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Recent publications
 

Dr. Nan-Shan Chang

 

Dr. Li-Wha Wu

 

Dr. Chi-Wu Chiang

 

Dr. Ching-Hao Teng

 

Dr. Hsiao-Fang Sun

 

Dr. Shainn-Wei Wang

  Dr. Christina Ling Chang  

 

 
  Nan-Shan Chang, Ph.D.
 

1)Chang JY, Chiang MF, Lin SR, Lee MH, He H, Chou PY, Chen SJ, Chen YA, Yang LY, Lai FJ, Hsieh TH, Sheu HM, Sze CI, Chang NS (2012) TIAF1 self-aggregation in peritumor capsule formation, spontaneous activation of SMAD-responsive promoter in p53-deficient environment, and cell death. Cell Death &Disease, 3, e302;

2) Chiang MF, Chou PY, Wang WJ, Sze CI and Chang NS (2013) Tumor suppressor WWOX and p53 alterations and drug resistance in glioblastomas. Front. Oncol.3:43.

3) Sze C, Su W, Chiang M, Chen Y and Chang NS (2013). Assessing current therapeutic approaches to decode potential resistance mechanisms in glioblastomas. Front. Oncol. 3:59.

4) Hong Q, Hsu LJ, Chou PY, Chou YT, Lu CY, Chen YA, Nan-Shan Chang NS (2013) Self-aggregating TIAF1 in lung cancer progression. Translational Respiratory Medicine1:5.
TIAF1 protein is frequently expressed in the proliferating GBM cells, probably due to the stimulation of micro-environmental factors in the brain. The intracellular TIAF1 undergoes self-aggregation, may induce caspase activation, and leads to phosphorylation and degradation of membrane amyloid precursor protein (APP), generation of amyloid beta (Ab) and formation of amyloid fibrils. Secreted Ab42 is toxic to neurons. Also, Ab42 undergoes self-polymerization and binds secreted TIAF1, and the complexes are probably detrimental to neurons. Ab is indeed localized intracellularly. Cancer cells are resistant to the toxic effect of polymerized TIAF1 and Ab. The presence of intracellular aggregated TIAF1 and amyloid fibrils in the tumor is likely to prevent amyloid precursor protein the penetration and efficacy of therapeutic drugs.
 

  in HP, Chang JY, Lin SR, Lee MH, Huang SS, Hsu LJ, Chang NS. Identification of an In Vivo MEK/WOX1 Complex as a Master Switch for Apoptosis in T Cell Leukemia. Genes Cancer. 2011 May;2(5):550-62.
Cancer cells are believed to be diehard or they never die. Assuming that there is a switch for turning on/off death in cancer cells, we discovered that when tumor suppressor WWOX or WOX1 is in association with a kinase MEK1, leukemia T cells do not undergo apoptosis. However, when the WOX1/MEK1 complex becomes dissociated, leukemia cells die. This phenomenon can also be observed in other types of cancer cells. We are the first group to isolate the WWOX gene in year 2000. Mechanistically, upon dissociation, WOX1 relocates to the mitochondria and nuclei to initiate the apoptotic event. We used PMA (phorbol myristate acetate) as a trigger to induce the WOX1/MEK1 dissociation and subsequent apoptosis. We are seeking additional triggers, which are safer for clinical therapeutics. Clearly, the WOX1/MEK1 complex is a molecular switch for turning on/off cancer cell death.
 
  Lee MH, Lin SR, Chang JY, Schultz L, Heath J, Hsu LJ, Kuo YM, Hong Q, Chiang MF, Gong CX, Sze CI, Chang N-S (2010) TGF-b induces TIAF1 self-aggregation via type II receptor-independent signaling that leads to generation of amyloid plaques in Alzheimer’s disease. Cell Death & Disease, 1, e110. (Editor’s choice of Article of the Month)
The role of a small transforming growth factor beta (TGF-β)-induced TIAF1 (TGF-β1-induced antiapoptotic factor) in the pathogenesis of Alzheimer's disease (AD) was investigated. TIAF1 physically interacts with mothers against DPP homolog 4 (Smad4), and blocks SMAD-dependent promoter activation when overexpressed. Accordingly, knockdown of TIAF1 by small interfering RNA resulted in spontaneous accumulation of Smad proteins in the nucleus and activation of the promoter governed by the SMAD complex. TGF-β1 and environmental stress (e.g., alterations in pericellular environment) may induce TIAF1 self-aggregation in a type II TGF-β receptor-independent manner in cells, and Smad4 interrupts the aggregation. Aggregated TIAF1 induces apoptosis in a caspase-dependent manner. By filter retardation assay, TIAF1 aggregates were found in the hippocampi of nondemented humans and AD patients. Total TIAF1-positive samples containing amyloid β (Aβ) aggregates are 17 and 48%, respectively, in the nondemented and AD groups, suggesting that TIAF1 aggregation occurs preceding formation of Aβ. To test this hypothesis, in vitro analysis showed that TGF-β-regulated TIAF1 aggregation leads to dephosphorylation of amyloid precursor protein (APP) at Thr668, followed by degradation and generation of APP intracellular domain (AICD), Aβ and amyloid fibrils. Polymerized TIAF1 physically interacts with amyloid fibrils, which would favorably support plaque formation in vivo.
 

Breakthrough Discovery: Cell surface Hyal-2 is a cognate receptor for TGF-b1

Type II TGF-b receptor (TbRII) is a key component in the TGF-b signaling, which involves the binding of TGF-b to TbRII, followed by recruiting type I receptor (TbRI) and assembling the Smad2/3/4 signaling complex for relocating to the nuclei.  Here, Dr. Nan-Shan Chang and colleagues discovered that cell surface hyaluronidase Hyal-2 is a cognate receptor for TGF-b1 as shown in TbRII-negative colon HCT116 cells (left panel: immunoelectron microscopy; large beads for Hyal-2 and small beads for TGF-b1 on microvilli).  The TGF-b1/Hyal-2 complex recruits tumor suppressor WWOX to the membrane, and the resulting Hyal-2/WWOX complex translocates to the nuclei for enhancing the SMAD promoter activation (right panel).

References: J Biol Chem 284, 16049, 2009; Exp Biol Med 235, 796, 2010, review. 

 
 
  Li-Wha Wu, Ph.D.
 

Pan SC, Wu LW (co-corresponder), Chen CL, Shieh SJ, Chiu HY. 2010 May. Deep partial thickness burn blister fluid promotes neovascularization in the early stage of burn wound healing. Wound Repair Regeneration 18:311-8 (2010, May).

The effect of burn blister fluid in neovascularization during burn wound healing is unknown. Burn blister fluid, containing a large amount of chemokines, is thought to play a role in the early stage of neovascularization. This process includes angiogenesis and vasculogenesis. Because of different healing time of burn wounds, we hypothesized that neovascularization in superficial partial thickness burn (SPTB) and deep partial thickness burn (DPTB) wounds were different. The neovasculogenic effects of two different burn blister fluids were also different. We found Day 7 DPTB wounds had a significant increase in blood vessels compared with SPTB wounds by immunohistochemistry. DPTB blister fluid significantly promoted neovascularization via increasing endothelial cell proliferation, and migration and differentiation of circulating angiogenic cells relative to SPTB blister fluids. In the animal study, DPTB blister fluids markedly promoted new blood vessel formation compared with those from SPTB blister fluids using in vivo Matrigel plug assay. These results suggest that DPTB wounds require more new vessel formation than SPTB. Furthermore, the measurement of angiogenic activities in burn blister fluids serves as a possible tool for assessing burn wound status.

 

 

Tsai ST, Chien IH, Shen WH, Kuo YZ, Jin YT, Wong TY, Hsiao JR, Wang HP, Shih NY, Wu LW. 2010 Jun. ENO1, a potential prognostic head and neck cancer marker, promotes transformation partly via chemokine CCL20 induction.
European Journal of Cancer 46:1712-23.

The success of using glycolytic inhibitors for cancer treatment depends on studying the individual role of frequently deregulated glycolytic genes in cancer. This report aims to study the prognostic implication, and determine the cellular role and action mechanism of glycolytic ENO1 overexpression in head and neck cancer. The relationship of ENO1 mRNA expression in 44-pair clinical specimens with patient clinicopathologic characteristics was analysed by semi-quantitative RT-PCR, Kaplan-Meier survival curve and Cox model analyses. Following ectopic ENO1 expression or knockdown, we studied the proliferative, migratory, invasive, colony-forming and tumourigenic abilities of ENO1-genetically altered cells. DNA microarray analysis was used to identify downstream targets responsible for the ENO1 action in the cells. The expression of ENO1 mRNA was increased in 68% of tumour (T) specimens when compared to their normal (N) counterparts, and positively associated with clinical progression (p<0.05). High ENO1 expression (T/N2) was frequently observed in the patients with large primary tumours, late clinical stages or advanced neck metastasis. Moreover, high ENO1 patients had significantly poorer clinical outcomes than low expressers (T/N<2). Ectopic ENO1 expression stimulated cell transformation, invasion and tongue tumour formation. ENO1 knockdown abrogated the stimulation. Suppression of ENO1-induced proinflammatory CCL20 chemokine expression significantly attenuated its stimulatory effects on cell transformation and invasion. A concordant expression of ENO1 and CCL20 was validated both in ENO1-expressing cells and in clinical specimens. Together, we demonstrate a prognostic role of ENO1 overexpression in head and neck cancer and ENO1-mediated promotion of cell transformation and invasion partly via induced CCL20 expression.

 

Kao YC, Wu LW, Shi CS, Chu CH, Huang CW, Kuo CP, Sheu HM, Shi GY, Wu HL. 2010 Oct. Down-regulation of thrombomodulin, a novel target of Snail, induces tumorigenesis through epithelial-mesenchymal transition.
Molecular and Cellular Biology30:4767-85 .

The expression of thrombomodulin (TM), a calcium-dependent adhesion molecule, is frequently downregulated in various cancer types. However, the mechanism responsible for the low expression level of TM in tumorigenesis is unknown. Here, an inverse expression of TM and Snail was detected in different cancer cell lines. We further confirmed this inverse relation using the epithelial-mesenchymal transition cell model in HaCaT and A431 cells. We demonstrated that Snail suppressed TM expression by binding to E-box (CACCTG) in TM promoter. Moreover, TM knockdown by short hairpin RNA disrupted E-cadherin-mediated cell junctions and contributed to tumorigenesis. In the calcium switch assay, E-cadherin lost the ability to associate with β-catenin and accumulated in cytoplasm in TM knockdown cells. Meanwhile, wound healing and invasive assays showed that TM knockdown promoted cell motility. A subcutaneous injection of TM knockdown transfectants into immunocompromised mice induced squamous cell carcinoma-like tumors. Besides, forced expression of murine TM in TM knockdown cells made the cells reassume epithelium-like morphology and increased calcium-dependent association of E-cadherin and β-catenin. In conclusion, TM, a novel downstream target of Snail in epithelial-mesenchymal transition, is required for maintaining epithelial morphology and functions as a tumor suppressor
 
 
  Christina Ling Chang, Ph.D.
 

Li I-C, Chiu C-Y, Wu C-L, Chi J-Y, Jian S-R, Wang S-W, and Chang CL. A dual-fluorescent reporter facilitates identification of thiol compounds that suppress microsatellite instability induced by oxidative stress. Free Radical Biology and Medicine. 2014 April; 69:86–95.

Patients with chronic inflammation or inflammation-associated cancer display microsatellite instability (MSI), indicating a possible inactivation of DNA mismatch repair (MMR). We previously reported that H2O2-generated oxidative stress inactivates the MMR function and increases mutation accumulation in a reporter microsatellite. Here, we developed a more sensitive, convenient and reliable dual-fluorescent MSI reporter system. Via this reporter, glutathione or N-acetylcysteine was found to be better than aspirin and ascorbic acid for suppressing oxidative microsatellite mutations. MSI suppression by N-acetylcysteine appears to be mediated through reduction of oxidative frameshift mutations in the coding microsatellite of hMSH6 gene, and protection of hMSH6 and other MMR protein levels from being decreased by H2O2. Our findings suggest a linkage between oxidative damage, MMR deficiency and MSI. The two thiol compounds are potentially valuable for preventing inflammation-associated MSI. The dual-fluorescent reporter will facilitate identification of additional compounds that modulate MSI, which is relevant to cancer initiation and progression.

 

 

 
 
  Chi-Wu Chiang, Ph.D.
 

Yen C. J., Lin Y. J., Yen C. S., Tsai H. W., Tsai T. F., Chang K. Y., Huang W. C., Lin P. W., Chiang C. W. (co-corresponding), Chang T. T. Hepatitis B Virus X Protein Upregulates mTOR Signaling through IKKβ to Increase Cell Proliferation and VEGF Production in Hepatocellular Carcinoma. (2012) PLoS One. 2012;7(7):e41931.

Hepatocellular carcinoma (HCC), a major cause of cancer-related death in Southeast Asia, is frequently associated with hepatitis B virus (HBV) infection. HBV X protein (HBx), encoded by a viral non-structural gene, is a multifunctional regulator in HBV-associated tumor development. We investigated novel signaling pathways underlying HBx-induced liver tumorigenesis and found that the signaling pathway involving IκB kinase β (IKKβ), tuberous sclerosis complex 1 (TSC1), and mammalian target of rapamycin (mTOR) downstream effector S6 kinase (S6K1), was upregulated when HBx was overexpressed in hepatoma cells. HBx-induced S6K1 activation was reversed by IKKβ inhibitor Bay 11-7082 or silencing IKKβ expression using siRNA. HBx upregulated cell proliferation and vascular endothelial growth factor (VEGF) production, and these HBx-upregulated phenotypes were abolished by treatment with IKKβ inhibitor Bay 11-7082 or mTOR inhibitor rapamycin. The association of HBx-modulated IKKβ/mTOR/S6K1 signaling with liver tumorigenesis was verified in a HBx transgenic mouse model in which pIKKβ, pS6K1, and VEGF expression was found to be higher in cancerous than non-cancerous liver tissues. Furthermore, we also found that pIKKβ levels were strongly correlated with pTSC1 and pS6K1 levels in HBV-associated hepatoma tissue specimens taken from 95 patients, and that higher pIKKβ, pTSC1, and pS6K1 levels were correlated with a poor prognosis in these patients. Taken together, our findings demonstrate that HBx deregulates TSC1/mTOR signaling through IKKβ, which is crucially linked to HBV-associated HCC development.

 

 

 

Hsu C. C., Chiang C. W., Cheng H. C., Chang W. T., Chou C. Y., Tsai H. W., Lee C. T., Wu Z. H., Lee T. Y., Chao A, Chow N. H., Ho C. L. Identifying LRRC16B as an oncofetal gene with transforming enhancing capability using a combined bioinformatics and experimental approach. Oncogene (2011). 30:654-667.(Chung-Liang Ho,Ph.D.、Chi-Wu Chiang,Ph.D.)

Oncofetal genes are expressed in embryos or fetuses, are downregulated or undetectable in adult tissues, and then re-expressed in tumors. Known oncofetal genes, such as AFP, GCB, FGF18, IMP-1 and SOX1, often have important clinical applications or pivotal biological functions. To find new oncofetal-like genes, we used the public information of expressed sequence tags to systematically analyze gene expression patterns and identified a novel oncofetal-like gene, LRRC16B. It increased the proliferation, anchorage-independent growth and tumorigenesis of transformed cells in xenografts, possibly through its effects on cyclin B1 protein levels. These findings exemplify the feasibility of using bioinformatics to find new oncofetal-like genes and suggest that more genes with important functional roles will be uncovered in the candidate gene list.

 

 

Lee TY, Lai TY, Lin SC, Wu CW, Ni IF, Yang YS, Hung LY, Law BK, and Chiang CW: The B56γ3 Regulatory Subunit of Protein Phosphatase 2A (PP2A) Regulates S Phase-specific Nuclear Accumulation of PP2A and the G1 to S Transition. 2010 July; J. Biol. Chem. 285 (28): 21567-21580

Protein phosphatase 2A (PP2A) is a heterotrimeric enzyme consisting of a scaffold subunit (A), a catalytic subunit (C), and a variable regulatory subunit (B). The regulatory B subunits determine the substrate specificity and subcellular localization of the PP2A holoenzyme. Here, we demonstrate that the subcellular localization of the B56γ3 regulatory subunit is regulated in a cell cycle-specific manner. Notably, B56γ3 becomes enriched in the nucleus at the G1/S border and in S phase. The S phase-specific nuclear enrichment of B56γ3 is accompanied by increases of nuclear A and C subunits and nuclear PP2A activity. Overexpression of B56γ3 promotes nuclear localization of the A and C subunits, whereas silencing both B56g2 and B56g3 blocks the S phase-specific increase in the nuclear localization and activity of PP2A. In NIH3T3 cells, B56g3 overexpression reduces p27 phosphorylation at Thr187, concomitantly elevates p27 protein levels, delays the G1 to S transition, and retards cell proliferation. Consistently, knockdown of endogenous B56g3 expression reduces p27 protein levels and increases cell proliferation in HeLa cells. These findings demonstrate that the dynamic nuclear distribution of the B56γ3 regulatory subunit controls nuclear PP2A activity, which regulates cell cycle controllers, such as p27, to restrain cell cycle progression, and may be responsible for the tumor suppressor function of PP2A.

 

 

Chiang CW, Liu WK, Chiang CW (co-corresponding), and Chou CK: Phosphorylation-dependent association of the G4-1/G5PR regulatory subunit with IKKβ negatively modulates NF-κB activation through recruitment of protein phosphatase 5, Biochem. J. 2011 433, 187-196

The transcription factor NF-κB (nuclear factor-kappa B) coordinates various gene expressions in response to diverse signals and is a critical regulator of inflammation and innate immunity. Several negative regulators of NF-κB have been identified as downstream targets of NF-κB and function as a feedback control of NF-κB activation. A few protein phosphatases have also been shown to inactivate NF-κB activation. However, little is known about how protein phosphatases detect and respond to NF-κB activation. In the present study, we report a regulatory subunit of PP5 (protein phosphatase 5), G4-1, that physically interacts with IKKβ [IκB (inhibitor of NF-κB) kinase β] and negatively regulates NF-κB activation. The association of G4-1 with IKKβ depends on the kinase activity of IKKβ. Mapping of the G4-1-binding domain of IKKβ reveals that the serine-rich domain in the C-terminus of IKKβ is required for G4-1 binding. When seven autophosphorylated serine residues in this domain were mutated to alanine, the mutant form of IKKβ lost its ability to bind G4-1 and was more potent than the wild-type kinase to activate NF-κB. Knockdown of G4-1 enhanced TNFα (tumour necrosis factor α)-induced NF-κB activity, and knockdown of PP5 totally abolished the inhibitory activity of G4-1 on NF-κB activation. The results of the present study suggest that G4-1 functions as an adaptor to recruit PP5 to the phosphorylated C-terminus of activated IKKβ and to down-regulate the activation of IKKβ.
 

 
 
  Ching-Hao Teng, Ph.D.
 

Teng, Ching-Hao, Y. T. Tseng, R. Maruvada, D. Pearce, Y. Xie, M. Paul-Satyaseela, and K. S. Kim. 2010/7. NlpI contributes to Escherichia coli K1 strain RS218 interaction with human brain microvascular endothelial cells. Infection and Immunity 78:3090-3096.

E. coli K1 is the most common gram-negative bacillary organism causing neonatal meningitis. E. coli K1 binding to and invasion of human brain microvascular endothelial cells (HBMECs) is a prerequisite for its traversal of the blood-brain barrier (BBB) and penetration into the brain. In the current study we identified NlpI as a novel bacterial determinant contributing to E. coli K1 interaction with HBMECs. The deletion of nlpI did not affect the expression of the known bacterial determinants involved in E. coli K1-HBMEC interaction, such as type 1 fimbriae, flagella and OmpA, and the contribution of NlpI to HBMECs binding and invasion was independent of those bacterial determinants. Previous reports have shown that the nlpI mutant of E. coli K-12 exhibits growth defect at 42ºC at low osmolarity and its thermosensitive phenotype can be suppressed by a mutation on the spr gene. The nlpI mutant of strain RS218 exhibited similar thermosensitive phenotype, but additional spr mutation did not restore the ability of the nlpI mutant to interact with HBMECs. These findings suggest the decreased ability of the nlpI mutant to interact with HBMECs is not associated with the thermosensitive phenotype. NlpI was determined as an outer membrane-anchored protein in E. coli and the nlpI mutant was defective in cytosolic phospholiase A2α (cPLA2α) phosphorylation compared to the parent strain. These findings illustrate the first demonstration of NlpI’s contribution to E. coli K1 binding to and invasion of HBMECs, and its contribution is likely to involve cPLA2α.

 
 
  Hsiao-Fang Sun,Ph.D.
 

Tsung-Ming Chen, Yu-Heng Shih, Joseph T. Tseng, Chih-Hao Wu, Yi-Han Lee, Shaw-Jenq Tsai*, and H. Sunny Sun*.Overexpression of FGF9 in colon cancer cells is mediated by hypoxia-induced translational activation..Nucleic acids research. 42(5):2932-44.

Human fibroblast growth factor 9 (FGF9) is a potent mitogen involved in many physiological processes. Although FGF9 mRNA is ubiquitously expressed in embryos, FGF9 protein expression is generally low and restricted to a few adult organs. Aberrant expression of FGF9 usually results in human malignancies including cancers, but the mechanism remains largely unknown. Here, we report that FGF9 protein, but not mRNA, was increased in hypoxia. Two sequence elements, the upstream open reading frame (uORF) and the internal ribosome entry site (IRES) were identified in the 5'UTR of FGF9 mRNA. Functional assays indicated that FGF9 protein synthesis was normally controlled by uORF-mediated translational repression, which kept the protein at a very low level, but was upregulated in response to hypoxia through a switch to IRES-dependent translational control. Our data demonstrate that FGF9 IRES functions as a cellular switch to turn FGF9 protein synthesis “on” during hypoxia, a likely mechanism underlying FGF9 overexpression in cancer cells. Finally, we provide evidence to show that hypoxia-induced translational activation promotes FGF9 protein expression in colon cancer cells. All together, this dynamic working model may provide a new direction in anti-tumor therapies and cancer intervention.

  Chao SC, Chen JS, Tsai CH, Lin JM, Lin YJ, Sun HS.Novel exon nucleotide substitution at the splice junction causes a neonatal Marfan syndrome.Clin Genet. 2010 May;77(5):453-63.
The fibrillin-1 gene (FBN1) mutations are associated with a broad spectrum of disorders including Marfan syndrome (MFS) and show great clinical heterogeneity. An underrepresentation for mutations leading to premature termination codon (PTC) in FBN1 exons 24-32 was found in neonatal or severe MFS but the underlying cause was unclear. This study thoroughly examined two FBN1 mutations on exons 24-32 region to illustrate the molecular mechanisms underlying these FBN1 mutations on MFS etiology. Two nucleotide substitutions, c.3208G> C, the last nucleotide of exon 26, and c.3209A>G, the first nucleotide of exon 27, affecting the same amino acid, p.D1070H and p.D1070G, respectively, gave very different phenotypes. We demonstrate that c.3208G>C generates two alternatively spliced transcripts, while c.3209A>G does not affect the splicing. We further demonstrate that the aberrantly spliced transcripts do not go through nonsense-mediated decay, but rather produce unstable, premature protein peptides that are degraded by endoplasmic reticulum associated degradation. The molecular mechanism outlined here defines a model for the pathogenesis of PTC-containing mutation within the exons 24-32 of FBN1 in MFS. Furthermore, our data suggest that PTC mutation within this region may lead to early lethality in neonatal MFS.
 
 

Chen TM, Hsu CH, Tsai SJ, Sun HS.AUF1 p42 isoform selectively controls both steady-state and PGE2-induced FGF9 mRNA decay.Nucleic Acids Res. 2010 Dec 1;38(22):8061-71.

Fibroblast growth factor 9 (FGF9) is an autocrine/paracrine growth factor that plays vital roles in many physiologic processes including embryonic development. Aberrant expression of FGF9 causes human diseases and thus it highlights the importance of controlling FGF9 expression; however, the mechanism responsible for regulation of FGF9 expression is largely unknown. Here, we show the crucial role of an AU-rich element (ARE) in FGF9 3'-untranslated region (UTR) on controlling FGF9 expression. Our data demonstrated that AUF1 binds to this ARE to regulate FGF9 mRNA stability. Overexpression of each isoform of AUF1 (p37, p40, p42 and p45) showed that only the p42 isoform reduced the steady-state FGF9 mRNA. Also, knockdown of p42(AUF1) prolonged the half-life of FGF9 mRNA. The induction of FGF9 mRNA in prostaglandin (PG) E(2)-treated human endometrial stromal cells was accompanied with declined cytoplasmic AUF1. Nevertheless, ablation of AUF1 led to sustained elevation of FGF9 expression in these cells. Our study demonstrated that p42(AUF1) regulates both steady-state and PGE(2)-induced FGF9 mRNA stability through ARE-mediated mRNA degradation. Since almost half of the FGF family members are ARE-containing genes, our findings also suggest that ARE-mediated mRNA decay is a common pathway to control FGFs expression, and it represents a novel RNA regulon to coordinate FGFs homeostasis in various physiological conditions.
 

 
 
  Shainn-Wei Wang,Ph.D.
 

Jun-Wei Lee, Pao-Chi Liao, Kung-Chia Young, Christina L. Chang, Steve S.L. Chen, Ting-Tsung Chang, Ming-Derg Lai, Shainn-Wei Wang* (*Corresponder) Identification of hnRNPH1, NF45, and C14orf166 as novel host interacting partners of the mature hepatitis C virus core protein.J Proteome Res. 2011 Aug 8. [Epub ahead of print]


The hepatitis C virus core protein (HCVc) forms the viral nucleocapsid and is involved in viral persistence and pathogenesis, possibly by interacting with host factors to modulate viral replication and cellular functions. Here, we identified 36 cellular protein candidates by one-dimensional SDS-PAGE and LC-MS/MS-based proteomics after affinity purification with HCVc174, a matured form of HCVc from HCV-1b genotype, tagged with biotin and calmodulin-binding peptide/protein A at N- and C-termini, respectively. By pull-down and confocal imaging techniques, we confirmed that heterogeneous nuclear ribonucleoprotein H1 (hnRNPH1), nuclear factor 45 (NF45), and C14orf166 are novel HCVc174-interacting host proteins, known to participate in mRNA metabolism, gene regulation, and microtubule organization, respectively. Unlike the other 2 proteins, NF45 interacted with HCVc174 in an RNA-dependent manner. These 3 proteins co-localized with ectopic HCVc-1b in both the cytoplasm and nucleus, which demonstrated their spatial interaction with naturally translocated HCVc174 after HCVc biogenesis. Such co-localization, however, shifted to the cytoplasm in cells with replicating virus of 1b or 2a genotype, indicating that active viral replication confined these interacting proteins in the cytoplasm. Collectively, our findings suggest that spatial interactions of hnRNPH1, NF45, and C14orf166 with HCVc174 likely modulate HCV or cellular functions during acute and chronic HCV infection.

 

Wang JH, Cheng L, Wang CH, Ling W, Wang SW*, and Lee GB*. An integrated chip capable of performing sample pretreatment and nucleic acid amplification for HIV-1 detection. Biosensors and Bioelectronics. Accepted. 2012 Sep 27. BIOS-D-12-01947R1, pii: S0956-5663(12)00617-3. doi: 10.1016/j.bios.2012.09.011. [Epub ahead of print]PMID:23083906, Impact factor 5.602, Ranking 1/27. Co-corresponder.


This study reports on a microfluidic system equipped with a sample pretreatment device and a nucleic acid amplification device for the rapid diagnosis of the human immunodeficiency virus‐1 (HIV‐1). The system analyzed proviral deoxyribonucleic acid (DNA) from an HIV‐infected Jurkat T cell line. In order to ensure accurate diagnosis among other prevalent B‐type strains, simultaneous detections of four conserved HIV‐1 B‐type DNA fragments were performed in this integrated microfluidic system. The entire protocol including cell lysis, extraction of DNA, polymerase chain reaction (PCR), and optical detection were successfully integrated in order to perform a rapid, automated diagnosis. Experimental results showed that four primer sets with conserved HIV‐1 B‐type sequences specific for the 167‐bp RU5 promoter region, the 424‐bp int, the 117‐bp tat, and the 162‐bp vpr coding regions were successfully amplified from the respective regions of the proviral DNA, even from a single infected cell. This accurate real‐time detection was achieved within 95 min using the integrated optical system.

 
 
 

 

 

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