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1.
Ann Oncol ; 27(6): 1129-1134, 2016 06.
Article in English | MEDLINE | ID: mdl-27013394

ABSTRACT

BACKGROUND: Breast cancer incidence rates are increasing among Asian women, likely due to the changes in risk factors caused by globalization. Trends in breast cancer rates among Chinese women may differ from other Asian regions due to the implementation of a nationwide family planning program and resulting changes in women's reproductive practices. Appraisal of cancer trends can direct cancer control and public health planning, but relevant studies in China are scarce due to a lack of long-term data. We sought to evaluate secular time trends in breast cancer incidence and mortality using 40 years of cancer registry data for women in urban Shanghai. MATERIALS AND METHODS: Data on invasive breast cancer incidence and mortality were collected by the Shanghai Cancer Registry. Age-standardized rates (ASRs) for incidence and mortality were calculated using the Segi/Doll 1960 world standard population. Age, period, and birth cohort effects were evaluated using age-period-cohort (APC) Poisson regression models. Overall linear trends, interpreted as the estimated annual percentage change (EAPC), were derived from the net drift in age-drift models. RESULTS: A total of 53 885 breast cancer cases and 17 235 breast cancer-specific deaths were documented among women in urban Shanghai between 1 January 1973 and 31 December 2012. Breast cancer incidence and mortality ASRs increased by 141.2% and 26.6%, respectively. Significant age, cohort, and period effects were identified in both incidence and mortality APC models; cohort effects were pronounced. Overall, a substantial increase in breast cancer incidence (EAPC = 2.96%/year) and a moderate increase in breast cancer mortality (EAPC = 0.87%/year) was observed. A notable downward trend in mortality was identified among younger women born after 1960. CONCLUSIONS: Forty years of cancer registry data document a tremendous increase in incidence and a slight increase in mortality for breast cancer among women in Shanghai. Effective, appropriate, and affordable breast cancer prevention and control strategies are urgently needed in China.


Subject(s)
Age Factors , Breast Neoplasms/epidemiology , Breast Neoplasms/mortality , Adolescent , Adult , Aged , Aged, 80 and over , Breast Neoplasms/pathology , China/epidemiology , Female , Humans , Middle Aged , Registries , Young Adult
2.
Reprod Sci ; 22(2): 146-55, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25258361

ABSTRACT

RATIONALE: Phenytoin (Dilantin(®); DPH) is used to treat epilepsy but causes estrogen agonist-antagonist-like side effects. We investigated the interaction of phenytoin with estrogen receptors (ERs) α and ß by computational molecular docking, ER competition binding, transcriptional assays, and biological actions, comparing outcomes with estradiol (E2), estrone (E1), and tamoxifen (TMX). EXPERIMENTAL: (1) The DPH docking to 3-dimensional crystal structures of the ERα ligand-binding domain (LBD) showed a high degree of structural complementarity (-57.15 calculated energy units, approximating kcal/mol) with the ligand-binding pocket, including a contact at leucine (L540) in helix 12. Estrogen receptor ß showed slightly less favorable interactions (-54.27 kcal/mol), without contacting L450. Estradiol, E1, and TMX contact points with ERα and ERß do not include L450. (2) Cellular actions: Incubation of cells transfected with ERα or ERß and a luciferase promoter phenytoin was several orders weaker than E2 as an agonist through ERα and had no effect through ERß. However, phenytoin at clinical concentrations (10(-11) to 10(-6) mol/L) powerfully antagonized action of E2 on ERα-expressing cells. Similarly, phenytoin at clinically effective concentrations marginally induced alkaline phosphatase by ERα- and ERß-expressing endometrial cancer cells but at doses well below clinical effectiveness blocked E2-induced alkaline phosphatase. (3) ER competition: In Scatchard plots comparing phenytoin with 17ß-estradiol against endometrial cancer cell cytosol E2-alone more effectively displaced labeled E2 than phenytoin, but phenytoin was approximately equimolar effective to E2 in inhibiting E2's displacement of the radiolabel, further confirming that phenytoin is a strong E2 antagonist. CONCLUSIONS: At clinically effective concentrations, phenytoin is a strong ERα cell antagonist but a many-fold weaker agonist. Although it interacts with ERß LBD residues, phenytoin has no effects on ERß-only expressing cells. Docking studies indicate phenytoin interacts with the ERα LBD at the hinge of helix 12 and could thereby interfere with the entry of other ER ligands or with the mobility of helix 12, either of which actions could explain phenytoin's antagonism of ER-mediated E2 actions. Our results suggest an explanation for the broad profile of phenytoin's actions and raise possibilities for the use of phenytoin or congeners in the clinical management of ERα-dependent conditions.


Subject(s)
Anticonvulsants/pharmacology , Estrogen Receptor alpha/drug effects , Phenytoin/pharmacology , Selective Estrogen Receptor Modulators/pharmacology , Amino Acid Sequence , Anticonvulsants/chemistry , Anticonvulsants/metabolism , Binding Sites , Binding, Competitive , Crystallography , Dose-Response Relationship, Drug , Estradiol/metabolism , Estradiol/pharmacology , Estrogen Receptor alpha/genetics , Estrogen Receptor alpha/metabolism , Estrogen Receptor beta/drug effects , Estrogen Receptor beta/genetics , Estrogen Receptor beta/metabolism , Estrone/metabolism , Estrone/pharmacology , Gene Expression Regulation , Genes, Reporter , Humans , MCF-7 Cells , Molecular Docking Simulation , Molecular Sequence Data , Phenytoin/chemistry , Phenytoin/metabolism , Protein Binding , Protein Structure, Secondary , Selective Estrogen Receptor Modulators/chemistry , Selective Estrogen Receptor Modulators/metabolism , Tamoxifen/metabolism , Tamoxifen/pharmacology , Transcription, Genetic , Transfection
3.
Br J Cancer ; 109(3): 751-5, 2013 Aug 06.
Article in English | MEDLINE | ID: mdl-23860524

ABSTRACT

BACKGROUND: Studies of anthropometric measures and ovarian cancer risk have predominantly included women of European descent with mixed findings. METHODS: Data from the prospective Shanghai Women's Health Study (SWHS) were used to evaluate associations between anthropometric measures and risk of epithelial ovarian cancer (EOC). Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated by Cox proportional hazards regression. RESULTS: A total of 152 EOC cases occurred among 70 258 women. Increasing quartiles of weight, hip circumference, and weight gain during adulthood were associated with significantly increased EOC risks. Body mass index (BMI) was also associated; overweight (25BMI<29.99) and obese women (BMI30.0) had significantly increased risks (HR: 1.49, 95% CI: 1.05, 2.13, and HR: 2.42, 95% CI: 1.37, 4.28, respectively). No significant associations were observed for height, waist circumference, waist-to-hip ratio (WHR), and waist-to-height ratio (WHER). CONCLUSION: Results from this large prospective study of Chinese women support the hypothesis that general adiposity contributes to the aetiology of ovarian cancer.


Subject(s)
Adiposity , Neoplasms, Glandular and Epithelial/epidemiology , Ovarian Neoplasms/epidemiology , Adult , Aged , Anthropometry , Body Mass Index , Body Weight , Carcinoma, Ovarian Epithelial , China/epidemiology , Cohort Studies , Female , Humans , Middle Aged , Neoplasms, Glandular and Epithelial/etiology , Obesity/epidemiology , Ovarian Neoplasms/etiology , Overweight/epidemiology , Proportional Hazards Models , Prospective Studies , Risk Factors
4.
Hum Reprod ; 28(4): 1135-43, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23406970

ABSTRACT

STUDY QUESTION: Do genetic polymorphisms which influence age at menarche in women of European ancestry also influence women of Chinese ancestry? SUMMARY ANSWER: Many genetic variants influencing age at menarche in European populations appear to impact Chinese populations in a similar manner. WHAT IS KNOWN AND WHAT THIS PAPER ADDS: Prior genome-wide association studies have uncovered 42 SNPs associated with age at menarche in European populations. This study is the first to demonstrate that many of the genetic determinants of age at menarche are shared between European and Chinese women. PARTICIPANTS AND SETTING: We evaluated 37 of 42 SNPs identified as associated with age at menarche from a recent, large meta-analysis, consisting primarily of women of European ancestry, in a population of 6929 Chinese women from Shanghai, China. We also constructed weighted genetic risk scores (GRSs) combining the number of effect variants for all 37 SNPs, or only the SNPs associated with age at menarche among our study population, to evaluate their joint influence on age at menarche. MAIN RESULTS: For 32 of the 37 evaluated variants, the direction of the allele associations were the same between women of European ancestry and women of Chinese ancestry (P = 3.71 × 10(-6), binomial sign test); 9 of these were statistically significant. Subjects in the highest quintile of GRSs began menarche ∼5 months later than those in the lowest quintile. BIAS, LIMITATIONS AND GENERALIZABILITY TO OTHER POPULATIONS: Age at menarche was obtained by self-report, which can be subject to recall errors. The current analysis was restricted to loci which met or approached GWAS significance thresholds and did not evaluate loci which may act predominantly or exclusively in the Chinese population. The smaller sample size for our meta-analysis compared with meta-analyses conducted in European populations reduced the power to detect significant results. STUDY FUNDING/COMPETING INTERESTS: This study was supported, in part, by grants from US National Institutes of Health (grants R01CA124558, R01CA090899, R01CA070867; R01CA064277 and R01CA092585 and UL1 RR024975), Ingram professorship funds and Allen Foundation funds. There are no competing interests to declare.


Subject(s)
Asian People/genetics , Genome-Wide Association Study , Menarche/genetics , Polymorphism, Single Nucleotide , White People/genetics , Adolescent , Adult , Age Factors , China , Female , Humans
5.
Reprod Sci ; 20(8): 917-28, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23344457

ABSTRACT

INTRODUCTION: Intrauterine growth restriction (IUGR) has been associated with exposure to polyaromatic hydrocarbons (PAHs) which are released in the combustion of oil, fuel, gas, garbage, and tobacco. Pregnant women exposed to PAHs are at risk of the effects of these environmental toxins; for example, benzo-α-pyrene (BαP) is able to enter the blood stream and could contribute to IUGR or other developmental abnormalities via effects on the placental cells. Since IUGR has been associated with decreased cord blood concentrations of immunoreactive insulin-like growth factor 1 (ir-IGF-1) and IUGR has been associated with disordered development and fetal programming, we tested the effects of BαP on human placental trophoblast cells in culture. EXPERIMENTAL: IGF-1 expression and activation was studied using an immortalized human placental trophoblast cell line (HTR-8). The cells were treated with vehicle control or 1 µmol/L BαP, or 5 µmol/L BαP for 12 hours. RNA was extracted and the exons of IGF-1 were amplified using reverse transcriptase-polymerase chain reaction (RT-PCR). The ir-IGF-1 expression levels were compared using gel electrophoresis. The PCR products were sequenced, and levels of mutation were measured with comparative sequence analysis. A computational protein analysis (computer simulation) was performed in order to assess the potential impact of BαP-associated mutation on IGF-1 protein function. RESULTS: The IGF-1 expression decreased considerably in BαP-treated cells relative to untreated controls (P < .05), also in a dose-dependent manner. Comparative sequence analysis indicated that the level of BαP exposure correlated with the percentage of base pair mutations in IGF-1 nucleotide sequences for both treatment groups (P < .05). Shifts were observed in the open reading frame, indicating a possible change in the IGF-1 start codon. Protein folding simulation analysis indicated that the base pair changes induced by BαP weakened IGF-1-IGF binding protein (IGFBP) interaction. CONCLUSIONS: In concordance with the previous findings, exposure of human placental trophoblast cells to BαP exposure results in reduction of IGF-1 expression and base pair mutations. The direct action of BαP on the placenta indicates that it may not be necessary for BαP to access other maternal tissues in order for gene abnormalities to occur. Given that PAHs are known to work through aryl hydrocarbon hydrolase (AHH), these results are likely due to the presence of AHH in HTR cells. Computational modeling of BαP actions on IGF1, substrate-ligand binding, supports the biological premise of this work and underlines the need to determine actual biological effects rather than equating immune to bioactivity of IGF1.


Subject(s)
Benzo(a)pyrene/toxicity , Computational Biology , Environmental Pollutants/toxicity , Insulin-Like Growth Factor I/drug effects , Trophoblasts/drug effects , Amino Acid Sequence , Base Sequence , Cell Line , Codon, Initiator , Computational Biology/methods , Computer Simulation , DNA Mutational Analysis , Dose-Response Relationship, Drug , Down-Regulation , Female , Humans , Insulin-Like Growth Factor Binding Proteins/metabolism , Insulin-Like Growth Factor I/genetics , Insulin-Like Growth Factor I/metabolism , Models, Molecular , Molecular Sequence Data , Mutagenesis , Mutation , Open Reading Frames , Pregnancy , Protein Folding , Protein Interaction Domains and Motifs , Protein Interaction Mapping , RNA, Messenger/metabolism , Risk Assessment , Trophoblasts/metabolism , Trophoblasts/pathology
6.
Hum Reprod ; 23(9): 2104-12, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18552365

ABSTRACT

BACKGROUND: Ezrin protein and its activated form phospho-ezrin play a role in cell morphology, motility and adhesiveness. In this study, we hypothesized that these proteins play a role in the pathogenesis of endometriosis by promoting adhesion and invasion of endometrial stromal cells (ESCs) in ectopic sites. METHODS: We compared the expression of ezrin and phospho-ezrin in normal endometrium from women without endometriosis with their expression in eutopic and ectopic endometrial tissues from women with endometriosis, using immunohistochemistry and western blot analysis. Paired eutopic and ectopic endometrial tissue samples from women with endometriosis (n = 13) and normal endometrium from women without endometriosis (n = 12) were collected. Invasive potential of ESCs from each of these samples was compared using Matrigel membrane invasion assay. RESULTS: Eutopic and ectopic endometrial tissues from women with endometriosis have higher ezrin and phospho-ezrin levels as confirmed by immunohistochemistry and western blot analysis (P < 0.05). The Matrigel membrane invasion assay revealed that ectopic ESCs have more invasive characteristics, more protrusions and higher ezrin staining than normal ESCs (P < 0.05). CONCLUSIONS: Ezrin can be a potential marker for endometrial cell invasion and may play a role in the pathogenesis of endometriosis.


Subject(s)
Cytoskeletal Proteins/metabolism , Endometriosis/metabolism , Adult , Blotting, Western , Case-Control Studies , Cell Adhesion , Endometriosis/pathology , Endometrium/metabolism , Endometrium/pathology , Female , Humans , Immunohistochemistry , Middle Aged , Phosphorylation , Stromal Cells/metabolism , Stromal Cells/pathology
7.
Maturitas ; 60(1): 31-41, 2008 May 20.
Article in English | MEDLINE | ID: mdl-18486367

ABSTRACT

OBJECTIVE: The vagina is a complex tubular structure that has reproductive, support and barrier functions. These depend on the cytoarchitecture of the vaginal cells, which is controlled by key proteins. Cytoskeletal proteins determine cell polarity and membrane specializations by integrating the actin cytoskeleton with cell membranes. This integration is the domain of cytoskeletal proteins including the MERM protein family (moesin-ezrin-radixin-Merlin). Nothing is known about the cyto-localization of the MERM's in the vaginal epithelium or how it influences the cytoarchitecture of the vaginal epithelium and stroma. DESIGN: Full-thickness human vaginal fornix samples were obtained from 20 normal human specimens obtained at surgery for pelvic relaxation. Light- and electron microscopical immunohistochemistry (IHC) were used to identify and study activation and cellular localization of immuno-reactive-ezrin (ir-ezrin), a prototypical MERM. RESULTS: Ir-ezrin was identified in the stratified squamous vaginal epithelium and connective tissue (fibroblasts, blood vessels and leucocytes). "H" scoring indicated that ir-ezrin staining is denser in the vaginal epithelium than in other layers, that the ir-ezrin staining was associated with increased keratinization and with the size of the tight junctions (p<0.01). Both the amounts and localization of ir-ezrin were associated with high levels of estrogen, identified by the menstrual history and keratinization of the superficial vaginal epithelium. The density of stromal ir-ezrin was increased in the presence of dense epithelial keratinization. Immuno-reactive-ezrin staining was most pronounced near the cell membranes of both keratinized and non-keratinized epithelium, indicating that ezrin activation (unfolding and movement to the membrane) had occurred. Ultra-structural examination of the epithelium showed intra-cellular ir-ezrin to be localized to junctional complexes that have been associated with decreased mucosal penetration by microorganisms. Ir-ezrin was widely distributed throughout stromal fibro-muscular cell, vessels and immunocytes. CONCLUSIONS: MERM's, represented by ezrin, are widely present in the vaginal wall. This has implications for the strength and resilience of this tubular structure and may be the case in other internal genital tissues. Ezrin's localization and association with cell specializations indicate that in the vagina, as in other tissues, ezrin likely modulates vaginal cell-cell interactions including the changing vaginal cellular interface with the external environment, the regulation of the elasticity of the vagina, and the regulation of microbial and chemical traffic that determine the pH and microbial environment of the vagina. In other work we have shown that ezrin expression is induced by estradiol. The increase of ir-ezrin staining during the appearance of keratinization and maturation of the vaginal cytology indicates that estrogen may regulate vaginal ezrin and thereby the properties of the vaginal wall and epithelium.


Subject(s)
Cytoskeletal Proteins/metabolism , Vagina/cytology , Vagina/metabolism , Adult , Cell Communication/physiology , Cytoskeleton/metabolism , Cytoskeleton/ultrastructure , Elasticity , Epithelial Cells/cytology , Epithelial Cells/metabolism , Epithelial Cells/ultrastructure , Estrogens/physiology , Female , Humans , Middle Aged , Vagina/ultrastructure
8.
Biosci Hypotheses ; 1(5): 255-257, 2008.
Article in English | MEDLINE | ID: mdl-19129921

ABSTRACT

We report an interesting finding that cellular distribution and interactions between neighboring cells modulate protein expression and localization. MCF7 breast cancer cells, which express ERb, were cultured in estrogen free medium. ERb exhibited a unique migration pattern that was dependent on cell density and proximity. This findings attest to a novel mechanism other than ligand-receptor one. Since cells were grown in conditioned culture media, the only factor influencing protein distribution is cell-cell proximity (cell-cell interactions). Thus, hormonal receptors may function independently from their ligand. in addition, physical intercellular interactions may function as a non-molecular factor inducing gene expression and activation.

9.
Med Hypotheses ; 67(5): 1095-8, 2006.
Article in English | MEDLINE | ID: mdl-16824698

ABSTRACT

Merlin and ezrin proteins belong to the same gene family, i.e., MERM containing merlin, ezrin radixin and moesin. Members of this family possess an extensive homology in their amino acid sequences. It has been shown that merlin is a tumor suppressor, while ezrin is a promoter in tumor progression. The expression of these two proteins is commonly found inversely proportional to each other in cancer cells, i.e. down-regulation of merlin concomitant with over-expression of ezrin and vice versa. However, when determining merlin and ezrin in ovarian carcinoma cells, we have observed that both merlin and ezrin could be over-expressed simultaneously in some ovarian cancer (OVCA) cell lines and OVCA ascites cells, suggesting that merlin could be an oncoprotein rather than a tumor suppressor protein in certain OVCA cells. The functional duality of merlin might represent a paradigm in proteome complexity and is especially important in investigating multifactorial diseases such as cancer.


Subject(s)
Neoplasms/genetics , Neurofibromin 2/genetics , Cell Line, Tumor , Cytoskeletal Proteins/genetics , Cytoskeletal Proteins/physiology , Down-Regulation , Female , Humans , Membrane Proteins/genetics , Neoplasm Metastasis/genetics , Neoplasms/pathology , Neoplasms/physiopathology , Neurilemmoma/genetics , Neurofibromin 2/physiology , Ovarian Neoplasms/genetics , Phosphorylation , Tumor Suppressor Proteins/genetics
10.
J Biomol Struct Dyn ; 23(4): 457-64, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16363880

ABSTRACT

Identifying and predicting the structural characteristics of novel repeats throughout the genome can lend insight into biological function. Specific repeats are believed to have biological significance as a function of their distribution patterns. We have developed 'GenomeMark,' a computer program that detects and statistically analyzes candidate repeats. Specifically, 'GenomeMark' identifies the periodic distribution of unique words, calculating their chi2 and Z-score values. Using 'GenomeMark,' we identified novel sequence words present in tandem throughout genomes. We found that these sequences have remarkable spacer sequence distributions and many were genome specific, validating the genome signature theory. Further analysis confirmed that many of these sequences have a specific biological function. The program is available from the authors upon request and is freely available for non-commercial and academic entities.


Subject(s)
Repetitive Sequences, Nucleic Acid , Software , Algorithms , Archaea/genetics , Bacteria/genetics , Genomics/statistics & numerical data , Markov Chains , Sequence Analysis, DNA/statistics & numerical data
11.
Protein Pept Lett ; 12(6): 499-506, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16101385

ABSTRACT

Scientists from over 20 major research centers recently convened to discuss advances and new discoveries in "Protein MisFolding and MisProcessing in Disease." Understanding protein mechanisms the underlying etiology of complex diseases lies in analyzing the associated biochemical mechanisms, which include folding patterns, processing patterns, chaperone regulators, stress pathways, and signal transduction.


Subject(s)
Disease , Protein Folding , Protein Processing, Post-Translational , Proteins/chemistry , Proteins/metabolism , Animals , Endoplasmic Reticulum/metabolism , Humans , Therapeutics
12.
Med Hypotheses ; 65(5): 956-61, 2005.
Article in English | MEDLINE | ID: mdl-16054303

ABSTRACT

Circulation cell free DNA (cf-DNA) is of considerable interest to oncology researchers seeking to isolate specific cancer markers. Here, we focus on the origin and biological implications of cf-DNA, exploring its potential roles in cancer biology and medicine. We hypothesize that cf-DNA is primarily released by living cancer cells in addition to apoptotic or necrotic cancer cells for three reasons: (1) following radiotherapy, cf-DNA quantities are significantly reduced in a high percentage of patients although radiation-induced massive apoptosis is expected; (2) cancer cell DNA concentration in cultured supernatants increases with cell proliferation when few apoptotic or necrotic cells are present; and (3) DNA concentration increases in normal lymphocyte cultures following stimulation with phytohemagglutinin, lipopolysaccharide or antigen. Our hypotheses have major biological implications in cancer biology. First, cancer cf-DNA may transform normal cells and form adjacent or remote metastases or second primary cancer. In this context, we also have raised an alarming advice that the cancer may be potentially infectious. Secondly, if a normal cf-DNA contains cytokine sequence, it may behave like an intrinsic DNA vaccine, producing therapeutic cytokine. If normal cf-DNA contains a sequence of a non-mutated oncogene or tumor suppressor gene, homologous recombination with the cancer genome may occur leading to knock out mutated oncogene or tumor suppressor gene that could thus elicit a spontaneous remission of cancer.


Subject(s)
Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/immunology , DNA, Neoplasm/blood , Neoplasm Metastasis/genetics , Neoplasm Metastasis/immunology , Neoplasms/genetics , Neoplasms/immunology , Animals , Apoptosis/genetics , DNA Fragmentation/genetics , DNA Fragmentation/immunology , Humans , Models, Biological , Neoplasms/blood , T-Lymphocytes/immunology , Transfection/methods , Transformation, Genetic/genetics , Transformation, Genetic/immunology
13.
Lett Appl Microbiol ; 40(1): 12-8, 2005.
Article in English | MEDLINE | ID: mdl-15612996

ABSTRACT

AIMS: Researchers have long been puzzled by the diversity of life. Now that the complete genomic sequence of many organisms has been determined, it is possible to evaluate the impact of organismal variation on sequence structure or vice versa. The aim of this investigation was to explore genomic changes mandated by organismal adaptation to its ecological niches. METHODS AND RESULTS: Coding sequences from three phylogenetically related bacterial species namely Mycoplasma genitalium, M. pneumoniae and Ureaplasma urealyticum were subject to in depth sequence analyses. M. genitalium and M. pneumoniae both belong to the genus Mycoplasma while U. urealyticum is a member of the genus Ureaplasma. However, M. genitalium and U. urealyticum are urogenital pathogens while M. pneumoniae is a respiratory pathogen. Complete transcriptomes were downloaded from NCBI for each species, and were subject to in silico investigation using in-house software, and public sequence analysis tools. Clear similarities in transcriptome structure were identified among the functionally similar species M. genitalium and U. urealyticum while no such relationship was identified among the phylogenetically related species M. genitalium and M. pneumoniae. CONCLUSIONS: It is plausible to conclude that, in these bacterial species, environmental stimuli might be more influential in shaping sequence signatures than phylogenetic relationships. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests that molecular signatures within the transcriptomes of the species examined are likely to be a product of evolutionary adaptation to diverse environmental ecological stimuli, and not a result of common phylogeny.


Subject(s)
Adaptation, Biological , Codon/genetics , Genome, Bacterial , Mycoplasma/genetics , Amino Acid Sequence , Base Composition , Databases as Topic , Evolution, Molecular , Genomics , Open Reading Frames/physiology , Phylogeny , Sequence Homology, Amino Acid
14.
J Egypt Soc Parasitol ; 34(1): 65-82, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15125517

ABSTRACT

Parasites affect a majority of the world's population. Despite this fact, dreams of developing vaccines remain far off. Scientists have long studied gene expression as a hallmark of gene activities reflecting current cell conditions. Analyzing differentially expressed genes is a major initiative, and most labs recoil at the amount of time and high costs required obtaining results. By employing microarrays, researchers can decrease their reliance upon time consuming techniques; consequently, microarray is beginning to dominate other molecular diagnostic technologies. Moreover, the ability of microarrays to monitor simultaneous gene expression of thousands of genes and to produce broad arrays of data has the potential to shift the resources of the scientists from data gathering to analyzing data that are already available. As microarray technology improves and its cost decreases, the role of ability to "see" the molecular biology pathways involved in parasite host relationships will place this technology at the forefront of parasite research.


Subject(s)
Gene Expression Profiling , Oligonucleotide Array Sequence Analysis , Parasitic Diseases/diagnosis , Animals , Gene Expression Profiling/veterinary , Humans , Oligonucleotide Array Sequence Analysis/veterinary , Sensitivity and Specificity , Time Factors
15.
J Egypt Soc Parasitol ; 32(2): 625-38, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12214939

ABSTRACT

Patterns of codon usage and bias were characterized in the genus Ascaris. Furthermore, the influence of base composition and intercodon frequencies on codon usage was investigated using freely available analytical software. Results showed that A and T were present in the genome at a higher frequency than G and C. As well, codons with AT base pairs at the wobble position were used more often than those with GC at this site, suggesting that the bias extends to the codon level. The presence of T at the intercodon position inhibited the use of codon with A at the wobble site. With respect to amino acid frequency, Serine, Leucine, and Arginine accounted for a disproportionately large fraction of the overall amino acid distribution per gene, implying that the bias was also conserved at the protein level.


Subject(s)
Ascaris/genetics , Codon , Amino Acids/analysis , Animals , Base Composition , Base Sequence , Codon/chemistry
16.
J Egypt Soc Parasitol ; 32(2): 657-73, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12214942

ABSTRACT

Parametric analyses were used to investigate the nucleotide, codon, and amino acid composition of coding sequences corresponding to hook-worms. Ancylostoma caninum and Necator americanus. Although genomic research has become prevalent within the scientific community, few studies have dealt directly with parasitic species. Parasites have existed throughout the history of mankind due to their wide range of distribution in nature and their ability to evade immune detection. An AT nucleotide bias was identified in both A. caninum and N. americanus sequences. A similar AT bias was also identified in both datasets when considering relative synonymous codon usage. However, the codon bias was much more pronounced in N. americanus as compared to A. caninum. Bias was also present at the amino acid level, and appeared to be partially independent of the nucleotide-based biases. Analysis of parasite genomes will facilitate the development of vaccines against larval forms of parasites. Moreover, the examination of the parasite genes in general, will allow for a more in-depth understanding of the evolution of the parasites and parasitism.


Subject(s)
Ancylostoma/genetics , Codon , Necator americanus/genetics , Ancylostoma/classification , Animals , Base Composition , Base Sequence , Codon/chemistry , DNA, Complementary/chemistry , Necator americanus/classification , Phylogeny
17.
Cancer ; 92(12): 3068-75, 2001 Dec 15.
Article in English | MEDLINE | ID: mdl-11753986

ABSTRACT

BACKGROUND: Ezrin is a member of the ezrin, radixin, and moesin family. These proteins are membrane-actin cross-linking proteins. Furthermore, ezrin is an important signal transduction protein that undergoes phosphorylation and translocation on stimulation by growth factors. Ezrin phosphorylation and translocation are thought to be correlated with cell motility, invasion, and carcinoma metastasis. Recently, the authors reported that an ezrin antisense phosphorothionate could significantly inhibit endometrial carcinoma cells' penetration in the Matrigel membrane cancer invasion assay. In the current study, the authors measured ezrin content in clinical ovarian epithelial carcinoma (OVCA) specimens and cell lines and investigated whether interleukin (IL)-1alpha and epidermal growth factor (EGF) induce an invasive phenotype in OVCA cells via ezrin phosphorylation and translocation. METHODS: Twenty-five normal ovary, 25 primary OVCA, 21 metastatic OVCA tissue (7 in omentum, 16 in ascites), and 3 OVCA cell lines were collected for Western blot detection of ezrin content. The OVCA cell line SKOV3 was treated with IL-1alpha or EGF. Indirect immunofluorescence staining followed by confocal laser scanning and double-staining electron microscopic immunohistochemistry were used to investigate changes in the intracellular distribution of ezrin and cell morphology after IL-1alpha or EGF treatment. The content of ezrin was measured by Western blotting and analyzed by the National Institutes of Health Image computer program. Immunoprecipitation and Western blot techniques were used for ezrin phosphorylation studies. Genistein was used to block tyrosine phosphorylation. RESULTS: (1) Ezrin was overexpressed in OVCA, with the highest values in metastases. (2) Interleukin-1alpha and EGF significantly increased OVCA tyrosine phosphorylation, ezrin translocation, and cell growth. (3) These effects were abolished by treatment with the tyrosine kinase inhibitor, genistein. (4) Treatment with IL-1alpha or EGF induced an invasive phenotype, i.e., membrane ruffling, and process formation. CONCLUSIONS: High expression and activation of ezrin appear to be related to OVCA metastatic behavior. Interleukin-1alpha and EGF may regulate OVCA invasive behavior by activating ezrin tyrosine phosphorylation, translocation, and cancer cell proliferation. The authors' results may partially explain why OVCA patients with positive macrophage colony stimulating factor (a chemoattractant of IL-1alpha secreting monocytes) or EGF receptors (c-erb B-2) have a poor prognosis.


Subject(s)
Carcinoma/physiopathology , Cell Division , Epidermal Growth Factor/pharmacology , Gene Expression Regulation, Neoplastic , Interleukin-1/pharmacology , Neoplasm Invasiveness , Ovarian Neoplasms/physiopathology , Phosphoproteins/genetics , Translocation, Genetic , Tyrosine/metabolism , Blotting, Western , Cytoskeletal Proteins , Female , Humans , Immunohistochemistry , Neoplasm Metastasis , Phenotype , Phosphoproteins/metabolism , Phosphoproteins/pharmacology , Phosphorylation , Tumor Cells, Cultured
18.
Genomics ; 74(2): 197-210, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11386756

ABSTRACT

Base frequency, codon usage, and intercodon identity were analyzed in five filarial parasite species representing five Onchocercidae genera. Wucheria bancrofti, Brugia malayi, Onchocerca volvulus, Acanthocheilonema viteae, and Dirofilaria immitis gene sequences were downloaded from NCBI, and analysis was performed using locally designed computer programs and other freely available applications. A clear sequence bias was observed among the nematode species examined. At the nucleotide level, AT basepairs were present in gene sequences at higher frequencies than GC. In addition, codons ending in A or T were used proportionately more than those with G or C in the third-codon position. In addition, the amino acids used most often corresponded to codons ending in AT basepairs. Intercodon base proportion was biased in that A was found most often at N4, second only to T in certain specific cases. Since all of these sequence biases were observed in a relatively consistent fashion among all of the organisms studied, we conclude that sequence bias is a genetic characteristic, which is associated with multiple filarial genera.


Subject(s)
Codon , Filarioidea/genetics , Animals , Brugia/genetics , Databases, Factual , Dirofilaria/genetics , Genetic Variation , Onchocerca/genetics , Species Specificity , Wuchereria/genetics
19.
Cancer ; 85(12): 2616-22, 1999 Jun 15.
Article in English | MEDLINE | ID: mdl-10375110

ABSTRACT

BACKGROUND: This study was conducted to evaluate whether estramustine (estrogen mustard [EM]) is a promising alternative in the treatment of patients with epithelial ovarian carcinoma (OVCA). EM is a microtubule-associated protein (MAP) specific antimicrotubule agent with low toxicity. METHODS: The authors investigated the ability of EM to induce apoptosis and suppress colony formation of OVCA cells. Paclitaxel was used as a positive control. DNA electrophoresis and terminal deoxynucleotidyl dUTP-X nick end labeling (TUNEL) assays were used to detect internucleosomal DNA fragmentation. Flow cytometry was used to identify apoptotic cells and disturbance of the cell cycle of EM-treated OVCA cells further. Quantitation of detached cultured cells also provided a relative estimate of the apoptotic response of OVCA cells to treatment with EM. The colony formation assay was used to evaluate the effects of EM on clonogenicity. RESULTS: The effects of EM on four OVCA cell lines in culture were highly similar to those of paclitaxel in causing apoptosis and inhibiting clonogenicity. DNA electrophoresis and TUNEL assays showed that EM induced internucleosomal DNA fragmentation in OVCA cells. Flow cytometry showed changes typical of apoptotic changes and cell cycle block and synchronization at the G2/M-phase. Counting of detached cells showed a log-dose response to EM treatment. The colony formation assay also showed a log-dose response suppression of OVCA cell clonogenicity after treatment with EM. CONCLUSIONS: EM may be a promising candidate in the clinical treatment of patients with OVCA. The lower toxicity and MAP specific action of EM is a novel chemotherapy for OVCA.


Subject(s)
Antineoplastic Agents, Alkylating/pharmacology , Apoptosis/drug effects , Carcinoma/pathology , Estramustine/pharmacology , Ovarian Neoplasms/pathology , Female , Humans , In Situ Nick-End Labeling , Paclitaxel/pharmacology , Tumor Cells, Cultured/drug effects , Tumor Stem Cell Assay
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