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Objective: This study explored the protective effects of the microRNA-126 (miR-126)- mediated PI3K/Akt/eNOS signaling pathway on human cardiac microvascular endothelial cells (HCMECs) against hypoxia/reoxygenation (H/R)-induced injury and the inflammatory response. Methods: Untreated HCMECs were selected for the control group. After H/R treatment and cell transfection, the HCMECs were assigned to the H/R, miR-126 mimic, mimicnegative control (NC), miR-126 inhibitor, inhibitor-NC, wortmannin (an inhibitor of PI3K) and miR-126 mimic + wortmannin groups. Super oxide dismutase (SOD), nitric oxide (NO), vascular endothelial growth factor (VEGF) and reactive oxygen species (ROS) were measured utilizing commercial kits. Quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) were performed to detect miR-126 expression and the mRNA and protein expression of inflammatory factors. Western blotting was used to determine the expression of key members in the PI3K/Akt/eNOS signaling pathway. ACCK- 8 assay and flow cytometry were employed to examine cell proliferation and apoptosis, respectively. The angiogenic ability in each group was detected by the lumen formation test. Results: Compared to the control group, p/t-PI3K, p/t-Akt and p/t-eNOS expression, NO, VEGF and SOD levels, cell proliferation and in vitro lumen formation ability were decreased, while the ROS content, interleukin (IL)-6, IL-10 and tumor necrosis factor (TNF)-α expression and cell apoptosis were significantly increased in the H/R, mimic-NC, miR-126 inhibitor, inhibitor- NC, wortmannin and miR-126 mimic + wortmannin groups. Additionally, in comparison with the H/R group, the miR-126 mimic group had elevated p/t-PI3K, p/t-Akt and p/t-eNOS expression, increased NO, VEGF and SOD contents, and strengthened cell proliferation and lumen formation abilities but also exhibited decreased ROS content, reduced IL-6, IL-10 and TNF-α expressions, and weakened cell apoptosis, while the miR-126 inhibitor and wortmannin group exhibited the opposite results. Furthermore, decreased p/t-PI3K, p/t-Akt and p/t-eNOS expressions, decreased NO, VEGF and SOD contents, cell proliferation and lumen formation abilities, as well as increased ROS content, increased IL-6, IL-10 and TNF-α expression, and increased cell apoptosis were observed in the miR-126 mimic + wortmannin group compared to themiR-126 mimic group. Conclusions: These findings indicated that miR-126 protects HCMECs from H/R-induced injury and inflammatory response by activating the PI3K/Akt/ eNOS signaling pathway. [ABSTRACT FROM AUTHOR]

Background/Aims: Growth arrest-specific protein 6 (Gas6) is a cytokine that can be synthesized by a variety of cell types and secreted into the extracellular matrix. Previous studies have confirmed that Gas6 is involved in certain pathophysiological processes of the cardiovascular system through binding to its receptor, Axl. In the present study, we investigated the role of Gas6 in cellular senescence and explored the mechanisms underlying its activity. Methods: We used vascular smooth muscle cells (VSMCs) to create two cellular senescence models, one for replicative senescence (RS) and one for induced senescence (IS), to test the hypothesis that Gas6 delays senescence. Results: Gas6-treated cells appear relatively younger compared with non-Gas6-treated cells. In particular, Gas6-treated cells displayed decreased staining for SA-β-Gal, fewer G1 phase cells, and decreased levels of p16INK4a and p21Cip1 expression; conversely, Gas6-treated cells displayed more S phase cells and significantly increased proliferation indexes. Furthermore, in both the IS and RS models with Gas6 treatment, the levels of PI3K, p-Akt, and p-FoxO3a decreased following Axl inhibition by R428; similarly, the levels of p-Akt and p-FoxO3a also decreased following PI3K inhibition by LY294002. Conclusion: Gas6/Axl signaling is essential for delaying the cellular senescence process regulated by the PI3K/Akt/FoxO signaling pathway. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Mantle cell lymphoma (MCL) remains incurable and new treatments are needed, especially in the relapsed/refractory setting. We therefore investigated the effects of carfilzomib, a novel, long-acting, second-generation proteasome inhibitor, in MCL cells. Eight established MCL cell lines and freshly isolated primary MCL cells were treated with carfilzomib. Cell proliferation was assessed by a 3H-thymidine incorporation assay. Cell apoptosis was evaluated by flow cytometry with annexin V and propidium iodide. Electrophoresis mobility shift (EMSA), Western blot, and luciferase assays were used to analyze NF-κB activation and related signaling proteins. Carfilzomib inhibited growth and induced apoptosis in both established MCL cell lines and freshly isolated primary MCL cells in a dose-dependent manner. In contrast, carfilzomib was less toxic to normal peripheral blood mononuclear cells from healthy individuals. The carfilzomib-induced apoptosis of MCL cells occurred in a caspase-dependent manner through both intrinsic and extrinsic caspase pathways. In addition, carfilzomib inhibited constitutive activation of the NF-κB signaling cascade, both in MCL cell lines and primary MCL cells, by completely blocking the phosphorylation of IκBα. Our results demonstrate that carfilzomib can induce growth arrest and apoptosis in MCL cells and that the mechanism may involve the NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Background/Aims: Colorectal cancer (CRC) is the third most common type of cancer worldwide. Sprouty proteins are modulators of mitogeninduced signal transduction processes and therefore can influence the process of cancerogenesis. The encoded protein of Sprouty homolog 4 (SPRY4) is associated with various human cancers. However, its biological role and clinical significance in CRC development and progression are unknown. Methods: The aim of this study was to evaluate the expression and biological role of SPRY4 in colorectal cancer. qRT-PCR was performed to investigate the expression of SPRY4 in tumor tissues and corresponding non tumor colorectal tissues from 70 patients. The effect of SPRY4 on proliferation was evaluated by MTT and colony formation assays. CRC cells transfected with SPRY4 were injected into nude mice to study the effect of SPRY4 on tumorigenesis in vivo. Results: The lower expression of SPRY4 was remarkably correlated with deep tumor invasion and advanced TNM stage. Multivariate analyses revealed that SPRY4 expression served as an independent predictor for overall survival. Using 5-aza treatment, we also observed that SPRY4 expression can be affected by DNA methylation. Further experiments revealed that overexpressed SPRY4 significantly inhibited CRC cell proliferation both in vitro and in vivo. Conclusion: Our study demonstrated that SPRY4 is involved in the development and progression of colorectal cancer by regulating cell proliferation and shows that SPRY4 may be a potential diagnostic and prognostic target in patients with colorectal cancer. [ABSTRACT FROM AUTHOR]

We investigated the anti-tumor efficiency of sonodynamic therapy (SDT) on human tongue squamous carcinoma SAS cell line using low intensity ultrasound (LIU) of 0.6 and 0.8 W/cm2, plus 5-aminolevulinic acid (ALA). Xenograft in vivo experiments using Balb/ca nude mice and MTT assays in vitro showed that ALA-LIU therapy significantly suppressed the proliferation of SAS cells. ALA-LIU therapy markedly enhanced SAS cell apoptosis rate compared to LIU alone. Based on TEM and fluorescence microscopy observations, there are notably morphology changes and seriously swollen mitochondria in xenograft tissues, and ALA-induced PpIX bond strongly to mitochondria of SAS cells. Immunohistochemical staining and western blotting demonstrated upregulation of Bax, cytochrome c and caspase-3, and downregulation of Bcl-2 for both in vivo and in vitro cases after ALA-LIU treatment. Increase of reactive oxygen species (ROS) in the ALA-LIU treatment groups were found using 2, 7-dichlorofluorescin diacetate (DCFH-DA) staining. Administration of the ROS scavenger, N-acetylcysteine (NAC), suppressed ALA-LIU-induced apoptosis and the expression of mitochondria apoptosis-related proteins, which confirmed that the ALA-LIU induced SAS cell apoptosis is through the generation of ROS. The process initially damaged mitochondria, activated pro-apoptotic factors Bax and cytochrome c and supressed the anti-apoptotic factor Bcl-2, activated caspase-3 to executed apoptosis through mitochondrial signaling pathway. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]