TFIIB‐related factor 1 (Brf1) modulates the transcription of RNA Pol III genes (polymerase‐dependent genes). Upregulation of Pol III genes enhances tRNA and 5S RNA production and increases the translational capacity of cells to promote cell transformation and tumor development. However, the significance of Brf1 overexpression in human breast cancer (HBC) remains to be investigated. Here, we investigate whether Brf1 expression is increased in the samples of HBC, and we explore its molecular mechanism and the significance of Brf1 expression in HBC. Two hundred and eighteen samples of HBC were collected to determine Brf1 expression by cytological and molecular biological approaches. We utilized colocalization, coimmunoprecipitation, and chromatin immunoprecipitation methods to explore the interaction of Brf1 with estrogen receptor alpha (ERα). We determined how Brf1 and ERα modulate Pol III genes. The results indicated that Brf1 is overexpressed in most cases of HBC, which is associated with an ER‐positive status. The survival period of the cases with high Brf1 expression is significantly longer than those with low levels of Brf1 after hormone treatment. ERα mediates Brf1 expression. Brf1 and ERα are colocalized in the nucleus. These results indicate an interaction between Brf1 and ERα, which synergistically regulates the transcription of Pol III genes. Inhibition of ERα by its siRNA or tamoxifen reduces cellular levels of Brf1 and Pol III gene expression and decreases the rate of colony formation of breast cancer cells. Together, these studies demonstrate that Brf1 is a good biomarker for the diagnosis and prognosis of HBC. This interaction of Brf1 with ERα and Brf1 itself are potential therapeutic targets for this disease.
Objective: We investigated the molecular mechanism underlying the role of monocyte chemoattractant protein-1 (MCP-1) in the formation and development of human abdominal aortic aneurysm (AAA). Methods: We examined protein expression profiles using a protein array and found that MCP-1 was the most highly expressed protein in AAA tissues compared with normal aortas. To investigate the potential mechanism of MCP-1 involvement in the pathogenesis of AAA, we treated human aortic smooth muscle cells (HASMCs) with human recombinant MCP-1. Results: MCP-1 was the most highly expressed protein in AAA tissues compared with normal aorta; matrix metalloproteinase-9 (MMP-9) expression was also significantly increased. Treatment with MCP-1 significantly increased the expression and activation of MMP-9 and activated the three major mitogen activated protein kinases (MAPKs) extracellular signal regulated kinase (ERK), c-Jun amino terminal kinase (JNK1/2) and p38 MAPK. Furthermore, MCP-1-induced secretion of MMP-9 was inhibited by U0126 (inhibitor of the ERK 1/2 pathway) and SB203580 (inhibitor of the p38 MAPK pathway), but not SP600125 (inhibitor of the JNK1/2 pathway). Conclusion: These data demonstrate that MCP-1 stimulates secretion of MMP-9 directly through the ERK1/2 and p38 MAPK mediated pathways in HASMCs. Thus, inhibition of this molecular mechanism might be a potential therapeutic target in the non-surgical treatment of AAA.
These results suggest angiography is highly valuable for the diagnosis of CBT. Preoperative selective embolization of CBT is an effective and safe adjunct for surgical resection, especially for Shamblin class II and III tumors.
Our study revealed that somatic mutations in exon 17 of the TEK gene were more common in noninherited vascular anomalies than previously reported. Furthermore, such substitutions may shed new light on the molecular etiology, diagnosis, and potential therapeutic targets of vascular anomalies.
Objective: To analyze at one institution the endovascular treatment for aortic arch and proximal thoracic aortic lesions, categorize open arch reconstruction, and make preliminary recommendations based on pathology (dissection vs aneurysm), and anatomical extent of disease. Methods: A retrospective review of aortic arch and descending thoracic aortic lesions managed with endovascular treatment between June 2002 and June 2007.Results: Thirty-four patients received endovascular repair for aortic dissection (n ؍ 28) and aneurysm (n ؍ 6). Open supra-aortic transposition or debranching of the great vessels was performed in 14 cases of dissection (50%) and six cases (100%) of aneurysm. In 14 dissections, the entry tear was located in the distal aortic arch, enabling the left subclavian artery to be sealed without reconstruction. The procedures were successful in 33 patients (97.1%); one intraoperative death occurred. Type I endoleaks were found intraoperatively in eight cases. After management with balloon angioplasty and by extending the stent implantation, the endoleaks resolved in four cases and decreased in four cases. One patient with Stanford type A dissection died from an unknown cause 3 months after treatment. The overall survival rate was 94.1% (32/34), and all bypass grafts remained patent during the follow-up period. Conclusions: Endovascular stent grafting is a safe and effective method for the treatment of aortic arch lesions. Transposition of the supra-aortic great vessels can be effectively combined with endovascular stent grafting to ensure both cerebral blood supply and enough landing area for the stent graft. ( J Vasc Surg 2008;48:64-8.)The conventional method for open aortic arch replacement using a prosthetic graft to reconstruct all three great vessels is often accompanied by complications, significant morbidity, and high mortality. 1-4 Although endovascular stent grafting has greatly enhanced the progress of endovascular repair of lesions originating from and confined to the descending aorta and abdominal aorta, 5-9 the endovascular treatment of aortic arch lesions is still very difficult because it is necessary to reserve or reconstruct one or more of the supra-aortic great vessels. Thus, it is essential to find a safe and effective method for preserving the blood supply to the brain before endovascular repair of aortic arch lesions.This retrospective analysis was designed to review the endovascular treatment of aortic arch and proximal aortic pathology, categorize open arch reconstruction, and make preliminary recommendations based on pathology (dissection vs aneurysm) and anatomical extent of disease. Extent of open arch revascularization was examined in relation to disease presentation (dissection vs aneurysm) and anatomic extent, and categorized into three groups: (1) ascending aorta (AO) based in-situ reconstruction; (2) extra-anatomic reconstruction (carotid to carotid or carotid to subclavian); and (3) no open debranching.
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