Urinary Proteome Profile Predictive of Disease Activity in Rheumatoid Arthritis

Kang, Min Jueng,Park, Yune-Jung,You, Sungyong,Yoo, Seung-Ah,Choi, Susanna,Kim, Dong-Ho,Cho, Chul-Soo,Yi, Eugene C.,Hwang, Daehee,Kim, Wan-Uk American Chemical Society 2014 JOURNAL OF PROTEOME RESEARCH Vol.13 No.11

<P>Current serum biomarkers for rheumatoid arthritis (RA) are not highly sensitive or specific to changes of disease activities. Thus, other complementary biomarkers have been needed to improve assessment of RA activities. In many diseases, urine has been studied as a window to provide complementary information to serum measures. Here, we conducted quantitative urinary proteome profiling using liquid chromatography–tandem mass spectrometry (LC–MS/MS) and identified 134 differentially expressed proteins (DEPs) between RA and osteoarthritis (OA) urine samples. By integrating the DEPs with gene expression profiles in joints and mononuclear cells, we initially selected 12 biomarker candidates related to joint pathology and then tested their altered expression in independent RA and OA samples using enzyme-linked immunosorbent assay. Of the initial candidates, we selected four DEPs as final candidates that were abundant in RA patients and consistent with those observed in LC–MS/MS analysis. Among them, we further focused on urinary soluble CD14 (sCD14) and examined its diagnostic value and association with disease activity. Urinary sCD14 had a diagnostic value comparable to conventional serum measures and an even higher predictive power for disease activity when combined with serum C-reactive protein. Thus, our urinary proteome provides a diagnostic window complementary to current serum parameters for the disease activity of RA.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jprobs/2014/jprobs.2014.13.issue-11/pr500467d/production/images/medium/pr-2014-00467d_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/pr500467d'>ACS Electronic Supporting Info</A></P>

O-GlcNAcylation of SMAD4 and its role in TGF-β Signaling

Yeon Jung Kim,Min Jueng Kang,Min Jueng Kang,Tae Hyun Kweon,Yun Soo Park,Suena Ji,Won Hg Yang,Eugene C. Yi,Jin Won Cho 한국당과학회 2021 한국당과학회 학술대회 Vol.2021 No.01

Post-translational modification of OCT4 in breast cancer tumorigenesis

Cho, Yunhee,Kang, Hyeok Gu,Kim, Seok-Jun,Lee, Seul,Jee, Sujin,Ahn, Sung Gwe,Kang, Min Jueng,Song, Joon Seon,Chung, Joon-Yong,Yi, Eugene C.,Chun, Kyung-Hee Nature Publishing Group 2018 CELL DEATH AND DIFFERENTIATION Vol. No.

<P>Recurrence and drug resistance of breast cancer are still the main reasons for breast cancer-associated deaths. Cancer stem cell (CSC) model has been proposed as a hypothesis for the lethality of breast cancer. Molecular mechanisms underlying CSC maintenance are still unclear. In this study, we generated mammospheres derived from breast cancer MDA-MB231 cells and MCF7 cells to enrich CSCs and performed DNA microarray analysis. We found that the expression of carboxy terminus of HSP70-interacting protein (CHIP) E3 ubiquitin ligase was significantly downregulated in breast CSCs. CHIP depletion increased mammosphere formation, whereas CHIP overexpression reversed this effect. We identified interactomes by mass spectrometry and detected CHIP directly interacted with OCT4, a stemness factor. CHIP overexpression decreased OCT4 stability through proteasomal degradation. CHIP induced OCT4 ubiquitination, whereas H260Q, a catalytic CHIP mutant, did not. Interestingly, we determined that OCT4 was ubiquitinated at lysine 284, and CHIP overexpression did not degrade K284R mutant OCT4. CHIP overexpression decreased the proliferation and side population of breast cancer cells, but these were not occurred in K284R mutant OCT4 overexpressed cells. Only 1000 cells showing CHIP depletion or OCT4 overexpression sufficiently generated breast tumors and lung metastases in xenografted mice. Ubiquitination-defective mutant of OCT4(K284R) overexpressed cells drastically generated tumor burdens in mice. Patients with breast cancer who showed low CHIP expression had poor survival probability. Taken together, we suggest that CHIP-induced OCT4 ubiquitination is important in breast CSCs. Regulation of CHIP expression and OCT4 protein stability is a considerable approach for breast cancer therapy.</P>

Apolipoprotein B binds to enolase-1 and aggravates inflammation in rheumatoid arthritis

Lee, Joo Youn,Kang, Min Jueng,Choi, Ji Yong,Park, Ji Soo,Park, Jin Kyun,Lee, Eun Young,Lee, Eun Bong,Pap, Thomas,Yi, Eugene C,Song, Yeong Wook H. K. Lewis 2018 Annals of the rheumatic diseases Vol. No.

<P>Conclusions A key component of atherogenic lipids, apoB, aggravated arthritis by potentiating the inflammatory response via its interaction with ENO1 expressed on the surface of immune cells. This suggests a novel mechanism by which lipid metabolism regulates chronic inflammation in RA.</P>

0-GlcNAc modification of X -linked inhibitor of apoptosis regulates its E3 ubiquitin ligase activity towards 0-GlcNAc transferase and cancer cell growth

Hyeon Gyu Seo,Han Byeol Kim,Min Jueng Kang,Ji Young Yoon,Tae Hyun Kweon,Yun Soo Park,Jingu Kang,Jinwoo Jung,Eugene C. Yi,Tae Ho Lee,Jin Won Cho 한국당과학회 2018 한국당과학회 학술대회 Vol.2018 No.07

X -linked inhibitor of apoptosis (XIAP), an inhibitor of apoptotic cell death, has a RING domain and functions as an E3 ligase, catalysing the ubiquitination of various substrates such as apoptosis-inducing factor, TGF- [3-activated kinase 1, and MEK kinase 2. Here, we identified 0-linked N-acetylglucosamine ( 0-GlcNAc) transferase ( OGT) as a substrate of XIAP. We showed that OGT catalyses the 0-GlcNAc modification of XIAP at serine 406, and this modification regulates the E3 ligase activity of XIAP towards OGT. Substitution of XIAP Ser406 by alanine decreased its E3 ligase activity toward OGT but not toward other substrates. Stable overexpression of XIAP in HCT116 human colorectal carcinoma cells decreased OGT protein levels and inhibited cancer cell growth and invasion. These results suggest that XIAP requires 0-GlcNAcylation in the regulation of its E3 ligase activity toward OGT, which leads to OGT degradation and the inhibition of cancer cell growth.

Drug repositioning of TANK-binding kinase 1 inhibitor CYT387 as an alternative for the treatment of Gram-negative bacterial sepsis

Lee, Seung Jun,Gharbi, Amal,You, Jueng Soo,Han, Hee Dong,Kang, Tae Heung,Hong, Seong Hwi,Park, Won Sun,Jung, In Duk,Park, Yeong-Min Elsevier 2019 INTERNATIONAL IMMUNOPHARMACOLOGY Vol.73 No.-

<P><B>Abstract</B></P> <P>There is currently no specific drug for the treatment of sepsis and antibiotic administration is considered the best option, despite numerous issues. Therefore, the development of drugs to control the pathogen-induced inflammatory responses associated with sepsis is essential. To address this, our study examined the transcriptomes of lipopolysaccharide (LPS)-induced dendritic cells (DCs), identifying TANK-binding kinase1 (Tbk1) as a key factor involved in the inflammatory response. These data suggested drug repositioning of the Tbk1 inhibitor CYT387, currently used for the treatment of myelofibrosis and some cancers, as a candidate for regulating the LPS-induced inflammatory response. CYT387 also inhibited pro-inflammatory cytokine and surface molecule expression by mature DCs after LPS exposure. These effects correlated with both Akt phosphorylation and IκBα degradation. Finally, CYT387 demonstrated therapeutic effects in LPS-induced endotoxemia and <I>Escherichia coli</I> K1-induced mouse models of sepsis and decreased the expression of pro-inflammatory cytokines. In conclusion, our study suggests that drug repositioning of CYT387 may serve as a potential therapeutic for sepsis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Tbk1 is the most relevant kinase in the “dendritic cell maturation” pathway induced by LPS. </LI> <LI> CYT387 inhibits pro-inflammatory gene expression by interfering with the Akt and NF-κB signaling cascades. </LI> <LI> CYT387 prevents organ dysfunction in <I>E. coli</I> K1-induced sepsis and LPS-induced endotoxemia. </LI> </UL> </P>

The mechanism and signal for the nuclear import of O-GlcNAc transferase

Hyeon Gyu Seo,Han Byeol Kim,Min Jueng Kang,Joo Hwan Rym,Eugene C. Yi,Jin Won Cho 한국당과학회 2016 한국당과학회 학술대회 Vol.2016 No.01

Uridine diphosphate-N-acetyl glucosamine, generated from glucose via the hexosamine biosynthetic pathway, is a substrate for O -linked-N-acetylglucosamine (O -GlcNAc). Addition and removal of O -linked-N-acetylglucosamine to Ser/Thr residues is a dynamic cycle and is involved in the regulation of nuclear and cytoplasmic proteins. Nucleocytoplasmic O -GlcNActransferase (OGT) attaches a single GlcNAc onto hydroxyl groups of serine and threonine residues. Although the cellular localization of OGT is important to regulate a variety of cellular processes, the molecular mechanism regulating the nuclear localization of OGT is unclear. Here, we characterized the NLS motif in OGT and this motif is required for the nuclear import of non-diffusible β -galactosidase. OGT bound the importin α5 protein, and this association was abolished when the NLS motif of ncOGT was mutated or deleted. We also revealed that O -GlcNAcylation on tetratricopeptide repeats (TPR) plays an important role in nuclear localization of OGT. Our finding suggests the mechanism behind how OGT can be localized in the nucleus and cytosol simultaneously.

Identification and characterization of nuclear localization signal in O-GlcNAc transferase and its nuclear import regulation

Hyeon Gyu Seo,Han Byeol Kim,Min Jueng Kang,Joo Hwan Rym,Eugene C. Yi,Jin Won Cho 한국당과학회 2016 한국당과학회 학술대회 Vol.2016 No.07

Nucleocytoplasmic O-GlcNAc transferase (OGT) attaches a single GlcNAc to hydroxyl groups of serine and threonine residues. Although the cellular localisation of OGT is important to regulate a variety of cellular processes, the molecular mechanisms regulating the nuclear localisation of OGT is unclear. Here, we characterised three amino acids (DFP; residues 451–453) as the nuclear localisation signal of OGT and demonstrated that this motif mediated the nuclear import of non-diffusible β-galactosidase. OGT bound the importin α5 protein, and this association was abolished when the DFP motif of OGT was mutated or deleted. We also revealed that O-GlcNAcylation of Ser389, which resides in the tetratricopeptide repeats, plays an important role in the nuclear localisation of OGT. Our findings may explain how OGT, which possesses a NLS, exists in the nucleus and cytosol simultaneously.

Heme-binding-mediated negative regulation of the tryptophan metabolic enzyme indoleamine 2,3-dioxygenase 1 (IDO1) by IDO2

Lee, Young-Kwan,Lee, Hoon Bok,Shin, Dong-Mi,Kang, Min Jueng,Yi, Eugene C,Noh, Seungjoo,Lee, Jaewoo,Lee, Chulbom,Min, Chang-Ki,Choi, Eun Young Nature Publishing Group 2014 Experimental and molecular medicine Vol.46 No.11

<P>Indoleamine 2,3-dioxygenases (IDOs) are tryptophan-catabolizing enzymes with immunomodulatory functions. However, the biological role of IDO2 and its relationship with IDO1 are unknown. To assess the relationship between IDO2 and IDO1, we investigated the effects of co-expression of human (h) IDO2 on hIDO1 activity. Cells co-expressing hIDO1 and hIDO2 showed reduced tryptophan metabolic activity compared with those expressing hIDO1 only. In a proteomic analysis, hIDO1-expressing cells exhibited enhanced expression of proteins related to the cell cycle and amino acid metabolism, and decreased expression of proteins related to cell survival. However, cells co-expressing hIDO1 and hIDO2 showed enhanced expression of negative regulators of cell apoptosis compared with those expressing hIDO1 only. Co-expression of hIDO1 and hIDO2 rescued the cell death induced by tryptophan-depletion through hIDO1 activity. Cells expressing only hIDO2 exhibited no marked differences in proteome profiles or cell growth compared with mock-transfectants. Cellular tryptophan metabolic activity and cell death were restored by co-expressing the hIDO2 mutant substituting the histidine 360 residue for alanine. These results demonstrate that hIDO2 plays a novel role as a negative regulator of hIDO1 by competing for heme-binding with hIDO1, and provide information useful for development of therapeutic strategies to control cancer and immunological disorders that target IDO molecules.</P>

UBR box N-recognin-4 (UBR4), an N-recognin of the N-end rule pathway, and its role in yolk sac vascular development and autophagy

Tasaki, Takafumi,Kim, Sung Tae,Zakrzewska, Adriana,Lee, Bo Eun,Kang, Min Jueng,Yoo, Young Dong,Cha-Molstad, Hyun Joo,Hwang, Joonsung,Soung, Nak Kyun,Sung, Ki Sa,Kim, Su-Hyeon,Nguyen, Minh Dang,Sun, Mi National Academy of Sciences 2013 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.110 No.10

<P>The N-end rule pathway is a proteolytic system in which destabilizing N-terminal residues of short-lived proteins act as degradation determinants (N-degrons). Substrates carrying N-degrons are recognized by N-recognins that mediate ubiquitylation-dependent selective proteolysis through the proteasome. Our previous studies identified the mammalian N-recognin family consisting of UBR1/E3α, UBR2, UBR4/p600, and UBR5, which recognize destabilizing N-terminal residues through the UBR box. In the current study, we addressed the physiological function of a poorly characterized N-recognin, 570-kDa UBR4, in mammalian development. UBR4-deficient mice die during embryogenesis and exhibit pleiotropic abnormalities, including impaired vascular development in the yolk sac (YS). Vascular development in UBR4-deficient YS normally advances through vasculogenesis but is arrested during angiogenic remodeling of primary capillary plexus associated with accumulation of autophagic vacuoles. In the YS, UBR4 marks endoderm-derived, autophagy-enriched cells that coordinate differentiation of mesoderm-derived vascular cells and supply autophagy-generated amino acids during early embryogenesis. UBR4 of the YS endoderm is associated with a tissue-specific autophagic pathway that mediates bulk lysosomal proteolysis of endocytosed maternal proteins into amino acids. In cultured cells, UBR4 subpopulation is degraded by autophagy through its starvation-induced association with cellular cargoes destined to autophagic double membrane structures. UBR4 loss results in multiple misregulations in autophagic induction and flux, including synthesis and lipidation/activation of the ubiquitin-like protein LC3 and formation of autophagic double membrane structures. Our results suggest that UBR4 plays an important role in mammalian development, such as angiogenesis in the YS, in part through regulation of bulk degradation by lysosomal hydrolases.</P>