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1.
Using JEG-3 and BeWo cells, we examined the effect of “real life” mixtures of polycyclic aromatic hydrocarbons (PAHs), at doses reported in maternal blood (Mix I) and in placental tissue (Mix II), on human chorionic gonadotropin (hCG), placental lactogen (hPL) and placental growth factor (hPLGF) secretion, protein expression and immunolocalization. Additionally, the action of PAH mixtures on basal and hormone-stimulated matrix metalloproteinase-2 (MMP-2), MMP-9 and vascular endothelial growth factor (VEGF) protein expression was evaluated. Under basal conditions, the PAH mixtures increased hCG and decreased hPLGF levels in both cell lines, while hPL expression was stimulated in JEG-3 and inhibited in BeWo. There was no effect on the MMP-2/MMP-9 ratio or VEGF expression. In hormone-stimulated cells, PAH mixtures changed the MMP-2/MMP-9 ratio in JEG-3 cells in favor of MMP-9, while in BeWo MMP-2 was favored. The effect on VEGF expression was cell specific and dependent on the mixture. In hCG-treated cells, only Mix II inhibited VEGF expression in JEG-3 cells. Neither PAH mixtures affected this protein in BeWo cells. In hPL-treated cells, Mix I had a stimulatory effect in JEG-3 cells, while Mix II exerted an inhibitory effect in BeWo cells. In hPLGF-treated cells, Mix II decreased in JEG-3 cells, but in BeWo cells, both mixtures increased VEGF expression. Considering that the evaluated protein hormones play crucial roles in angiogenesis and neovascularization in the placenta, “real life” PAH mixtures by disrupting protein hormones levels, the MMP-2/MMP-9 ratio and VEGF expression can lead to insufficiency and many pregnancy-related disorders. 相似文献
2.
基质金属蛋白酶及其抑制剂在子宫内膜癌的侵袭和转移中发挥着重要的作用。肿瘤的新生血管对肿瘤的发生、发展、转移及预后有着重要作用。微血管密度是衡量血管生成的定量指标。基质金属蛋白酶抑制剂可抑制血管的生成和MMPs对细胞外基质的降解。现将他们与子宫内膜癌的关系综述如下。 相似文献
3.
Epidemiological evidence suggests an inverse relationship between prostate cancer and serum vitamin D levels. We examined
the ability of cholecalciferol (vitamin D3), a calcitriol precursor, to inhibit or reverse cellular changes associated with malignant transformation and invasion and
explored its mechanisms of action. The RWPE2-W99 human prostate epithelial cell line, which forms slow-growing tumors in nude
mice, was used because it mimics the behavior of the majority of primary human prostate cancers. Cholecalciferol, at physiological
levels: (i) inhibited anchorage-dependent and -independent growth; (ii) induced differentiation by decreasing vimentin expression
with a concomitant decrease in motility/chemotaxis; (iii) decreased MMP-9 and MMP-2 activity with concomitant decrease in
invasion; and (iv) exerted its effects by up-regulating vitamin D receptor (VDR), retinoid-X receptor-α (RXR-α), and androgen
receptor (AR) in a dose-dependent manner. Furthermore, we found that RWPE2-W99 prostate cancer cells, similar to RWPE-1 cells
(Tokar and Webber. Clin Exp Metast 2005; 22: 265–73), constitutively express the enzyme 25-hydroxylase CYP27A1 which is markedly
up-regulated by cholecalciferol. Cholecalciferol has effects similar to those of calcitriol on growth, MMP activity, and VDR.
The ability of CYP27A1 to catalyze the conversion of cholecalciferol to 25(OH)D3 and of 25(OH)D3 to calcitriol has been reported. RWPE2-W99 cells, similar to RWPE-1 cells, appear to have the rare ability to locally convert
cholecalciferol to the active hormone calcitriol. Because it can inhibit cellular changes associated with malignant transformation
and invasion, we propose that cholecalciferol may be an effective agent for the treatment of prostate cancer. 相似文献
4.
Conversion of highly malignant colon cancer from an aggressive to a controlled disease by oral administration of a metalloproteinase inhibitor 总被引:3,自引:0,他引:3
Zili An Xiaoen Wang Neville Willmott Surinder K. Chander Simon Tickle Andrew J. P. Docherty Andrew Mountain Andrew T. Millican Richard Morphy John R. Porter R. Ola Epemolu Tetsuro Kubota A. R. Moossa Robert M. Hoffman 《Clinical & experimental metastasis》1997,15(2):184-195
In this study, we describe the activity of CT1746, an orally-active synthetic MMP inhibitor that has a greater specificity for gelatinase A, gelatinase B and stromelysin than for interstitial collagenase and matrilysin, in a nude mouse model that better mimics the clinical development of human colon cancer. The model is constructed by surgical orthotopic implantation (SOI) of histologically-intact tissue of the metastatic human colon tumor cell line Co-3. Animals were gavaged with CT1746 twice a day at 100 mg/kg for 5 days after the SOI of Co-3 for 43 days. In this model CT1746 significantly prolonged the median survival time of the tumor-bearing animals from 51 to 78 days. Significant efficacy of CT1746 was observed on primary tumor growth (32% reduction in mean tumor area at day 36), total spread and metastasis (6/20 treated animals had no detectable spread and metastasis at autopsy compared to 100% incidence of secondaries in control groups). Efficacy of CT1746 could also be seen on reducing tumor spread and metastasis to individual organ sites such as the abdominal wall, cecum and lymph nodes compared to vehicle and untreated controls. We conclude that chronic administration of a peptidomimetic MMP inhibitor via the oral route is feasible and results in inhibition of solid tumor growth, spread and metastasis with increase in survival in this model of human cancer, thus converting aggressive cancer to a more controlled indolent disease. 相似文献
5.
目的揭示金属蛋白酶类(MMPs)及层粘连蛋白受体(LN-R)与人黑色素瘤细胞侵袭转移的关系,并探讨MMPs及IN-R用以判断肿瘤细胞侵袭转移的可能性。方法通过流式细胞术(FCM)定量研究和蛋白酶活性分析(Zymography),对具有不同潜在转移能力的人黑色素瘤细胞系(WM35,WM134b,WM983a,WM451)进行MMPs及瘤细胞表面67000LN-R的荧光阳性率和全部细胞的平均荧光强度测定。结果早期WM35不产生MMPs;WM1341b仅产生MMP2,不产生MMP9;进展期WM983a和远处转移瘤株WM451既产生MMP2又产生MMP9。瘤细胞表面67000LN-R的荧光阳性率和全部细胞的平均荧光强度大小顺序为WM451>WM983a>WM1341b>WM35。结论MMPS和LN-R与人黑色素瘤细胞侵袭转移能力的获得之间关系密切,并可作为较特异的肿瘤侵袭转移标记物应用于肿瘤研究与治疗中。 相似文献
6.
MMPs及其调控因子与滋养层细胞的侵袭 总被引:5,自引:2,他引:5
滋养层细胞的侵袭行为受严格的时空调控 ,细胞外基质降解是滋养层细胞侵袭过程的关键步骤 ,也是成功妊娠建立的必要条件。基质金属蛋白酶 ( MMPs)是参与细胞外基质降解的关键酶 ,因此也是滋养层细胞侵袭行为调控的关键因子 ,滋养层细胞的自分泌和子宫的旁分泌因子如 :激素、细胞因子、生长因子、基质蛋白等可调节 MMPs活性 ,进而参与滋养层细胞侵袭过程 相似文献
7.
目的探讨高温治癌与基质金属蛋白酶系统之间的关系,以期阐明高温抑制肿瘤细胞侵袭及转移的机理.方法对舌癌细胞Tca-8113进行体外43℃加温,通过免疫组化、流式细胞术及明胶酶谱活性分析等方法进行分析,以研究加温后该舌癌细胞MMP-9、MMP-2表达量及其活性的改变.结果加温与未加温细胞MMP-9、MMP-2均有表达,但加温后的细胞MMP-9和MMP-2蛋白表达量减少,并且加温后的细胞MMP-9和MMP-2的活性较未加温细胞明显下降.结论高温能通过调节基质金属蛋白酶(MMP-9、MMP-2)的表达量及其活性来抑制肿瘤细胞的侵袭、转移能力. 相似文献
8.
目的:研究乳腺癌组织中表皮生长因子受体-2(HER-2)和金属蛋白酶组织抑制剂(TIMP—1)的表达情况,探讨其与乳腺癌转移及预后的相关性,寻找能够有效判断乳腺癌转移潜能的分子生物学指标。方法:采用免疫组化二步法检测60例乳腺癌组织中HER-2和TIMP—1的表达情况。结果:HER-2和TIMP—1的阳性表达率与临床分期无明显相关性,P〉0.05;HER-2的阳性表达率,在无淋巴结转移组差异无统计学意义,P〉0.05,TIMP—1的阳性表达率,在有淋巴结转移组(56.7%,17/30)高于无淋巴转移组(23.0%,7/30),差异有显著性,P〈0.01。HER-2和TIMP—1在乳腺癌组织中的表达呈显著正相关,r=0.306,P:0.018。患者的总生存率在HER-2有表达组明显低于HER-2无表达组,P〈0.05,在TIMP—1有无表达组的差异无统计学意义,P〉0.05。结论:在乳腺癌组织中TIMP—1可能有促进淋巴管转移的作用,但TIMP—1不能作为不良预后指标独立检测;HER-2可作为不良预后指标独立检测。 相似文献
9.
三七复合有效成分对恒河猴子宫炎性出血内膜组织中基质金属蛋白酶1、9及其抑制剂表达的影响 总被引:6,自引:0,他引:6
目的探讨三七复合有效成分对恒河猴子宫炎性出血内膜组织中基质金属蛋白酶1、9及其抑制剂表达的影响.方法运用免疫组化链霉素抗生物素蛋白-过氧化物酶染色法(SP)检测细菌感染性子宫出血模型组、三七复合有效成分组及正常对照组恒河猴子宫内膜组织中基质金属蛋白酶1、9(MMP-1、9)及其抑制剂(TIMP-1)的表达.结果模型组子宫内膜基质细胞、腺上皮细胞胞浆中MMP-1、9均呈高表达状态,与三七复合有效成分组及正常对照组比有显著性差异,三七复合有效成分组与正常组相比没有差异,而三纽子宫内膜TIMP-1的表达水平相似.结论三七复合有效成分可能通过抑制基质MMP-1、9的过度表达而起到止血及修复子宫内膜的作用. 相似文献
10.
阿托伐他汀减轻兔血管损伤后再狭窄机制的研究 总被引:1,自引:0,他引:1
目的观察阿托伐他汀对兔血管损伤后再狭窄的干预作用,探讨其与PKC、MMPs的关系。方法将40只健康日本大耳兔,♂,分为5组,每组8只,模型组及阿托伐他汀高(2 mg.d 1)、中(1 mg.d 1)、低(0.5 mg.d 1)剂量组均行髂动脉二次损伤造模术,假手术组仅结扎股动脉。一月后取靶血管切片HE染色,图像分析仪检测各组内膜面积、中膜面积、管腔面积、内膜增生指数及狭窄指数;免疫组化检测各靶血管MMP-2、MMP-9、PKC表达。结果经髂动脉二次损伤能成功建立血管成形术后再狭窄模型。与模型组相比,随剂量升高,阿托伐他汀各组内膜面积、中膜面积、膜增生指数及狭窄指数显著降低,管腔面积显著增加(P<0.01),与此同时,靶血管MMP-2、MMP-9及PKC表达均显著降低,差异有统计学意义(P<0.01)。结论阿托伐他汀能显著减轻兔血管成形术后再狭窄,其机制可能与通过PKC途径抑制靶血管MMPs表达有关。 相似文献