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Yun-Hee Rhee Phil-Sang Chung Sung-Hoon Kim Jin Chul Ahn 《Biochemical and biophysical research communications》2014
Anethole has been known to have chemopreventive activities as a suppressor of the incidence and multiplicity of both invasive and noninvasive carcinomas. The goal of this study was to understand the anti-metastatic effect of anethole through C-X-C chemokine receptor type 4 (CXCR4)/tumor suppressor phosphatase and tensin homologue (PTEN) axis in DU145 prostate cancer cells. Anethole reduced both of the RNA level and the protein level of CXCR4 in a dose-dependent manner without cytotoxicity. Anethole also reduced the expression of CXCR4 and prolonged the expression of PTEN in DU145 prostate cancers. The phosphorylation of AKT and phosphatidylinositol-3kinase (PI3K) were decreased with anethole. The inhibition metastatic effect of anethole was arisen from down-regulating CXCR4 and up-regulating PTEN. Morphologically, anethole significantly inhibited the invasion of DU145 cell and down-regulated the activities of matrix-metalloproteinase (MMPs) in a dose-dependent manner. However, anethole didnot decrease the phosphorylation of PI3K and AKT while PTEN was silenced. Furthermore, the CXCR4 inhibition of anethole was not caused to proteasomal or lysosomal of CXCR4. 相似文献
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Merkel cell tumor is an unusual, aggressive malignancy of skin that has been considered to be derived from cutaneous Merkel cells. We are reporting a case of Merkel cell tumor overlying the left scapula with metastases to the thoracic spine and pleura. The tumor was found incidentally in a 23-year-old pregnant black woman. The tumor recurred locally 5 months after initial wide excision. Subsequently, a second wide excision of the recurrent tumor with ipsilateral axillary dissection was performed. The course of the disease was complicated by local recurrence and formation of distant metastases to pleura and spine. At the end-stage of the disease, the patient was found to have a cardiac murmur, and echocardiography revealed a mass in the anterior wall of the right ventricle that was suspicious for a metastatic lesion. The patient expired from extensive distant metastases 23 months after diagnosis. 相似文献
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Soo Min Han Byungjin Hwang Tae-gun Park Do-Il Kim Moo-Yong Rhee Byoung-Kwon Lee Young Keun Ahn Byung Ryul Cho Jeongtaek Woo Seung-Ho Hur Jin-Ok Jeong Sungha Park Yangsoo Jang Min Goo Lee Duhee Bang Ji Hyun Lee Sang-Hak Lee 《PloS one》2015,10(5)
Familial hypercholesterolemia (FH) is a genetic disorder with an increased risk of early-onset coronary artery disease. Although some clinically diagnosed FH cases are caused by mutations in LDLR, APOB, or PCSK9, mutation detection rates and profiles can vary across ethnic groups. In this study, we aimed to provide insight into the spectrum of FH-causing mutations in Koreans. Among 136 patients referred for FH, 69 who met Simon Broome criteria with definite family history were enrolled. By whole-exome sequencing (WES) analysis, we confirmed that the 3 known FH-related genes accounted for genetic causes in 23 patients (33.3%). A substantial portion of the mutations (19 of 23 patients, 82.6%) resulted from 17 mutations and 2 copy number deletions in LDLR gene. Two mutations each in the APOB and PCSK9 genes were verified. Of these anomalies, two frameshift deletions in LDLR and one mutation in PCSK9 were identified as novel causative mutations. In particular, one novel mutation and copy number deletion were validated by co-segregation in their relatives. This study confirmed the utility of genetic diagnosis of FH through WES. 相似文献
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Kyung Hwan Jung Mahn Hoon Park Hong Mo Moon Joon Shick Rhee 《Biotechnology letters》1991,13(12):857-862
Summary In the hepatitis B surface antigen (HBsAg)-producing recombinant yeast culture medium, the supply of Bacto-yeast nitrogen base without amino acids was found to be inadequate due to the lack of the several kinds of vitamins and trace elements. When the culture medium for this recombinant yeast was supplemented with sufficient vitamins and trace elements, its growth, HBsAg production and the stability of plasmid were improved. 相似文献
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Lee J Hong SW Chae SW Kim DH Choi JH Bae JC Park SE Rhee EJ Park CY Oh KW Park SW Kim SW Lee WY 《PloS one》2012,7(2):e31394
The effects of exendin-4 on Sirt1 expression as a mechanism of reducing fatty liver have not been previously reported. Therefore, we investigated whether the beneficial effects of exendin-4 treatment on fatty liver are mediated via Sirt1 in high-fat (HF) diet-induced obese C57BL/6J mice and related cell culture models. Exendin-4 treatment decreased body weight, serum free fatty acid (FA), and triglyceride levels in HF-induced obese C57BL/6J mice. Histological analysis showed that exendin-4 reversed HF-induced hepatic accumulation of lipids and inflammation. Exendin-4 treatment increased mRNA and protein expression of Sirt1 and its downstream factor, AMPK, in vivo and also induced genes associated with FA oxidation and glucose metabolism. In addition, a significant increase in the hepatic expression of Lkb1 and Nampt mRNA was observed in exendin-4-treated groups. We also observed increased expression of phospho-Foxo1 and GLUT2, which are involved in hepatic glucose metabolism. In HepG2 and Huh7 cells, mRNA and protein expressions of GLP-1R were increased by exendin-4 treatment in a dose-dependent manner. Exendin-4 enhanced protein expression of Sirt1 and phospho-AMPKα in HepG2 cells treated with 0.4 mM palmitic acid. We also found that Sirt1 was an upstream regulator of AMPK in hepatocytes. A novel finding of this study was the observation that expression of GLP-1R is proportional to exendin-4 concentration and exendin-4 could attenuate fatty liver through activation of Sirt1. 相似文献
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Use of Pseudomonas putida EstA as an Anchoring Motif for Display of a Periplasmic Enzyme on the Surface of Escherichia coli 总被引:1,自引:0,他引:1 下载免费PDF全文
The functional expression of proteins on the surface of bacteria has proven important for numerous biotechnological applications. In this report, we investigated the N-terminal fusion display of the periplasmic enzyme β-lactamase (Bla) on the surface of Escherichia coli by using the translocator domain of the Pseudomonas putida outer membrane esterase (EstA), which is a member of the lipolytic autotransporter enzymes. To find out the transport function of a C-terminal domain of EstA, we generated a set of Bla-EstA fusion proteins containing N-terminally truncated derivatives of the EstA C-terminal domain. The surface exposure of the Bla moiety was verified by whole-cell immunoblots, protease accessibility, and fluorescence-activated cell sorting. The investigation of growth kinetics and host cell viability showed that the presence of the EstA translocator domain in the outer membrane neither inhibits cell growth nor affects cell viability. Furthermore, the surface-exposed Bla moiety was shown to be enzymatically active. These results demonstrate for the first time that the translocator domain of a lipolytic autotransporter enzyme is an effective anchoring motif for the functional display of heterologous passenger protein on the surface of E. coli. This investigation also provides a possible topological model of the EstA translocator domain, which might serve as a basis for the construction of fusion proteins containing heterologous passenger domains. 相似文献