Selective central nervous system tropism of primary central nervous system lymphoma

Primary Central nervous system lymphoma (PCNSL) is most frequently a diffuse large B cell lymphoma (DLBCL), which is confined to the Central nervous system (CNS). We performed an experiment in which lymphoma cells from a PCNSL patient were implanted subcutaneously in an athymic mouse. The lymphoma cells were shown to home to the CNS with histologic evaluations of the brain showing multiple large B cells in blood vessels consistent with intravascular large B cell lymphoma (IVL). We did not find any evidence of lymphoma at the site of implantation or other locations. The findings are consistent with highly selective tropism of PCNSLforthe CNS and its vasculature.     

基质细胞衍化因子-1对人内皮祖细胞迁移的影响

目的 探讨基质细胞衍化因子-1对内皮祖细胞迁移的影响.方法 用流式细胞仪、RT-PCR、内皮功能实验鉴定内皮祖细胞,检测其CXCR4受体表达和迁移功能.结果 培养单个核细胞7 d,CD34阳性率为36.3%±23.8%,CD133为19.7%±10.3%,双阳性率为18.6%±10.7%,表达KDR基因,>90%的细胞吸收DiI-ac LDL和FITC-UEA-1.CXCR4表达率为74.8%,对照组、基质细胞衍化因子-1浓度为10、20和50μg/L时,细胞迁移数分别为3.5、7.4、24.9和28.0个.各组浓度的细胞迁移数均显著高于对照组(P<0.01),20μg/L组显著高于10μg/L组、50μg/L组显著高于10μg/L组(P<0.01),50μg/L组显著高于20μg/L组(P<0.05).结论 (1)从外周血途径分离、培养和扩增获得内皮祖细胞,表达CXCR4受体;(2)内皮祖细胞可在基质细胞衍化因子-1的趋化作用下迁移,且与其浓度呈正相关.     

Local cryoglobulin deposition in primary central nervous system lymphoma

Primary central nervous system lymphomas (PCNSLs) represent malignant non-Hodgkin's B-cell lymphomas confined to the central nervous system. Recent years have brought a dramatic increase in the frequency of PCNSL in the immunocompromised and immunocompetent populations. Cryoglobulins are cold-precipitable immunoglobulins associated with a number of infectious, autoimmune, and neoplastic disorders. Although it is known that patients with hematologic malignancies (eg, B-cell lymphomas, chronic lymphocytic leukemia, plasma cell dyscrasias) may have cryoglobulinemias and cryoglobulin deposition in several organs (eg, kidney, liver skin, blood vessels, peripheral nervous system), PCNSL associated with cryoglobulin deposition has not been previously described. This report demonstrates localized cryoglobulin deposition within the tumor bed in an immunocompetent patient with PCNSL.     

中枢神经系统原发性恶性淋巴瘤临床与病理分析

通过对１４例中枢神经系统原发性恶性淋巴瘤临床资料分析及光镜，电镜和免疫组化研究，结果表明：临床上以颅内压增高为主要症状，肿瘤可发生于中枢系统的任何部位。组织学特点，瘤细胞单一，异形，早期常围血管呈袖套样排列，中晚期呈弥漫性分布，无滤波形成。ＬＣＡ，Ｌ２６，ＵＣＨＬ１，ＧＦＡＰ，ＥＭＡ免疫组织化学染色及电镜检查提示肿瘤多数为Ｂ细胞起源。并对其病间，发病机理，诊断和鉴别诊断作了讨论     

Primary central nervous system lymphoma in immunocompetent patients

Primary central nervous system lymphoma has been traditionally described in patients with immunodeficiency syndromes; however, there is an increasing number of immunocompetent patients with this type of tumor that have been reported recently. In this paper we have retrospectively analyzed 22 immunocompetent patients with a confirmed diagnosis of primary lymphoma of the brain. The mean age in this group was 65 years with a similar male/female ratio. The time of evolution of the clinical course was 80.4 days and it was mainly characterized by headache and focal neurological deficit. In four patients multiple lesions were observed, while the remaining presented single lesions mainly located in the periventricular area of the cerebral hemispheres. All patients were initially administered steroids and a stereotactic biopsy was performed. The majority of tumors were histologically classified as diffuse large cells and all of them showed a positive reaction to B-cells antigens on immunohistochemistry. All patients were treated with radiotherapy and in 10 of them, chemotherapy with methotrexate was also indicated. The mean survival rate was II months among patients treated with radiotherapy alone and increased to 36 months when chemotherapy was added.     

原发性中枢神经系统淋巴瘤9例浸润播散方式的临床病理观察

目的 探讨原发性中枢神经系统淋巴瘤(primary central nervous system lymphoma,PCNSL)在脑组织内浸润播散的方式.方法 复习9例PCNSL的临床病理资料,重点观察其在脑组织内浸润播散方式.结果 9例PCNSL中,8例为手术标本,1例为尸解标本,病理类型均为非霍奇金淋巴瘤,8例为弥漫大B细胞淋巴瘤,1例为非特异性外周T细胞淋巴瘤,中位年龄57岁,观察到3种基本浸润和播散方式:(1)沿血管周隙浸润,破坏血管周隙在血管周围浸润,侵入血管壁呈血管炎状改变,使血管腔闭塞.(2)沿神经束间浸润,在大脑灰质层和小脑分子层形成单个或数个细胞与脑表面垂直的条索向脑表面软脑膜下浸润.(3)上述两种方式浸润的瘤细胞最终进入脑皮质浅层和蛛网膜下腔.结论 PCNSL沿血管周隙、血管周围、神经纤维间隙等结构浸润至脑皮层浅层和蛛网膜下隙,并进一步播散.     

原发性中枢神经系统淋巴瘤临床病理及病因学分析

目的 探讨原发性中枢神经系统淋巴瘤(primary central nervous system lymphoma, PCNSL)的临床病理特征、预后指标及病因学.方法 复习39例PCNSL患者的临床资料,同时进行免疫组化、原位杂交检测EBER及PCR检测bcl-2/JH基因重排,并对临床资料、免疫标志物与预后的关系进行分析.结果 34例PCNSL患者的3年生存率为46.4%,5年生存率为27.1%,年龄≥60岁及病变部位深对预后不利(P=0.009和P=0.027),bcl-6阳性表达者的生存率高于阴性表达者(P=0.044),但多因素Cox回归分析显示,进入回归方程的为年龄因素.CD10/bcl-6/MUM-1/CD138分型和治疗方法对预后的判断无显著性差异(P＞0.05).39例患者EBER原位杂交均为阴性,bcl-2/JH基因重排5例阳性(12.8%),其中3例为CD10阳性病例.结论 PCNSL是一种少见的高侵袭性结外非霍奇金淋巴瘤,年龄因素是判断预后的独立性指标,CD10/bcl-6/MUM-1/CD138分型未发现有预后意义,但显示PCNSL的同质性较高,可能是弥漫性大B细胞淋巴瘤的一种亚型.EB病毒感染与PCNSL的病因无相关性.     

Primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is an uncommon extranodal non-Hodgkin lymphoma. Its incidence has increased during the last 3 decades and has been reported in both immunocompromised and immunocompetent patients. Immunocompromised patients are affected at a younger age compared with immunocompetent patients. It presents with raised intracranial pressure and focal neurologic and neuropsychiatric symptoms. The lesions are typically solitary. The majority of the lesions are located in the periventricular area, whereas in a few cases they are located in the supratentorial area. Diffuse large B-cell lymphomas constitute most PCNSLs, whereas T-cell, low-grade, anaplastic, and Hodgkin lymphomas are rarely encountered. The morphology of PCNSL shows a characteristic angiocentric pattern and is positive for B-cell markers by immunohistochemistry. The differential diagnosis of PCNSL includes central nervous system gliomas, metastatic tumors, demyelinating disorders, subacute infarcts, and space-occupying lesions due to an infectious etiology. The understanding of the molecular mechanisms involved in the pathogenesis of PCNSL and the identification of molecular biomarkers have lagged behind that of systemic nodal lymphomas. Primary central nervous system lymphomas are treated with combined radiotherapies and chemotherapies. The prognosis for PCNSL is worse than for other extranodal lymphomas.     

Enhanced wound healing by topical administration of mesenchymal stem cells transfected with stromal cell-derived factor-1

The objective of this study was to investigate the ability of mesenchymal stem cells (MSC) genetically engineered with stromal cell-derived factor-1 (SDF-1) to heal skin wounds. When transfected with SDF-1 plasmid DNA, MSC which were isolated from the bone marrow of rats, secreted SDF-1 for 7 days. In vitro cell migration assay revealed that the SDF-1-engineered MSC (SDF-MSC) enhanced the migration of MSC and dermal fibroblasts to a significantly greater extent than MSC. The SDF-MSC secreted vascular endothelial growth factor, hepatocyte growth factor, and interleukin 6 at a significantly high level. A skin defect model of rats was prepared and MSC and SDF-MSC were applied to the wound to evaluate wound healing in terms of wound size and histological examinations. The wound size decreased significantly faster with SDF-MSC treatment than with MSC and PBS treatments. The length of the neoepithelium and the number of blood vessels newly formed were significantly larger. A cell-tracing experiment with fluorescently labeled cells demonstrated that the percent survival of SDF-MSC in the tissue treated was significantly high compared with that of MSC. It was concluded that SDF-1 genetic engineering is a promising way to promote the wound healing activity of MSC for a skin defect.     

低氧诱导肺动脉内皮细胞间质细胞衍生因子-1的表达及其调控机制

肺血管重塑（PVR）是低氧性肺动脉高压持续且难以逆转的主要原因,其主要病变表现为肺动脉壁细胞增多,但其来源和机制仍不清楚。研究表明骨髓和外周血中存在血管壁细胞的祖细胞,并且参与了PVR的形成。间质细胞衍生因子-1（SDF-1）是特异性介导干细胞归巢至骨髓,介导祖细胞归巢至损伤或缺血组织的关键因子。SDF-1表达在这些部位的血管内皮细胞,而低氧是这些部位的微环境特征,也是诱导SDF-1表达的主要原因。低氧诱导因子-1α（HIF-1α）是特异性介导细胞低氧反应的关键因子,直接调控脐静脉内皮细胞SDF-1基因的表达㈨。我们旨在探讨低氧对肺动脉内皮细胞SDF-1表达的影响及HIF-1α对其表达的调控作用。     

Primary central nervous system B cell lymphoma with features intermediate between diffuse large B cell lymphoma and Burkitt lymphoma

B cell lymphoma with features intermediate between diffuse large B cell lymphoma and Burkitt lymphoma (DLBCL/BL) is a new lymphoma entity which is recognized in the current World Health Organization (WHO) classification (2008). We report a case of a primary central nervous system lymphoma (PCNSL) with findings consistent with DLBCL/BL. It is characterized by a very aggressive clinical course, and a widespread multifocal involvement of the CNS. Our case shows that a DLBCL/BL can manifest in the CNS alone without any systemic involvement.     

软骨损伤后基质细胞衍生因子1的表达

背景：研究表明基质细胞衍生因子1对骨髓间充质干细胞的迁移、聚集有影响。 目的：观察软骨损伤后不同时间损伤修复区组织基质细胞衍生因子1的表达以及与骨髓间充质干细胞迁移的关系。 方法：建立兔软骨损伤模型,分别于建模后2,5,7,10,14,28 d取损伤灶及边缘区组织,检测基质细胞衍生因子1表达和体外细胞迁移实验,观察基质细胞衍生因子1对骨髓间充质干细胞、软骨细胞的迁移影响。 结果与结论：基质细胞衍生因子1的表达呈现出时间变化的趋势,软骨损伤后第7天达到高峰(P < 0.05)。体内移植的骨髓间充质干细胞主要聚集在软骨损伤灶周围,但在封闭CXC趋化因子受体4后,此聚集现象逐渐减弱(P < 0.05)。结果证实,局部组织中基质细胞衍生因子1的表达在软骨损伤早期明显升高,对骨髓间充质干细胞向软骨损伤修复区迁移有重要作用。     

Rapid inactivation of stromal cell-derived factor-1 by cathepsin G associated with lymphocytes

The CXC chemokine stromal cell-derived factor (SDF)-1 is produced constitutively in different tissues. It is the only known ligand for CXCR4, which is widely expressed in leukocytes and in some tissue cells, and acts as coreceptor for X4 HIV strains. Because of the general interest in the mechanisms that regulate the activity of constitutively expressed chemokines, we have studied the inactivation of SDF-1 in cells that bear CXCR4. Here we show that B lymphocytes, NK cells and, to a lesser extent, T lymphocytes inactivate SDF-1 by N-terminal processing. Inactivation is due to cathepsin G which is associated with the membrane of lymphocytes and rapidly cleaves off five N-terminal residues by acting on the Leu(5)-Ser(6) bond yielding SDF-1(6-67). Processing was observed with intact cells, cell membrane preparations and soluble cathepsin G obtained by extraction of the membranes with Triton X-100. Cathepsin G is released by neutrophils and monocytes and binds on the surface of lymphocytes by an apparently saturable process. Analysis of the product obtained, the time course and the sensitivity to inhibitors shows that cathepsin G is the only protease involved. Conversion of SDF-1 to SDF-1(6-67) was complete within minutes to 1-2 h depending on the enzyme source, and was abrogated by inhibitors of serine proteases and chymostatin. Diprotin A, an inhibitor of dipeptidyl peptidase IV, was without effect. Owing to its availability on the surface of SDF-1-responsive cells and its rapid effect, cathepsin G is likely to play a significant role in down-regulating SDF-1 activity.     

Mobilization of mesenchymal stem cells by stromal cell-derived factor-1 released from chitosan/tripolyphosphate/fucoidan nanoparticles

Stromal cell-derived factor 1 (SDF-1) is an important chemokine in stem cell mobilization, and plays a critical role in the biological and physiological functions of mesenchymal stem cells (MSC). However, the use of SDF-1 in tissue regeneration is limited by two drawbacks, which are its short half-life and ready degradation by enzymes. This study investigates the release of SDF-1 from chitosan-based nanoparticles (NP) and evaluates the effect of released SDF-1 on the migration of MSC. Among the prepared chitosan-based NP a chitosan/tripolyphosphate/fucoidan (CS/TPP/F) NP is the most effective carrier for SDF-1 release. CS/TPP/F NP are spherical and effectively encapsulate SDF-1. The CS/TPP/F NP protected SDF-1 against proteolysis and heat treatment and controlled its release for up to 7 days. The concentration of released SDF-1 reached 23 ng ml(-1). According to in vitro experiments on cells the released SDF-1 retained its mitogenic activity, promoted the migration of MSC and enhanced PI3K expression. Biocompatible CS/TPP/F NP may be effective as carriers for the delivery and controlled release of SDF-1 to mobilize stem cells in tissue engineering applications.     

RNA干扰抑制基质细胞衍生因子-1基因的表达

目的通过RNA干扰来抑制骨髓基质细胞衍生因子-1(SDF-1)的表达。方法利用脂质体介导人SDF-1特异性小片段双链RNA(siRNA)的表达质粒转染培养的人骨髓基质细胞,G418筛选阳性克隆。RT-PCR和ELISA法检测培养细胞SDF-1 mRNA和上清液SDF-1蛋白。以转染随机变更siRNA碱基序列的表达质粒和未转染的来源相同的骨髓基质细胞作为对照。结果较未转染和转染随机变更siRNA碱基序列表达质粒的骨髓基质细胞,转染SDF-1特异性siRNA表达质粒的骨髓基质细胞SDF-1 mRNA和SDF-1蛋白明显降低。结论用SDF-1特异性siRNA的表达质粒转染骨髓基质细胞,抑制了SDF-1基因表达。     

Cyclic variability of stromal cell-derived factor-1 and endothelial progenitor cells during the menstrual cycle

The endometrium goes through a unique cycle of physiological angiogenesis during the normal menstrual cycle (MC). We studied whether there is a correlation between endothelial progenitor cells (EPCs) and plasma and endometrial levels of angiogenic growth factors during the MC. Ten healthy, regularly menstruating women provided blood samples and another 16 supplied endometrial biopsies. Blood samples were obtained over a single MC: twice in the proliferative and once in the secretory phase and at ovulation. Endometrial biopsies were provided in the proliferative or in the secretory phase. We assessed plasma levels of vascular endothelial and fibroblast growth factors, granulocyte and granulocyte-macrophage colony-stimulating factors and stromal cell-derived factor-1 (SDF-1) by ELISA; EPCs by a colony-forming unit (CFU) assay; immunostaining for endometrial SDF-1 by computer-assisted software; and endothelial cell (EC) markers by flow cytometry. In the proliferative phase, SDF-1 levels were significantly higher than during the secretory phase. EPC-CFUs correlated negatively to SDF-1 levels. Endometrial SDF-1 expression tended to be higher in the secretory than in the proliferative phase. Furthermore, vascular endothelial growth factor receptors and Tie-2 EPCs showed a cyclic pattern over the MC. Our results point to SDF-1 as a novel mediator of EPC trafficking during the MC.     

Long-term hematopoietic stem cells require stromal cell-derived factor-1 for colonizing bone marrow during ontogeny

The physiological role of SDF-1 on hematopoietic stem cells (HSCs) remains elusive. We show that colonization of bone marrow by HSCs in addition to myeloid cells is severely impaired in SDF-1(-/-) embryos by a long-term repopulation assay. Colonization of spleen by HSCs was also affected, but to a lesser extent. Enforced expression of SDF-1 under the control of vascular-specific Tie-2 regulatory sequences could completely rescue the reduction of HSCs but not myeloid cells in SDF-1(-/-) bone marrow. SDF-1 was detected in the vicinity of the vascular endothelial cells in fetal bone marrow. SDF-1 plays a critical role in colonization of bone marrow by HSCs and myeloid cells during ontogeny, and the mechanisms by which SDF-1 functions are distinct between HSCs and myeloid cells.     

HHV-8/KSHV is not associated with AIDS-related primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a major complication of the late stages of human immunodeficiency virus (HIV) disease. Epstein Barr virus (EBV) infection is the only genetic lesion consistently associated with this neoplasia. Recently, it has been proposed that the pathogenesis of AIDS-related PCNSL (AIDS-PCNSL) may be associated with infection by human herpesvirus-8/Kaposi's sarcoma associated herpesvirus (HHV-8/KSHV), although at present such association remains controversial. In order to conclusively assess the link between HHV-8/KSHV infection and AIDS-PCNSL, we performed a comprehensive study based on multiple molecular assays on cerebral tissues and cerebrospinal fluid (CSF) as well as specific immunologic assays on patients' sera. A well characterized panel of 33 Italian patients with AIDS-PCNSL and 13 controls with other HIV-related brain focal diseases from the same geographical area was analyzed. No signs of HHV-8/KSHV infection were detected in cerebral tissues by single-step PCR. Cerebral tissues of all AIDS-PCNSL scored negative for HHV-8/KSHV DNA sequences also by nested PCR, with the exception of one single patient who was simultaneously affected by Kaposi's sarcoma. All CSF samples analyzed were consistently devoid of HHV-8/KSHV sequences by molecular assays. By serologic assays, detecting both latent and lytic HHV-8/KSHV antigens, a specific immunoreactivity was observed in 16/33 (48%) AIDS-PCNSL and in 6/13 (46%) controls (P = 0.88). A significant correlation with HHV-8/KSHV serum reactivity was seen with a homosexual route of HIV transmission (P = 0.018), but not with the presence of AIDS-PCNSL. The results of our analysis conclusively assess that HHV-8/KSHV infection is not a feature of AIDS-PCNSL.     

MGMT promoter methylation and correlation with protein expression in primary central nervous system lymphoma

The O ⁶-methylguanine-DNA-methyltransferase (MGMT) gene encodes for a DNA repairing enzyme of which silencing by promoter methylation is involved in brain tumorigenesis. MGMT promoter methylation represents a favorable prognostic factor and has been associated with a better response to alkylating agents in glioma and systemic lymphoma. Primary central nervous system lymphoma (PCNSL) is a rare and aggressive extranodal malignant lymphoma. The current standard of care, based on high-dose methotrexate chemotherapy, has improved prognosis but outcome remains poor for a majority of patients. Therapeutic progress in this field is conditioned by limited biological and molecular knowledge about the disease. Temozolomide has recently emerged as an alternative option for PCNSL treatment. We aimed to analyze the MGMT gene methylation status in a series of 24 PCNSLs, to investigate the relationship between methylation status of the gene and immunohistochemical expression of MGMT protein and to evaluate the possible prognostic significance of these biomarkers. Our results confirm that methylation of the MGMT gene and loss of MGMT protein are frequent events in these lymphomas (54 % of our cases) and suggest that they are gender and age related. MGMT methylation showed high correlation with loss of protein expression (concordance correlation coefficient?=??0.49; Fisher exact test: p?MGMT promoter (n?=?4), seems to be associated with a prolonged overall survival (>60 months in three of four patients). The prognostic significance of these molecular markers in PCNSL needs to be further studied in groups of patients treated in a homogeneous way.