Novel signaling axis for ROS generation during K-Ras-induced cellular transformation

Park, M-T,Kim, M-J,Suh, Y,Kim, R-K,Kim, H,Lim, E-J,Yoo, K-C,Lee, G-H,Kim, Y-H,Hwang, S-G,Yi, J-M,Lee, S-J Macmillan Publishers Limited 2014 CELL DEATH AND DIFFERENTIATION Vol.21 No.8

Reactive oxygen species (ROS) are well known to be involved in oncogene-mediated cellular transformation. However, the regulatory mechanisms underlying ROS generation in oncogene-transformed cells are unclear. In the present study, we found that oncogenic K-Ras induces ROS generation through activation of NADPH oxidase 1 (NOX1), which is a critical regulator for the K-Ras-induced cellular transformation. NOX1 was activated by K-Ras-dependent translocation of p47<SUP>phox</SUP>, a subunit of NOX1 to plasma membrane. Of note, PKCδ, when it was activated by PDPK1, directly bound to the SH3-N domain of p47<SUP>phox</SUP> and catalyzed the phosphorylation on Ser348 and Ser473 residues of p47<SUP>phox</SUP> C-terminal in a K-Ras-dependent manner, finally leading to its membrane translocation. Notably, oncogenic K-Ras activated all MAPKs (JNK, ERK and p38); however, only p38 was involved in p47<SUP>phox</SUP>-NOX1-dependent ROS generation and consequent transformation. Importantly, K-Ras-induced activation of p38 led to an activation of PDPK1, which then signals through PKCδ, p47<SUP>phox</SUP> and NOX1. In agreement with the mechanism, inhibition of p38, PDPK1, PKCδ, p47<SUP>phox</SUP> or NOX1 effectively blocked K-Ras-induced ROS generation, anchorage-independent colony formation and tumor formation. Taken together, our findings demonstrated that oncogenic K-Ras activates the signaling cascade p38/PDPK1/PKCδ/p47<SUP>phox</SUP>/NOX1 for ROS generation and consequent malignant cellular transformation.

한국인 Long Term Non Progressors로부터 분리된 HIV-1 env 및 nef 유전자와 이들의 면역 유전학적 특성 분석에 의한 질병진전 요인 규명

이주실,강춘,김성순,박근용,고운영,기미경,최병선,남정구,서순덕,이성래,구본기,박혜경,도경미,김태규,최희백,조현일,김요숙,김지영,이해정,안수진 국립보건연구원 1999 국립보건원보 Vol.36 No.-

A novel chimeric promoter that is highly responsive to hypoxia and metals

Lee, J-Y,Lee, Y-S,Kim, J-M,Kim, K L,Lee, J-S,Jang, H-S,Shin, I-S,Suh, W,Jeon, E-S,Byun, J,Kim, D-K Nature Publishing Group 2006 Gene Therapy Vol.13 No.10

To develop a potent hypoxia-inducible promoter, we evaluated the usefulness of chimeric combinations of the (Egr-1)-binding site (EBS) from the Egr-1 gene, the metal-response element (MRE) from the metallothionein gene, and the hypoxia-response element (HRE) from the phosphoglycerate kinase 1 gene. In transient transfection assays, combining three copies of HRE (3 × HRE) with either EBS or MRE significantly increased hypoxia responsiveness. When a three-enhancer combination was tested, the EBS–MRE-3 × HRE (E–M–H) gave a hypoxia induction ratio of 69. The expression induced from E–M–H-pGL3 was 2.4-fold higher than that induced from H-pGL3 and even surpassed the expression from a human cytomegalovirus promoter-driven vector. The high inducibility of E–M–H was confirmed by validation studies in different cells and by expressing other cDNAs. Gel shift assays together with functional overexpression studies suggested that increased levels of hypoxia-inducible factor 1α, metal transcription factor-1 and Egr-1 may be associated with the high inducibility of the E–M–H chimeric promoter. E–M–H was also induced by hypoxia mimetics such as Co<SUP>2+</SUP> and deferoxamine (DFX) and by hydrogen peroxide. Gene expression from the E–M–H was reversible as shown by the reduced expression of the transgene upon removal of inducers such as hypoxia and DFX. In vivo evaluation of the E–M–H in ischemic muscle revealed that erythropoietin secretion and luciferase and LacZ expression were significantly higher in the E–M–H group than in a control or H group. With its high induction capacity and versatile means of modulation, this novel chimeric promoter should find wide application in the treatment of ischemic diseases and cancer.Gene Therapy (2006) 13, 857–868. doi:10.1038/sj.gt.3302728; published online 9 February 2006

Protective effect of albiflorin against oxidative-stress-mediated toxicity in osteoblast-like MC3T3-E1 cells

Suh, K.S.,Choi, E.M.,Lee, Y.S.,Kim, Y.S. Elsevier 2013 Fitoterapia Vol.89 No.-

Albiflorin isolated from Paeoniae Radix was investigated for its ability to protect against antimycin A-induced osteoblast toxicity in the MC3T3-E1 cell line. MC3T3-E1 cells showed significantly reduced viability, increased apoptosis and lactate dehydrogenase release, elevated ROS/RNS levels, and decreased mitochondrial function after exposure to antimycin A. Pretreatment with albiflorin reversed the loss of cell viability in antimycin A-treated cultures. Similarly, pretreatment with albiflorin before antimycin A resulted in decreased apoptosis and lactate dehydrogenase release, decreased ROS/RNS levels, and increased mitochondrial function compared to antimycin A-treated cultures. In addition, albiflorin increased the mineralization reduced by antimycin A. Albiflorin reduced antimycin A-induced mitochondrial cytochrome c loss and cardiolipin peroxidation, conferring protection against ROS. These results confirmed the crucial role of cytochrome c and cardiolipin in the underlying mechanistic action of albiflorin. Therefore, the results suggest that albiflorin enhances mitochondrial function to suppress antimycin A-induced oxidative damage via the preservation of cytochrome c and cardiolipin. All of these data indicate that albiflorin may reduce or prevent osteoblast degeneration in osteoporosis.

Catalytic Growth and Optical Characterization of ZnO Nanowire on Silicon and Sapphire

J. Y. Kim,E.-K. Suh,H. W. Shim,K. S. Nahm,S. H. Lee,T. Y. Kim,Y. H. Mo 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.44 No.1

We successfully synthesized large-scale ZnO nanowires by using a simple thermal evaporation method. ZnO nanowires with high density were synthesized on silicon and sapphire substrates at low temperature (500 C) for 1 h in a vertical chemical vapor deposition (CVD) reactor. We obtained nanowires with a cone-like structure. The diameters of the ZnO nanowires ranged from 20 to 150 nm and the lengths from 2 to 3 m. Some nanowires had tips which were bent. Moreover, the ZnO nanowires grown on sapphire substrates were well aligned. Typically, sapphire has a good lattice match with ZnO. The photoluminescence spectra exhibited an ultraviolet (UV) emission at 3.3 eV (370 nm) and a weak green emission at 2.4 eV (520 nm) at room temperature. Also, we observed Raman peaks at 438 cm..1 (E2 mode) and 578 cm..1 (E1 (LO) mode), which indicated high-quality ZnO nanowires. After rapid thermal annealing (RTA) at 450 C for 60 s, the peaks of the Raman spectra became sharper and stronger; the intensity of the green emission and the full width at half maximum of the UV emission peak decreased. These results indicate that the defects in the ZnO nanowires are reduced and that the crystal quality of ZnO nanowires is improved through the RTA process.

Effects of Estradiol on the Paracrine Regulator Expression of In Vitro Maturated Murine Ovarian Follicles

Kim, Y. J.,Park, K. E.,Kim, Y. Y.,Kim, H.,Ku, S. Y.,Suh, C. S.,Kim, S. H.,Choi, Y. M. 한국조직공학과 재생의학회 2017 조직공학과 재생의학 Vol.13 No.6

<P>The preservation of female germ cells is important in the individuals with ovarian dysfunction and failure. For this purpose, ovarian follicle in vitro maturation (OFIVM) is an important technology for the retrieval of mature oocytes. In the in vivo follicular development, paracrine factors such as angiotensin (AT) and anti-Mullerian hormone (AMH) play important roles. We attempted to add estrogen during the OFIVM and to assess their expression on the follicular cells. The ovaries and pre-antral follicles were collected from 13-day C57BL/6 mice and cultured in vitro with estradiol (E-2) treatment for up to two weeks. In the whole ovaries, the expression of AT II was decreased and the expression of AMH was similar between control and E-2-treated ovaries after in vitro culture. Although there was no difference in the survival, ovulation, maturation and fertilization rates between control and E-2-treated groups, the expression of AT II in the follicular cells was down-regulated after E-2 treatment at mRNA level, and AMH showed similar expression. In conclusion, adding E-2 in OFIVM may regulate paracrine factors and their receptors that are related to follicular development. Further investigations are necessary to elucidate the roles of various sex hormones in the regulation of AT and AMH expression during the OFIVM.</P>

p34 is a novel regulator of the oncogenic behavior of NEDD4-1 and PTEN

Hong, S-W,Moon, J-H,Kim, J-S,Shin, J-S,Jung, K-A,Lee, W-K,Jeong, S-Y,Hwang, J J,Lee, S-J,Suh, Y-A,Kim, I,Nam, K-Y,Han, S,Kim, J E,Kim, K-p,Hong, Y S,Lee, J-L,Lee, W-J,Choi, E K,Lee, J S,Jin, D-H,Kim, Macmillan Publishers Limited 2014 CELL DEATH AND DIFFERENTIATION Vol.21 No.1

PTEN is one of the most frequently mutated or deleted tumor suppressors in human cancers. NEDD4-1 was recently identified as the E3 ubiquitin ligase for PTEN; however, a number of important questions remain regarding the role of ubiquitination in regulating PTEN function and the mechanisms by which PTEN ubiquitination is regulated. In the present study, we demonstrated that p34, which was identified as a binding partner of NEDD4-1, controls PTEN ubiquitination by regulating NEDD4-1 protein stability. p34 interacts with the WW1 domain of NEDD4-1, an interaction that enhances NEDD4-1 stability. Expression of p34 promotes PTEN poly-ubiquitination, leading to PTEN protein degradation, whereas p34 knockdown results in PTEN mono-ubiquitination. Notably, an inverse correlation between PTEN and p34/NEDD4-1 levels was confirmed in tumor samples from colon cancer patients. Thus, p34 acts as a key regulator of the oncogenic behavior of NEDD4-1 and PTEN.

Z-map으로 표현된 수직 벽면을 가진 금형에서의 접촉처리법과 클로버형 컵 디프드로잉 공정의 해석에의 응용

서의권,박정환,심현보 한국공작기계학회 1998 한국생산제조학회지 Vol.7 No.5

The Z-map model which is quite similar to the non-parametric patch is widely used to describe the shape of a surface because of its simplicity. Despite the inherent advantage of z-map model, it has drawbacks that there exists difficulty in expressing the vertical walls and its related contact treatment method. In the region of vertical walls, there is a convergence problem in searching the contact point. In this study a contact point finding scheme is presented, based on the z value of vertical-wall-included clover shape cup deep drawing process is analyzed and the results are compared with the experimental results. The effects of the Z-map grid distances and the interpolations of the inside Z-map value are also discussed.

하악골과두부에 전이된 유두상 갑상선암의 치험례

서창호,차인호,김진권,이의웅,김형준,이병인 大韓顎顔面成形再建外科學會 1995 Maxillofacial Plastic Reconstructive Surgery Vol.17 No.4

Thyroid carcinomas are usually classified as papillary thyroid carcinoma, follicular thyroid carcinoma, medullary thyroid carcinoma and anaplastic thyroid carcinoma. Among the thyroid carcinomas, the incidence of medullary and anaplastic thyroid carcinoma is low, but the rate of lymph node & distant metastasis from them are more common compared to other types. Follicular thyroid carcinoma has a low rate of lymph node metastasis as 10% and has a high occurrence of hematogenous metastasis to lung, bone, brain and liver. Papillary thyroid carcinoma accounts for 60∼70% of whole thyroid carcinomas and the cervical lymph node metastasis is 21∼81% including micrometastasis, but the distant metastasis is rare. In the case of bone metastasis, follicular type reveals most frequent, and the rate is about 5%, and more likely to be found on vertebra, pelvis, ribs, femur, and skull. The clinical symptoms of bone metastasis are pain, swelling, pathological fracture and radiologically osteolytic lesions can be observed. But distant metastasis of papillary thyroid carcinoma is very rare and especially, bone metastasis has hardly been reported. The treatment modalities of metastatic thyroid carcinoma to mandible are known as follows : thyroidectomy to treat primary site, resection of the affected site of mandible, external beam radiotherapy and radioiodine therapy etc.

Concurrent delivery of GM-CSF and B7-1 using an oncolytic adenovirus elicits potent antitumor effect

Choi, K-J,Kim, J-H,Lee, Y-S,Kim, J,Suh, B-S,Kim, H,Cho, S,Sohn, J-H,Kim, G E,Yun, C-O Nature Publishing Group 2006 Gene therapy Vol.13 No.13

Oncolytic adenoviral vectors are currently being developed as biologic anticancer agents. Coupling the lytic function of an oncolytic adenovirus (Ad) with its ability as a transgene delivery system represents a powerful extension of this methodology. A clear advantage is the amplification of a therapeutic gene, as replicating vectors would be able to infect and deliver the gene of interest to neighboring cells. Granulocyte–macrophage colony-stimulating factor (GM-CSF) is one of the most potent stimulators of a specific and long-lasting antitumor immunity and its important role in the maturation of antigen-presenting cells to induce T-cell activation has been well documented. Similarly, the B7 family has also been shown to play an integral role in mediating an antitumor response. Most tumor cells, however, lack the expression of these costimulatory molecules on their surface, thus escaping immune system recognition. To increase the antitumor effect of an oncolytic Ad, we have generated an E1B 55 kDa-deleted oncolytic adenoviral vector, YKL-GB, that expresses both GM-CSF and B7-1. The therapeutic efficacy of YKL-GB Ad was evaluated in immunocompetent mice bearing murine melanoma B16-F10 tumors. Significant inhibition of tumor growth was seen in mice treated with YKL-GB compared to those treated with the analogous vector, YKL-1. Moreover, YKL-GB oncolytic Ad demonstrated enhanced antitumor activity and higher incidences of tumor regression compared to a replication-incompetent Ad, dl-GB, which coexpresses GM-CSF and B7-1. Localized GM-CSF and B7-1 gene transfer also conferred long-lasting immunity against a tumor re-challenge. To establish that the observed antitumor effect is associated with the generation of a tumor-specific immune response, we carried out interferon-γ enzyme-linked immune spot assay. We observed that YKL-GB induced significantly higher immune cell activation than YKL-1. Furthermore, immunohistochemical studies demonstrated robust dendritic cells and CD4<SUP>+</SUP>/CD8<SUP>+</SUP> T-cell infiltration in these mice compared to the YKL-1-treated groups. In agreement with these results, splenocytes from tumor-bearing mice treated with YKL-GB expressed high levels of the costimulatory and activation molecules. These findings demonstrate the effectiveness of enhancing the immune response against tumors with an oncolytic Ad expressing both GM-CSF and B7-1 and provide a potential therapeutic strategy for the management of neoplasia.Gene Therapy (2006) 13, 1010–1020. doi:10.1038/sj.gt.3302759; published online 9 March 2006