Stromal cell-derived factor-1α regulates chondrogenic differentiation via activation of the Wnt/β-catenin pathway in mesenchymal stem cells

BACKGROUND Mesenchymal stem cells(MSCs)have been applied to treat degenerative articular diseases,and stromal cell-derived factor-1α(SDF-1α)may enhance their therapeutic efficacy.However,the regulatory effects of SDF-1αon cartilage differentiation remain largely unknown.Identifying the specific regulatory effects of SDF-1αon MSCs will provide a useful target for the treatment of degenerative articular diseases.AIM To explore the role and mechanism of SDF-1αin cartilage differentiation of MSCs and primary chondrocytes.METHODS The expression level of C-X-C chemokine receptor 4(CXCR4)in MSCs was assessed by immunofluorescence.MSCs treated with SDF-1αwere stained for alkaline phosphatase(ALP)and with Alcian blue to observe differentiation.Western blot analysis was used to examine the expression of SRY-box transcription factor 9,aggrecan,collagen II,runt-related transcription factor 2,collagen X,and matrix metalloproteinase(MMP)13 in untreated MSCs,of aggrecan,collagen II,collagen X,and MMP13 in SDF-1α-treated primary chondrocytes,of glycogen synthase kinase 3β(GSK3β)p-GSK3βandβ-catenin expression in SDF-1α-treated MSCs,and of aggrecan,collagen X,and MMP13 in SDF-1α-treated MSCs in the presence or absence of ICG-001(SDF-1αinhibitor).RESULTS Immunofluorescence showed CXCR4 expression in the membranes of MSCs.ALP stain was intensified in MSCs treated with SDF-1αfor 14 d.The SDF-1αtreatment promoted expression of collagen X and MMP13 during cartilage differentiation,whereas it had no effect on the expression of collagen II or aggrecan nor on the formation of cartilage matrix in MSCs.Further,those SDF-1α-mediated effects on MSCs were validated in primary chondrocytes.SDF-1αpromoted the expression of p-GSK3βandβ-catenin in MSCs.And,finally,inhibition of this pathway by ICG-001(5μmol/L)neutralized the SDF-1α-mediated up-regulation of collagen X and MMP13 expression in MSCs.CONCLUSION SDF-1αmay promote hypertrophic cartilage differentiation in MSCs by activating the Wnt/β-catenin pathway.These findings provide further evidence for the use of MSCs and SDF-1αin the treatment of cartilage degeneration and osteoarthritis.

Stromal cell-derived factor-1α promotes recruitment and differentiation of nucleus pulposus-derived stem cells

BACKGROUND Intervertebral disc(IVD) degeneration is a condition characterized by a reduction in the water and extracellular matrix content of the nucleus pulposus(NP) and is considered as one of the dominating contributing factors to low back pain. Recent evidence suggests that stromal cell-derived factor 1α(SDF-1α) and its receptor CX-C chemokine receptor type 4(CXCR4) direct the migration of stem cells associated with injury repair in different musculoskeletal tissues.AIM To investigate the effects of SDF-1α on recruitment and chondrogenic differentiation of nucleus pulposus-derived stem cells(NPSCs).METHODS We performed real-time RT-PCR and enzyme-linked immunosorbent assay to examine the expression of SDF-1α in nucleus pulposus cells after treatment with pro-inflammatory cytokines in vitro. An animal model of IVD degeneration was established using annular fibrosus puncture in rat coccygeal discs. Tissue samples were collected from normal control and degeneration groups.Differences in the expression of SDF-1α between the normal and degenerative IVDs were analyzed by immunohistochemistry. The migration capacity of NPSCs induced by SDF-1α was evaluated using wound healing and transwell migration assays. To determine the effect of SDF-1α on chondrogenic differentiation of NPSCs, we conducted cell micromass culture and examined the expression levels of Sox-9, aggrecan, and collagen II. Moreover, the roles of SDF-1/CXCR4 axis in the migration and chondrogenesis differentiation of NPSCs were analyzed by immunofluorescence, immunoblotting, and real-time RT-PCR.RESULTS SDF-1α was significantly upregulated in the native IVD cells cultured in vitro with pro-inflammatory cytokines, such as interleukin-1β and tumor necrosis factor-α, mimicking the degenerative settings. Immunohistochemical staining showed that the level of SDF-1α was also significantly higher in the degenerative group than in the normal group. SDF-1α enhanced the migration capacity of NPSCs in a dose-dependent manner. In addition, SDF-1α induced chondrogenic differentiation of NPSCs, as evidenced by the increased expression of chondrogenic markers using histological and immunoblotting analyses. Realtime RT-PCR, immunoblotting, and immunofluorescence showed that SDF-1αnot only increased CXCR4 expression but also stimulated translocation of CXCR4 from the cytoplasm to membrane, accompanied by cytoskeletal rearrangement.Furthermore, blocking CXCR4 with AMD3100 effectively suppressed the SDF-1α-induced migration and differentiation capacities of NPSCs.CONCLUSION These findings demonstrate that SDF-1α has the potential to enhance recruitment and chondrogenic differentiation of NPSCs via SDF-1/CXCR4 chemotaxis signals that contribute to IVD regeneration.

Effect of stromal cell-derived factor-1/CXCR4 axis in neural stem cell transplantation for Parkinson’s disease

Previous studies have shown that neural stem cell transplantation has the potential to treat Parkinson’s disease,but its specific mechanism of action is still unclear.Stromal cell-derived factor-1 and its receptor,chemokine receptor 4(CXCR4),are important regulators of cell migration.We speculated that the CXCR4/stromal cell-derived factor 1 axis may be involved in the therapeutic effect of neural stem cell transplantation in the treatment of Parkinson’s disease.A Parkinson’s disease rat model was injected with 6-hydroxydopamine via the right ascending nigrostriatal dopaminergic pathway,and then treated with 5μL of neural stem cell suspension(1.5×104/L)in the right substantia nigra.Rats were intraperitoneally injected once daily for 3 days with 1.25 mL/kg of the CXCR4 antagonist AMD3100 to observe changes after neural stem cell transplantation.Parkinson-like behavior in rats was detected using apomorphine-induced rotation.Immunofluorescence staining was used to determine the immunoreactivity of tyrosine hydroxylase,CXCR4,and stromal cell-derived factor-1 in the brain.Using quantitative real-time polymerase chain reaction,the mRNA expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra were measured.In addition,western blot assays were performed to analyze the protein expression of stromal cell-derived factor-1 and CXCR4.Our results demonstrated that neural stem cell transplantation noticeably reduced apomorphine-induced rotation,increased the mRNA and protein expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra,and enhanced the immunoreactivity of tyrosine hydroxylase,CXCR4,and stromal cell-derived factor-1 in the brain.Injection of AMD3100 inhibited the aforementioned effects.These findings suggest that the stromal cell-derived factor-1/CXCR4 axis may play a significant role in the therapeutic effect of neural stem cell transplantation in a rat model of Parkinson’s disease.This study was approved by the Animal Care and Use Committee of Kunming Medical University,China(approval No.SYXKK2015-0002)on April 1,2014.

Upregulation of stromal cell-derived factor-1 alpha/CXCR4 axis-induced migration of human neural progenitors by tumor necrosis factor-alpha and interleukin-8

BACKGROUND:Studies of several animal models of central nervous system diseases have shown that neural progenitor cells(NPCs) can migrate to injured tissues.Stromal cell-derived factor 1 alpha (SDF-1α),and its primary physiological receptor CXCR4,have been shown to contribute to this process. OBJECTIVE:To investigate migration efficacy of human NPCs toward a SDF-1αgradient,and the regulatory roles of tumor necrosis factor-α(TNF-α) and interleukin-8(IL-8) in SDF-1α/CXCR4 axis-induced migration of NPCs. DESIGN,TIME AND SETTING:An in vitro,randomized,controlled,cellular and molecular biology study was performed at the Laboratory of Department of Cell Biology,Medical College of Soochow University between October 2005 and November 2007. MATERIALS:SDF-1αand mouse anti-human CXCR4 fusion antibody were purchased from R&D Systems,USA.TNF-αwas purchased from Biomyx Technology,USA and IL-8 was kindly provided by the Biotechnology Research Institute of Soochow University. METHODS:NPCs isolated from forebrain tissue of 9 to 10-week-old human fetuses were cultured in vitro.The cells were incubated with 0,20,and 40 ng/mL TNF-α,or 0,20,and 40 ng/mL IL-8,for 48 hours prior to migration assay.For antibody-blocking experiments,cells were further pretreated with 0,20,and 40μg/mL mouse anti-human CXCR4 fusion antibody for 2 hours.Subsequently,the transwell assay and CXCR4 blockade experiments were performed to evaluate migration of human NPCs toward a SDF-1αgradient.Serum-free culture medium without SDF-1αserved as the negative control. MAIN OUTCOME MEASURES:The transwell assay was performed to evaluate migration of human NPCs toward a SDF-1αgradient,which was blocked by fusion antibody against CXCR4.In addition, CXCR4 expression in human NPCs stimulated by TNF-αand IL-8 was measured by flow cytometry. RESULTS:Results from the transwell assay demonstrated that SDF-1αwas a strong chemoattractant for human NPCs(P<0.01),and 20 ng/mL produced the highest levels of migration. Anti-human CXCR4 fusion antibody significantly blocked the chemotactic effect(P<0.05).Flow cytometry results showed that treatment with TNF-αand IL-8 resulted in increased CXCR4 expression and greater chemotaxis efficiency of NPCs towards SDF-1α(P<0.01). CONCLUSION:These results demonstrated that SDF-1αsignificantly attracted NPCs in vitro,and neutralizing anti-CXCR4 antibody could block part of this chemotactic function.TNF-αand IL-8 increased chemotaxis efficiency of NPCs towards the SDF-1αgradient by upregulating CXCR4 expression in NPCs.

Tropism mechanism of stem cells targeting injured brain tissues by stromal cell-derived factor-1

Objective: To explore the role and function of stromal cell-derived factor- 1 (SDF- 1) in stem cells migrating into injured brain area.Methods: Rat-derived nerve stem cells (NSCs) were isolated and cultured routinely. Transwell system was used to observe the migration ability of NSCs into injured nerve cells. Immunocytochemistry was used to explore the expression of chemotactic factor receptor-4 (CXCR-4) in NSCs. In vivo, we applied immunofluorescence technique to observe the migration of NSCs into injured brain area. Immunofluorescence technique and Western blotting were used to test expression level of SDF- 1. After AMD3100 (a special chemical blocker) blocking CXCR-4, the migration ability of NSCs was tested in vivo and in vitro, respectively.Results: NSCs displayed specific tropism for injured nerve cells or traumatic brain area in vivo and in vitro. The expression level of SDF-1 in traumatic brain area increased remarkably and the expression level of CXCR-4 in the NSCs increased simultaneously. After AMD3100 blocking the expression of CXCR-4, the migration ability of NSCs decreased significantly both in vivo and in vitro.Conclusions: SDF-1 may play a key role in stem cells migrating into injured brain area through specially combining with CXCR-4.

Hyperbaric oxygen improves functional recovery of rats after spinal cord injury via activating stromal cell-derived factor-1/CXC chemokine receptor 4 axis and promoting brain-derived neurothrophic factor expression

Background: Spinal cord injury (SCI) is a worldwide medical concern. This study aimed to elucidate the mechanism underlying protective effect of hyperbaric oxygen (HBO) against SCI-induced neurologic defects in rats via exploring the stromal cell-derived factor-1 (SDF-1)/CXC chemokine receptor 4 (CXCR4) axis and expression of brain-derived neurotrophic factor (BDNF). Methods: An acute SCI rat model was established in Sprague-Dawley rats using the Allen method. Sixty rats were divided into four groups (w = 15 in each group): sham-operated, SCI, SCI treated with HBO (SCI + HBO), and SCI treated with both HBO and AMD3100 (an antagonist of CXCR4;SCI + HBO + AMD) groups. The rats were treated with HBO twice a day for 3 days and thereafter once a day after the surgery for up to 28 days. Following the surgery, neurologic assessments were performed with the Basso-Bettie-Bresnahan (BBB) scoring system on postoperative day (POD) 7, 14, 21, and 28. Spinal cord tissues were harvested to assess the expression of SDF-1, CXCR4, and BDNF at mRNA and protein levels, using quantitative real-time polymerase chain reaction, Western blot analysis, and histopathologic analysis. Results: HBO treatment recovered SCI-induced descent of BBB scores on POD 14,(1.25±0.75 vs. 1.03 ±0.66, P< 0.05), 21 (5.27± 0.89 vs. 2.56± 1.24, P< 0.05), and 28 (11.35±0.56 vs. 4.23± 1.20, P<0.05) compared with the SCI group. Significant differences were found in the mRNA levels of SDF-1 (mRNA: day 21, SCI + HBO vs. SCI + HBO + AMD, 2.89± 1.60 vs. 1.56±0.98, P<0.05), CXCR4 (mRNA: day 7, SCI + HBO vs. SCI, 2.99± 1.60 vs. 1.31 ±0.98, P<0.05;day 14, SCI + HBO vs. SCI + HBO + AMD, 4.18± 1.60 vs. 0.80±0.34, P<0.05;day 21, SCI + HBO vs. SCI, 2.10±1.01 vs.1.15±0.03, P<0.05), and BDNF (mRNA: day 7, SCI + HBO vs. SCI, 3.04±0.41 vs. 2.75±0.31, P<0.05;day 14, SCI + HBO vs. SCI, 3.88± 1.59 vs. 1.11 ±0.40, P<0.05), indicating the involvement of SDF-1/CXCR4 axis in the protective effect of HBO. Conclusions: HBO might promote the recovery of neurologic function after SCI in rats via activating the SDF-1/CXCR4 axis and promoting BDNF expression.

Growth and activation of PI-3K/PKB and Akt by stromal cell-derived factor 1a in endometrial carcinoma cells with expression of suppressor endoprotein PTEN

Background Mutation or deletion in the phosphatase and tensin homologue deleted on chromosome ten (PTEN) gene has been identified as an important cause of endometrial carcinoma; stromal cell derived factor-1a (SDF-1a) exerts growth-promoting effects on endometrial cancer cells through activation of the PI-3 kinase /Akt pathway and downstream effectors such as extracellular-responsive kinase (ERK). In this study, a plasmid containing the PTEN gene was transfected into Ishikawa cells to investigate the difference in growth and signal transduction between Ishikawa-PTEN and Ishikawa cells after SDF-1a stimulation, and to study mechanisms of the involvement of PTEN protein in endometrial carcinoma development. Methods Ishikawa cells were transfected with a plasmid (pLXSN-PTEN) containing the PTEN gene and a plasmid (pLXSN-EGFP) with enhanced green fluorescent protein (EGFP). Cells were then screened to obtain Ishikawa-PTEN cells and Ishikawa-neo cells that can both stably express PTEN protein and EGFP. Expression of PTEN protein, phosphorylation levels of AKT and ERK (pAKT and pERK) and growth differences in Ishikawa-PTEN, Ishikawa-neo and Ishikawa cells before and after SDF-1a stimulation were then determined by Western blots and MTT assays. Results Western blot analysis showed that Ishikawa cells produced PTEN after transfection with the PTEN gene. At 15 minutes after SDF-1a stimulation, the pAKT level of Ishikawa-PTEN cells was lower than that of Ishikawa-neo cells and Ishikawa cells. There was no significant difference in pERK levels among the three cell lines. The positive effect of SDF-1a on Ishikawa-PTEN cells growth was markedly less than the effect on Ishikawa-neo and Ishikawa cells. However, in the absence of SDF-1a stimulation (baseline), the pAKT level in Ishikawa-PTEN cells was less than that in Ishikawa cells. There was a significant difference in growth between the Ishikawa-PTEN cells and the Ishikawa-neo cells. Conclusions PTEN gene transfection can regulate the level of pAKT but not pERK in Ishikawa-PTEN cells. PTEN protein may suppress the growth-promoting effect of SDF-1a on endometrial carcinoma by inhibiting the PI-3K/AKT signal transduction pathway.LI Xiao-ping, ZHAO Dan, GAO Min, ZHAO Chao, WANG Jian-liu and WEI

Expression of stromal cell-derived factor-1 in diabetic retinopathy

背景 Neovascularization 能在 proliferative 糖尿病患者 retinopathy (PDR ) 引起视觉损失并且可以被许多因素影响。Stromal 导出房间的 factor-1 (SDF-1 ) 是 angiogenesis 的一个有势力激发器。学习被瞄准与糖尿病的 retinopathy.Methods 在眼睛调查有脉管的 endothelial 生长因素( VEGF )的 SDF-1 和它的关联的表示 SDF-1 和 VEGF 的层次被连接酶的 immunosorbent 试金测量在有 PDR 的 41 个病人的 41 只眼睛和 12 个病人的 12 只眼睛玻璃与自发的有斑点的洞( IMH )。玻璃的液体样品和维管组织的 preretinal 膜在 vitrectomy 被获得。SDF-1 和 VEGF 用 VEGF 的玻璃的集中是的 immunohistochemistry.Results 是局部性的在有 PDR 的眼睛显著地更高((2143.7 湯捩琠牨浯潢浥潢楬? 異浬湯牡 ? 票数瑲湥楳湯 ? 牰汥浩湩牡 ? 硥汰牯瑡潩 ? 湩 ?

Glial cell-derived neurotrophic factor mRNA expression in a rat model of spinal cord injury following bone marrow stromal cell transplantation

BACKGROUND: Several animal experiments utilizing bone marrow stromal cell (BMSC) transplantation for the treatment of spinal cord injury have proposed a hypothesis that BMSC transplantation effects are associated with increased glial cell-derived neurotrophic factor (GDNF) expression. OBJECTIVE: To confirm the effects of BMSC transplantation on GDNF mRNA expression in rats with spinal cord injury by reverse transcription-polymerase chain reaction (RT-PCR). DESIGN, TIME AND SETTING: The present molecular, cell biology experiment was performed at the Key Laboratory of Children's Congenital Malformation, Ministry of Health of China & Department of Developmental Biology, Basic Medical College, China Medical University between March 2006 and May 2007. MATERIALS: Sixty healthy Wistar rats aged 2-4-months and of either gender were included in this study. Spinal cord injury was induced in all rats by hemisection of T9 on the left side. RT-PCR kits were purchased from TaKaRa Company, China. Type 9600 RCR amplifier was provided by PerkinElmer Company, USA. METHODS: Three rats were selected for BMSC culture and subsequent transplantation (after three passages). Of the remaining 57 rats, nine were selected for sham-operation (sham-operated group), where only the T9 spinal cord was exposed without hemisection. A total of 48 rats were randomly and evenly divided into BMSC transplantation and model groups. In the BMSC transplantation group, following spinal cord injury induction, each rat was administered a BMSC suspension through two injection sites selected on the gray and white matter boundary caudally and cephalically, seperately and near to injury site in the spinal cord. The model group received an equal volume of PBS through the identical injection sites. MAIN OUTCOME MEASURES: At 24 and 72 hours, as well as at 7 days, following spinal cord injury, the spinal cord at the T 9 segment was removed. Eight rats were allocated to each time point in the BMSC transplantation and model groups, with three rats allocated to the sham-operated group. GDNF mRNA expression was semiquantitatively analyzed by RT-PCR. RESULTS: The sham-operated group exhibited extremely low GDNF mRNA expression. GDNF mRNA expression significantly increased at 24 hours after spinal cord injury, reached a peak level at 72 hours, and slowly decreased thereafter. However, it remained higher than normal levels at 7 days (P < 0.05). At all time points following spinal cord injury, GDNF mRNA expression was significantly greater in the BMSC transplantation group than in the model group (P < 0.05). CONCLUSION: Transplantation of BMSCs into the injured spinal cord up-regulated GDNF mRNA expression, thereby promoting repair of the injured spinal cord.

Akt-centered amplification loop plays a critical role in vascular endothelial growth factor/stromal cell-derived factor 1-αcross-talk and cardioprotection

然而，背景脉管的 endothelial 生长因素(VEGF ) 在一些织物是 angiogenesis 和幸存因素的主要调停人之一它 cardiomyocytes 上的直接效果糟糕留下 understood.Methods 老鼠新生的室的 myocytes 在 vitro.Akt phosphorylation 是有教养的被西方的弄污测量； stromal 的表示导出房间的因素( SDF-1 ) /CXCR4 轴被即时 PCR 和西方的 blotting.LY294002 评估， AMD3100 被用来防碍发信号 VEGF 和 SDF-1/CXCR4 axis.Cardiac myocytes 生存能力，损害被染色的 trypan 蓝色评估并且喂奶新生的老鼠的脱氢酶( LDH ) release.Results 处理室的 myocytes 与在剂量和 FIk-1 依赖 manner.VEGF 的 Akt 的导致的 phosphorylation 稀释了的 VEGF ， H202 导致了心脏的 myocyte 死亡在通过 PI3K-Akt 的 VEGF 和 SDF-1 之间的串音在 vitro 在 cardiomyocytes 起一个幸存作用。

TATA-box-binding protein-associated factor 15 is a novel biomarker that promotes cell proliferation and migration in gastrointestinal stromal tumor

BACKGROUND Gastrointestinal stromal tumor(GIST)is a common neoplasm with high rates of recurrence and metastasis,and its therapeutic efficacy is still not ideal.There is an unmet need to find new molecular therapeutic targets for GIST.TATA-boxbinding protein-associated factor 15(TAF15)contributes to the progress of various tumors,while the role and molecular mechanism of TAF15 in GIST progression are still unknown.AIM To explore new molecular therapeutic targets for GIST and understand the biological role and underlying mechanisms of TAF15 in GIST progression.METHODS Proteomic analysis was performed to explore the differentially expressed proteins in GIST.Western blotting and immunohistochemical analysis were used to verify the expression level of TAF15 in GIST tissues and cell lines.Cell counting kit-8,colony formation,wound-healing and transwell assay were executed to detect the ability of TAF15 on cell proliferation,migration and invasion.A xenograft mouse model was applied to explore the role of TAF15 in the progression of GIST.Western blotting was used to detect the phosphorylation level and total level of RAF1,MEK and ERK1/2.RESULTS A total of 1669 proteins were identified as differentially expressed proteins with 762 upregulated and 907 downregulated in GIST.TAF15 was selected for the further study because of its important role in cell proliferation and migration.TAF15 was significantly over expressed in GIST tissues and cell lines.Overexpression of TAF15 was associated with larger tumor size and higher risk stage of GIST.TAF15 knockdown significantly inhibited the cell proliferation and migration of GIST in vitro and suppressed tumor growth in vivo.Moreover,the inhibition of TAF15 expression significantly decreased the phosphorylation level of RAF1,MEK and ERK1/2 in GIST cells and xenograft tissues,while the total RAF1,MEK and ERK1/2 had no significant change.CONCLUSION TAF15 is over expressed in GIST tissues and cell lines.Overexpression of TAF15 was associated with a poor prognosis of GIST patients.TAF15 promotes cell proliferation and migration in GIST via the activation of the RAF1/MEK/ERK signaling pathway.Thus,TAF15 is expected to be a novel latent molecular biomarker or therapeutic target of GIST.

Electroacupuncture promotes peripheral nerve regeneration after facial nerve crush injury and upregulates the expression of glial cell-derived neurotrophic factor

The efficacy of electroacupuncture in the treatment of peripheral facial paralysis is known, but the specific mechanism has not been clarified. Glial cell-derived neurotrophic factor(GDNF) has been shown to protect neurons by binding to N-cadherin. Our previous results have shown that electroacupuncture could increase the expression of N-cadherin mRNA in facial neurons and promote facial nerve regeneration. In this study, the potential mechanisms by which electroacupuncture promotes nerve regeneration were elucidated through assessing the effects of electroacupuncture on GDNF and N-cadherin expression in facial motoneurons of rabbits with peripheral facial nerve crush injury. New Zealand rabbits were randomly divided into a normal group(normal control, n = 21), injury group(n = 45) and electroacupuncture group(n = 45). Model rabbits underwent facial nerve crush injury only. Rabbits in the electroacupuncture group received facial nerve injury, and then underwent electroacupuncture at Yifeng(TE17), Jiache(ST6), Sibai(ST2), Dicang(ST4), Yangbai(GB14), Quanliao(SI18), and Hegu(LI4; only acupuncture, no electrical stimulation). The results showed that in behavioral assessments, the total scores of blink reflex, vibrissae movement, and position of apex nasi, were markedly lower in the EA group than those in the injury group. Hematoxylin-eosin staining of the right buccinator muscle of each group showed that the cross-sectional area of buccinator was larger in the electroacupuncture group than in the injury group on days 1, 14 and 21 post-surgery. Toluidine blue staining of the right facial nerve tissue of each group revealed that on day 14 post-surgery, there was less axonal demyelination and fewer inflammatory cells in the electroacupuncture group compared with the injury group. Quantitative real time-polymerase chain reaction showed that compared with the injury group, N-cadherin mRNA levels on days 4, 7, 14 and 21 and GDNF mRNA levels on days 4, 7 and 14 were significantly higher in the electroacupuncture group. Western blot assay displayed that compared with the injury group, the expression of GDNF protein levels on days 7, 14 and 21 were significantly upregulated in the electroacupuncture group. The histology with hematoxylin-eosin staining and Nissl staining of brainstem tissues containing facial neurons in the middle and lower part of the pons exhibited that on day 7 post-surgery, there were significantly fewer apoptotic neurons in the electroacupuncture group than in the injury group. By day 21, there was no significantly difference in the number of neurons between the electroacupuncture and normal groups. Taken together, these results have confirmed that electroacupuncture promotes regeneration of peripheral facial nerve injury in rabbits, inhibits neuronal apoptosis, and reduces peripheral inflammatory response, resulting in the recovery of facial muscle function. This is achieved by up-regulating the expression of GDNF and N-cadherin in central facial neurons.

Leukocyte cell-derived chemotaxin-2 and fibroblast growth factor 21 in alcohol-induced liver cirrhosis

BACKGROUND The importance of early diagnosis of alcoholic liver disease underscores the need to seek better and especially non-invasive diagnostic procedures.Leukocyte cellderived chemotaxin-2(LECT2)has been widely studied to determine its usefulness in monitoring the course of non-alcoholic fatty liver disease but not for alcoholic liver cirrhosis(ALC).AIM To determine the concentration of LECT2 in the blood serum of patients in relation to progressive stages of ALC,its relation to fibroblast growth factor 1(FGF-1)and FGF-21,and to examine the possible wider use of LECT2 in diagnosing ALC.METHODS A retrospective case-control study was conducted with 69 ALC cases and 17 controls with no ALC.Subjects were recruited from the region of Lublin(eastern Poland).Liver cirrhosis was diagnosed based on clinical features,history of heavy alcohol consumption,laboratory tests,and abdominal ultrasonography.The degree of ALC was evaluated according to Pugh-Child criteria(the Pugh-Child score).Blood was drawn and,after centrifugation,serum was collected for analysis.LECT2,FGF-1,and FGF-21 were determined using enzyme-linked immunosorbent assay kits.RESULTS The LECT2 Levels in the control group were 18.99±5.36 ng/mL.In the study groups,they declined with the progression of cirrhosis to 11.06±6.47 ng/mL in one group and to 8.06±5.74 ng/mL in the other(P<0.0001).Multiple comparison tests confirmed the statistically significant differences in LECT2 Levels between the control group and both test groups(P=0.006 and P<0.0001).FGF-21 Levels were 44.27±64.19 pg/mL in the first test group,45.4±51.69 pg/mL in the second(P=0.008),and 13.52±7.51 pg/mL in the control group.The difference between the control group and the second test group was statistically significant(P=0.007).CONCLUSION We suggest that LECT2 may be a non-invasive diagnostic factor for alcoholinduced liver cirrhosis.The usefulness of LECT2 for non-invasive monitoring of alcohol-induced liver cirrhosis was indirectly confirmed by the multiple regression model developed on the basis of our statistical analysis.

Role of Ki-67 as a prognostic factor in gastrointestinal stromal tumors

AIM:To investigate primarily the prognostic value of Ki-67,as well as other parameters,in gastrointestinal stromal tumors(GISTs).METHODS:Ki-67,c-KIT,platelet-derived growth factor receptor-alpha(PDGFRα),smooth muscle actin(SMA),CD34,S100 were stained for immunohistochemistry which was performed on formalin-fixed,paraffinembeded sections on representative block from each case.Proliferation index counted by Ki-67 antibody was calculated as a number of positive nuclear reaction over 100 cells.Immunoreactivity for c-KIT and PDGFRα was evaluated semiquantitatively(weak,intermediate,strong) and for c-KIT type of reactivity was analyzed(cytoplasmic,membrane and "dot-like" staining).Immunoreactivity for SMA,CD34 and S100 were was evaluated as positive or negative antigen expression.Pathologic parameters investigated in this study included tumor size,cell type(pure spindle,pured epitheloid mixed spindle and epitheloid),mitotic count,hemorrhage,necrosis,mucosal ulceration.Clinical data included age,gender,primary tumor location and spread of disease.χ 2 test and Student's t-test were used for comparisons of baseline characteristics.The Cox's proportional hazard model was used for univariable and multivariable analyses.Survival rates were calculated by Kaplan-Meier method and statistical significance was determined by the log-rank test.RESULTS:According to the stage of disease,there were 36 patients with localized disease,29 patients with initially localized disease but with its recurrence in the period of follow up,and finally,35 patients had metastatic disease from the very beginning of disease.Tumor originated most commonly in the stomach(41%),small intestine was the second most common location(36%).The mean size of primary tumors was 6.5 cm.The mean duration of follow-up was 60 mo.Multiple parameters were analyzed for their effect on overall survival,but no one reached statistical significance(P = 0.06).Analysis of time to progression/relapse in initially localized disease(univariate analysis),tumor size,mitotic count,Ki-67 and type of d-KIT distribution(cytoplasmic vs membrane/"dot-like") showed statistically significant correlation.In multivariate analysis in the group of patients with localized disease,there were only 2 parameters that have impact on relapse,Ki-67 and SMA(P < 0.0001 and P < 0.034,respectively).Furthermore,Ki-67 was analyzed in localized diseasevs localized with recurrence and metastatic disease.It was shown that there is a strict difference between these 2 groups of patients(median value was 2.5 for localized disease vs 10.0 for recurrent/metastatic disease,P < 0.0001).It was also shown that the cut-off value which is still statistically significant in terms of relapse on the level of 6%.The curves for survival on that cut-off level are significantly different(P < 0.04,Cox F).CONCLUSION:Ki-67 presents a significant prognostic factor for GIST recurrence which could be of great importance in evaluating malignant potential of disease.

Neuronal differentiation effects of vascular endothelial factor on bone marrow stromal cells

BACKGROUND:Studies have demonstrated that bone marrow stromal cells (BMSCs) undergo neuronal differentiation under certain in vitro conditions.However,very few inducers of BMSC differentiation have been used in clinical application.The effects of vascular endothelial growth factor (VEGF) on in vitro neuronal differentiation of BMSCs remain poorly understood.OBJECTIVE:To investigate the effect of VEGF on neuronal differentiation of BMSCs in vitro,and to determine the best VEGF concentration for experimental induction.DESIGN,TIME AND SETTING:In vitro comparative study was performed at the Central Laboratory and Laboratory of Male Reproductive Medicine,Shenzhen Hospital of Peking University from October 2008 to August 2009.MATERIALS:Recombinant human VEGF165 was purchased from Peprotech Asia,Rehovot,Israel.Neuron-specific enolase (NSE) was purchased from Beijing Biosynthesis Biotechnology,China.METHODS:BMSCs were harvested from adult Sprague Dawley rats.The passaged cells were pre-induced with 10 ng/mL basic fibroblast growth factor for 24 hours,followed by differentiation induction with 0,5,10,and 20 ng/mL VEGF,respectively.MAIN OUTCOME MEASURES:Morphological changes in BMSCs prior to and following VEGF induction.Expression of NSE following induction was determined by immunocytochemistry.RESULTS:Shrunken,round cells,with a strong refraction and thin bipolar or multipolar primary and secondary branches were observed 3 days after induction with 5,10,and 20 ng/mL VEGF.However,these changes were not observed in the control group.At 10 days after induction,the number of NSE-positive cells was greatest in the 10 ng/mL VEGF-treated group (P < 0.05).The number of NSE-positive cells was least in the control group at 3 and 10 days post-induction (P < 0.05).Moreover,the number of NSE-positive cells was greater at 10 days compared with at 3 days after induction (P < 0.05).CONCLUSION:Of the VEGF concentrations tested,10 ng/mL induced the greatest number of neuronal-like cells in vitro from BMSCs.

Emodin and baicalein inhibit pancreatic stromal derived factor-1 expression in rats with acute pancreatitis

BACKGROUND: Stromal derived factor-1 (SDF-1) is an efficacious leukocyte chemoattractant, which can attract lymphocytes and mononuclear cells from bloodstream into the site of inflammation. Emodin, an anthraquinone derivative from Radix et Rhizoma Rhei, and baicalein, a flavone from Scutellaria baicalensis Georgi, both have been reported to possess anti-inflammatory activities. The expression pattern of SDF-1 in experimental acute pancreatitis (AP) and the effect of emodin or baicalein on that are not well defined. The present study aimed to investigate the effects of emodin and baicalein on pancreatic myeloperoxidase (MPO) activity (reflecting leukocyte sequestration) and cytokine production, as well as tissue SDF-1 expression in the setting of AP. METHODS: A rat model of AP was induced by administration of 5% sodium taurocholate through the biliopancreatic duct. The level of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and MPO in the pancreas, and serum amylase were tested by immunohistochemistry, ELISA and chromatometry. The expressions of SDF-1α and SDF-1β were detected by real-time PCR, Western blotting, and immunohistochemistry. RESULT: Combination of emodin and baicalein signifi- cantly reduced pancreatic TNF-α, IL-6 and MPO, and also inhibited pancreatic SDF-1 expression.CONCLUSIONS: The inhibition of SDF-1 expression by emodin and baicalein might contribute, in part at least, to the amelioration of pancreatic inflammation. The present study also shows benefits of simultaneous treatment of AP.

Vascular endothelial growth factor 165b expression in stromal cells and colorectal cancer

AIM:To characterize the implications of vascular endothelial growth factor(VEGF)-A in stromal cells and colorectal cancer and the expression of VEGF-A splice variants.METHODS:VEGF-A expression in tumor and stromal cells from 165 consecutive patients with colorectal cancer was examined by immunohistochemistry.The association between VEGF-A expression status and clinicopathological factors was investigated.Twenty freshfrozen samples were obtained for laser capture microdissection to analyze the splice variants of VEGF-A.RESULTS:VEGF-A was expressed in 53.9% and 42.4% of tumor and stromal cells,respectively.VEGF-A expression in tumor cells(t-VEGF-A) was associated with advanced clinical stage(stage 0,1/9;stage 1,2/16;stage 2,32/55;stage 3,38/66;stage 4,16/19,P < 0.0001).VEGF-A expression in stromal cells(s-VEGF-A) increased in the earlier clinical stage(stage 0,7/9;stage 1,6/16;stage 2,33/55;stage 3,22/66;stage 4,5/19;P = 0.004).Multivariate analyses for risk factors of recurrence showed that only s-VEGF-A expression was an independent risk factor for recurrence(relative risk 0.309,95% confidence interval 0.141-0.676,P = 0.0033).The five-year disease-free survival(DFS) rates of t-VEGF-A-positive and-negative cases were 51.4% and 62.9%,respectively.There was no significant difference in t-VEGF-A expression status.The five-year DFS rates of s-VEGF-A-positive and-negative cases were 73.8% and 39.9%,respectively.s-VEGFA-positive cases had significantly better survival than s-VEGF-A-negative cases(P = 0.0005).Splice variant analysis revealed that t-VEGF-A was mainly composed of VEGF165 and that s-VEGF-A included both VEGF165 and VEGF165b.In cases with no venous invasion(v0),the level of VEGF165b mRNA was significantly higher(v0 204.5 ± 122.7,v1 32.5 ± 36.7,v2 2.1 ± 1.7,P = 0.03).The microvessel density tended to be lower in cases with higher VEGF165b mRNA levels.CONCLUSION:s-VEGF-A appears be a good prognostic factor for colorectal cancer and includes VEGF165 and VEGF165b.

Expression of vascular endothelial growth factor and its receptors VEGFR-1 and 2 in gastrointestinal stromal tumors,leiomyomas and schwannomas

AIM: To investigate the role of vascular endothelial growth factor (VEGF) and its receptors VEGFR-1 and 2 in the growth and differentiation of gastrointestinal stromal tumors (GISTs). METHODS: Thirty-three GISTs, 15 leiomyomas and 6 schwannomas were examined by immunohistochemistry in this study. RESULTS: VEGF protein was expressed in the cytoplasm of tumor cells, and VEGFR-1 and 2 were expressed both in the cytoplasm and on the membrane of all tumors. Immunohistochemical staining revealed that 26 GISTs (78.8%), 9 leiomyomas (60.0%) and 3 schwannomas (50.0%) were positive for VEGF; 24 GISTs (72.7%), 12 leiomyomas (80.0%) and 4 schwannomas (66.7%) were positive for VEGFR-1; 30 GISTs (90.9%), 5 leiomyomas (33.3%) and 4 schwannomas (66.7%) were positive for VEGFR-2. VEGFR-2 expression was statistically different between GISTs and leiomyomas (p < 0.0001). However, there was no correlation between the expression of VEGF pathway componenets and the clinical risk categories. CONCLUSION: Our results suggest that the VEGF pathway may play an important role in the differentiation of GISTs, leiomyomas and schwannomas.

KIT and platelet-derived growth factor receptor α wild-type gastrointestinal stromal tumor associated with neurofibromatosis type 1: Two case reports

BACKGROUND Gastrointestinal stromal tumors(GISTs) associated with neurofibromatosis are uncommon compared to their gastrointestinal counterparts. Patients with neurofibromatosis type 1(NF-1) have an increased risk of developing gastrointestinal tumors, including rare types such as GIST.CASE SUMMARY A 60-year-old male Chinese patient was diagnosed with NF-1 10 years ago and presented with upper abdominal discomfort and black stools. Endoscopic ultrasonography and an enhanced abdominal computed tomography scan revealed a mass located 4 cm from the muscular layer of the descending duodenum. A 59-year-old Chinese woman who was diagnosed with NF-1 25 years ago presented with sudden unconsciousness and black stools. Multiple masses in the duodenum were noted by echogastroscopy and an enhanced abdominal computed tomography scan. Both patients presented with cutaneous neurofibromas. The histologic examination of tumors from both patients revealed spindle cells and low mitotic activity. Immunohistochemically, the tumor cells showed strong positivity for KIT(CD117), DOG-1, CD34, and Dehydrogenase Complex Subunit B, and negativity for SMA, desmin, S-100, and β-catenin. None of the six tumors from two patients had KIT exon 9, 11, 13, or 17 or platelet-derived growth factor receptor α exon 12 or 18 mutation, which is a typical finding for sporadic GISTs. None of the six tumors from the two patients had a BRAFV600 E mutation. The patients were alive and well during the follow-up period(range:0.6-5 yr).CONCLUSION There have been only a few previous reports of GISTs associated with NF-1.Although GISTs associated with NF-1 have morphologic and immunohistochemical similarities with GISTs, the pathogenesis, incidence,genetic background, and prognosis are not completely known. A medical history of NF-1 in a patient who has gastrointestinal bleeding or anemia and an intraabdominal mass with nonspecific computed tomography features may help in diagnosing GIST by virtue of the well-known association of these two entities.Molecular genetic studies of cases indicated that GISTs in NF-1 patients have a different pathogenesis than sporadic GISTs.

STI571 (Glivec) suppresses the expression of vascular endothelial growth factor in the gastrointestinal stromal tumor cell line,GIST-T1

AIM:To estimate whether STI571 inhibits the expressionof vascular endothelial growth factor(VEGF)in thegastrointestinal stromal tumor(GIST)cells.METHODS:We used GIST cell line,GIST-T1.It hasa heterogenic 57-bp deletion in exon 11 to produce amutated c-KIT,which results in constitutive activationof c-KIT.Cells were treated with/without STI571 orstem cell factor(SCF).Transcription and expression ofVEGF were determined by RT-PCR and flow cytometryor Western blotting,respectively.Activated c-KIT wasestimated by immunoprecipitation analysis.Cell viabilitywas determined by MTT assay.RESULTS:Activation of c-KIT was inhibited bySTI571 treatment.VEGF was suppressed at both thetranscriptional and translational levels in a temporal anddose-dependent manner by STI571.SCF upregulatedthe expression of VEGF and it was inhibited by STI571.STI571 also reduced the cell viability of the GIST-T1cells,as determined by MTT assay.CONCLUSION:Activation of c-KIT in the GIST-T1regulated the expression of VEGF and it was inhibited bySTI571.STI571 has antitumor effects on the GIST cellswith respect to not only the inhibition of cell growth,butalso the suppression of VEGF expression.