Aberrant methylation of secreted protein acidic and rich in cysteine gene and its significance in gastric cancer

BACKGROUND Aberrant methylation in DNA regulatory regions could downregulate tumor suppressor genes without changing the sequences.However,our knowledge of secreted protein acidic and rich in cysteine(SPARC)and its aberrant methylation in gastric cancer(GC)is still inadequate.In the present research,we performed fundamental research to clarify the precise function of methylation on SPARC and its significance in GC.AIM To investigate promoter methylation and the effects of the SPARC gene in GC cells and tissues and to evaluate its clinical significance.METHODS Plasmids that overexpressed the SPARC gene were transfected into human GC BGC-823 cells;non-transfected cells were used as a control group(NC group).Quantitative real-time polymerase chain reaction and western blotting(WB)were then used to detect the expression of SPARC.Methylation-specific polymerase chain reaction was executed to analyze the gene promoter methylation status.Cell viability was measured by the cell counting kit-8 assay.The migration and invasion ability of cells were detected by scratch assays and transwell chamber assays,respectively.Cell cycle events and apoptosis were observed with a flow cytometer.RESULTS The expression of SPARC mRNA in GC tissues and cells was significantly lower and showed differing degrees of hypermethylation,respectively,than that in normal adjacent tissues and control cells.Treatment with 5-Aza-2’-deoxycytidine(5-Aza-Cdr)was able to restore the expression of SPARC and reverse promoter hypermethylation.Overexpression of the SPARC gene significantly inhibited proliferation,migration,and invasion of GC cells,while also causing cell cycle arrest and apoptosis;the NC group exhibited the opposite effects.CONCLUSION This study demonstrated that SPARC could function as a tumor suppressor and might be silenced by promoter hypermethylation.Furthermore,in GC cells,SPARC inhibited migration,invasion,and proliferation,caused cell cycle arrest at the G0/G1 phase,and promoted apoptosis.

Diagnostic and prognostic value of secreted protein acidic and rich in cysteine in the diffuse large B-cell lymphoma

BACKGROUND Secreted protein acidic and rich in cysteine(SPARC)is an extracellular matrixassociated protein.Studies have revealed that SPARC is involved in the cell interaction and function including proliferation,differentiation,and apoptosis.However,the role of SPARC in cancer is controversial,as it was reported as the promoter or suppressor in different cancers.Further,the role of SPARC in lymphoma is unclear.AIM To identify the expression and significance of SPARC in lymphoma,especially in diffuse large B-cell lymphoma(DLBCL).METHODS The expression analysis of SPARC in different cancers was evaluated with Oncomine.The Brune,Eckerle,Piccaluga,Basso,Compagno,Alizadeh,and Rosenwald datasets were included to evaluate the mRNA expression of SPARC in lymphoma.The Cancer Genome Atlas(TCGA)-DLBCL was used to analyze the diagnostic value of SPARC in DLBCL.The Compagno and Brune DLBCL datasets were used for validation.Then,the diagnostic value was evaluated with the receiver operating characteristic(ROC)curve.The Kaplan-Meier plot was conducted with TCGA-DLBCL,and the ROC analysis was performed based on the survival time.Further,the overall survival analysis based on the level of SPARC expression was performed with the GSE4475 and E-TABM-346.The Gene Set Enrichment Analyses(GSEA)was performed to make the underlying mechanism-regulatory networks.RESULTS The pan-cancer analysis of SPARC showed that SPARC was highly expressed in the brain and central nervous system,breast,colon,esophagus,stomach,head and neck,pancreas,and sarcoma,especially in lymphoma.The overexpression of SPARC in lymphoma,especially DLBCL,was confirmed in several datasets.The ROC analysis revealed that SPARC was a valuable diagnostic biomarker.More importantly,compared with DLBCL patients with low SPARC expression,those with higher SPARC expression represented a higher overall survival rate.The ROC analysis showed that SPARC was a favorable prognostic biomarker for DLBCL.Results of the GSEA confirmed that the high expression of SPARC was closely associated with focal adhesion,extracellular matrix receptor interaction,and leukocyte transendothelial migration,which suggested that SPARC may be involved in the regulation of epithelial-mesenchymal transition,KRAS,and myogenesis in DLBCL.CONCLUSION SPARC was highly expressed in DLBCL,and the overexpression of SPARC showed sound diagnostic value.More interestingly,the overexpression of SPARC might be a favorable prognostic biomarker for DLBCL,suggesting that SPARC might be an inducible factor in the development of DLBCL,and inducible SPARC was negative in some oncogenic pathways.All the evidence suggested that inducible SPARC might be a good diagnostic and prognostic biomarker for DLBCL.

Secreted protein acidic and rich in cysteine(SPARC)induces epithelial-mesenchymal transition,enhancing migration and invasion,and is associated with high Gleason score in prostate cancer

Secreted protein acidic and rich in cysteine(SPARC)is a matricellular protein highly expressed in bone tissue that acts as achemoattractant factor promoting the arrival of prostate cancer(PCa)cells to the bone marrow.However,the contribution of SPARCduring the early stages of tumor progression remains unclear.In this study,we show that SPARC is highly expressed in PCa tissueswith a higher Gleason score.Through stable knockdown and overexpression of SPARC in PC3 and LNCaP cells,respectively,here wedem on strate that en doge nous SPARC induces the epithelial-mesenchymal tran sition(EMT),decreasing E-cadheri n and cytokeratin18 and increasing N-cadheri n and vime ntin.Moreover,SPARC in duces the expression of EMT regulatory tran scription factors Snailfamily transcriptional repressor 1(Snail),Snail family transcriptional repressor 2(Slug),and zinc finger E-box binding homeobox 1(Zeb1).In addition,SPARC knockdown in PC3 cells decreases migration and invasion in vitro,without modifying cell proliferation.Our results indicate that SPARC might facilitate tumor progression by modifying the cellular phenotype in cancer cells.

血清SPARC及SERPIND1与鼻咽癌患者放疗敏感性及预后的相关性

目的研究鼻咽癌(NPC)患者血清富含半胱氨酸的酸性分泌蛋白(SPARC)、纤维蛋白活化因子抑制蛋白(SERPIND1)表达与放疗敏感性及预后的关系。方法收集2017年1月—2019年1月南京大学医学院附属盐城第一医院肿瘤放疗科诊治NPC患者98例为NPC组,选取同期体检的健康人群60例为健康对照组。酶联免疫吸附试验检测血清SPARC、SERPIND1水平。根据NPC患者放疗反应性将NPC患者分为放疗敏感亚组(n=68)和放疗抵抗亚组(n=30)。比较不同临床病理特征、放疗反应的NPC患者血清SPARC、SERPIND1水平差异。绘制Kaplan-Meier曲线,Log-Rank检验比较不同SPARC、SERPIND1表达患者生存预后的差异。采用Cox回归分析NPC预后的影响因素。结果放疗前NPC组患者血清SPARC、SERPIND1水平高于健康对照组(t=37.535、48.522,P均<0.001)。放疗前放疗抵抗亚组NPC患者血清SPARC、SERPIND1水平明显高于放疗敏感亚组(t/P=14.034/<0.001、7.772/<0.001),放疗后2亚组血清SPARC、SERPIND1水平均降低,且放疗敏感亚组低于放疗抵抗亚组(t/P=22.974/<0.001、18.137/<0.001)。肿瘤TNM分期Ⅲ~Ⅳ期、有淋巴结转移NPC患者放疗前血清SPARC、SERPIND1水平高于TNM分期Ⅰ~Ⅱ期、无淋巴结转移者(t/P=16.539/<0.001、16.799/<0.001、15.756/<0.001、15.015/<0.001)。血清SPARC高表达和低表达患者3年总生存率分别为50.00%(24/48)、92.00%(46/50)。血清SERPIND1高表达和低表达患者3年总生存率分别为53.19%(25/47),88.24%(45/51),血清SPARC、SERPIND1高表达NPC患者3年累积生存率明显低于血清SPARC、SERPIND1低表达患者(Log-rankχ^(2)=21.500、14.790,P均<0.001)。TNM分期Ⅲ~Ⅳ期、淋巴结转移、SPARC高表达、SERPIND1高表达是影响NPC预后的独立危险因素[HR(95%CI)=1.608(1.225~2.112)、1.917(1.319~2.799)、1.839(1.228~2.753)、1.738(1.246~2.426)]。结论NPC患者血清SPARC、SERPIND1水平上调,与NPC患者不良临床病理特征及放疗敏感性有关,是评估NPC患者预后的血清肿瘤标志物。

Shattering the castle walls: Anti-stromal therapy for pancreatic cancer

Despite the availability of potent chemotherapy regimens, such as 5-fluorouracil, folinic acid, irinotecan, and oxaliplatin(FOLFIRINOX) and nab-paclitaxel plus gemcitabine, treatment outcomes in metastatic pancreatic cancer(PC) remain unsatisfactory. The presence of an abundant fibrous stroma in PC is considered a crucial factor for its unfavorable condition. Apparently, stroma acts as a physical barrier to restrict intratumoral cytotoxic drug penetration and creates a hypoxic environment that reduces the efficacy of radiotherapy. In addition, stroma plays a vital supportive role in the development and progression of PC, which has prompted researchers to assess the potential benefits of agents targeting several cellular(e.g., stellate cells) and acellular(e.g., hyaluronan) elements of the stroma. This study aims to briefly review the primary structural properties of PC stroma and its interaction with cancer cells and summarize the current status of antistromal therapies in the management of metastatic PC.

Change of SPARC expression after chemotherapy in gastric cancer

Objective： The expression of tumor biomarkers may change after chemotherapy. However, whether secreted protein acidic and rich in cysteine （SPARC） expression changes after chemotherapy in gastric cancer （GC） is unclear, qqais study investigated the influence of chemotherapy on SPARC expression in GC. Methods： Immunohistochemistry was used to analyze SPARC expression in 132 GC cases （including 54 cases with preoperative chemotherapy and 78 cases without preoperative chemotherapy）. SPARC expression of postoperative specimens with and without preoperative chemotherapy was assessed to analyze the influence of chemotherapy on SPARC expression. Results： SPARC was highly expressed in GC compared with the desmoplastic stroma surrounding tumor cells and noncancerous tissues. High SPAKC expression was correlated with invasion depth, lymph node, and TNM stage. After chemotherapy, a lower proportion of high SPARC expression was observed in patients with preoperative chemotherapy than in the controls. For 54 patients with preoperative chemotherapy; gross type, histology, depth of invasion, lymph node, TNM stage, and SPARC expression were related to overall survival. Further multivariate analysis showed that lymph node, histology, and SPARC expression after chemotherapy were independent prognostic factors. Conclusiou： SPARC expression may change after chemotherapy in GC. SPARC expression should be reassessed for patients with GC after chemotherapy.

Chronic spinal cord compression associated with intervertebral disc degeneration in SPARC-null mice

Chronic spinal cord compression(CSCC)is induced by disc herniation and other reasons,leading to movement and sensation dysfunction,with a serious impact on quality of life.Spontaneous disc herniation rarely occurs in rodents,and therefore establishing a chronic spinal cord compression(CSCC)animal model is of crucial importance to explore the pathogenesis and treatment of CSCC.The absence of secreted protein,acidic,and rich in cysteine(SPARC)leads to spontaneous intervertebral disc degeneration in mice,which resembles human disc degeneration.In this study,we evaluated whether SPARC-null mice may serve as an animal model for CSCC.We performed rod rotation test,pain threshold test,gait analysis,and Basso Mouse Scale score.Our results showed that the motor function of SPARC-null mice was weakened,and magnetic resonance images revealed compression at different spinal cord levels,particularly in the lumbar segments.Immunofluorescence staining and western blot assay showed that the absence of SPARC induced apoptosis of neurons and oligodendrocytes,activation of microglia/macrophages with M1/M2 phenotype and astrocytes with A1/A2 phenotype;it also activated the expression of the NOD-like receptor protein 3 inflammasome and inhibited brain-derived neurotrophic factor/tyrosine kinase B signaling pathway.Notably,these findings are characteristics of CSCC.Therefore,we propose that SPARC-null mice may be an animal model for studying CSCC caused by disc herniation.

微小核糖核酸-451a在人参养荣汤治疗鼻咽癌放射性黏膜损伤中的机制研究

目的:通过检测微小核糖核酸-451a(miR-451a)和富含半胱氨酸的分泌性酸性蛋白(SPARC)mRNA的表达,推断人参养荣汤治疗鼻咽癌(NPC)放射性黏膜损伤的疗效及作用机制。方法:选择2022年3月—2023年5月收治的鼻咽癌放射性口腔黏膜损伤患者30例作为观察组,选择同期健康者30例作为对照组。采用辨证论治拟人参养荣汤加减治疗,比较观察组治疗前后患者中医症候积分量表和口干程度、口咽疼痛程度、黏膜损伤程度。检测治疗前后患者血清miR-451a和SPARC mRNA表达水平。结果:人参养荣汤可以有效降低患者主症和次症严重程度、Ⅲ级和Ⅳ级口腔黏膜损伤程度、口咽疼痛程度以及口干程度,使患者血清中miR-451a表达下降,促进SPARC mRNA蛋白翻译增强(P<0.05)。治疗前后,miR-451a与中医症候积分均呈正相关(P<0.05)。结论:人参养荣汤对鼻咽癌放射性黏膜损伤具有一定的临床疗效,可降低miR-451a表达水平,升高SPARC mRNA表达水平;miR-451a抑制了SPARC mRNA的翻译,可为将来的中西医结合治疗提供理论依据。

综合疗法对强直性脊柱炎伴骨质疏松患者血清富含半胱氨酸的酸性蛋白酶的影响

目的观察综合疗法对强直性脊柱炎(ankylosing spondylitis,AS)伴骨质疏松患者血清富含半胱氨酸的酸性蛋白酶(serum secreted protein acidic and rich in cysteine,SPARC)水平的影响,探讨SPARC在AS伴骨质疏松发生过程中可能的作用机制。方法 48例AS伴骨质疏松患者(AS组)采用推拿、静脉滴注鹿瓜多肽注射液及口服补肾祛寒治尪汤治疗3个月,并以健康人45名为健康对照组(对照组);采用酶联免疫吸附法测定AS组治疗前后及对照组的血清SPARC水平,股骨颈骨密度(bone mineral density of femoral neck,FN BMD)、腰2-腰4骨密度(bone mineral density of 2-4 lumbar spine,L2-4BMD)、骨碱性磷酸酶(bone specific alkaline phosphatase,BSAP)、肿瘤坏死因子α(TNF-α)、转化生长因子β1(TGF-β1)水平。同时检测AS组治疗前后Bath AS疾病活动指数(Bath AS disease activity index,BASDAI)及Bath AS功能指数(Bath AS functional index,BASFI),并分析上述指标与血清SPARC水平间的相互关系。结果 AS组血清SPARC水平明显低于对照组(μg/L,175.30±72.04vs190.52±86.13,P<0.01)。AS组血清SPARC水平与TNF-α呈负相关(r=-0.261,P<0.01),与L2-4BMD、TGF-β1、BSAP呈正相关(r=0.437,0.256,0.385,P<0.05,P<0.01);L2-4BMD和BSAP是影响AS组血清SPARC水平的独立相关因素。AS组经综合治疗后TNF-α、BAS-DAI、BASFI明显降低,TGF-β1、BSAP、L2-4BMD和FNBMD明显升高(P<0.05,P<0.01),血清SPARC水平也显著升高[(188.32±87.50)μg/L,P<0.05]。结论综合疗法能有效改善AS伴骨质疏松患者骨代谢水平、临床症状和关节活动功能,同时升高其血清SPARC水平。

食管鳞癌组织中SPARC蛋白表达的临床意义

目的:探讨基质蛋白SPARC在食管鳞癌的增殖、侵润和转移中的作用。方法:应用免疫组化技术研究SPARC在食管鳞癌组织和其相邻的正常粘膜组织的表达差异,同时对蛋白表达进行定位。结果:36例食管鳞癌手术标本中30例SPARC蛋白表达阳性,正常食管上皮组织表达阴性(P<0.01)。SPARC蛋白在不同分化程度的食管鳞癌组织中的表达阳性率基本相同(P>0.05)。有淋巴结转移的食管鳞癌组织与无淋巴结转移癌组织的表达间有显著差异(P<0.05)。4例癌组织细胞核有表达,其余均为细胞浆表达。结论:SPARC和食管癌的发生与发展密切相关。食管癌出现转移时SPARC蛋白表达升高。

KLF4和SPARC在非小细胞肺癌中的表达及其相关性研究

背景与目的已有研究证实KLF4基因(Krüppel-like factor4)和富含半胱氨酸的酸性分泌蛋白(se-creted protein acidic and rich in cysteine,SPARC)与肿瘤的发生发展密切相关。本研究旨在检测KLF4和SPARC蛋白在非小细胞肺癌(non-small cell lung cancer,NSCLC)中的表达,并结合临床病理特征来探讨KLF4和SPARC的临床意义及相关性。方法应用免疫组织化学方法检测89例NSCLC组织及正常肺组织中KLF4和SPARC的表达。结果 KLF4在癌旁正常肺组织阳性表达率为88.8%,NSCLC组织为42.7%(P<0.05);有、无淋巴结转移者的KLF4阳性表达率分别为31.3%和56.1%(P<0.05);KLF4的表达与肿瘤临床分期有关(P<0.05),随着临床分期等级的增加,KLF4表达呈现递减趋势。SPARC在NSCLC组织的阳性表达率为70.8%,癌旁正常肺组织为7.9%(P<0.05);低、高分化癌的SPARC阳性表达率无统计学差异(P>0.05);有、无淋巴结转移者的SPARC阳性表达率分别为81.3%和58.5%(P<0.05);其表达与肿瘤的临床分期相关(P<0.05)。KLF4和SPARC的表达均与患者的性别、年龄和肿瘤大小无关(P>0.05)。SPARC和KLF4在NSCLC中的表达呈负相关(r=-0.245,P<0.05)。结论 KLF4低表达及SPARC的过表达与NSCLC的发生及其生物学行为密切相关,可能作为NSCLC诊断及分期预后的指标。

富含半胱氨酸的酸性分泌糖蛋白在IgA肾病患者血、尿中的含量及肾组织中的表达

目的:测定富含半胱氨酸的酸性分泌糖蛋白(SPARC)在IgA肾病患者血液、尿液中的浓度,并观察其在肾组织中的分布和表达。方法:采用夹心ELISA法对IgA肾病患者和正常人血清和尿液中SPARC、肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)和白细胞介素-6(IL-6)进行定量检测;应用夹心ELISA法检测IL-6处理后的人肾小球系膜细胞(HMC)和人肾小管上皮细胞(HKC)SPARC蛋白的分泌水平;运用免疫组织化学SP法检测SPARC在IgA肾病患者及正常人肾组织中的表达及分布。结果:IgA肾病患者血液及尿液SPARC、TNF-α、IL-1β、IL-6的含量均显著高于正常对照组(P<0.01或P<0.05);IgA肾病患者尿液SPARC浓度显著高于血液浓度(P<0.01)。IL-6(50 pg/ml)分别作用HMC、HKC 96 h后,SPARC蛋白的表达量明显高于对照组(P<0.01),而且HKC组SPARC蛋白的表达量明显高于HMC组(P<0.01)。在正常肾组织中,SPARC在远端小管细胞仅有极微弱表达,在IgA肾病肾组织小管上皮细胞中SPARC蛋白表达较正常肾组织肾小管细胞明显增强。结论:IgA肾病时,增多的炎症因子可刺激肾小管细胞产生和分泌SPARC蛋白增加,引起血清SPARC浓度升高,可能起到一种保护性反馈抑制系膜细胞增殖的作用。

富含半胱氨酸酸性分泌型糖蛋白2.1肽段对体外培养人系膜细胞超微结构及其分泌细胞外基质的影响

目的:观察富含半胱氨酸酸性分泌型糖蛋白(SPARC)2.1肽段对体外培养人肾小球系膜细胞(HMC)超微结构及其分泌细胞外基质的影响。方法:50μg/mlSPARC2.1肽段作用48h、96h后,倒置显微镜下观察HMC形态变化,透射电镜观察其超微结构,以正常培养的HMC作空白对照组。荧光定量RT-PCR法检测空白对照组和50μg/mlSPARC2.1肽段作用96h后HMC分泌细胞外基质[Ⅰ型和Ⅳ型胶原(ColⅠ、ColⅣ)、层粘连蛋白(LN)、纤维连接蛋白(FN)]相关基因mRNA表达的变化;ELISA法比较两组HMC培养上清中细胞外基质(ColⅠ、ColⅣ、LN、FN)的蛋白含量。结果:空白对照组HMC无明显变化;50μg/mlSPARC2.1肽段作用48h电镜可见少数HMC发生凋亡早期改变;96h可见较多细胞发生典型凋亡改变,电镜下可见典型的凋亡小体。与空白对照组相比,SPARC2.1肽段作用96h后,HMC的ColⅠ、ColⅣ、FNmRNA和蛋白含量显著下调(P<0.01,P<0.05),LNmRNA及其蛋白含量无明显变化。结论:SPARC2.1肽段可在体外诱导HMC细胞的凋亡,超微结构可见典型凋亡小体,并抑制其分泌细胞外基质。

SPARC基因在角膜碱烧伤中的表达

目的 动态检测酸性富含胱氨酸分泌型蛋白 (SPA RC)在角膜碱烧伤中的表达 ,为探讨 SPA RC基因在角膜创伤中的作用提供依据。方法 首先建立角膜碱烧伤模型 ,并设角膜物理损伤组为对照组 ,在不同时间段提取各组角膜上皮细胞总RN A。用基因引物进行逆转录 -聚合酶链反应 (RT - PCR )扩增 ,半定量 SPA RC m RN A的表达水平。然后对 PCR扩增结果用限制性内切酶酶切验证。在取角膜上皮之前 ,对受试动物进行裂隙灯检查 ,以判断角膜碱烧伤程度与基因表达的关系。结果 (1)正常角膜上皮细胞可见 SPA RC基因的低表达 ;(2 ) SPA RC在角膜碱烧伤及物理损伤后均见较高水平表达 ,且与正常细胞表达相比较有显著的统计学差异 (P<0 .0 5) ;角膜创伤越严重 ,基因表达水平越高 ;(3 )所检测基因表达结果与显微镜观察角膜水肿、混浊、角膜新生血管等损伤结果呈同步趋势。结论 SPARC在角膜碱烧伤和创伤过程中具有高水平表达。是角膜创伤修复过程中的重要因素。

miR-148b-3p调控瘢痕疙瘩来源的成纤维细胞增殖的机制研究

目的分析miR-148b-3p对瘢痕疙瘩来源的成纤维细胞增殖的影响。方法通过Real-time PCR分析人瘢痕疙瘩来源成纤维细胞(HKF)和正常人成纤维细胞(NFs)中miR-148b-3p和SPARC的表达水平。通过Western blot检测细胞中富含半胱氨酸的酸性分泌蛋白(SPARC)蛋白表达水平。利用细胞计数试剂盒8(CCK-8)法和平板克隆形成分析miR-148b-3p和SPARC对HKF增殖的影响。使用在线分析软件预测miR-148b-3p的靶基因,随后构建荧光素酶报告基因质粒,通过荧光素酶报告基因法分析miR-148b-3p与靶基因的靶向结合位点。结果miR-148b-3p在HKF中低表达,SPARC在HKF中高表达。在HKF细胞中转染miR-148b-3p能够下调SPARC的表达,并抑制细胞增殖。在线分析软件预测miR-148b-3p能够靶向结合SPARC的3′-UTR;双荧光素酶报告基因的结果进一步证实miR-148b-3p能够靶向作用于SPARC的3′-UTR。在转染miR-148b-3p的HKF中再转染SPARC真核表达质粒,能够抵消miR-148b-3p的作用,恢复细胞增殖能力。结论miR-148b-3p通过靶向作用于SPARC的3′-UTR,抑制其表达,抑制HKF增殖。

SPARC在db/db小鼠肾脏组织中高表达

目的检测db/db鼠肾脏组织中的富含半胱氨酸的酸性分泌蛋白(SPARC)的表达情况。方法 RT-PCR、Western blot及免疫荧光方法检测db/db鼠肾脏组织中的SPARC mRNA及蛋白的表达。结果 SPARC在db/db鼠肾脏组织中呈现高表达。结论 db/db鼠肾脏组织中的SPARC呈现高表达(P<0.05),可能与糖尿病肾病的发生与发展有关。

ob/ob鼠骨骼肌组织中SPARC的表达及临床意义

目的观察富含半胱氨酸的酸性分泌蛋白(secreted protein acidic rich in cysteine,SPARC)在具有肥胖及糖尿病表型的ob/ob鼠骨骼肌组织中的表达情况。方法选择10周龄的ob/ob小鼠(C57BL/6J-Lepob/J)与其同窝野生对照型各6只,取其后肢骨骼肌组织,采用RT-PCR方法检测骨骼肌组织中SPARC基因的表达水平,Western blot方法测定SPARC蛋白的表达水平,并用免疫荧光染色方法对骨骼肌组织进行染色观察。结果 SPARC在ob/ob鼠骨骼肌组织中呈现明显高表达。结论 SPARC可能参与了肥胖及糖尿病的发生。

肝癌细胞中SPARC表达及其与糖酵解作用的相关性

目的探究肝细胞癌中分泌性富含半胱氨酸的酸性蛋白(secreted protien acidic and rich in cysteine,SPARC)表达及其与糖酵解作用的相关调节机制。方法选取肝癌细胞HepG2、Hep3B、Huh7,分别稳定转染SPARC质粒和SPARC siRNA,应用比色法检测2种转染的细胞中糖酵解关键酶己糖激酶(HK)和乳酸脱氢酶-A(LDHA)的活性变化。结果转染SPARC质粒的3种肝癌细胞中HK-Ⅱ、LDHA的活性较对照组明显下降,3种细胞中HK-Ⅱ相对吸光度分别降低至(57.45±5.05)%,(56.1±5.70)%,(49.73±7.06)%;LDHA相对吸光度分别降低至(50.53±8.07)%,(54.38±2.08)%,(42.34±3.44)%;差异均有统计学意义(P<0.05);反之,siRNA抑制SPARC表达的肝癌细胞中,HK-Ⅱ、LDHA活性较对照组明显上调,3种细胞中HK-Ⅱ相对吸光度分别上调至(174.20±8.41)%,(166.69±9.71)%,(152.84±3.39)%;LDHA的相对吸光度分别上调至(176.65±6.85)%;(163.24±6.44)%;(151.25±6.75)%,差异具有统计学意义(P<0.05)。结论肝细胞癌中,SPARC通过负性调控糖酵解作用的关键酶抑制糖酵解。

富含半胱氨酸的酸性分泌蛋白与肥胖及其相关疾病的研究进展

肥胖及肥胖相关疾病(如糖尿病、心血管疾病、肿瘤、骨质疏松等)已成为危胁人类健康的主要问题所在。富含半胱氨酸的酸性分泌蛋白(secreted protein acidic and rich in cysteine,SPARC)主要来源于脂肪组织,并与胰岛素抵抗、糖尿病及糖尿病肾病等有关。文中就SPARC的抗细胞黏附、调节细胞增殖、调节组织分化和胚胎发育的分子生物学特性以及与肥胖和肥胖相关疾病的最新研究进展作一综述。

富含半胱氨酸的酸性分泌糖蛋白在病理性瘢痕中的表达及其意义

目的观察富含半胱氨酸的酸性分泌糖蛋白(Secreted protein,acidic and rich in cysteine,SPARC)在瘢痕疙瘩和增生性瘢痕中的表达规律及其意义。方法瘢痕患者的瘢痕疙瘩和3～12个月增生性瘢痕组织各26例;另取手术剩余的正常成人皮肤组织5例;所有标本用40 g/L甲醛固定,行连续切片,厚4μm,应用链菌素生物素-过氧化物酶标记物免疫组织染色法染色。同时设正常对照(正常皮肤)、阳性对照(胃癌癌变组织)、阴性对照(磷酸盐缓冲液代替一抗)。鼠抗人SPARC单克隆一抗浓度为1:200。结果正常成人皮肤中SPARC表达稀少,局限在真皮-表皮交界的乳头真皮,部分靠近基底膜血管和皮肤附件。SPARC在增生性瘢痕的真皮瘢痕组织、皮肤附件中低表达,且早期增生性瘢痕中表达无明显强于晚期增生性瘢痕(P>0.05)。在真皮中SPARC呈弥散性散在分布(同增生性瘢痕),阳性信号表达较低。增生性瘢痕及瘢痕疙瘩的SPARC较正常皮肤表达无差异(P>0.05)。结论SPARC在3～12个月增生性瘢痕中呈低表达,在瘢痕疙瘩中低表达。