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1.
Biochem Biophys Res Commun ; 601: 9-15, 2022 04 23.
Article in English | MEDLINE | ID: mdl-35219001

ABSTRACT

Keratinocytes produce lipids that are critical for the skin barrier, however, little is known about the impact of age on fatty acid (FA) biosynthesis in these cells. We have examined the relationship between keratinocyte FA composition, lipid biosynthetic gene expression, gene promoter methylation and age. Expression of elongase (ELOVL6 and 7) and desaturase (FADS1 and 2) genes was lower in adult versus neonatal keratinocytes, and was associated with lower concentrations of n-7, n-9 and n-10 polyunsaturated FA in adult cells. Consistent with these findings, transient FADS2 knockdown in neonatal keratinocytes mimicked the adult keratinocyte FA profile in neonatal cells. Interrogation of methylation levels across the FADS2 locus (53 genomic sites) revealed differential methylation of 15 sites in neonatal versus adult keratinocytes, of which three hypermethylated sites in adult keratinocytes overlapped with a SMARCA4 protein binding site in the FADS2 promoter.


Subject(s)
DNA Methylation , Delta-5 Fatty Acid Desaturase , Fatty Acid Desaturases , Fatty Acids, Unsaturated , Keratinocytes , Adult , DNA Helicases/metabolism , Fatty Acid Desaturases/genetics , Fatty Acid Desaturases/metabolism , Fatty Acids, Unsaturated/metabolism , Humans , Infant, Newborn , Keratinocytes/metabolism , Nuclear Proteins/metabolism , Promoter Regions, Genetic , Transcription Factors/metabolism
2.
Int J Tuberc Lung Dis ; 23(11): 1171-1177, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31718753

ABSTRACT

OBJECTIVE: To examine the associations between endotoxin and (1,3)-ß-glucan concentrations in office dust and respiratory symptoms and airway inflammation among 695 office workers in Malaysia.METHODS: Health data were collected using a questionnaire, sensitisation testing and measurement of fractional exhaled nitric oxide (FeNO). Indoor temperature, relative air humidity (RH) and carbon dioxide (CO2) were measured in the offices and settled dust was vacuumed and analysed for endotoxin and (1,3)-ß-glucan concentrations. Associations were analysed by two level multiple logistic regression.RESULTS: Overall, 9.6% of the workers had doctor-diagnosed asthma, 15.5% had wheeze, 18.4% had daytime attacks of breathlessness and 25.8% had elevated FeNO (≥25 ppb). The median levels in office dust were 11.3 EU/mg endotoxin and 62.9 ng/g (1,3)-ß-glucan. After adjusting for personal and home environment factors, endotoxin concentration in dust was associated with wheeze (P = 0.02) and rhinoconjunctivitis (P = 0.007). The amount of surface dust (P = 0.04) and (1,3)-ß-glucan concentration dust (P = 0.03) were associated with elevated FeNO.CONCLUSION: Endotoxin in office dust could be a risk factor for wheeze and rhinoconjunctivitis among office workers in mechanically ventilated offices in a tropical country. The amount of dust and (1,3)-ß-glucan (a marker of indoor mould exposure) were associated with Th2 driven airway inflammation.


Subject(s)
Asthma/epidemiology , Dust/analysis , Dyspnea/epidemiology , Endotoxins/analysis , Rhinitis/epidemiology , beta-Glucans/analysis , Adult , Air Pollution, Indoor/analysis , Carbon Dioxide/analysis , Female , Humans , Humidity , Logistic Models , Malaysia/epidemiology , Male , Nitric Oxide/analysis , Respiratory Sounds/etiology , Temperature , Tropical Climate , Workplace
4.
Osteoarthritis Cartilage ; 24(10): 1826-1836, 2016 10.
Article in English | MEDLINE | ID: mdl-27211863

ABSTRACT

OBJECTIVE: Recent evidence suggests a role of fibrogenesis in intervertebral disc (IVD) degeneration. We aim to explore if fibrotic genes may serve as IVD degeneration indicators, and if their expression is associated with myofibroblast activity. DESIGN: Transcriptional expression of fibrosis markers (COL1A1, COL3A1, FN1, HSP47, MMP12, RASAL1) were analyzed in degenerated (D) and non-degenerated (ND) human nucleus pulposus (NP) and annulus fibrosus (AF) cells, along with traditional (SOX9, ACAN) and newly established degeneration markers (CDH2, KRT19, KRT18, FBLN1, MGP, and COMP). Protein expression was investigated by immunohistochemistry in human IVDs, and in rodent IVDs undergoing natural ageing or puncture-induced degeneration. Co-expression with myofibroblast markers was examined by double staining on human and rat specimens. Disc degeneration severity and extent of fibrosis were determined by histological scoring and picrosirius red staining respectively. RESULTS: Human D-NP showed more intensive staining for picrosirius red than ND-NP. Among the genes examined, D-NP showed significantly higher MMP12 expression along with lower KRT19 expression. Protein expression analysis revealed increased MMP12(+) cells in human D-IVD. Histological scoring indicated mild degeneration in the punctured rat discs and discs of ageing mouse. Higher MMP12 positivity was found in peripheral NP and AF of the degenerative rat discs and in NP of the aged mice. In addition, human D-NP and D-AF showed increased α-SMA(+) cells, indicating enhanced myofibroblast activity. MMP12 was found co-expressed with α-SMA, FSP1 and FAP-α in human and rat degenerative IVDs. CONCLUSIONS: Our study suggests that in addition to a reduced KRT19 expression, an increased expression of MMP12, a profibrotic mediator, is characteristic of disc degenerative changes. Co-expression study indicates an association of the increased MMP12 positivity with myofibroblast activity in degenerated IVDs. Overall, our findings implicate an impact of MMP12 in disc cell homeostasis. The precise role of MMP12 in IVD degeneration warrants further investigation.


Subject(s)
Intervertebral Disc Degeneration , Animals , Biomarkers , Fibrosis , Humans , Intervertebral Disc , Matrix Metalloproteinase 12 , Mice , Nucleus Pulposus , Rats
5.
Clin Oncol (R Coll Radiol) ; 26(11): 684-91, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25194727

ABSTRACT

AIMS: At our centre, ductal carcinoma in situ (DCIS) was commonly treated with breast-conservation therapy (BCT). Local recurrence after BCT is a major concern. The aims of our study were to review the outcomes of DCIS treatment in our patients and to evaluate a nomogram from Memorial Sloan Kettering Cancer Centre (MSKCC) for predicting ipsilateral breast tumour recurrence (IBTR) in our Asian population. MATERIALS AND METHODS: Chart reviews of 716 patients with pure DCIS treated from 1992 to 2011 were carried out. Univariable Cox regression analyses were used to evaluate the effects of the 10 prognostic factors of the MSKCC nomogram on IBTR. We constructed a separate National Cancer Centre Singapore (NCCS) nomogram based on multivariable Cox regression via reduced model selection by applying the stopping rule of Akaike's information criterion to predict IBTR-free survival. The abilities of the NCCS nomogram and the MSKCC nomogram to predict IBTR of individual patients were evaluated with bootstrapping of 200 sets of resamples and the NCCS dataset, respectively. Harrell's c-index was calculated for each nomogram to evaluate the concordance between predicted and observed responses of individual subjects. RESULTS: Study patients were followed up for a median of 70 months. Over 95% of patients received adjuvant radiotherapy. The 5 and 10 year actuarial IBTR-free survival rates for the cohort were 95.5 and 92.6%, respectively. In the multivariate analysis, independent prognostic factors for IBTR included use of adjuvant endocrine therapy, presence of comedonecrosis and younger age at diagnosis. These factors formed the basis of the NCCS nomogram, which had a similar c-index (NCCS: 0.696; MSKCC: 0.673) compared with the MSKCC nomogram. CONCLUSION: The MSKCC nomogram was validated in an Asian population. A simpler NCCS nomogram using a different combination of fewer prognostic factors may be sufficient for the prediction of IBTR in Asians, but requires external validation to compare for relative performance.


Subject(s)
Breast Neoplasms/surgery , Carcinoma, Intraductal, Noninfiltrating/surgery , Mastectomy, Segmental , Neoplasm Recurrence, Local/diagnosis , Nomograms , Asia/epidemiology , Breast Neoplasms/pathology , Carcinoma, Intraductal, Noninfiltrating/pathology , Female , Follow-Up Studies , Humans , Incidence , Middle Aged , Neoplasm Staging , Predictive Value of Tests , Retrospective Studies
6.
Int J Cosmet Sci ; 36(5): 419-26, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24811958

ABSTRACT

OBJECTIVE: Dandruff is a troubling consumer problem characterized by flaking and pruritus of the scalp and is considered a multifactorial condition with sebum, individual susceptibility and the fungus Malassezia all thought to play a part. The condition is commonly treated with shampoo products containing antifungal ingredients such as zinc pyrithione and climbazole. It is hypothesized that these ingredients may be delivering additional scalp skin benefits besides their antifungal activity helping to relieve dandruff effectively. The objective of this study was to evaluate the anti-dandruff ingredient climbazole for potential skin benefits using genomics and in vitro assays. METHODS: Microarray analysis was performed to profile gene expression changes in climbazole-treated primary human keratinocyte cells. Results were independently validated using qPCR and analysis of protein expression using ELISA and immunocytochemistry. RESULTS: Microarray analysis of climbazole-treated keratinocytes showed statistically significant expression changes in genes associated with the gene ontology groups encompassing epidermal differentiation, keratinization, cholesterol biosynthesis and immune response. Upregulated genes included a number encoding cornified envelope proteins such as group 3 late-cornified envelope proteins, LCE3 and group 2 small-proline-rich proteins, SPRR2. Protein analysis studies of climbazole-treated primary keratinocytes using ELISA and immunocytochemistry were able to demonstrate that the increase in gene transcripts translated into increased protein expression of these cornified envelope markers. CONCLUSION: Climbazole treatment of primary keratinocytes results in an upregulation in expression of a number of genes including those encoding proteins involved in cornified envelope formation with further studies demonstrating this did translate into increased protein expression. A climbazole-driven increase in cornified envelope proteins may improve the scalp skin barrier, which is known to be weaker in dandruff. These studies suggest climbazole, besides its antifungal activity, is delivering positive skin benefits helping to relive dandruff symptoms effectively.


Subject(s)
Imidazoles/pharmacology , Keratinocytes/drug effects , Proteins/metabolism , Cells, Cultured , Enzyme-Linked Immunosorbent Assay , Humans , Keratinocytes/metabolism , Oligonucleotide Array Sequence Analysis , Proteins/genetics , Real-Time Polymerase Chain Reaction
7.
Transplant Proc ; 38(9): 2761-5, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17112824

ABSTRACT

Current attitudes toward organ donation among university students in mainland China and the differences in attitudes between Chinese students in mainland China versus overseas are unknown. To address these issues, we conducted a cross-sectional survey using questionnaires among 922 Chinese undergraduates from mainland China and overseas regions of the world. Data were analyzed by descriptive statistics, Student t tests, chi-square tests, and a logistic regression analysis. We found that blood donors showed significantly better awareness of heart, liver, lung, skin, and tendon donation among commonly transplanted organs/tissues. As to the willingness for cadaveric organ donation, 61.3% of respondents consented, 8.5% objected, and 30.3% answered "not sure." The percentage holding an organ donor card was 15.7% among students from Hong Kong; 3.0%, mainland China; 2.8%, Macau; 2.6%, Taiwan, and 4.0%, other regions of the world. In a logistic regression analysis, female students (odds ratio [OR], 2.24; 95% confidence interval [CI], 1.35 to 3.72) and blood donors (OR, 1.91; 95% CI, 1.10 to 3.32) did, but age and study specialty (medical vs nonmedical) did not show significantly more positive attitudes toward cadaveric organ donation. Compared with students from mainland China, overseas Chinese students from various regions did not show significantly different attitudes toward cadaveric organ donation. In summary, blood donors among university students have a greater knowledge of transplantation and a more positive attitude toward organ donation. Since university students are an important source of blood donors in China, they will be a potential pool of organ donors in the future.


Subject(s)
Health Knowledge, Attitudes, Practice , Students , Tissue and Organ Procurement , Adult , China , Demography , Female , Humans , Male , Regression Analysis , Tissue and Organ Procurement/statistics & numerical data , Universities
8.
Xenobiotica ; 36(10-11): 1140-51, 2006.
Article in English | MEDLINE | ID: mdl-17118921

ABSTRACT

The circadian clock controls many aspects of mammalian physiology and behaviour with a periodicity of approximately 24 h. These include the anticipation of, and adaptation to, daily environmental changes such as the light-dark cycle, temperature fluctuations and the availability of food. The toxicity of many drugs is dependent on the circadian phase at which they are administered, and recent work has begun to unravel the molecular basis for circadian variations in sensitivity to xenobiotic exposure. Between 2 and 10% of the transcriptome is expressed in a circadian manner, including many key genes associated with the metabolism and transport of xenobiotics. Furthermore, a number of xenobiotics may directly alter the expression of genes that control circadian rhythms. This review discusses the emerging evidence for the regulation of circadian rhythm genes having an important impact on molecular response to xenobiotics.


Subject(s)
Circadian Rhythm/drug effects , Xenobiotics/pharmacology , Animals , Circadian Rhythm/genetics , Gene Expression Regulation/drug effects , Humans , Inactivation, Metabolic/genetics , Neoplasms/pathology
9.
J Mol Endocrinol ; 34(2): 535-51, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15821115

ABSTRACT

Estrogen receptor (ER)-negative breast carcinomas do not respond to hormone therapy, making their effective treatment very difficult. The re-expression of ERalpha in ER-negative MDA-MB-231 breast cancer cells has been used as a model system, in which hormone-dependent responses can be restored. Paradoxically, in contrast to the mitogenic activity of 17beta-estradiol (E2) in ER-positive breast cancer cells, E2 suppresses proliferation in ER-negative breast cancer cells in which ERalpha has been re-expressed. We have used global gene expression profiling to investigate the mechanism by which E2 suppresses proliferation in MDA-MB-231 cells that express ERalpha through adenoviral infection. We show that a number of genes known to promote cell proliferation and survival are repressed by E2 in these cells. These include genes encoding the anti-apoptosis factor SURVIVIN, positive cell cycle regulators (CDC2, CYCLIN B1, CYCLIN B2, CYCLIN G1, CHK1, BUB3, STK6, SKB1, CSE1 L) and chromosome replication proteins (MCM2, MCM3, FEN1, RRM2, TOP2A, RFC1). In parallel, E2-induced the expression of the negative cell cycle regulators KIP2 and QUIESCIN Q6, and the tumour-suppressor genes E-CADHERIN and NBL1. Strikingly, the expression of several of these genes is regulated in the opposite direction by E2 compared with their regulation in ER-positive MCF-7 cells. Together, these data suggest a mechanism for the E2-dependent suppression of proliferation in ER-negative breast cancer cells into which ERalpha has been reintroduced.


Subject(s)
Breast Neoplasms , Cell Proliferation/drug effects , Estrogen Receptor alpha/metabolism , Estrogens/pharmacology , Gene Expression Regulation, Neoplastic , Genes, cdc , Adenoviridae/genetics , Adenoviridae/metabolism , Antigens, Neoplasm/genetics , Antigens, Neoplasm/metabolism , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line, Tumor , Estrogen Receptor alpha/genetics , Female , Gene Expression Profiling , Genes, Reporter , Humans , Inhibitor of Apoptosis Proteins , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Molecular Sequence Data , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Oligonucleotide Array Sequence Analysis , Survivin
11.
EMBO J ; 19(14): 3750-61, 2000 Jul 17.
Article in English | MEDLINE | ID: mdl-10899128

ABSTRACT

In the yeast Saccharomyces cerevisiae, the MADS-box protein Mcm1, which is highly related to mammalian SRF (serum response factor), forms a ternary complex with SFF (Swi five factor) to regulate the cell cycle expression of genes such as SWI5, CLB2 and ACE2. Here we show that the forkhead protein Fkh2 is a component of SFF and is essential for ternary complex formation on the SWI5 and ACE2 promoters. Fkh2 is essential for the correct cell cycle periodicity of SWI5 and CLB2 gene expression and is phosphorylated with a timing that is consistent with a role in this expression. Furthermore, investigation of the relationship between Fkh2 and a related forkhead protein Fkh1 demonstrates that these proteins act in overlapping pathways to regulate cell morphology and cell separation. This is the first example of a eukaryotic transcription factor complex containing both a MADS-box and a forkhead protein, and it has important implications for the regulation of mammalian gene expression.


Subject(s)
Cell Cycle Proteins , Cell Cycle/genetics , Gene Expression Regulation, Fungal , Nuclear Proteins/metabolism , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae/genetics , Transcription Factors/chemistry , Transcription Factors/metabolism , Cell Nucleus/metabolism , Consensus Sequence/genetics , Cyclin B/genetics , Cyclin B/metabolism , Cyclins/genetics , DNA, Fungal/genetics , DNA, Fungal/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Forkhead Transcription Factors , Fungal Proteins/genetics , Fungal Proteins/metabolism , G2 Phase/genetics , Gene Deletion , Genes, Fungal/genetics , Minichromosome Maintenance 1 Protein , Nuclear Proteins/genetics , Phosphorylation , Promoter Regions, Genetic/genetics , Protein Binding , RNA, Messenger/metabolism , Response Elements/genetics , Saccharomyces cerevisiae/cytology , Saccharomyces cerevisiae/metabolism , Spindle Apparatus/metabolism , Transcription Factors/genetics
12.
EMBO J ; 19(11): 2615-28, 2000 Jun 01.
Article in English | MEDLINE | ID: mdl-10835359

ABSTRACT

The solution structure of the 33 kDa complex between the dimeric DNA-binding core domain of the transcription factor MEF2A (residues 1-85) and a 20mer DNA oligonucleotide comprising the consensus sequence CTA(A/T)(4)TAG has been solved by NMR. The protein comprises two domains: a MADS-box (residues 1-58) and a MEF2S domain (residues 59-73). Recognition and specificity are achieved by interactions between the MADS-box and both the major and minor grooves of the DNA. A number of critical differences in protein-DNA contacts observed in the MEF2A-DNA complex and the DNA complexes of the related MADS-box transcription factors SRF and MCM1 provide a molecular explanation for modulation of sequence specificity and extent of DNA bending ( approximately 15 versus approximately 70 degrees ). The structure of the MEF2S domain is entirely different from that of the equivalent SAM domain in SRF and MCM1, accounting for the absence of cross-reactivity with other proteins that interact with these transcription factors.


Subject(s)
DNA-Binding Proteins/chemistry , DNA/chemistry , Transcription Factors/chemistry , Amino Acid Sequence , Cross Reactions , DNA/metabolism , DNA-Binding Proteins/metabolism , Dimerization , Humans , MADS Domain Proteins , MEF2 Transcription Factors , Macromolecular Substances , Magnetic Resonance Spectroscopy , Minichromosome Maintenance 1 Protein , Models, Molecular , Molecular Sequence Data , Myogenic Regulatory Factors , Nuclear Proteins/chemistry , Nuclear Proteins/metabolism , Nucleic Acid Conformation/drug effects , Protein Binding , Protein Conformation , Protein Structure, Tertiary , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism , Regulatory Sequences, Nucleic Acid , Sequence Alignment , Sequence Homology, Amino Acid , Serum Response Factor , Solutions , Structure-Activity Relationship , Transcription Factors/classification , Transcription Factors/metabolism , Transcription Factors/pharmacology
13.
Oncogene ; 17(15): 2013-8, 1998 Oct 15.
Article in English | MEDLINE | ID: mdl-9788446

ABSTRACT

SSX genes show extensive nucleotide sequence conservation but little is known of their function. Disruption of SSX1 or SSX2, by chromosome translocation and 'in-frame' fusion to SYT, is a consistent feature of synovial sarcomas. The resulting SYT-SSX1/SSX2 proteins are activators of transcription; transactivation function is located in SYT. Unrearranged SSX1 can repress transcription, and this has been attributed to a putative Krüppel associated box (KRAB) repression domain at the N-terminus. Here we isolated SSX-KRAB domains to specifically measure repression activity, using a previously characterized KOX1-KRAB domain as a control. In our repressor assay SSX1- and SSX2-KRAB domains down-modulated the transactivation of a reporter gene by threefold, compared with 83-fold repression achieved by KOX1-KRAB in the assay. Yeast two-hybrid analysis showed that SSX1-KRAB, unlike KOX1-KRAB, fails to interact with the KRAB co-repressor TIF1beta. These results raise questions about the evolutionary and functional relationship of SSX-KRAB and typical KRAB domains of Krüppel zinc finger genes. We found that full-length SSX1 showed potent (74-fold) repression in our repressor assay, indicating the existence of a repression domain distinct from SSX-KRAB. By assaying deletion constructs of SSX1 we localized repression activity to 33 amino acids at the C-terminus. This novel domain is conserved between SSX family members, and, unlike the KRAB-related domain, is retained on fusion with SYT. This has important implications in understanding the mechanism by which the SYT-SSX fusion protein could contribute to neoplasia.


Subject(s)
DNA-Binding Proteins , Neoplasm Proteins/genetics , Repressor Proteins/genetics , Sarcoma/genetics , Transcription, Genetic , Amino Acid Sequence , Humans , Kruppel-Like Transcription Factors , Molecular Sequence Data , Sequence Homology, Amino Acid
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