Background and purpose: Although the main therapeutic effect of angiotensin AT1 receptor antagonists is to decrease blood pressure, they also exert anti-inflammatory effects in the cardiovascular system. However, the underlying mechanisms remain unclear. We investigated the inhibitory effect of AT1 antagonists on the chemokine monocyte chemoattractant protein 1 (MCP-1) and its receptor C-C chemokine receptor 2 (CCR2) in rat monocytes and aortas. Experimental approach: Spontaneous hypertensive rats (SHRs) were treated with the AT1 antagonists losartan or telmisartan for 4 weeks, and Wistar-Kyoto rats (WKYs) were used as normotensive controls. Systolic arterial pressure was measured, and the number of macrophages in the aortic vessel wall was assessed by anti-ED-1 antibody immunolabelling. Key results: Compared with WKYs, SHRs showed significantly increased ED-1 positive macrophages in the aortic wall, which were decreased after high doses of losartan or telmisartan. Low doses of losartan did not improve blood pressure significantly as did the high doses, but markedly decreased macrophage infiltration in the vessel wall. AT1 antagonists, particularly at high doses, improved aortic remodeling in SHR. At the molecular level, AT1 antagonists attenuated the expression of MCP-1 and CCR2 in the aorta and peripheral blood monocytes and lowered the serum level of MCP-1. In addition, Western blotting showed that AT1 antagonists inhibited the phosphorylation of Akt in mouse monocytes. Conclusions and implications: AT1 antagonism inhibited vessel wall inflammation and inhibition of PI3K/Akt may be involved in the modulation of the MCP-1/CCR2 system by AT1 antagonists in SHRs.
Anti-angiogenic therapy has been successfully applied to treat colorectal cancer (CRC). Ginsenoside Rg3, derived from the Chinese herb ginseng, has anti-vascularization effects and can inhibit tumor growth and metastasis, and can sensitize cancer cells to chemotherapy. Therefore, in the present study, we investigated whether Rg3 could be appropriate for CRC treatment. Growth of CRC cells was assessed by an MTT (methyl thiazolyl tetrazolium) assay in vitro and using orthotopic xenograft models in vivo. mRNA expression was evaluated using real-time PCR. Protein levels were tested by western blotting, flow cytometry and immunohistochemistry. Migration was determined using a wound-healing assay. Stemness was further confirmed using a plate clone formation assay. We found that Rg3 repressed the growth and stemness of CRC cells both in vitro and in vivo. Rg3 also impaired the migration of CRC cells in vitro. Rg3 downregulated the expressions of angiogenesis-related genes, and repressed the vascularization of CRC xenografts. In addition, Rg3 strengthened the cytotoxicity of 5-Fluorouracil and oxaliplatin against orthotopic xenografts in vivo. Moreover, Rg3 downregulated the expressions of B7-H1 and B7-H3, high expressions of which were associated with reduced overall survival (OS) of CRC patients. Hence, Rg3 not only repressed the growth and stemness of CRC cells, but could also remodel the tumor microenvironment through repressing angiogenesis and promoting antitumor immunity. Therefore, Rg3 could be a novel therapeutic for the CRC treatment.
Background VEGF/VEGFR2 pathway is the central therapeutic target in anti-angiogenic treatment in multiple cancers. However, little work has been carried out concerning the pro-malignancy functions of VEGFR2 that are independent of its pro-angiogenesis effects in gastric cancer. Here, we demonstrated that VEGFR2 up-regulation in gastric cancer tissues was a prognostic marker for poor disease-free survival and overall survival of gastric cancer patients. Methods Immunohistochemistry was used to detect VEGFR2 and VTN expressions in specimens. Kaplan–Meier curves were constructed for survival analysis. Stably knockdown cell lines and overexpression cell lines were constructed by small interfering RNA and plasmids transfection. Real-time PCR and Western blot were used to confirm the expressions of target genes at both RNA and protein levels. Cell proliferation was measured by using Cell Counting Kit-8 and xenograft models. Microarray and bioinformatic analysis were also performed to identify the relationship between Vitronectin (VTN) and VEGFR2. Results When overexpressed in gastric cancer cells, VEGFR2 increased cellular proliferation and invasion in vitro and tumor formation in xenograft models. By using integrating microarray and bioinformatic analysis, we identifiedVTN as a downstream of VEGFR2 pathway. In gain- and loss-of function analysis in gastric cancer cells, VTN was further verified in consistent with VEGFR2 in expression levels and in regulating cell growth and motility in vitro and in vivo . Moreover, in gastric cancer samples, VTN was as also revealed as a poor prognostic factor. Conclusions Our present findings defined a novel activity for VEGFR2 in promoting tumorogenicity, motility and indicating a poor survival in gastric cancer beyond its known pro-angiogenic effects. Implications Our present findings defined a novel activity for VEGFR2 in promoting tumorogenicity, motility and indicating a poor survival in gastric cancer beyond its known pro-angiogenic effects, which may provide a new and valuable target for design of therapies for intervention and a new cognitive perspective for the anti-angiogenesis therapies. Electronic supplementary material The online version of this article (10.1186/s12885-019-5322-0) contains supplementary material, which is available to authorized users.
The outbreak of a new coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) in China in December 2019 has brought serious challenges to disease prevention and public health. Patients with severe coronavirus disease 2019 (COVID-19) who undergo cardiovascular surgery necessitate extremely high demands from anesthesia personnel, and face high risks of mortality and morbidity. Based on the current understanding of COVID-19 and the clinical characteristics of cardiovascular surgical patients, the authors provide anesthesia management guidelines for cardiovascular surgery along with the prevention and control of COVID-19.
PurposeDespite new developments in cancer therapy, chemotherapy and radiotherapy remain the cornerstone of breast cancer treatment. Therefore, finding ways to reduce the toxicity and increase sensitivity is particularly important. Tumor necrosis factor alpha (TNF-α) exerts multiple functions in cell proliferation, differentiation and apoptosis. In the present study, we investigated whether TNF-α could enhance the effect of chemotherapy and radiotherapy against breast cancer cells.MethodsCell growth was determined by MTT assay in vitro, and by using nude mouse tumor xenograft model in vivo. Cell cycle and apoptosis/necrosis were evaluated by flow cytometry. DNA damage was visualized by phospho-Histone H2A.X staining. mRNA expression was assessed by using real-time PCR. Protein expression was tested by Western blot assay.ResultsTNF-α strengthened the cytotoxicity of docetaxel, 5-FU and cisplatin against breast cancer cells both in vitro and in vivo. TNF-α activated NF-κB pathway and dependently up-regulated expressions of CyclinD1, CyclinD2, CyclinE, CDK2, CDK4 and CDK6, the key regulators participating in G1→S phase transition. As a result, TNF-α drove cells out of quiescent G0/G1 phase, entering vulnerable proliferating phases. Treatment of TNF-α brought more DNA damage after Cs137-irradiation and strengthened G2/M and S phase cell cycle arrest induced by docetaxel and cisplatin respectively. Moreover, the up-regulation of RIP3 (a necroptosis marker) by 5-FU, and the activation of RIP3 by TNF-α, synergistically triggered necroptosis (programmed necrosis). Knockdown of RIP3 attenuated the synergetic effect of TNF-α and 5-FU.ConclusionTNF-α presented radiotherapy- and chemotherapy-sensitizing effects against breast cancer cells.
Preoperative clopidogrel exposure increased bleeding and transfusion requirements in patients receiving on-pump CABG. Tranexamic acid reduced this risk and provided extra protection selectively in the patients with persistent clopidogrel exposure within 7 days before surgery. TRIAL REGISTRATIONL clinicaltrials.gov Identifier: NCT01060163.
Jujuboside B (1) is one of the saponins isolated from the seeds of Zizyphus jujuba var. spinosa, which are used as a well-known traditional medicine for the treatment of insomnia and anxiety in East Asian countries. This is the first study to investigate the antitumor mechanism of 1 in vivo and in vitro. The results showed that 1 induced apoptosis and autophagy in AGS and HCT 116 human cancer cells and also effectively suppressed tumor growth in a nude mouse xenograft model bearing HCT 116 cells. The apoptosis-inducing effect of 1 was characterized by annexin V/propidium iodide staining, sub-G1 phase increase, and caspase-3 activation. Mechanistic studies showed that 1-induced apoptosis is associated with the extrinsic pathway through an increase in FasL and caspase-8 activation. Moreover, 1 activated p38/c-Jun N-terminal kinase (JNK), and the extrinsic pathway-mediated apoptosis was attenuated by both SB202190 (a p38 inhibitor) and SP600125 (a JNK inhibitor). The autophagy-inducing effect was indicated by the formation of cytoplasmic vacuoles and microtubule-associated protein 1 light chain-3 II (LC3-II) conversion. The autophagy inhibitor bafilomycin A1 (BaF) decreased 1-induced cell viability and increased pp38, pJNK, FasL, caspase-8 activation, and caspase-3 activation. Taken together, these results demonstrate that 1 induced protective autophagy to retard extrinsic pathway-mediated apoptosis.
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