Developing Implantable Scaffolds to Enhance Neural Stem Cell Therapy for Post-Operative Glioblastoma

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Effect of ajoene, a natural antitumor small molecule, on human 20S proteasome activity in vitro and in human leukemic HL60 cells

The pharmacologic properties of ajoene, the major sulfur-containing compound purified from garlic, and its possible role in the prevention and treatment of cancer has received increasing attention. Several studies demonstrated that induction of apoptosis and cell cycle blockade are typical biologic effects observed in tumor cells after proteasome inhibition. The proteasome is responsible for the degradation of a variety of intracellular proteins and plays a key role in the regulation of many cellular processes. The aim of the present work was therefore to explore the effects of ajoene on the proteasome activities. In vitro activities of 20S proteasome purified from human erythrocytes on fluorogenic peptide substrates specific for trypsin-like, chymotrypsin-like and peptidylglutamyl peptide hydrolyzing activities revealed that ajoene inhibited the trypsin-like activity in a dose- and time-dependent manner. Further, the ability of 20S proteasome to degrade the OVA(51-71) peptide, a model proteasomal substrate, was partially but significantly inhibited by ajoene. In addition, when human leukemia cell line HL60 was treated with ajoene, both trypsin- and chymotrypsin-like activities were affected, cells arrested in G2/M phase and total amount of cytosolic proteasome increased. All these data clearly indicate that ajoene may affect proteasome function and activity both in vitro and in the living cell. This is a novel aspect in the biologic profile of this garlic compound giving new insights into the understanding of the molecular mechanisms of its potential antitumor action.     

蛋白酶体抑制剂硼替佐米联合柔红霉素对HL-60细胞的凋亡作用和Survivin mRNA表达的影响

目的：研究蛋白酶体抑制剂硼替佐米（Bor）单用或联合柔红霉素（DNR）对HL-60细胞凋亡和Survivin mRNA表达的影响。方法：将不同浓度Bor,DNR及两药联合组和对照组作用于HL-60细胞,采用MTT法测定细胞增殖活性,RT—PCR检测Survivin mRNA表达。结果：5nmol／L Bor作用24h对HL-60细胞有增殖抑制作用,并诱导其凋亡。随着浓度增加及其作用时间的延长可使细胞凋亡率明显增加,10nmol／LBor与1．0μmol／L DNR联合作用72h细胞凋亡率最高,与同剂量两药单独作用相比差异有显著性（P〈0．01）。RT—PCR检测结果表明：随着药物浓度的增加,Survivin mRNA的表达逐渐下降,10mmol／L Bor与1．0μmol／L DNR联合作用72h Survivin mRNA表达最低。结论：Bor能显著抑制HL-60细胞的增殖并诱导其凋亡,Bor联合DNR对HL-60细胞有协同作用,并能显著下调Survivin基因的表达,这可能是促使HL-60细胞凋亡的机制之一。     

Brain tumour stem cells: possibilities of new therapeutic strategies

Cancers are composed of heterogeneous cell populations, including highly proliferative immature precursors and differentiated cells, which may belong to different lineages. Recent advances in stem cell research have demonstrated the existence of tumour-initiating, cancer stem cells (CSCs) in non-solid and solid tumours. These cells are defined as CSCs because they show functional properties that resemble those of their normal counterpart to a significant extent. This concept applies to CSCs from brain tumours and, particularly, to glioblastoma stem-like cells, which self-renew under clonal conditions and differentiate into neuron- and glia-like cells, and into aberrant cells, with mixed neuronal/astroglia phenotypes. Notably, across serial transplantation into immunodeficient mice, glioblastoma stem-like cells are able to form secondary tumours which are a phenocopy of the human disease. A significant effort is underway to identify both CSC-specific markers and the molecular mechanism that underpin the tumorigenic potential of these cells, for this will have a critical impact on the understanding of the origin of malignant brain tumour and the discovery of new and more specific therapeutic approaches. Lately, the authors have shown that some of the bone morphogenetic proteins can reduce the tumorigenic ability of CSCs in GBMs. This suggests that mechanisms regulating the physiology of normal brain stem cells may be still in place in their cancerous siblings and that this may lead to the development of cures that selectively target the population CSCs found in the patients' tumour mass.     

胶质母细胞瘤病理取材方式-七分法取材

目的规范胶质母细胞瘤（GBM）的病理取材方式,为临床提供更为准确的病理信息。方法我们规范GBM病理取材方式为“七分法取材”,即由术者在术中对GBM瘤块的“中心、前方、后方、内测、外侧、上方、下方”共7个位置进行取材。本研究共纳入了40例经“七分法取材”的GBM患者,我们分别对各个位置取材的肿瘤组织进行原代细胞培养,免疫组化检测7个位置取材组织的IDH1蛋白、MGMT蛋白的表达情况。结果肿瘤中心取材的肿瘤组织100%培养出了肿瘤细胞,细胞呈长梭形、迁移快、增殖较块;T1增强像以外其他位置取材的肿瘤组织原代细胞培养成功率为60%,细胞呈圆钝形、迁移慢、增殖慢,两种细胞在细胞形态、细胞学功能上存在明显差异。IDH1蛋白在7个位置表达情况存在差异的病例为10例,比例为25%,差异具有统计学意义（P=0.001）; MGMT蛋白在7个位置表达存在差异的病例为12例,占比为30%,差异具有统计学意义（P=0.004）。结论7个位置取材的组织中均可培养出肿瘤细胞,并且IDH1及MGMT蛋白的表达也存在差异。中心取材的肿瘤组织虽能准确反映肿瘤的病理学级别,但是考虑到GBM高度异质性故需综合考虑其他位置取材的组织病理及分子病理特征,才能更准确地反应肿瘤的生物学特性。故七分法取材较传统的病理取材对GBM的病理诊断更有指导意义。     

多发性骨髓瘤的过去、现在及未来

多发性骨髓瘤是一种浆细胞系恶性肿瘤，依靠传统的化疗方案不能够治愈。近年来，基于对骨髓瘤生物学、遗传学以及肿瘤发生学的深入研究，开发研制出一些新药，并提出了靶向治疗的新方法，如利用蛋白酶体抑制剂、免疫调节剂等，能够极大的改善病人的预后；另外，新的联合化疗方案的出现，也明显提高了缓解率。这些新的治疗策略为临床工作带来了巨大帮助，本文对治疗多发性骨髓瘤的新看法的最近进展进行了评述。     

蛋白酶体抑制剂对多发性骨髓瘤患者骨髓间充质干细胞迁移能力及其肝细胞生长因子表达的影响

本研究探讨蛋白酶体抑制剂硼替佐米对多发性骨髓瘤(MM)患者骨髓间充质干细胞(MSC)迁移能力及其肝细胞生长因子(HGF)基因表达水平的影响。应用Transwell模型观察MM患者骨髓MSC经2.5 nmol/L硼替佐米处理前后的体外迁移能力,实时定量PCR检测MSC的HGF mRNA的表达水平。结果表明,经2.5 nmol/L的硼替佐米作用48小时后,MSC的迁移能力明显低于对照组,并且HGF mRNA在MSC的表达与对照组相比也明显降低,两者结果均具有统计学意义(p<0.05)。结论:硼替佐米可抑制MM患者骨髓MSC的迁移,同时可下调其趋化相关因子HGF的表达。     

Refractory autoimmune hemolytic anemia in a systemic lupus erythematosus patient: A clinical case report

Warm autoimmune hemolytic anemia (AIHA) is a hematologic disorder with an incidence of 1–3 per 10⁵ individuals/year. Patients with systemic lupus erythematosus (SLE) develop AIHA in 3% of adult cases and 14% of pediatric cases. We report a case of AIHA refractory to multiple lines of treatment in a patient with SLE, who eventually responded to a proteasome inhibitor‐based combination. A patient with systemic lupus erythematous was diagnosed with symptomatic autoimmune hemolytic anemia. The patient was refractory to multiple lines of treatment including prednisone, intravenous immune globulin, methylprednisolone, rituximab, cyclophosphamide, mycophenolate mofetil, and splenectomy. She eventually had a beneficial response to a proteasome inhibitor‐based combination with bortezomib plus mycophenolate mofetil. The treatment of refractory autoimmune hemolytic anemia can be challenging. Patients with AIHA refractory to primary or secondary treatments must resort to receiving novel therapeutic modalities including combinations targeting plasma cell, T‐ and B‐cell proliferation.     

Stem‐Cell Challenges in the Treatment of Alzheimer's Disease: A Long Way from Bench to Bedside

Alzheimer's disease (AD) is the most prevalent type of dementia, and its neuropathology is characterized by deposition of insoluble β‐amyloid peptides, intracellular neurofibrillary tangles, and the loss of diverse neurons. Current pharmacological treatments for AD relieve symptoms without affecting the major pathological characteristics of the disease. Therefore, it is essential to develop new and effective therapies. Stem‐cell types include tissue‐specific stem cells, such as neural stem cells and mesenchymal stem cells, embryonic stem cells derived from blastocysts, and induced pluripotent stem cells (iPSCs) reprogrammed from somatic cells. Recent preclinical evidence suggests that stem cells can be used to treat or model AD. The mechanisms of stem cell based therapies for AD include stem cell mediated neuroprotection and trophic actions, antiamyloidogenesis, beneficial immune modulation, and the replacement of the lost neurons. iPSCs have been recently used to model AD, investigate sporadic and familial AD pathogenesis, and screen for anti‐AD drugs. Although considerable progress has been achieved, a series of challenges must be overcome before stem cell based cell therapies are used clinically for AD patients. This review highlights the recent experimental and preclinical progress of stem‐cell therapies for AD, and discusses the translational challenges of their clinical application.     

白细胞蛋白酶抑制因子在真皮多能干细胞中的表达

目的研究白细胞蛋白酶抑制因子(secretory leukocyte protease inhibitor,SLPI)在真皮多能干细胞中的表达以及同伤口液刺激的关系。方法采用前期建立的技术分离、纯化并扩增真皮多能干细胞,收集伤后1d伤口液,比较伤口液刺激前后真皮多能干细胞和创伤前后大鼠皮肤组织中SLPI mRNA表达的变化。通过Western blot了解伤口液刺激前后真皮多能干细胞中SLPI蛋白表达的变化。结果分离、纯化的真皮多能干细胞形态较为均一,增殖能力强,RT-PCR和Western blot提示,SLPI在真皮多能干细胞中表达,伤口液刺激后表达增强。同时检测到SLPI在创伤后1d大鼠皮肤组织中表达升高。结论SLPI高表达可能是真皮多能干细胞参与创伤修复的重要途径之一。     

干细胞在组织工程及其相关领域的研究进展

干细胞是机体内存在的一类特殊细胞,它们显著的生物学特性是既有自我更新的能力又具有多向分化的潜能。干细胞可分为胚胎干细胞(ESC)和成体干细胞如造血干细胞、骨髓间充质干细胞、神经干细胞、肌肉干细胞、成骨干细胞、内胚层干细胞和视网膜干细胞等。干细胞在组织工程及相关领域应用较广,如最近发现老鼠胚胎干细胞可以向神经细胞分化,可以用来治疗帕金森等神经系统的疾病,并且利用这一分化特性可以作为治疗视网膜退化性疾病的无限的细胞资源。近年来的研究成果给人们显示出干细胞的美好应用前景,关键在于如何确定干细胞是否存在于所有的组织中,如何改进干细胞的分离和培养技术并掌握干细胞向特定谱系定向分化所需的标志物等。尽管如此,使用干细胞的危害性也需提出,尤其是人类的ESC细胞显示出其具有致瘤性,说明未分化的ESC细胞在进行移植前必须完全清除掉。介绍干细胞的概念,就其分类和在组织工程及其相关领域的研究进展。     

Dental stem cells: recent progresses in tissue engineering and regenerative medicine

Since the disclosure of adult mesenchymal stem cells (MSCs), there have been an intense investigation on the characteristics of these cells and their potentialities. Dental stem cells (DSCs) are MSC-like populations with self-renewal capacity and multidifferentiation potential. Currently, there are five main DSCs, dental pulp stem cells (DPSCs), stem cells from exfoliated deciduous teeth (SHED), stem cells from apical papilla (SCAP), periodontal ligament stem cells (PDLSCs) and dental follicle precursor cells (DFPCs). These cells are extremely accessible, prevail during all life and own an amazing multipotency. In the past decade, DPSCs and SHED have been thoroughly studied in regenerative medicine and tissue engineering as autologous stem cells therapies and have shown amazing therapeutic abilities in oro-facial, neurologic, corneal, cardiovascular, hepatic, diabetic, renal, muscular dystrophy and auto-immune conditions, in both animal and human models, and most recently some of them in human clinical trials. In this review, we focus the characteristics, the multiple roles of DSCs and its potential translation to clinical settings. These new insights of the apparently regenerative aptitude of these DSCs seems quite promising to investigate these cells abilities in a wide variety of pathologies.

• Key messages

• Dental stem cells (DSCs) have a remarkable self-renewal capacity and multidifferentiation potential;

• DSCs are extremely accessible and prevail during all life;

• DSCs, as stem cells therapies, have shown amazing therapeutic abilities in oro-facial, neurologic, corneal, cardiovascular, hepatic, diabetic, renal, muscular dystrophy and autoimmune conditions;

• DSCs are becoming extremely relevant in tissue engineering and regenerative medicine.

     

Mesenchymal Stem Cell-Based Therapy for Cardiovascular Disease: Progress and Challenges

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An Overview of Current Position on Cell Therapy in Transfusion Science and Medicine: From Fictional Promises to Factual and Perspectives from Red Cell Substitution to Stem Cell Therapy

Stem cell therapy is a relatively novel field of investigation, in which either differentiated cells or stem cells capable of differentiation are transplanted into an individual with the objective of yielding specific cell types in the damaged tissue and consequently restoring its function. The most successful example of cell therapy is hematopoietic stem cell transplantation, leading to regeneration of a patient’s blood cells, now a widely established procedure for many oncologic and non–oncologic diseases. Innovative cell-based therapies are being developed to replace, regenerate or repair injured, absent, or diseased tissues and organs. However, cell therapy bioproducts are based on their inherent biological features such as proliferation, migratory, capability, plasticity, and capacity of self-renewal, posing serious challenges during such bioproduct development. The extraordinary promise of stem cells for future treatments of otherwise intractable diseases has raised great hope and expectations in patients, advocates, physicians, and researchers alike. However, despite thousands of scientific publications and research programs, increased efforts need to be put into the identification of the factors involved, biological mechanisms and materials that affect safety/ efficacy, and into the design of cost-effective methods for the harvesting, expansion, manipulation and purification of the cells.     

Osteogenic differentiation of two distinct subpopulations of human adipose-derived stem cells: an in vitro and in vivo study

The first stem cells considered for the reconstruction of bone were bone marrow mesenchymal stem cells (BMSCs). Subsequently, cells with similar marker expression panel and differentiation potential were found in new sources of cells, such as adipose tissue. This source of stem cells has a promising future in tissue-engineering applications, considering the abundance of this tissue in the human body, the easy harvesting and the high number of stem cells that are available from such a small amount of tissue. The isolation of the adipose stem cells is generally performed by means of enzymatic digestion of the tissues, followed by a natural selection of the stem cells based on their capacity to adhere to the culture flasks, leading to a quite heterogeneous population. This constitutes a major drawback for the use of these cells, since the heterogeneity of the cell culture obtained can compromise their proliferation and differentiation potential. In the present study we have analysed the in vitro and in vivo behaviour of two selected subpopulations with high osteogenic potential. For this purpose, ASCs(CD29+) and ASCs (STRO-1+)subpopulations were isolated and in vitro cultured onto a biodegradable polymeric scaffold, using osteogenic medium, before implantation in a nude mice model. The biodegradable polymeric scaffold used is a fibre-mesh structure based on a blend of starch and polycaprolatone (SPCL) that has been successfully used in several bone tissue-engineering studies. The implanted ASCs-scaffold constructs promoted the formation of new bone tissue in nude mice. However, the results obtained show differences in the behaviour of the two ASCs subpopulations under study, particularly regarding their potential to differentiate into the osteogenic lineage, and allowed the indentification of ASCs (STRO-1+) as the best subpopulation for bone tissue-engineering applications.