MMP-7表达在早期胃癌淋巴结转移中的预测地位

目的基质金属蛋白酶家族(MMPs)在胃癌的发病机制和转移机制中发挥着重要作用,本实验研究早期胃癌的淋巴结转移和MMPs表达之间的相互关系,希望能为临床预测早期胃癌是否存在淋巴结转移提供一些帮助。方法应用免疫组织化学方法,检测34例淋巴结阳性与80例淋巴结阴性的pT1早期胃癌组织中MMP-2、MMP-7、MMP-9的表达情况,并用Multivariete统计学方法进行MMPs表达和淋巴结转移之间的相关性分析。结果淋巴结转移阳性的早期胃癌组织中MMP-7阳性表达率为82.3%,而淋巴结转移阴性的早期胃癌组织MMP-7阳性表达率为54.4%,二者相比统计学有显著差异(P<0.05)。反而,MMP-9和MMP-2在早期胃癌组织中的阳性表达率与淋巴结转移情况间均无统计学意义。Multivariete分析表明,MMP-7表达是预测早期胃癌是否存在淋巴结转移的重要因子(P<0.05),同时肿瘤细胞的淋巴管浸润也是预测早期胃癌是否存在淋巴结转移不可缺少的因子(P<0.001)。结论 MMP-7表达与早期胃癌淋巴结转移之间有明显的相关性,可作为早期胃癌是否存在淋巴结转移的重要预测指标。     

白头翁皂苷 B4调控去乙酰化酶 6对胃癌细胞转移和放疗敏感性的影响

目的探讨白头翁皂苷 B4(AB4)对胃癌细胞增殖、迁移、侵袭及放疗敏感性的影响及其分子机制。方法该研究起止时间为 2018年 4月至 2019年 10月。体外培养人正常胃黏膜上皮细胞 GES-1与胃癌细胞 HGC-27，采用不同浓度( 25、50、100 μmol/L)的 AB4处理 24 h，通过 MTT法检测细胞存活率并筛选 AB4适宜浓度用于后续研究。 Transwell实验检测 HGC-27细胞迁移及侵袭能力。细胞克隆形成实验检测 AB4对 HGC-27细胞放射敏感性的影响；蛋白质印迹法检测 AB4对 HGC-27细胞中去乙酰化酶 6(SIRT6)蛋白表达的影响；干扰 SIRT6表达联合 AB4处理后，采用上述检测方法检测 HGC-27细胞增殖、迁移、侵袭及放射敏感性；蛋白质印迹法检测 DNA激活蛋白激酶催化亚基( DNA-PKcs)、 DNA双链修复蛋白 Rad51、DNA修复酶 Ku80、基质金属蛋白酶 -2(MMP-2)、基质金属蛋白酶 -9(MMP-9)蛋白表达水平。结果与 NC组相比， AB4处理后 HGC-27细胞存活率［( 100.01±9.57)%比( 86.57±6.58)%、(65.45±8.45)%、(49.58±7.96)%］显著降低( P<0.05)，迁移细胞数［( 98.47±8.79)个比(43.57±6.53)个］与侵袭细胞数［(88.42±9.32)个比( 45.56±5.13)个］显著减少( P<0.05)MMP-2、MMP-9蛋白表达水平显著降低(P<0.05)，SIRT6蛋白表达水平(0.42±0.03比 1.03±0.15)显著升高( P<0.05)；细胞克隆形成，实验显示 AB4可降低 HGC-27细胞存活分数( P<0.05)增加增敏比，降低 Rad51、DNA-PKcs、Ku80的表达水平( P<0.05)；干扰 SIRT6表达联合 AB4处理后，迁移细胞数［(44.25±5.52)个，比( 86.47±11.16)个］与侵袭细胞数［(48.56±6.29)个比( 90.17±12.13)个］显著增多( P<0.05)，MMP-2、MMP-9 蛋白相对表达量显著升高( P<0.05)细胞存活分数显著升高( P<0.05)Rad51、DNA-PKcs、Ku80蛋白表达水平明显升高( P<0.05)。结论促进 SIRT6的表达进而发挥抑癌细胞 HGC-27增殖、迁移及侵袭的作用，并增加胃癌细胞的放射敏感性。     

Response of MG63 osteoblasts on bacterial challenge is dependent on the state of differentiation

The present in vitro study examines molecular processes that are relevant during bone homeostasis after Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis infection with a focus on the differentiation level of osteoblasts. Regenerative processes are often hindered by the recurrence of bacterial infections, which can ultimately provoke a severe destruction of bone tissue. To obtain more detailed insights into such a complex scenario, we have used undifferentiated MG63 osteoblast‐like cells as an experimental paradigm to examine the impact of two oral pathogens, A. actinomycetemcomitans and P. gingivalis, on proliferation, cytotoxicity and osteogenic differentiation. Cell culture experiments were performed to analyze cellular behavior. The level of genes interfering with bone tissue integrity (matrix metalloproteinases and their tissue inhibitors) and osteogenic markers (alkaline phosphatase, Runx2, human β‐defensin‐2) was compared in undifferentiated versus differentiated MG63 cells using real‐time polymerase chain reaction. Functional activity of matrix metalloproteinases was quantified by zymography. Western blot analysis was used to verify the phosphorylation state of mitogen‐activated protein kinases p38 and extracellular‐signal‐regulated kinases 1/2. When co‐cultured with undifferentiated MG63 cells, oral pathogens provoked distinct cellular effects. Only A. actinomycetemcomitans reduced cell proliferation, increased cell death, and induced osteogenic differentiation. A comparison of matrix metalloproteinase network stability in the presence of oral pathogens revealed a partial sensitivity towards P. gingivalis but not A. actinomycetemcomitans. So, beside the proof of concept that MG63 cells co‐cultured with oral pathogens can serve as an in vitro model for mimicking destructive and regenerative events after bacterial infections, our data indicate that double infections might counterbalance otherwise positive effects.     

Molecular imaging reveals time course of matrix metalloproteinase activity in acute cutaneous vasculitis in vivo

Matrix metalloproteinases (MMPs) play a critical role in various pathological conditions including cutaneous inflammation. Thus far, serial assessment of MMP activity in ongoing inflammation is hampered due to technical limitations. Here, we present an innovative method for longitudinal detection of MMP activity by in vivo imaging. First, we analysed skin sections from patients suffering from leucocytoclastic vasculitis (LcV) and detected a significant MMP signal via immunofluorescence staining. Then, we mimicked LcV in mice in a well‐studied model of immune complex‐mediated vasculitis (ICV). This acute inflammatory process was serially visualized in vivo using the fluorescence‐labelled MMP tracer Cy5.5‐AF443. The deposition of fluorescence‐labelled immune complexes and MMP tracer distribution was visualized repeatedly and non‐invasively by fluorescence reflectance imaging. In correlation with the presence of MMP‐2 and MMP‐9 in immunofluorescence stainings, Cy5.5‐AF443 accumulated in ICV spots in the skin of C57BL/6 mice. This tracer accumulation could also be observed in mice equipped with a dorsal skinfold chamber, where microscopic observations revealed an increased recruitment of fluorescence‐labelled leucocytes during ICV. The specificity of the MMP tracer was supported by (i) analysis of mice deficient in functional β₂‐integrins (CD18^?/?) and (ii) subsequent MMP immunofluorescence staining. These findings let us conclude that MMP accumulation in the acute phase of ICV depends on β₂‐mediated leucocyte recruitment. In summary, we show that MMPs are involved in ICV as determined by Cy5.5‐AF443, a new optical marker to longitudinally and non‐invasively follow MMP activity in acute skin inflammation in vivo.     

Contraction‐induced Mmp13 and −14 expression by goat articular chondrocytes in collagen type I but not type II gels

Collagen gels are promising scaffolds to prepare an implant for cartilage repair but several parameters, such as collagen concentration and composition as well as cell density, should be carefully considered, as they are reported to affect phenotypic aspects of chondrocytes. In this study we investigated whether the presence of collagen type I or II in gel lattices affects matrix contraction and relative gene expression levels of matrix proteins, MMPs and the subsequent degradation of collagen by goat articular chondrocytes. Only floating collagen I gels, and not those attached or composed of type II collagen, contracted during a culture period of 12 days. This coincided with an upregulation of both Mmp13 and ?14 gene expression, whereas Mmp1 expression was not affected. The release of hydroxyproline in the culture medium, indicating matrix degradation, was increased five‐fold in contracted collagen I gels compared to collagen II gels without contraction. Furthermore, blocking contraction of collagen I gels by cytochalasin B inhibited Mmp13 and ?14 expression and the release of hydroxyproline. The expression of cartilage‐specific ECM genes was decreased in contracted collagen I gels, with increased numbers of cells with an elongated morphology, suggesting that matrix contraction induces dedifferentiation of chondrocytes into fibroblast‐like cells. We conclude that the collagen composition of the gels affects matrix contraction by articular chondrocytes and that matrix contraction induces an increased Mmp13 and ?14 expression as well as matrix degradation. Copyright © 2011 John Wiley & Sons, Ltd.     

Peripheral levels of matrix metalloproteinase-9, interleukin-6, and C-reactive protein are elevated in patients with acute coronary syndromes: correlations with serum troponin I

BACKGROUND: Acute coronary syndromes (ACS) are characterized by activation of systemic and local inflammatory mediators. The interrelation between these soluble inflammatory markers and their association with markers of myocardial necrosis have not been extensively studied. HYPOTHESIS: The study was undertaken to evaluate the association of the systemic levels of matrix metalloproteinase-9 (MMP-9) and the tissue inhibitor of metalloproteinase-1 (TIMP-1), with C-reactive protein (CRP), interleukin-6 (IL-6), and serum troponin-I in patients admitted with ACS. METHODS: Analysis of serum concentrations of the above inflammatory markers was performed in 53 patients with unstable angina (UA) and in 15 with non-ST-segment elevation myocardial infarction (NSTEMI) within 48 h of admission, and 34 patients with stable coronary artery disease. RESULTS: Compared with patients with stable angina, those with ACS had elevated admission levels of MMP-9 (p = 0.04), CRP (p < 0.001), and IL-6 (p = 0.001), but not TIMP-1 (p = 0.55). Compared with patients with UA, those with NSTEMI also had higher levels of IL-6 (p < 0.001), CRP (p = 0.002), and MMP-9 (p = 0.05). CONCLUSIONS: In patients with ACS, the admission levels of inflammatory mediators, including MMP-9, CRP, and IL-6 are significantly elevated, specifically in association with serum troponin I. Systemic and local markers of inflammatory activity may be directly associated with myocardial injury.     

Blockade of Rho/Rho-associated coiled coil-forming kinase signaling can prevent progression of hepatocellular carcinoma in matrix metalloproteinase-dependent manner

Aim:  There is growing evidence that the Rho/Rho-associated coiled coil-forming kinase (ROCK) signaling pathway is upregulated in tumors and plays a key role in cancer invasion and metastasis. Our aim was to test the anticancer effects of Rho/ROCK inhibitor, Y-27632, including possible mechanisms in a highly-metastasizing hepatocellular carcinoma (HCC) mouse model on its secretion of matrix metalloproteinase (MMP) and tumor progression.
Methods:  Following orthotopic implantation of CBO140C12 HCC tumor fragments into the liver of mice, the mice were randomly assigned to a Y-27632-treated group or control group. After treatment for 4 weeks, specimens were obtained to evaluate tumor size, metastases, and immunohistochemical findings. In vitro , we examined the effects of Y-27632 and RhoC siRNA on MMP-2 and -9 expressions, invasiveness, and apoptosis in cultured tumor cells.
Results:  Both RhoA and RhoC were upregulated in HCC-bearing livers, and Y-27632 significantly inhibited not only tumor growth and intrahepatic metastasis ( P  < 0.05), but also tumoral MMP-9 expression. Moreover, Y-27632 treatment resulted in large necrotic areas in tumors. In vitro , Y-27632 and RhoC siRNA reduced MMP-2 and -9 expressions, as well as the chemotactic migration of tumor cells dose-dependently, and increased apoptosis eight times.
Conclusion:  Y-27632 suppresses progression and limits the intrahepatic metastasis of established HCC. This could be linked to the decreased MMP expression and induction of apoptosis in tumor cells. Rho signaling may prove to be a productive target in anticancer therapy.