A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

Long noncoding RNAs HAND2-AS1 ultrasound microbubbles suppress hepatocellular carcinoma progression by regulating the miR-873-5p/tissue inhibitor of matrix metalloproteinase-2 axis

BACKGROUND Increasing data indicated that long noncoding RNAs(lncRNAs)were directly or indirectly involved in the occurrence and development of tumors,including hepatocellular carcinoma(HCC).Recent studies had found that the expression of lncRNA HAND2-AS1 was downregulated in HCC tissues,but its role in HCC progression is unclear.Ultrasound targeted microbubble destruction mediated gene transfection is a new method to overexpress genes.AIM To study the role of ultrasound microbubbles(UTMBs)mediated HAND2-AS1 in the progression of HCC,in order to provide a new reference for the treatment of HCC.METHODS In vitro,we transfected HAND2-AS1 siRNA into HepG2 cells by UTMBs,and detected cell proliferation,apoptosis,invasion and epithelial-mesenchymal transition(EMT)by cell counting kit-8 assay,flow cytometry,Transwell invasion assay and Western blotting,respectively.In addition,we transfected miR-837-5p mimic into UTMBs treated cells and observed the changes of cell behavior.Next,the UTMBs treated HepG2 cells were transfected together with miR-837-5p mimic and tissue inhibitor of matrix metalloproteinase-2(TIMP2)overexpression vector,and we detected cell proliferation,apoptosis,invasion and EMT.In vivo,we established a mouse model of subcutaneous transplantation of HepG2 cells and observed the effect of HAND2-AS1 silencing on tumor formation ability.RESULTS We found that UTMBs carrying HAND2-AS1 restricted cell proliferation,invasion,and EMT,encouraged apoptosis,and HAND2-AS1 silencing eliminated the effect of UTMBs.Additionally,miR-873-5p targets the gene HAND2-AS1,which also targets the 3’UTR of TIMP2.And miR-873-5p mimic counteracted the impact of HAND2-AS1.Further,miR-873-5p mimic solely or in combination with pcDNA-TIMP2 had been transformed into HepG2 cells exposed to UTMBs.We discovered that TIMP2 reversed the effect of miR-873-5p mimic caused by the blocked signalling cascade for matrix metalloproteinase(MMP)2/MMP9.In vivo results showed that HAND2-AS1 silencing significantly inhibited tumor formation in mice.CONCLUSION LncRNA HAND2-AS1 promotes TIMP2 expression by targeting miR-873-5p to inhibit HepG2 cell growth and delay HCC progression.

基质金属蛋白酶-13在多发性骨髓瘤中的作用研究

目的:探讨基质金属蛋白酶-13(MMP-13)在多发性骨髓瘤(MM)疾病发生发展及病情判断、预后评估等方面的作用。方法:收集MM患者57例、正常对照人群45例,采用实时荧光定量PCR检测研究对象MMP-13基因mRNA表达水平,比较MM患者组和正常对照组MMP-13 mRNA表达水平的差异,分析MMP-13与MM骨病及其严重程度、ISS分期、DS分期及治疗效果的关系。结果:MM患者MMP-13mRNA表达水平较正常对照组显著升高(P<0.05);有骨病的MM患者较无骨病的患者MMP-13 mRNA明显升高,且骨病越严重升高越明显(P<0.05);ISS分期及DS分期Ⅰ期与Ⅲ期患者之间MMP-13 mRNA差异也有统计学意义(P<0.05);患者治疗后较治疗前MMP-13明显下降(P<0.05)。结论:MMP-13基因mRNA表达水平与MM发生发展相关,其表达水平在病情判断、预后评估等方面具有一定的指导意义。

慢性肾脏病患者血清CHI3L1、MMP-13表达水平及其病情评估、预后价值

目的探讨慢性肾脏病患者血清几丁质酶3样蛋白1(CHI3L1)、基质金属蛋白酶-13(MMP-13)表达水平及病情评估、预后价值。方法选取2020年3月至2022年8月在江油市人民医院就诊的208例慢性肾脏病患者作为病例组,按照病情严重程度将208例慢性肾脏病患者分为Ⅰ期组21例、Ⅱ期组42例、Ⅲ期组86例、Ⅳ期组38例、Ⅴ期组21例。另选取同期152例体检健康者作为对照组。根据患者预后情况将208例患者分为预后良好组(n=92)及预后不良组(n=116)。收集受试人员一般资料,采用酶联免疫吸附试验检测血清CHI3L1、MMP-13表达水平,Pearson法分析慢性肾脏病患者血清CHI3L1、MMP-13表达水平的相关性,以及二者与肾小球滤过率(GFR)的相关性,采用Cox回归分析影响慢性肾脏病患者预后的因素。结果对照组、病例组年龄、性别等一般资料比较,差异无统计学意义(P>0.05);病例组患者血清中CHI3L1表达水平较对照组显著增加,但MMP-13表达水平显著降低,差异有统计学意义(P<0.05);随着病情分期增加,患者血清CHI3L1表达水平随之增加,MMP-13表达水平随之降低(P<0.05);预后不良组患者血清CHI3L1表达水平较预后良好组显著增加,MMP-13表达水平显著降低(P<0.05);Pearson法分析显示,慢性肾脏病患者血清CHI3L1、MMP-13表达水平呈负相关,CHI3L1表达水平与GFR呈负相关,MMP-13表达水平与GFR呈正相关(P<0.05)。Cox回归分析显示,血清CHI3L1、MMP-13、GFR为慢性肾脏病患者预后不良的独立影响因素(P<0.05)。结论慢性肾脏病患者血清CHI3L1表达水平升高,MMP-13表达水平降低,二者均可用于病情及预后评估。

创面渗出液VEGF、MMP-13、TIMP-1水平对负压封闭引流术联合人工真皮修复难愈性创面效果的预测价值

目的观察难愈性创面患者创面渗出液血管内皮生长因子(vascular endothelial growth factor,VEGF)、基质金属蛋白酶13(matrix metalloproteinase-13,MMP-13)、金属蛋白酶抑制剂1(tissue inhibitor of matrix metalloproteinases-1,TIMP-1)水平,并分析其对负压封闭引流术(vacuum sealing drainage,VSD)联合人工真皮修复治疗难愈性创面临床效果的预测价值。方法选取难愈性创面患者60例纳入难愈组,普通创面患者60例为对照组。所有入选者均检测创面渗出液VEGF、MMP-13、TIMP-1水平,并计算MMP-13/TIMP-1值。采用VSD联合人工真皮修复治疗难愈性创面患者,观察临床效果,并依据临床效果将其分为有效组与无效组,比较有效组与无效组创面渗出液VEGF、MMP-13、TIMP-1水平与MMP-13/TIMP-1值,采用Logistic回归分析上述指标对VSD联合人工真皮修复治疗难愈性创面患者效果的影响,并绘制受试者工作特征曲线(receiver operating characteristic curve,ROC),分析上述指标对VSD联合人工真皮修复治疗难愈性创面患者效果的预测价值。结果难愈组MMP-13水平及MMP-13/TIMP-1值高于对照组,VEGF、TIMP-1水平低于对照组(P<0.05)。60例难愈性创面患者经VSD联合人工真皮修复治疗有效49例(81.67%),无效11例(18.33%)。无效组MMP-13、MMP-13/TIMP-1值高于有效组,VEGF、TIMP-1水平低于有效组(P<0.05)。Logistic回归分析结果显示,MMP-13(95%CI:1.037~1.165)及MMP-13/TIMP-1值(95%CI:1.410~3.458)是难愈性创面患者治疗效果的危险因素,VEGF(95%CI:0.972~0.995)、TIMP-1(95%CI:0.264~0.756)是保护因素(P<0.05)。点二列相关性分析结果显示,VEGF、TIMP-1水平与难愈性创面患者VSD联合人工真皮修复治疗效果呈正相关(r=0.410、0.448,P<0.05),MMP-13水平、MMP-13/TIMP-1值与其治疗效果呈负相关(r=-0.477、0.570,P<0.05)。绘制ROC曲线,结果显示,VEGF(95%CI:0.643~0.908)、MMP-13(95%CI:0.706~0.986)、TIMP-1(95%CI:0.712~0.943)水平及MMP-13/TIMP-1值(95%CI:0.829~0.981)对难愈性创面患者治疗效果具有一定预测价值(AUC=0.776、0.846、0.827、0.905)。结论创面渗出液VEGF、MMP-13、TIMP-1、MMP-13/TIMP-1值能够对VSD联合人工真皮修复治疗难愈性创面效果产生重要影响,临床可通过测定VEGF、MMP-13、TIMP-1、MMP-13/TIMP-1值早期预测治疗效果。

基质金属蛋白酶13在靶向治疗骨关节炎的研究进展

骨关节炎(osteoarthritis,OA)是一类常见的慢性退行性疾病,可导致关节软骨、滑膜、软骨下骨等多组织损伤。目前,该疾病的发病机制尚未完全阐明。研究发现基质金属蛋白酶(matrix metalloproteinase,MMPs)与该疾病的发病过程相关,特别是MMP13,其在机体内的表达水平与OA关系密切。近年来,针对MMP13在该疾病发生发展中的作用,靶向MMP13治疗OA具有诸多进展,选择性MMP13抑制剂较广谱MMPs抑制剂具有选择性强、毒副作用低、效能高等优点,但需要频繁给药以维持药物在体内的有效浓度;将与MMP13 mRNA具有选择性互补的小干扰RNA注射入关节腔可有效降低体内MMP13蛋白产生并抑制多种炎症因子表达,且单次注射可较长时间维持药物效果;利用CRISPR⁃Cas9基因编辑技术靶向消融MMP13基因以减弱软骨细胞外基质蛋白的降解从而治疗OA的方式在动物体内外模型中均具有较好效果,但该技术在人体内长期应用的安全性也引发人们的思考。靶向MMP13治疗OA是医学界及科研领域的重要研究方向,未来结合更前沿的生物医学技术将为探索治疗OA提供新的策略。

补肾痹通方联合骨髓间充质干细胞对损伤软骨细胞的保护机制及SOX9、MMP-13表达的影响

目的:探讨补肾痹通方(BSBT)联合骨髓间充质干细胞(BMSCs)对白介素(IL)-1β诱导的损伤软骨细胞的保护机制及性别决定区Y框蛋白9(SOX9)、基质金属蛋白酶13(MMP-13)表达的影响。方法:使用10 ng/ml的IL-1β建立损伤软骨细胞模型,实验分为对照组、模型组(IL-1β)、中药组(IL-1β+BSBT)、干细胞组(IL-1β+BMSCs)和联合组(IL-1β+BSBT+BMSCs);CCK-8法检测各组软骨细胞增殖情况;RT-qPCR法和Western blot法分别检测软骨细胞内SOX9、MMP-13、Ⅱ型胶原α1重组蛋白(COL2A1)、IL-10的基因和蛋白表达;ELISA检测各组细胞培养上清中肿瘤坏死因子-α(TNF-α)、IL-6、胰岛素样生长因子1(IGF-1)、碱性成纤维细胞生长因子(bFGF)的水平。结果:与模型组比较,各组软骨细胞活性显著增强(P<0.01),软骨细胞中的SOX9、COL2A1、IL-10的基因和蛋白水平显著升高(P<0.01),MMP-13的基因和蛋白水平明显降低(P<0.01),软骨细胞培养上清中TNF-α、IL-6的含量显著降低(P<0.01),IGF-1、bFGF的水平升高(P<0.01),其中联合组变化最明显(P<0.05)。结论:BSBT联合BMSCs可有效保护损伤软骨细胞,其机制可能是通过上调SOX9,下调MMP-13,抑制炎症,改善软骨细胞微环境,促进关节软骨的修复与再生。

Inhibiting MMP13 Attenuates Deep Vein Thrombosis in a Mouse Model by Reducing the Expression of Pdpn

Objective:Matrix metalloproteinase 13(MMP13)is an extracellular matrix protease that affects the progression of atherosclerotic plaques and arterial thrombi by degrading collagens,modifying protein structures and regulating inflammatory responses,but its role in deep vein thrombosis(DVT)has not been determined.The purpose of this study was to investigate the potential effects of MMP13 and MMP13-related genes on the formation of DVT.Methods:We altered the expression level of MMP13 in vivo and conducted a transcriptome study to examine the expression and relationship between MMP13 and MMP13-related genes in a mouse model of DVT.After screening genes possibly related to MMP13 in DVT mice,the expression levels of candidate genes in human umbilical vein endothelial cells(HUVECs)and the venous wall were evaluated.The effect of MMP13 on platelet aggregation in HUVECs was investigated in vitro.Results:Among the differentially expressed genes,interleukin 1 beta,podoplanin(Pdpn),and factor VIII von Willebrand factor(F8VWF)were selected for analysis in mice.When MMP13 was inhibited,the expression level of PDPN decreased significantly in vitro.In HUVECs,overexpression of MMP13 led to an increase in the expression level of PDPN and induced platelet aggregation,while transfection of PDPN-siRNA weakened the ability of MMP13 to increase platelet aggregation.Conclusions:Inhibiting the expression of MMP13 could reduce the burden of DVT in mice.The mechanism involves downregulating the expression of Pdpn through MMP13,which could provide a novel gene target for DVT diagnosis and treatment.

激光联合牙周基础治疗对牙周炎患者牙周指标、龈下菌群及龈沟液脂联素、MMP-13、IL-1β的影响

目的:探讨激光联合牙周基础治疗对牙周炎患者牙周指标、龈下菌群及龈沟液脂联素、基质金属蛋白酶13(MMP-13)、白细胞介素1β(IL-1β)的影响。方法:回顾性分析2022年12月—2023年7月衡水市人民医院收治的牙周炎患者100例,按照治疗方法分为对照组(51例)和试验组(49例)。对照组给予牙周基础治疗,试验组在对照组基础上给予激光治疗。比较2组治疗前后的牙周指标、龈下菌群、龈沟液脂联素、MMP-13、IL-1β和骨代谢因子及临床疗效。采用SPSS 22.0软件包对数据进行统计学分析。结果:治疗后,试验组牙周袋深度(PD)、探诊出血指数(BOP)、牙龈指数(GI)和菌斑指数(PLI)较治疗前显著降低(P<0.05),对照组PD、BOP、PLI较治疗前显著降低(P<0.05);试验组PD、BOP、GI和PLI显著低于对照组(P<0.05)。治疗后,2组乳杆菌、梭杆菌和拟杆菌较治疗前显著降低(P<0.05),试验组显著低于对照组(P<0.05)。治疗后,2组龈沟液脂联素较治疗前显著升高(P<0.05),MMP-13、IL-1β较治疗前显著降低(P<0.05);试验组龈沟液脂联素显著高于对照组(P<0.05),龈沟液MMP-13、IL-1β显著低于对照组(P<0.05)。治疗后,2组龈沟液Ⅰ型胶原N端前肽(PINP)、Ⅰ型胶原C端肽(CXT)和骨钙素(BGP)较治疗前显著升高(P<0.05),试验组显著高于对照组(P<0.05)。试验组临床总有效率显著高于对照组(P<0.05)。结论:激光联合牙周基础治疗可有效改善牙周炎患者牙周指标,减少龈下菌群,提高龈沟液脂联素和骨代谢因子水平,降低龈沟液MMP-13、IL-1β水平,提高临床疗效。

血清IgE、IgA及MMP-13水平在复发性过敏性紫癜患儿中的表达及临床意义

目的探讨复发性过敏性紫癜(HSP)患儿血清中免疫球蛋白E(IgE)、免疫球蛋白A(IgA)以及基质金属蛋白酶-13(MMP-13)的表达水平及其临床意义,以此为临床治疗提供参考。方法选取2020年3月—2023年1月空军军医大学第二附属医院收治的HSP患儿161例为观察组,另选取同期于本院进行体检且各项正常儿童143例为对照组。观察组患儿于入院后次日清晨、对照组研究对象于体检当日早晨空腹状态下抽取静脉血5 mL。对比不同人群血清IgE、IgA、MMP-13水平,分析随访过程中观察组患儿复发情况;分析影响HSP患儿复发的单因素,采用多元logistic回归分析影响HSP复发的多因素。结果观察组患儿IgE、IgA、MMP-13水平均高于对照组,差异具有统计学意义(P<0.05)。经12个月的随访可知,161例HSP患儿中复发了36例(22.36%),其中再次出现关节疼痛15例,再次出现腹痛者10例,再次出现关节积液者7例,再次出现其他临床症状者4例,均归为复发组;随访期间,HSP患儿未出现临床症状的有125例(77.64%),归为未复发组。复发组患儿中饮食控制占比、血小板计数水平均低于未复发组,且乳酸脱氢酶、IgE、IgA、MMP-13水平均高于未复发组,差异均具有统计学意义(P<0.05)。多因素logistic回归分析结果显示:无饮食控制、血小板计数降低、乳酸脱氢酶水平升高、IgE水平升高、IgA水平升高、MMP-13水平升高为影响HSP复发的危险因素(P<0.05)。结论在复发性HSP患儿中,血清IgE、IgA及MMP-13水平均呈现上升趋势,并且三者同饮食不控制、血小板计数降低以及乳酸脱氢酶水平升高,均被视为影响HSP复发的危险因素。

Levels of matrix metalloproteinase-1 and tissue inhibitors of metalloproteinase-1 in gastric cancer

AIM:To evaluate the levels of preoperative serum matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in gastric cancer.METHODS:One hundred gastric cancer patients who underwent gastrectomy were enrolled in this study.The serum concentrations of MMP-1 and TIMP-1 in these patients and in fifty healthy controls were determined using an enzyme-linked immunosorbent assay.RESULTS:Higher serum MMP-1 and TIMP-1 levels were observed in patients than in controls (P < 0.001).Serum MMP-1 and TIMP-1 levels were positively associated with morphological appearance,tumor size,depth of wall invasion,lymph node metastasis,liver metastasis,perineural invasion,and pathological stage.They were not significantly associated with age,gender,tumor location,or histological type.CONCLUSION:Increased MMP-1 and TIMP-1 were associated with gastric cancer.Although these markers are not good markers for diagnosis,these markers show in advanced gastric cancer.

Clinical significance of matrix metalloproteinase-9 expression in esophageal squamous cell carcinoma

AIM: To evaluate the expression of matrix metalloproteinase-9 (MMP-9) and its clinical significance in esophageal squamous cell carcinoma (ESCC). METHODS: The expression of MMP-9 in 208 cases of ESCC was detected by immunohistochemistry (IHC) and its clinical significance in ESCC especially the relationship with the clinicopathological parameters was analyzed. RESULTS: The percentage of positive cases for MMP-9 detected by IHC was 49.0%. MMP-9 was mainly expressed in the cytoplasm of cancer cells especially in the invasive front. Only weak expression was detected in the stromal cells and no expression in non-cancerous mucosa. The expression of MMP-9 was positively correlated with poorer differentiation (P= 0.001<0.01), existence of vessel permeation (P= 0.027<0.05) and lymph node metastasis (P=0.027<0.05). CONCLUSION: The expression of MMP-9 correlates with the cancer cell differentiation, vessel permeation and lymph node metastasis. It may be a novel biomarker for the diagnosis and treatment of ESCC.

Expression of matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1 in ulcerative colitis

AIM: To examine the expression of metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in the colonic mucosa of patients with ulcer- ative colitis (UC). METHODS: Reverse transcription-polymerase chain re- action (RT-PCR) and immunohistochemistry were used to study the expression of MMP-1 and TIMP-1 at both mRNA and protein levels in patients with UC and con- trols. The relationship between MMP-1 mRNA, TIMP-1 mRNA, MMP-1 mRNA/TIMP-1 mRNA ratio and the sever- ity of clinical symptoms of the patients with UC were also analyzed. RESULTS: The expression of MMP-1 mRNA and TIMP-1 mRNA in the ulcerated and inflamed colonic mucosa was signifi cantly higher than that in the non-inflamed colonic mucosa (P < 0.001), but there was no statistically signif i- cant difference in the non-inflamed colonic mucosa of UC patients and normal controls (P > 0.05). The mRNA ex- pression of MMP-1 and TIMP-1 in ulcerated colonic mu- cosa of UC patients was increased by 80-fold and 2.2-fold, respectively when compared with the normal controls. In the inflamed colonic mucosa, the increase was 30-fold and 1.6-fold, respectively. Immunohistochemical analy- sis showed that among the ulcerated, inflamed, and non-inflamed colonic mucosae of UC patients and the normal controls, the positive rate of MMP-1 expression was 87%, 87%, 40% and 35% respectively, and the positive rate of TIMP-1 expression was 89%, 89%, 80% and 75%, respectively. Furthermore, the expression of MMP-1 mRNA, TIMP-1 mRNA and the MMP-1 mRNA/ TIMP-1 mRNA ratio were correlated with the severity of clinical symptoms (P <0.05).CONCLUSION: Excessive expression of MMP-1 in the diseased colonic mucosa causes excessive hydrolysis of the extracellular matrix (ECM) and ulceration in UC pa-tients. MMP-1 mRNA, TIMP-1 mRNA and MMP-1 mRNA/ TIMP-1 mRNA ratio can be used as biomarkers to judge the severity of clinical symptoms in patients with UC. Exogenous TIMP-1 or MMP-1 inhibitor therapy is a novel treatment for patients with UC.

Suppression of matrix metalloproteinase-2 via RNA interference inhibits pancreatic carcinoma cell invasiveness and adhesion

AIM:To investigate the inhibitory effects of RNA interference (RNAi) on expression of matrix metalloproteinase-2 (MMP-2) gene and invasiveness and adhesion of human pancreatic cancer cell line,BxPC-3.METHODS:RNAi was performed using the vector (pGPU6)-based small interference RNA (siRNA) plasmid gene silence system to specifically knock down MMP-2 expression in pancreatic cancer cell line,BxPC-3. Four groups of different specific target sequence in coding region of MMP-2 and one non-specific sequence were chosen to construct four experimental siRNA plasmids of pGPU6-1,pGPU6-2,pGPU6-3 and pGPU6-4,and one negative control siRNA plasmid of pGPU6 (-). MMP-2 expression was measured by reverse transcription polymerase chain reaction (RT-PCR) and Western blot. Cell proliferation and apoptosis were examined by methyl thiazolyl tetrazolium (MTT) and flow cytometry,respectively. The abilities of adhesion and invasion were detected by cell adhesion assay and cell invasion assay using Transwell chambers.RESULTS:The expression of MMP-2 was inhibited and the inhibitory effects of different sequence varied. pGPU6-1 group had the most efficient inhibitory effect,followed by pGPU6-2 and pGPU6-3 groups.Invasiveness and adhesion were more significantly reduced in pGPU6-1,pGPU6-2 and pGPU6-3 groups as compared with pGPU6 (-) and blank control groups. However,no difference concerning cell proliferation and apoptosis was observed after transfection between experiment groups and control groups.CONCLUSION:RNAi against MMP-2 successfully inhibited the mRNA and protein expression of MMP-2 in the pancreatic cancer cell line,BxPC-3,leading to a potent suppression of tumor cell adhesion and invasion without affecting cell proliferation and apoptosis. These findings suggest that the RNAi approach towards MMP-2 may be an effective therapeutic strategy for the clinical management of pancreatic tumor.

Matrix metalloproteinase-9-1562C>T polymorphism may increase the risk of lymphatic metastasis of colorectal cancer

AIM. To explore the role of the matrix metalloproteinase-9 （MMP-9） polymorphism in colorectal cancer （CRC） in a northeast Chinese population.METHODS： Genotyping of MNP-9-1562C〉T and 279R〉Q polymorphisms was carried out on blood samples from 137 colorectal cancer patients and 199 controls using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP）. Multivariate logistic regression models were used to calculate adjusted odds ratios （OR） and 95% confidence intervals （95% CI）.RESULTS： The distribution of IVllVlP-9 -2562C〉T and 279 R〉Q genotype was not significantly associated with the risk of CRC. However, the risk of Ilymph node metastasis of CRC was increased in patients with the -1562T allele （OR = 2.601; 95% CI = 1.160-5.835; P = 0.022）. The frequency of MMP-9 279RR ＋ RQ genotype was higher than the QQ genotype among CRC patients younger than sixty years old （OR = 0.102, 95% CI = 0.013-0.812; P = 0.012）.CONCLUSION： Our results indicated that the MMP-9- 1562C〉T polymorphism affects lymph node metastasis of CRC. In addition, the MMP-9 279R allele may lead to a younger age of onset of colorectal cancer.

Picroside Ⅱ down-regulates matrix metalloproteinase-9 expression following cerebral ischemia/reperfusion injury in rats

Studies have shown that Picroside Ⅱ attenuates inflammatory reactions following brain ischemia through the inhibition of the TLR-4-NF-KB signal transduction pathway, and ameliorates cerebral edema through the reduction of aquaporin-4 expression. Matrix metalloproteinase-9 （MMP-9）, located downstream of the TLR-4-NF-KB signal transduction pathway, can degrade the neurovascular matrix, damage the blood-brain barrier to induce cerebral edema, and directly result in neuronal apoptosis and brain injury, Therefore, the present study further observed MMP-9 expression in the brain tissues of rats with cerebral ischemia/reperfusion injury following Picroside Ⅱ treatment. Results demonstrated that Picroside Ⅱ significantly reduced MMP-9 expression in ischemic brain tissues, as well as neuronal apoptosis and brain infarct volume, suggesting Picroside Ⅱ exhibits neuroprotection by down-regulating MMP-9 expression and inhibiting cell apoptosis.

Expression and significance of angiostatin, vascular endothelial growth factor and matrix metalloproteinase-9 in brain tissue of diabetic rats with ischemia reperfusion

Objective: To discuss the expression and significance of angiostatin, vascular endothelial growth factor and matrix metalloproteinase-9 in the brain tissue of diabetic rats with ischemia reperfusion. Methods: A total of 60 male Wistar rats were randomly divided into the normal group, sham group, diabetic cerebral infarction group and single cerebral infarction group according to the random number table, with 15 rats in each group. The high sucrose diet and intraperitoneal injection of streptozotocin were performed for the modeling of diabetic rats, while the thread-occlusion method was employed to build the model of cerebral ischemia reperfusion. The immunohistochemical staining was performed to detect the expression of angiostatin, vascular endothelial growth factor(VEGF) and matrix metalloproteinase-9(MMP-9) in the brain tissue. Results: The expression of angiostatin after the reperfusion in the brain tissue of rats in the single cerebral infarction group and diabetic cerebral infarction group was increased 6 h after the reperfusion, reached to the peak on 1 d and then decreased gradually. The expression of angiostatin in the diabetic cerebral infarction group 6 h, 1 d, 3 d and 7 d after the reperfusion was significantly higher than that in the single cerebral infarction group(P<0.05). VEGF began to be increased 1 h after the reperfusion in the single cerebral infarction group and diabetic cerebral infarction group, reached to the peak at 6 h and then decreased gradually. The expression of VEGF in the diabetic cerebral infarction group at each time point after the reperfusion was significantly lower than that in the single cerebral infarction group(P<0.05). MMP-9 began to be be increased 1 h after the reperfusion in the single cerebral infarction group and diabetic cerebral infarction group, reached to the peak on 1 d and then decreased gradually. The expression of MMP-9 in the diabetic cerebral infarction group at each time point after the reperfusion was significantly higher than that in the single cerebral infarction group(P<0.05). Conclusions: The high glucose environment in which the diabetic cerebral infarction is occurred is to induce the formation of MMP-9 at first and then activate and increase the expression of angiostatin. Afterwards, the expression of VEGF is inhibited, resulting in the poor angiogenesis after cerebral infarction, which thus makes the injury of brain tissue after cerebral infarction even worse than the non-diabetes mellitus.

Relationship between matrix metalloproteinase-2 mRNA expression and clinicopathological and urokinase-type plasminogen activator system parameters and prognosis in human gastric cancer

AIM: To investigate the relationship between matrix metalloproteinase-2 (MMP-2) mRNA expression and clinicopathologic and urokinase-type plasminogen activator (uPA) system parameter and prognosis in human gastric cancer. METHODS: Expression of MMP-2 mRNA, uPA, and uPA-R mRNA in tumor tissues and ≥5 cm adjacent normal tissues from 67 cases of gastric cancer was studied using RT-PCR and Northern blot respectively.Survival analyses were done using the Kaplan-Meier method. RESULTS: The expression rates of MMP-2 mRNA,uPA and uPA-R mRNA in tumor tissues (31%,41%,and 51%, respectively) were significantly higher than those in ≥5 cm adjacent tissues (19%, 11%, and 9%; X2=4.59,43.58, and 53.24 respectively, P<0.05,0.0001,and 0.0001, respectively). Expression of MMP-2 mRNA was significantly correlated with lymph node metastasis (metastasis: 61.9%, no metastasis: 39.1%, X2= 7.61, P<0.05),Lauren's classification of diffuse/mixed types:54.2%,intestinal type: 26.3%,X2 = 4.25, P<0.05, expression of uPA and uPA-R mRNA (uPA+: 55.1%, uPA-: 22.2% and uPA-R+: 54.9%, uPA-R-: 18.8%, X2=5.72 and 6.40 respectively, P<0.05).Kaplan-Meier survival analysis of MMP-2 mRNA expression did not show significant difference in all 67 cases, but revealed an association of the expression of MMP-2 mRNA, uPA, and uPA-R mRNA with worse prognosis (P= 0.0083, 0.0160, and 0.0094, respectively). CONCLUSION: MMP-2 may play an important role in the development of invasion and metastasis of gastric cancer.

Correlation of RECK with Matrix Metalloproteinase-2 in Regulation of Trophoblast Invasion of Early Pregnancy

To study the role of the reversion-inducing-cysteine-rich protein with Kazal motifs （RECK） gene and matrix metalloproteinase-2 （MMP-2） in the regulation of trophoblast invasion of early pregnancy. Immunohistochemistry, Western blot and gelatin zymography were used to detect the RECK protein expression localization, expression level and MMP-2 activation level in the placental tissues harvested from 52 normal pregnant women （27 in the early pregnancy, 25 in the term pregnancy）. Immunohistochemistry showed that RECK expression was found both in villous tissues of early pregnancy group and term pregnancy group and was mainly observed in cell membrane and cytoplasm of cytotrophoblasts and syneytiotrophoblasts. RECK expression increased with gestational time. RECK expression of early pregnancy group was significantly lower than that of term pregnancy group （P〈0.05）. RECK expression was significantly lower in cellular column （CC） with invasion ability. Western blot showed that the RECK protein expression in early pregnancy group was significantly lower than that in term pregnancy （P〈0.05）. The optical density values of RECK protein expression in early pregnancy group and term pregnancy group were 1.35±0.14 and 2.68±0.26, respectively, while MMP-2 activation ratio was contrary to RECK protein expression and decreased with the gestation time （P〈0.01）. The MMP-2 activation ratios of early pregnancy group and term pregnancy group were 0.46±0.05 and 0.10±0.02, respectively. The expression of the tumor inhibitory gene RECK was positively related with the invasion ability of trophoblasts, while the invasion gene MMP-2 was negatively related with the ability. The interaction between RECK and MMP-2 may play an important role in the regulation of the trophoblast invasion in early pregnancy.