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1.  Role of VPO1, a newly identified heme-containing peroxidase, in ox-LDL induced endothelial cell apoptosis 
Free radical biology & medicine  2011;51(8):1492-1500.
Myeloperoxidase (MPO) is an important enzyme involved in the genesis and development of atherosclerosis. Vascular peroxidase 1 (VPO1) is a newly discovered member of the peroxidase family that is mainly expressed in vascular endothelial cells and smooth muscle cells and has structural characteristics and biological activity similar to those of MPO. Our specific aims were to explore the effects of VPO1 on endothelial cell apoptosis induced by oxidized low-density lipoprotein (ox-LDL) and the underlying mechanisms. The results showed that ox-LDL induced endothelial cell apoptosis and the expression of VPO1 in endothelial cells in a concentration- and time-dependent manner concomitant with increased intracellular reactive oxygen species (ROS) and hypochlorous acid (HOCl) generation, and up-regulated protein expression of the NADPH oxidase gp91phox subunit and phosphorylation of p38 MAPK. All these effects of ox-LDL were inhibited by VPO1 gene silencing and NADPH oxidase gp91phox subunit gene silencing or by pretreatment with the NADPH oxidase inhibitor apocynin or diphenyliodonium. The p38 MAPK inhibitor SB203580 or the caspase-3 inhibitor DEVD-CHO significantly inhibited ox-LDL-induced endothelial cell apoptosis, but had no effect on intracellular ROS and HOCl generation or the expression of NADPH oxidase gp91phox subunit or VPO1. Collectively, these findings suggest for the first time that VPO1 plays a critical role in ox-LDL-induced endothelial cell apoptosis and that there is a positive feedback loop between VPO1/HOCl and the now-accepted dogma that the NADPH oxidase/ROS/p38 MAPK/caspase-3 pathway is involved in ox-LDL-induced endothelial cell apoptosis.
doi:10.1016/j.freeradbiomed.2011.07.004
PMCID: PMC3570029  PMID: 21820048
VPO1; MPO; NADPH oxidase; Apoptosis; Endothelial cells; Free radicals
2.  The molecular basis of making spiral ganglion neurons and connecting them to hair cells of the organ of Corti 
Hearing research  2011;278(1-2):21-33.
The bipolar spiral ganglion neurons predominantly delaminate from the growing cochlear duct and migrate to Rosenthal’s canal. They project radial fibers to innervate the organ of Corti (type I neurons to inner hair cells, type II neurons to outer hair cells) and also project tonotopically to the cochlear nuclei. The early differentiation of these neurons requires transcription factors to regulate migration, pathfinding and survival. Neurog1 null mice lack formation of neurons. Neurod1 null mice show massive cell death combined with aberrant central and peripheral projections. Prox1 protein is necessary for proper type II neuron process navigation, which is also affected by the neurotrophins Bdnf and Ntf3. Neurotrophin null mutants show specific patterns of neuronal loss along the cochlea but remaining neurons compensate by expanding their target area. All neurotrophin mutants have reduced radial fiber growth proportional to the degree of loss of neurotrophin alleles. This suggests a simple dose response effect of neurotrophin concentration. Keeping overall concentration constant, but misexpressing one neurotrophin under regulatory control of another one results in exuberant fiber growth not only of vestibular fibers to the cochlea but also of spiral ganglion neurons to outer hair cells suggesting different effectiveness of neurotrophins for spiral ganglion neurite growth. Finally, we report here for the first time that losing all neurons in double null mutants affects extension of the cochlear duct and leads to formation of extra rows of outer hair cells in the apex, possibly by disrupting the interaction of the spiral ganglion with the elongating cochlea.
doi:10.1016/j.heares.2011.03.002
PMCID: PMC3130837  PMID: 21414397
ear; spiral ganglion; development; neuronal survival
3.  Krüppel-Like Factor 8 Is a New Wnt/Beta-Catenin Signaling Target Gene and Regulator in Hepatocellular Carcinoma 
PLoS ONE  2012;7(6):e39668.
Krüppel-like factor 8 (KLF8) plays important role in cell cycle and oncogenic transformation. Here we report the mechanisms by which KLF8 crosstalks with Wnt/β-catenin signaling pathway and regulates hepatocellular carcinoma (HCC) cells proliferation. We show that overexpression of KLF8 and nucleus accumulation of β-catenin in the human HCC samples are positively correlated. More importantly, KLF8 protein levels plus nucleus accumulation of β-catenin levels were significantly elevated in high-grade HCC compared to low-grade HCC. Using HCC HepG2 cells we find that, on the one hand both protein and mRNA of KLF8 are up-regulated under Wnt3a stimulation, on the other hand overexpression of KLF8 increases the cytoplasm and nucleus accumulation of β-catenin, recruits p300 to β-catenin/T-cell factor 4 (TCF4) transcription complex, enhances TOP flash report gene transcription, and induces Wnt/β-catenin signaling target genes c-Myc, cyclin D1 and Axin1 expression. Knockdown of KLF8 using shRNA inhibits Wnt3a induced transcription of TOP flash report gene and expression of c-Myc, cyclin D1 and Axin1. Knockdown of β-catenin by shRNA rescues the enhanced HepG2 and Hep3B cells proliferation ability induced by overexpression of KLF8.
doi:10.1371/journal.pone.0039668
PMCID: PMC3384617  PMID: 22761862
4.  Concomitant lung metastasis in patients with advanced hepatocellular carcinoma 
AIM: To investigate the clinical features and prognostic factors of advanced hepatocellular carcinoma (HCC) patients presenting with lung metastasis at initial diagnosis.
METHODS: Between 2001 and 2010, we recruited 76 consecutive HCC patients initially presenting with lung metastasis, without co-existing metastasis from other sites. These patients were divided into three groups: untreated group (n = 22), single treatment group (n = 19), and combined treatment group (n = 35).
RESULTS: Metastasis of bilateral lung lobes was common and noted in 35 patients (46.1%), and most of patients (59/76, 77.6%) presented with multiple lung metastatic nodules. Nineteen patients (25.0%) received single-method treatment, including hepatectomy in 4, transcatheter arterial chemoembolization in 6, radiotherapy in 5, and oral sorafenib in 4. Thirty-five patients (46.1%) received combined treatment modalities. The overall median survival of the all patients was 8.7 ± 0.6 mo; 4.1 ± 0.3, 6.3 ± 2.5 and 18.6 ± 3.9 mo, respectively in the untreated group, single treatment group and combined treatment group, respectively, with a significant difference (log-rank test, P < 0.001). Multivariate analysis revealed that Child-Pugh score, the absence or presence of portal vein tumor thrombus, and treatment modality were three independent prognostic factors affecting survival of patients with advanced HCC and concomitant lung metastasis.
CONCLUSION: Combined treatment modalities tend to result in a better survival as compared with the conservative treatment or single treatment modality for HCC patients initially presenting with lung metastasis.
doi:10.3748/wjg.v18.i20.2533
PMCID: PMC3360452  PMID: 22654451
Hepatocellular carcinoma; Lung metastasis; Prognosis; Survival; Prognostic factor
5.  Descriptive data on cancerous lung lesions detected by auto-fluorescence bronchoscope: A five-year study 
Annals of Thoracic Medicine  2012;7(1):21-25.
BACKGROUND:
Auto-fluorescence bronchoscopy (AFB) has been used for the identification and localization of intra-epithelial pre-neoplastic and neoplastic lesions within the bronchus.
OBJECTIVES:
To determine the applicability of AFB for the detection and localization of precancerous and cancerous lesions, in addition to analyzing the morphologic presentation, their association to histological type and the variation between genders.
METHODS:
A five-year study involving 4983 patients, who underwent routine bronchoscopy [B] examination in a local tertiary teaching hospital, was done. The B examination was performed under intratracheal lidocaine, and samples were obtained using suitable approach. One thousand four hundred and eighty-five pathologically confirmed lung cancer patients were included in the study. The following parameters were studied: Morphological presentation, biopsy sites, histology. Differences between the groups were analyzed using Chi square test.
RESULT:
One thousand four hundred and eighty-five patients who had hyperplasia or neoplastic lesions were further confirmed as lung cancer pathologically. Lung cancer was more commonly found in the right lung (51.58% vs. 42.82%). The lesion occurred more frequently in the upper lobe than the lower lobe (44.17% vs. 22.42%). Male patients with squamous cell carcinoma showed upper lobe involvement more commonly, while the left main bronchus was more commonly involved in female patients. Adenocarcinoma mostly involved lesion of the upper lobe. Squamous cell carcinoma and small cell carcinoma were the major proliferative types (80.15% and 76.16% respectively).
CONCLUSION:
AFB is efficient in the detection of pre-invasive and invasive lung lesions. The morphological presentation is associated to the histological type. There is variation in the presentation and histology of cancerous lung lesions between genders.
doi:10.4103/1817-1737.91559
PMCID: PMC3277036  PMID: 22347346
Auto-fluorescence bronchoscopy; gender; invasive lesion; lung cancer; screening
6.  Isoflurane Preconditioning at Clinically Relevant Doses Induce Protective Effects of Heme Oxygenase-1 on Hepatic Ischemia Reperfusion in Rats 
BMC Gastroenterology  2011;11:31.
Background
Activation of heme oxygenase-1 (HO-1) has been proved to reduce damages to the liver in ischemia reperfusion injury. The objective of present study was to determine whether clinic relevant doses of isoflurane treatment could be sufficient to activate HO-1 inducing, which confers protective effect against hepatic ischemia-reperfusion injury.
Methods
The hepatic artery and portal vein to the left and the median liver lobes of forty male Sprague-Dawley rats were occluded for 60 minutes. Reperfusion was allowed for 4 hours before the animal subjects were sacrificed. Six groups (n = 12) were included in the study. A negative control group received sham operation and positive control group a standard ischemia-reperfusion regimen. The third group was pretreated with isoflurane prior to the ischemia-reperfusion. The fourth group received an HO-1 inhibitor zinc protoporphyrin (Znpp) prior to the isoflurane pretreatment and the ischemia-reperfusion. The fifth group received Znpp alone before ischemia-reperfusion procedure, and the sixth group was administrated with a HO-1 inducer hemin prior to IR. HO-1 in the liver was measured using an enzymatic activity assay, a Western blot analysis, as well as immunohistochemical method. Extent of liver damage was estimated by determination of the serum transaminases, liver lipid peroxidation and hepatic histology. Infiltration of the liver by neutrophils was measured using a myeloperoxidase activity assay. TNFα mRNA in the liver was measured using RT-PCR.
Results
Isoflurane pretreatment significantly attenuated the hepatic injuries and inflammatory responses caused by the ischemia reperfusion. Selectively inhibiting HO-1 with ZnPP completed blocked the protective effects of isoflurane. Inducing HO-1 with hemin alone produced protective effects similar in magnitude to that of isoflurane.
Conclusions
Clinic relevant doses of isoflurane attenuate ischemia reperfusion injury in rats by increasing the HO-1 expression and activity.
doi:10.1186/1471-230X-11-31
PMCID: PMC3088533  PMID: 21453462
7.  Results of the proximal femoral nail anti-rotation (PFNA) in elderly Chinese patients 
International Orthopaedics  2009;33(5):1441-1444.
A prospective study is presented of 87 unstable intertrochanteric fractures treated with the proximal femoral nail anti-rotation (PFNA) with a follow-up of one year. Of the patients 76% were female. The average age was 75.3 years. The fracture was treated by closed reduction and intramedullary fixation. Pre-injury activity level was recovered in 77% of the patients. Fractures united in all patients. Mechanical failure and cut-out were not observed. A technical problem related to the mismatch of the proximal end of the nail was observed in 11 cases. Nine patients presented with thigh pain due to the redundant proximal end of the nail. The results of the PFNA were satisfactory in most elderly Chinese patients. However, the proximal end of the nail was not matched with the specific anatomy of some short elderly patients. Further modifications of the nail are necessary for the elderly Chinese population.
doi:10.1007/s00264-009-0776-3
PMCID: PMC2899136  PMID: 19367404
8.  Differential Expression and Glycosylation of Anaplasma phagocytophilum Major Surface Protein 2 Paralogs during Cultivation in Sialyl Lewis x-Deficient Host Cells▿  
Infection and Immunity  2009;77(5):1746-1756.
Many microbial pathogens alter expression and/or posttranslational modifications of their surface proteins in response to dynamics within their host microenvironments to retain optimal interactions with their host cells and/or to evade the humoral immune response. Anaplasma phagocytophilum is an intragranulocytic bacterium that utilizes sialyl Lewis x (sLex)-modified P-selectin glycoprotein ligand 1 as a receptor for infecting myeloid cells. Bacterial populations that do not rely on this receptor can be obtained through cultivation in sLex-defective cell lines. A. phagocytophilum major surface protein 2 [Msp2(P44)] is encoded by members of a paralogous gene family and is speculated to play roles in host adaptation. We assessed the complement of Msp2(P44) paralogs expressed by A. phagocytophilum during infection of sLex-competent HL-60 cells and two HL-60 cell lines defective for sLex expression. Multiple Msp2(P44) and N-terminally truncated 25- to 27-kDa isoforms having various isoelectric points and electrophoretic mobilities were expressed in each cell line. The complement of expressed msp2(p44) paralogs and the glycosyl residues modifying Msp2(P44) varied considerably among bacterial populations recovered from sLex-competent and -deficient host cells. Thus, loss of host cell sLex expression coincided with both differential expression and glycosylation of A. phagocytophilum Msp2(P44). This reinforces the hypothesis that this bacterium is able to generate a large variety of surface-exposed molecules that could provide great antigenic diversity and result in multiple binding properties.
doi:10.1128/IAI.01530-08
PMCID: PMC2681760  PMID: 19223475
9.  Characterization of Rat Hair Follicle Stem Cells Selected by Vario Magnetic Activated Cell Sorting System 
Acta Histochemica et Cytochemica  2009;42(5):129-136.
Hair follicle stem cells (HfSCs) play crucial roles in hair follicle morphogenesis and hair cycling. These stem cells are self-renewable and have the multi-lineage potential to generate epidermis, sebaceous glands, and hair follicle. The separation and identification of hair follicle stem cells are important for further research in stem cell biology. In this study, we report on the successful enrichment of rat hair follicle stem cells through vario magnetic activated cell sorting (Vario MACS) and the biological characteristics of the stem cells. We chose the HfSCs positive surface markers CD34, α6-integrin and the negative marker CD71 to design four isolation strategies: positive selection with single marker of CD34, positive selection with single marker of α6-integrin, CD71 depletion followed by CD34 positive selection, and CD71 depletion followed by α6-integrin positive selection. The results of flow cytometry analysis showed that all four strategies had ideal effects. Specifically, we conducted a series of researches on HfSCs characterized by their high level of CD34, termed CD34bri cells, and low to undetectable expression of CD34, termed CD34dim cells. CD34bri cells had greater proliferative potential and higher colony-forming ability than CD34dim cells. Furthermore, CD34bri cells had some typical characteristics as progenitor cells, such as large nucleus, obvious nucleolus, large nuclear:cytoplasmic ratio and few cytoplasmic organelles. Our findings clearly demonstrated that HfSCs with high purity and viability could be successfully enriched with Vario MACS.
doi:10.1267/ahc.09016
PMCID: PMC2775103  PMID: 19918321
hair follicle stem cell; stem cell purification; enrichment; surface markers
10.  IgE myeloma with elevated level of serum CA125 
Objective: To explore clinical and laboratory features and significance of detecting serum carbohydrate antigen 125 (CA125) in immunoglobulin E (IgE) multiple myeloma. Methods: We reported the clinical findings of a male patient with IgE myeloma and elevated level of serum CA125 and reviewed the literature. Results: Laboratory tests of this patient on admission showed extremely high serum IgE and CA125, a bone marrow aspirate revealed abnormal plasma cells (38.4% of nucleated cells: 16.4% mature and 22% atypical), and in bone marrow biopsy, immunoperoxidase staining showed positive cytoplasmic staining for IgE and κ light chain within the vast majority of plasma cells. Computed tomography (CT) bone scans indicated wedge shape change and compressive fracture of thoracic vertebrae, and emission computed tomography (ECT) discovered multiple punctiform aggregation of radiation in both cervical ribs and spine. The serum IgE and CA125 gradually decreased to normal limits after eight cycles of chemotherapy. This patient is alive well with an 18-month complete remission. Conclusion: We reported the first case of IgE myeloma with elevated level of serum CA125. To further evaluate clinical characteristics and significance of CA125 in IgE myeloma, more cases are needed.
doi:10.1631/jzus.B0820399
PMCID: PMC2704975  PMID: 19585675
Immunoglobulin E (IgE); Multiple myeloma; Carbohydrate antigen 125 (CA125)
11.  Expression Pattern of Cyclooxygenase-2 in Normal Rat Epidermis and Pilosebaceous Unit during Hair Cycle 
Acta Histochemica et Cytochemica  2008;41(6):157-163.
As an important member of the cyclooxygenase isoenzymes, cyclooxygenase-2 (COX-2) mainly catalyzes the first two steps in prostanoid synthesis. In mammalian animals, although COX-2 was thought to be rarely expressed in most normal tissues and was usually upregulated in a variety of epithelial tumors and inflammatory reactions, recently it was reported that COX-2 could localize in the epidermis as well as the pilosebaceous unit of the normal human and mouse skin. Until now, the function of COX-2 in normal skin has remained unknown. To investigate the possible roles of COX-2 in normal skin by RT-PCR and immunochemistry, we studied the expression pattern of COX-2 in hair cycle of the normal rat skin. The expression of COX-2 mRNA was detected in normal rat skin sample and was related to the hair follicle cycle. When the hair cycle entered catagen and telogen, COX-2 mRNA transcription in skin increased significantly. Furthermore, the location of COX-2 immunoreactivity showed that COX-2 protein is mainly concentrated in the epidermis and pilosebaceous unit. In the stratified epidermis, the strong COX-2 protein expression was detected in the suprabasal layers of epidermis in anagen and declined in catagen and telogen. In hair follicle, COX-2 protein was obviously expressed in the outer root sheath of the anagen hair follicle, and was barely detectable in catagen as well as telogen. In the sebaceous gland, the COX-2 protein expression became more intense in catagen and telogen, with an increase in sebaceous gland size. Our results suggested that COX-2 was not specific to some abnormal tissues and was indeed involved in the normal physiology of rat skin, such as the differentiation of epidermis, the morphogenesis of the hair follicle, the transformation of hair cycle stages, and the lipid production of the sebaceous gland.
doi:10.1267/ahc.08024
PMCID: PMC2629551  PMID: 19180200
cyclooxygenase-2; pilosebaceous unit; hair cycle; epidermis; sebaceous glands
12.  Anaplasma phagocytophilum MSP2(P44)-18 Predominates and Is Modified into Multiple Isoforms in Human Myeloid Cells▿  
Infection and Immunity  2008;76(5):2090-2098.
Anaplasma phagocytophilum is the etiologic agent of human granulocytic anaplasmosis. MSP2(P44), the bacterium's major surface protein, is encoded by a paralogous gene family and has been implicated in a variety of pathobiological processes, including antigenic variation, host adaptation, adhesion, porin activity, and structural integrity. The consensus among several studies performed at the DNA and RNA levels is that a heterogeneous mix of a limited number of msp2(p44) transcripts is expressed by A. phagocytophilum during in vitro cultivation. Such analyses have yet to be extended to the protein level. In this study, we used proteomic and molecular approaches to determine that MSP2(P44)-18 is the predominant if not the only paralog expressed and is modified into multiple 42- to 44-kDa isoforms by A. phagocytophilum strain HGE1 during infection of HL-60 cells. The msp2(p44) expression profile was homogeneous for msp2(p44)-18. Thus, MSP2(P44)-18 may have a fitness advantage in HL-60 cell culture in the absence of selective immune pressure. Several novel 22- to 27-kDa MSP2 isoforms lacking most of the N-terminal conserved region were also identified. A. phagocytophilum MSP2(P44) orthologs expressed by other pathogens in the family Anaplasmataceae are glycosylated. Gas chromatography revealed that recombinant MSP2(P44)-18 is modified by glucose, galactose, xylose, mannose, and trace amounts of other glycosyl residues. These data are the first to confirm differential modification of any A. phagocytophilum MSP2(P44) paralog and the first to provide evidence for expression of truncated versions of such proteins.
doi:10.1128/IAI.01594-07
PMCID: PMC2346672  PMID: 18285495
13.  Role of Biotransformation Studies in Minimizing Metabolism-Related Liabilities in Drug Discovery 
The AAPS Journal  2008;10(1):178-192.
Metabolism-related liabilities continue to be a major cause of attrition for drug candidates in clinical development. Such problems may arise from the bioactivation of the parent compound to a reactive metabolite capable of modifying biological materials covalently or engaging in redox-cycling reactions leading to the formation of other toxicants. Alternatively, they may result from the formation of a major metabolite with systemic exposure and adverse pharmacological activity. To avert such problems, biotransformation studies are becoming increasingly important in guiding the refinement of a lead series during drug discovery and in characterizing lead candidates prior to clinical evaluation. This article provides an overview of the methods that are used to uncover metabolism-related liabilities in a pre-clinical setting and offers suggestions for reducing such liabilities via the modification of structural features that are used commonly in drug-like molecules.
doi:10.1208/s12248-008-9016-9
PMCID: PMC2751461  PMID: 18446518
bioactivation; biotransformation; CYP; drug discovery; glutathione; metabolism

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