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71.
Decidualization of endometrium, which is characterized by endometrial stromal cell (ESC) decidualization, vascular reconstruction, immune cell recruitment, and plentiful molecule production, is a crucial step for uterus to become receptive for embryo. When implantation takes place, ESCs surround and directly interact with embryo. Decidualized stromal cells (DSCs) are of great importance in endometrial decidualization, having a broad function in regulating immune activity and vascular remodeling of uterus. DSCs are shown to have a higher metabolic level and looser cytoskeleton than ESCs. What's the origin of ESCs and how ESCs successfully transform into DSCs had puzzled scientists in the last decades. Breakthrough had been achieved recently, and many studies had elucidated some of the characters and functions of DSCs. However, several questions still remain unclear. This paper reviews current understanding of where ESCs come from and how ESCs differentiate into DSCs, summarizes some characters and functions of DSCs, analyzes current studies and their limitations and points out research areas that need further investigation.  相似文献   
72.
Yu H  Zhao G  Li H  Liu X  Wang S 《Gene》2012,497(2):301-306
The present study was designed to investigate the underlying molecular mechanism for Angiotensin II type 1 receptor blockers (ARBs) mediated cardio-protection against pressure overload-induced cardiac remodeling with a focus on Smad7. ROCK-1, Smad3 and fibronectin expressions were increased in male C57BL/6 mice underwent transverse aortic constriction (TAC) for 2weeks. Treatment with Candesartan (2mg/kg per day) could effectively downregulate Smad3 and fibronectin accompanied by upregulating of Smad7. Further data showed that Candesartan inhibited TGF-β1 signal-induced epithelial-to-mesenchymal transition (EMT) through attenuating matrix metalloproteinases (MMP-9), such effect was abolished by knocking-down Smad7. Moreover, TAC for 2weeks caused increased collagen deposition, thickness of left ventricular anterior and posterior wall at end-diastole (LVAWD and LVPWD) and LVEF% reduction, which were reversed by treatment with Candesartan, but failed after knocking-down Smad7. In addition, LV dP/dt(max) and dP/dt(min) were increased by TAC for 2weeks, and treatment with Candesartan or Nifedipine effectively depressed the high levels of dP/dt(min) induced by TAC. However, only Candesartan-mediated protective role in improving cardiac function was suppressed by tail-vein injection of Smad7 siRNA. This study uncovered a novel role for ARBs in preventing pressure overload-induced cardiac remodeling via Smad7 upregulation, which suppressed MMP-9 expression and TGF-β1 signal-mediated EMT progress.  相似文献   
73.
细胞外基质金属蛋白酶诱导因子(CD147)是一种高度糖基化的跨膜蛋白,属于免疫蛋白超家族成员。CD147 为多功能型蛋 白,可以参与人体的多种病理生理机制,其通过调节血管内皮生长因子(VEGF)和基质金属蛋白酶(MMPs)的表达参与恶性肿瘤的新生血管的生成及多重耐药性的产生。近年来随着对CD147 在肿瘤发生发展中的研究不断深入,越来越多的发现使得CD147在肿瘤进展中的作用日益凸显。已经明确了其对肿瘤的进展及治疗的作用,在多种肿瘤中高表达,并随着肿瘤的恶性程度增高而 增加,可以作为某些恶性肿瘤治疗的靶点。然而,CD147 其他的功能包括充当T 细胞的活化剂、神经识别分子和受体伴侣亲环素A的生理和病理机制还未明确。因此,有必要探索CD147 在肿瘤中的特定功能,并阐明其产生机制是至关重要的。在此研究的基础上,现就CD147 与MMPs、VEGF之间相互作用对肿瘤的转移和浸润的影响作一综述。  相似文献   
74.
Cancer complexity constantly challenges the way that clinicians manage breast cancer therapy. Tumor heterogeneity and intratumoral stroma characteristics allow cells with different phenotypes and deregulated apoptotic, proliferative and migration abilities to co-exist contributing to a disappointing therapeutic response. While new approaches are being associated with conventional chemotherapy, such as hormonal therapy or target monoclonal antibodies, recurrence and metastasization are still observed. Membrane transporters are the cell's first line of contact with anticancer drugs having a major role in multidrug resistance events. This structural-based activity enables the cell to be drug-resistant by decreasing drug intracellular concentration through an efflux-transport mechanism, mainly associated with overexpression of ATP-binding cassette (ABC) proteins. This review focuses on some of the important structural and biological properties of the malignant cell and tumor microenvironment, addressing the role of the membrane ABC transporters in therapeutic outcomes, and highlighting related molecular pathways that may represent meaningful target therapies.  相似文献   
75.

Purpose

Posterior tibial tendon (PTT) is particularly vulnerable and its insufficiency is recognized as the main cause of adult acquired flatfoot. Some patients have a predisposition without clinically recognized cause, suggesting that individual characteristics play an important role in tendinopathy. The objective of the present study is to investigate the association of − 519 (rs1144393) matrix metalloproteinase-1 (MMP-1) polymorphism and the − 1607 (rs1799750) and − 519 MMP-1 haplotypes and risk of PTT dysfunction.

Methods

The test group included 50 females who presented PTT dysfunction Grade 2 or 3, and who were submitted to surgical treatment, with histopathological examination of the tendon and magnetic resonance image (MRI) confirming tendinopathy, while the control group was 100 asymptomatic women who present intact PTT at MRI. We analyzed functional polymorphisms MMP-1 and their haplotypes using polymerase chain reaction and restriction fragment length analysis.

Results

There was a significant difference in the presence of the different alleles and genotypes between the control group and test group for the MMP-1 gene (p ≤ 0.01). The G allele of the − 519 MMP-1 polymorphism increased susceptibility to degeneration in the PTT tendon and seems to be a genetic risk factor. Global haplotype analysis indicated a significant difference between both groups (p < 0.0001). Haplotypes G–2G and A–2G had statistically significant risk effect on PTT insufficiency. G–2G, p < 0.001; OR = 5.72 (CI, 2.84–11.52) and A–2G p = 0.002, OR = 3.95 (CI, 1.65–9.44).

Conclusion

According to our results, − 519 MMP-1 isolated and − 1607/− 519 MMP-1 haplotypes are associated to tendinopathy in posterior tibial tendon.  相似文献   
76.
Angiogenesis is a process required not only for embryonal development but is encountered in wound healing and in pathological situations such as tumour growth. In vitro, formation of capillary-like structures can be induced by seeding human microvascular endothelial cells (HDMECs) on top of a fibrin matrix in the presence of phorbol 12-myristate 13-acetate (PMA) as a stimulating agent. In this study, we show that supernatants collected from high-invasive melanoma cells (BLM) induce the formation of tubular structures similar to PMA treatment whereas supernatants from low-invasive cells (WM164) did not. Analysis of proteins secreted into the supernatant of both melanoma cell lines identified differential expression of several pro-angiogenic proteins in high- and low-invasive melanoma cells. Vascular endothelial growth factor (VEGF) was strongly expressed by high- but not by low-invasive melanoma cells. Neutralisation of VEGF as well as inhibition of matrix metalloproteases (MMPs) using the broad spectrum MMP inhibitor 1,10-phenanthroline, both strongly reduced the melanoma-induced tube formation. PMA treatment of HDMECs on a fibrin matrix stimulated MT1-MMP synthesis, indicating that this protease is involved in PMA-induced angiogenesis. In addition, stimulation of HDMECs by supernatants of BLM melanoma cells resulted in a strong induction of ADAM-15, which is known to act as a metalloproteinase. In conclusion, these results show that VEGF released by melanoma cells is an important mediator of neo-vascularisation and that this process depends on the presence of metalloproteinases.  相似文献   
77.
Invasive behavior is the pathological hallmark of malignant gliomas, being responsible for the failure of surgery, radiation, and chemotherapy. Matrix metalloproteinases (MMPs) are essential for proper ECM remodeling and invasion. The tumor and metastasis suppressor RECK protein regulates at least three members of the MMPs family: MMP-2, MMP-9, and MT1-MMP. In order to mimic the in vivo invasion process, A172 and T98G, respectively, non-invasive and invasive human glioblastoma cell lines, were cultured onto uncoated (control) or type I collagen gel-coated surface, and maintained for up to 7 days to allow establishment of the invasive process. We show that the collagen substrate causes decreased growth rates and morphological alterations correlated with the invasive phenotype. Electronic transmission microscopy of T98G cells revealed membrane invaginations resembling podosomes, which are typically found in cells in the process of crossing tissue boundaries, since they constitute sites of ECM degradation. Real time PCR revealed higher RECK mRNA expression in A172 cells, when compared to T98G cells and, also, in samples obtained from cultures where the invasive process was fully established. Interestingly, the collagen substrate increases RECK expression in A172 cells and the same tendency is displayed by T98G cells. MMPs-2 and -9 displayed higher levels of expression and activity in T98G cells, and their activities are also upregulated by collagen. Therefore, we suggest that: (1) RECK downregulation is critical for the invasiveness process displayed by T98G cells; (2) type 1 collagen could be employed to modulate RECK expression in glioblastoma cell lines. Since a positive correlation between RECK expression and patients survival has been noted in several types of tumors, our results may contribute to elucidate the complex mechanisms of malignant gliomas invasiveness.  相似文献   
78.
In general, tumors cells that are resistant to apoptosis and increase angiogenesis are a result of the hypoxic responses contributing to the malignant phenotype. In this study, we developed a chronic hypoxic cell model (HMLL), by incubating the prostate cancer MatLyLu cells in a hypoxic chamber (1% O2) over 3 weeks. Surviving cells were selected through each cell passage and were grown in the hypoxic condition up to 8 weeks. This strategy resulted in survival of only 5% of the cells. The surviving hypoxic cells displayed a greater stimulation on hypoxic adaptive response, including a greater expression of glucose transporter1 (Glut1) and VEGF secretion. In addition, higher invasion activity was observed in the chronic hypoxic HMLL cells as compared to MatLyLu cells exposed to acute hypoxia (1% O2, 5 h) using the matrigel assay. To further examine the role of HIF-1α in tumor progression, both MatLyLu and HMLL cells were transfected with dominant-negative form of HIF-1α (DNHIF-1α). The Matrigel invasion activity induced by chronic hypoxia was significantly attenuated by DNHIF-1α. These results suggest that signaling pathways leading to hypoxic response may be differentially regulated in chronic hypoxic cells and acute hypoxic cells. Chronic hypoxia may play a greater role than acute hypoxia in promoting the aggressive phenotype of tumor cells. This observation mimics the clinical scenario where tumor cells following treatment with radiation are subjected to hypoxic conditions. The reemergence of tumor following treatment usually results in tumor cells that are more aggressive and metastatic.  相似文献   
79.
80.
Peptidomimetics hold a great promise as therapeutic agents for neurodegenerative disorders. We previously described a Nerve Growth Factor (NGF)-like peptide, now named BB14, which was found to act as a strong TrkA agonist and to be effective in the sciatic nerve injury model of neuropathic pain. In this report we present the effects of BB14 in reducing reactive astrocytosis and reverting neuroplastic changes of the glutamate/GABAergic circuitry in the lumbar spinal cord following spared nerve injury (SNI) of the sciatic nerve. Immunohistochemical analysis of spinal cord sections revealed that SNI was associated with increased microglial (Iba1) and astrocytic (GFAP) responses, indicative of reactive gliosis. These changes were paralleled by (i) decreased glial aminoacid transporters (GLT1 and GlyT1) and increased levels of (ii) neuronal glutamate transporter EAAC1, (iii) neuronal vesicular GABA transporter (vGAT) and (iv) the GABAergic neuron marker GAD65/67. A remarkable increase of the Glutamate/GABA ratio and the reduction of glutathione (GSH) levels were also indicative of modifications of glial function in neuroprotection. All these molecular changes were found to be linked to an alteration of endogenous NGF metabolism, as demonstrated by decreased levels of mature NGF, increase of proNGF and increased activity of NGF-degrading methallo-proteinases (MMPs). Biochemical alterations and SNI-related neuropathic behavior, characterized by allodynia and hyperalgesia, were reversed by 7-days i.t. administration of the NGF-like peptide BB14, as well as by increasing endogenous NGF levels by i.t. infusion of GM6001, a MMPs inhibitor. All together, while confirming the correlation between reactive astrogliosis and perturbation of synaptic circuitry in the SNI model of peripheral nerve injury, these data strongly support the beneficial effect of BB14 in reducing reactive astrogliosis and restoring synaptic homeostasis under pathological conditions linked to alteration of NGF availability and signaling, thereby suggesting a potential role of BB14 as a therapeutic agent.  相似文献   
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