲降后磷酸化的p38 MAPK(p-p38 MAPK)及p38 MAPK的表达水平;采用CCK-8实验、划痕实验、Transwell实验检测滋养细胞增殖、迁移和侵袭能力改变。结果 复发性流产患者绒毛组织FPR2表达增加;FPR2敲低显著提高了HTR-8/Svneo细胞增殖、...     

尿激酶受体反义核糖核酸抑制肺癌细胞的侵袭转移

目的用反义核糖核酸(RNA)封闭尿激酶受体的表达,抑制人肺癌细胞株95D的侵袭转移能力,验证反义RNA技术在抗肿瘤中的作用.方法将尿激酶受体(uPAR)反义核糖核酸表达质粒转染具有高度侵袭转移能力的人肺癌细胞株95D,利用改良Bovden小室分析转染细胞的体外侵袭能力,并将转染细胞接种裸小鼠以观察其体内转移能力.结果G418筛选后,鉴定出2个表达uPAR反义RNA细胞克隆,uPAR蛋白质水平相应降低.表达uPAR反义RNA的细胞克隆的体外侵袭能力及在裸小鼠体内的肺转移能力较亲本细胞和空载体对照细胞均有显著性降低(P＜0.05).结论抑制尿激酶受体的表达,能够有效抑制肺癌的侵袭转移,反义RNA技术在抗肿瘤治疗中有良好的应用前景.     

脊髓损伤组织匀浆通过甲酰基肽受体2促进神经元突起的生长

文题释义：甲酰基肽受体2：甲酰基肽受体2在吞噬类细胞中的表达和作用已经进行了广泛的研究,主要是促进吞噬细胞的趋化作用。近年来,甲酰基肽受体2在非吞噬类细胞的表达和作用也有相关的报道,如间充质干细胞、神经细胞等,在这些细胞中也能观察到其趋化作用。作者首次研究观察到甲酰基肽受体2能够促进神经元轴突的生长,并被其他实验室研究证实。那么甲酰基肽受体2对脊髓损伤修复是否起作用及其机制,这是一个十分有意义的问题。甲酰基肽受体配体：甲酰基肽受体2配体种类繁多,来源不同,不同的配体与甲酰基肽受体2结合可能导致不同、甚至相反的生物学效应,可能与受体不同的结构域发挥作用有关。然而究竟是哪些结构域在起作用,能否在此水平上来调节受体的功能,并使之产生有利作用,避免有害作用,需要具体问题具体研究。背景：前期研究观察到神经干细胞新分化的神经元表达甲酰基肽受体2,并证实甲酰基肽受体2能促进神经干/祖细胞迁移,诱导向神经元分化。脊髓损伤组织中存在甲酰基肽受体2配体,然而不同的配体与甲酰基肽受体2结合可能导致不同、甚至相反的生物学效应。目的：探讨脊髓损伤产生的配体与甲酰基肽受体2作用后对神经元突起生长的影响。方法：采用酶消化法提取胎鼠大脑皮质神经元;制备SD大鼠脊髓损伤模型,提取损伤脊髓组织匀浆。①实验分组1：观察甲酰基肽受体2激活对神经元突起的影响,分组如下：对照组、甲酰基肽受体2阻断剂组(即添加WRW4)、脊髓匀浆组、脊髓匀浆+WRW4组;②实验分组2：观察甲酰基肽受体2激活后AKT和ERK信号通路阻断对神经元突起的影响,分组如下：对照组、AKT和ERK信号通路阻断剂组(即添加Ly294002+PD98059)、脊髓匀浆组、脊髓匀浆+Ly294002+PD98059组。神经元细胞贴壁24 h后,按上述分组处理7 d,免疫荧光染色共聚焦显微镜观察脊髓匀浆激活甲酰基肽受体2对神经元突起的影响;按上述分组处理30 min,Western blotting检测磷酸化蛋白水平;按上述分组处理24 h,Western blotting检测F-actin水平,观察在甲酰基肽受体2特异性阻断剂WRW4存在的情况下,对MAPK和PI3K/Akt通路中关键蛋白磷酸化的影响。结果与结论：①脊髓损伤组织匀浆液能够使神经元突起长度、初级分枝数、分枝节点数显著增加,这种增加效应大部分被甲酰基肽受体2受体特异性阻断剂WRW4阻断;②脊髓损伤组织匀浆液能够使神经元中ERK1/2和Akt的磷酸化增加,这种效应能够被WRW4阻断;③Akt信号通路阻断剂Ly294002和Erk信号通路阻断剂PD98059能够阻断脊髓匀浆的促进作用;④脊髓损伤组织匀浆能够使F-actin表达量明显增加,这种效应能够被甲酰基肽受体2特异性阻断剂WRW4所阻断;⑤这些实验结果说明,脊髓匀浆液能够通过激活甲酰基肽受体2促进神经元突起生长,这种作用机制可能与ERK1/2和Akt的磷酸化增加相关。ORCID: 0000-0003-1097-1874(张良) 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     

肽类生长因子及其受体与良性前列腺增生研究进展

肽类生长因子是一组强有力的细胞生长调节物质,是多细胞生物进行细胞间信息交流的基础,它们组成复杂的生物信息网络,通过自分泌、旁分泌或内在分泌形式刺激细胞生长,抑制细胞增殖或促进细胞分化与恶变等〔１,２〕。虽然良性前列腺增生（ＢｐＨ）的形成与睾丸是否存在和年龄增长有关,但性激素平衡的失调假说并不能完全解释ＢｐＨ的所有现象,例如：在体外无血清培养时,前列腺上皮细胞的生长并不需要雄激素的参与,而受其它激素或生长因子的刺激〔１〕,而且组织重组研究表明雄激素的作用部位在间质,进而间接地导致邻近上皮细胞增殖与…     

血管内皮生长因子及其受体与肿瘤

血管内皮生长因子 ( VEGF)是一种高度特异和高效的血管生成因子。它与两种特异的酪氨酸激酶受体 flt- 1和 KDR相结合产生作用 ,对于人的某些正常生理功能和某些病理过程如肿瘤的生长及转移起重要作用。以 VEGF及其受体为靶点的抗肿瘤血管形成治疗 ,可以达到预防和治疗肿瘤生长及转移的目的     

趋化因子及其受体的研究新进展

近年来，随着生物信息学和基础信息的发展，人们发现了许多新的趋化细胞因子及其受体，特别是趋化因子受体被发现充当HIV感染的协同受体后，趋化因子领域已经引起了人们的广泛关注。本文探讨了趋化因子及其受体在抗肿瘤治疗，抗HIV感染及抗炎方面的临床应用价值，就趋化因子及其受体领域的研究新进展进行综述。     

降钙素受体家族的受体活性修饰蛋白的研究进展

降钙素基因相关肽家族包括降钙素(calcitonin，CT)、两种降钙素基因相关肽(calcitonin-gene-related peptides,CGRP)、肾上腺髓质素(adrenomedullin，ADM)和胰淀粉样酶(amylin)；它们均与相应的高亲和力受体结合而发挥作用，并且某些受体存在不同的亚型。这些受体包括降钙素受体(Calcitonin receptor，CTR)和降钙素受体样受体(calcitonin receptor-lile receptor，CRLR)。     

House dust mite allergen activates human eosinophils via formyl peptide receptor and formyl peptide receptor-like 1

The objective was to evaluate which receptors house dust mite (HDM) and birch pollen extracts engage to activate human eosinophils. Chemotaxis and degranulation were studied in eosinophils pretreated with pertussis toxin and other antagonists of G protein-coupled receptors, e.g. the formyl peptide receptor (FPR), CC chemokine receptor 3 (CCR3) and leukotriene receptor B4 (LTB(4)R). Inhibition of the FPR as well as desensitization of the receptor rendered eosinophils anergic to activation by the allergens. Blockade of CCR3 or LTB(4)R did not affect eosinophilic reactivity. It was determined by PCR that human eosinophils express the FPR family members FPR and FPR-like 1 (FPRL1). HDM, unlike birch pollen, evoked calcium fluxes in HL-60 cells transfected with FPR or FPRL1. Although both allergens gave rise to calcium transients in neutrophils, which also express FPR and FPRL1, only the HDM response was decreased by the FPR antagonist. Moreover, neutrophils migrated toward HDM but not to birch pollen. Eosinophils pretreated with inhibitors of MAPK p38, ERK1/2 or protein kinase C exhibited diminished responsiveness to the aeroallergens. This study indicates that FPR and FPRL1 mediate the activation of eosinophils by HDM, whereas birch pollen employs other pathways shared with FPR to activate human eosinophils.     

Prognostic factors and characteristics of pancreatic neuroendocrine tumors: single center experience

Purpose: Pancreatic neuroendocrine tumors (PNET) are a rare subgroup of tumors. For PNETs, the predictive factors for survival and prognosis are not well known. The purpose of our study was to evaluate the predictive factors for survival and disease progression in PNETs. Materials and Methods: We retrospectively analyzed 37 patients who were diagnosed with PNET at Severance Hospital between November 2005 and March 2010. Prognostic factors for survival and disease progression were evaluated using the Kaplan-Meier method. Results: The mean age of the patients was 50.0±15.0 years. Eight cases (21.6%) were described as functioning tumors and 29 cases (78.4%) as non-functioning tumors. In univariate analysis of clinical factors, patients with liver metastasis (p=0.002), without resection of primary tumors (p=0.002), or American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) stage III/IV (p=0.002) were more likely to demonstrate shorter overall survival (OS). Patients with bile duct or pancreatic duct invasion (p=0.031), sized-lesions larger than 20 mm (p=0.036), liver metastasis (p=0.020), distant metastasis (p=0.005), lymph node metastasis (p=0.009) or without resection of primary tumors (p=0.020) were more likely to demonstrate shorter progression-free survival (PFS). In multivariate analysis of clinical factors, bile duct or pancreatic duct invasion [p=0.010, hazard ratio (HR)=95.046] and tumor location (non-head of pancreas) (p=0.036, HR=7.381) were confirmed as independent factors for predicting shorter PFS. Conclusion: Patients with liver metastasis or without resection of primary tumors were more likely to demonstrate shorter OS. Patients with bile duct or pancreatic duct invasion or tumors located at body or tail of pancreas were more likely to demonstrate shorter PFS.     

The chemoattractant Trp-Lys-Tyr-Met-Val-D-Met activates eosinophils through the formyl peptide receptor and one of its homologues,formyl peptide receptor-like 1

Whereas prokaryotes use L- and D-isomers of amino acids in their protein synthesis, eukaryotic proteins as a rule incorporate only L-isomers. Hence, D-isomers may constitute danger signals to the innate immune system. A D-methionine-containing peptide, Trp-Lys-Tyr-Met-Val-D-Met-NH(2) (WKYMVm), has been shown to be a stronger activator of neutrophils than f-Met-Leu-Phe. The aim of this study was to compare the responsiveness of eosinophils to WKYMVm with that of neutrophils. The peptide was found to induce chemotaxis and respiratory burst in eosinophils. However, it did not mobilize granule constituents, as evidenced by a lack of eosinophil cationic protein, eosinophil peroxidase, and interleukin-5 in the supernatants of stimulated eosinophils. In contrast, WKYMVm caused the release of complement receptor 3 from secretory vesicles in neutrophils. Different members of the formyl peptide receptor family were preferentially engaged by the peptide in the two classes of granulocytes: the formyl peptide receptor itself in eosinophils and formyl peptide receptor-like 1 in neutrophils.     

67 ku层黏连蛋白受体与肿瘤侵袭和转移

层黏连蛋白是细胞外基质重要的成分之一。67 ku层黏连蛋白受体(67 ku laminin receptor,67 LR)是层黏连蛋白的一个非整合素受体。它是一种多功能蛋白,既参与核糖体的组装、成熟过程,又参与细胞的信号转导,还可作为多种病毒的细胞膜受体。可以和层黏连蛋白相互作用,调节肿瘤的增殖、黏附、微血管形成,加速细胞外基质的降解,促进肿瘤的侵袭转移,其作用机制可能与MAPK信号通路有关。67 LR在多种肿瘤中高表达,还可以作为肿瘤免疫治疗的靶标。     

Inhibition of establishment of primary and micrometastatic tumors by a urokinase plasminogen activator receptor antagonist

Tumor establishment and metastasis are dependent on extracellular matrix proteolysis, tumor cell migration, and angiogenesis. Urokinase plasminogen activator (uPA) and its receptor are essential mediators of these processes. The purpose of this study was to investigate the effect of a recombinant human uPAR antagonist on growth, establishment, and metastasis of tumors derived from human cancer cell lines. A noncatalytic recombinant protein, consisting of amino acids 1-137 of human uPA and the CH2 and CH3 regions of mouse IgG₁ (uPA-IgG), was expressed, purified, and shown to bind specifically to human uPAR and to saturate the surface of human tumor cells which express uPAR. Daily i.p. administration of uPA-IgG to nude mice extended latencies of unstaged tumors derived from Lox melanoma and SW48 colon carcinoma cells by 7.7 and 5.5 days, respectively. uPA-IgG treatment did not affect the growth of Lox or KB tumors staged to 200 mg before antagonist treatment commenced. The effect of uPA-IgG on the establishment of micrometastases was assessed in SCID mice. KB head/neck tumor cells were injected in the tail vein and allowed to seed for 48 h before initiation of daily i.p. injections of uPA-IgG for 24 days. The number of lung colonies ranged between 5 and 30% of vehicle-treated mice in two separate experiments. Furthermore, a single 800 g dose of uPA-IgG administered 1 h prior to tail vein injection of KB cells reduced lung colony formation to just 3.5% of vehicle-treated SCID mice. These data demonstrate that antagonism of uPAR arrested metastasis and inhibited the establishment of primary tumors and micrometastases. Thus, small molecule uPAR antagonists may serve as useful adjuvant agents in combination with existing cancer chemotherapy. © Rapid Science 1998     

Characterization of the rat neutrophil formyl peptide chemotaxis receptor.

Numerous synthetic N-formylated peptides, believed to be the analogs of the naturally occurring initiating signal peptides produced by bacteria, are potent chemotactic agents for phagocytic cells in several species. The authors have characterized the receptor with moderately high affinity for the chemotactic peptide f-Met-Leu-[3H]Phe on the rat peritoneal neutrophils. When neutrophils are incubated with f-Met-Leu-[3H]Phe at 24 C, the binding is saturable and reversible. The receptor on the inflammatory rat neutrophils has an equilibrium dissociation constant (KD) of 3.4 x 10(-8) M at 24 C, and there are approximately 65,000 sites per cell. In addition, the potency of several of these chemotactic peptides in inducing lysosomal enzyme secretion and superoxide production correlated well with their ability to compete with f-Met-Leu-[3H]Phe for receptor binding. Structure activity studies further demonstrate that the fine specificity of the formyl peptide receptor has been conserved across species lines.     

Low density lipoproteins and Lovastatin modulate the organ-specific transendothelial migration of primary and metastatic human colon adenocarcinoma cell lines in vitro

Tumor cell arrest and tumor migration are two of the critical steps in the metastatic cascade. We hypothesized that these steps may be facilitated by the low density lipoprotein (LDL)-induced activation of microvessel endothelial cells (MVEC). The purpose of our study was to investigate the biological effects of an LDL-enriched milieu and the effects of the anticholesterol drug Lovastatin on metastatic behavior. The SW480 and SW620 are primary and metastatic human colonic adenocarcinoma cell lines derived from the same patient. We investigated the effect of LDL on adhesion and migration of the two tumor cell lines across human brain, lung, liver and dermal endothelial monolayers. Adhesion and migration assays were done before and after pretreat-ment of the MVEC or tumor cells with LDL (100 mg/ml) for 24 h. Although metastatic SW620 cells were more adherent to MVEC compared with primary SW480 cells, LDL pretreatment of SW480 and SW620 cells did not affect tumor cell adhesion to MVEC. In contrast, tumor cell migration was significantly increased across endothelial monolayers when MVEC were pretreated with LDL. Transendothelial cell migration was not sig-nificantly affected by pretreatment of the tumor cells with LDL. Lovastatin is an inhibitor of HMG-CoA reduc-tase, the rate-limiting enzyme in cholesterol biosynthesis. It has been shown to have anti-tumor activity in vitro. We investigated the effect of Lovastatin on tumor cell kinetics and tumor cell migration across MVEC. Growth curves and migration assays were done before and after pretreatment of the tumor cells with Lovastatin (30 mg/ml). Migration assays were also done after treatment of unstimulated or LDL-stimulated MVEC (100 mg/ml) for 24 h with Lovastatin. Lovastatin inhibited the in vitro growth of the metastatic SW620 cell line to a greater extent than the invasive SW480E cell line. On the other hand, pretreatment of tumor cells with Lovastatin (30 mg/ml) did not suppress transendothelial tumor cell migration of tumor cells. Finally, Lovastatin given to mice effectively suppressed the number of MCA-26 tumor colonies in the liver of Balb/c mice com-pared with untreated mice. ©Lippincott Williams & Wilkins     

Expression of matrix metalloproteinases and their inhibitors in human brain tumors

Sixty human brain tumors, classified according to the New World Health Organization (WHO) classification including, grade I schwannomas, meningiomas and pilocytic astrocytomas, grade II astrocytomas, grade III anaplastic astrocytomas, grade IV glioblastomas, grade III anaplastic oligodendrogliomas and grade IV glioblastomas and lung and melanoma metastases were analyzed for the expression of three matrix metalloproteinases (MMPs), two tissue inhibitors of MMPs (TIMPs) and for MMP activity. Some correlation was found between MMP expression and the degree of malignancy. Western blotting analysis revealed a more uniform pattern of distribution of MMP-2 (gelatinase A) than of MMP-9 (gelatinase B) and MMP-12 (metalloelastase) among tumors. MMP-9 levels were found to be significantly higher in grade III anaplastic astrocytomas and anaplastic oligodendrogliomas than those in grade I schwannomas and meningiomas. Anaplastic astrocytomas and Grade IV glioblastomas expressed significantly higher levels MMP-12 than grade I meningiomas. All sixty tumors showed a similar pattern of activity in zymography, proMMP-9 being the major species detected. Interestingly, TIMP-1 and TIMP-2 expression levels were especially low in tumors of grade II and grade III but significantly higher in tumors of grade I, particularly in schwannomas. Taken together, these data suggest that: 1) a balance between MMPs and TIMPs has an important role to play in human brain tumors; 2) TIMP expression may be valuable markers for tumor malignancy. This revised version was published online in July 2006 with corrections to the Cover Date.     

C5a and formyl peptide receptor regulation on human monocytes.

Regulation of C5a and formyl-methionine-leucine-phenylalanine-lysine (fMLPL) receptors on human monocytes has been studied using fluorescein-conjugated derivatives and flow cytometry. Monocytes have receptors for each of these ligands, as evidenced by their ability to bind specifically biologically active fluorescein derivatives of these ligands. Quenching experiments showed that bound fluoresceinated C5a and fMLPL are rapidly internalized at 37 degrees C. Once internalized, monocytes are able to reexpress these receptors, returning to control levels within approximately 90 min. This contrasts with rate differences seen in polymorphonuclear neutrophils (PMNs), where fMLPL receptors return more rapidly (approximately 30 min) than do C5a receptors (approximately 100 min). Monensin inhibited the reexpression of C5a but not fMLPL receptors, suggesting that a receptor recycling process is necessary to replenish C5a receptors on the monocyte surface. Similar although less efficient inhibition of C5a receptor reexpression was observed with NH4Cl treatment. Reexpression of both C5a and fMLPL receptors was independent of extracellular Ca2+. Treatment with various agents known to stimulate monocytes and PMNs increased the expression of fMLPL receptors in both cell types but either had no effect on or reduced the level of C5a receptor expression. This would indicate that monocytes, like PMNs, have intracellular pools of preformed fMLPL receptors, available for reexpression. These studies show that, like PMNs, monocytes modulate C5a and fMLPL receptors through different mechanisms. Furthermore, monocytes are capable of reexpressing these receptors following exposure to ligand, a theoretical requirement for chemotaxis.     

Structural and functional characterization of the human formyl peptide receptor ligand-binding region.

The formyl peptide (N-formyl-1-methionyl-1-leucyl-1-phenylalanine [FMLP]) receptor is involved in the activation of neutrophils and their subsequent response to chemotactic N-formylated peptides. Recently, we found that the first extracellular loop closest to the N-terminal end of the FMLP receptor exhibited the strongest ligand binding compared with that shown by other extracellular regions. By constructing amino acid substitutional variants of this domain, we have determined that residues Arg-84 and Lys-85 on this loop play major roles in ligand-binding activity. Furthermore, random rearrangement of the residues of this receptor region demonstrated that the position of these charged amino acids did not affect their involvement in ligand binding, although their presence was essential for this binding to occur. We propose that the portion of the first N-terminal extracellular loop of the FMLP receptor containing residues Arg-84 and Lys-85 contributes significantly to the active site in ligand-receptor binding. We further propose that this binding is not dependent on defined structure but rather that these charged moieties may function as important "contacts" in receptor-ligand interactions.