Expression Of COMT Research Articles

Regulation of cancer-related genes - Cyp1a1, Cyp1b1, Cyp19, Nqo1 and Comt - expression in β-naphthoflavone-treated mice by miroestrol.

The effects of miroestrol (MR), an active phytoestrogen from Pueraria candollei var. mirifica, on expression of cancer-related genes were determined. Seven-week-old female ICR mice (n = 5 each) were subcutaneously administered estradiol (E2, 0.5 mg/kg/day) or MR (0.5 or 5 mg/kg/day) daily for 7 days. Some were given ER or MR in combination with β-naphthoflavone (BNF, 30 mg/kg/day) for the last 3 days. The expression of cancer-related genes including cytochrome P450 1A (Cyp1a), cytochrome P450 1B1 (Cyp1b1), aromatase P450 (Cyp19), NAD(P)H: quinone oxidoreductase 1 (Nqo1) and catechol-O-methyltransferase (Comt) were evaluated. In the presence of BNF, MR suppressed hepatic CYP1A1 activity and CYP1A2 activity, expression of CYP1B1 mRNA and expression of CYP1A1/2 and CYP1B1 protein. E2, by contrast, did not. MR restored expression levels of hepatic NQO1 and uterine COMT in BNF-treated mice. Furthermore, MR increased expression of uterine CYP19 to the same extent as E2. MR may be superior to E2 as it downregulates expression of CYP1. Moreover, MR normalized expression of both NQO1 and COMT, the protective enzymes, in murine liver and uteri. These results support the use of MR as an alternative supplement for menopausal women, MR having the extra benefit of reducing cancer risk.

Changes in the Expression of Dopaminergic Genes in Brain Structures of Male Mice Exposed to Chronic Social Defeat Stress: An RNA-seq Study

Whole-transcriptome analysis (RNA-seq) has been used to analyze changes in the expression of dopaminergic genes that encode proteins involved in the synthesis, inactivation, and neurotransmission of dopamine in the striatum, ventral tegmental area, raphe nuclei of the midbrain, hypothalamus, and hippocampus of male mice subjected to chronic social defeat. The expression of Th, Ddc, and Slc6A3 (Dat1) was upregulated, while that of Ppp1r1b and Sncg was downregulated in the ventral tegmental area; the expression of Th, Ddc, Drd2, and Sncg was downregulated in the raphe nuclei of midbrain; the expression of Th, Aldh2, and Ppp1r1b was upregulated, while that of Маоа was downregulated in the hypothalamus; Drd1 and Snca expression was downregulated and that of Sncb was upregulated in the striatum, and Sncb expression was upregulated in the hippocampus. There were no statistically significant changes in the expression of Comt, Maob, Drd3, Drd4, or Drd5 in the brain areas analyzed in stressed male mice (compared to control animals). Thus, the number of differentially expressed dopaminergic genes and the direction of expression changes in male mice experiencing chronic stress are specific to regions of the brain.

Depression, Cytokine, and Cytokine by Treatment Interactions Modulate Gene Expression in Antipsychotic Naïve First Episode Psychosis.

In schizophrenia, genetic and environmental factors affect neurodevelopment and neuroprogressive trajectory. Altered expression of neuro-immune genes and increased levels of cytokines are observed, especially in patients with comorbid depression. However, it remains unclear whether circulating levels of cytokines and expression of these genes are associated, and how antipsychotic treatments impact this association. Relationships between messenger RNA (mRNA) expression of 11 schizophrenia-related genes and circulating levels of cytokines (interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α) were analyzed in 174 antipsychotic naïve first episode psychosis (FEP) and in 77 healthy controls. A subgroup of 72 patients was reassessed after treatment with risperidone. FEP patients were divided into those with and without depression. FEP patients with depression showed increased COMT expression and decreased NDEL1 expression. Increased IL-6 was associated with lowered AKT1 and DROSHA expression, while increased IL-10 was associated with increased NDEL1, DISC1, and MBP expression. IL-6 levels significantly increased the risperidone-induced expression of AKT1, DICER1, DROSHA, and COMT mRNA. The differential mRNA gene expression in FEP is largely associated with increased cytokine levels. While increased IL-6 may downregulate AKT-mediated cellular functions and dysregulate genes involved in microRNA (miRNA) machinery, increased IL-10 has neuroprotective properties. Increased IL-6 levels may prime the expression of genes (AKT1, DICER1, DROSHA, and COMT) in response to risperidone, suggesting that cytokine × treatment × gene interactions may improve cell function profiles. FEP patients with depression show a different gene expression profile reinforcing the theory that depression in FEP is a different phenotype.

Postnatal neurodevelopmental expression and glutamate-dependent regulation of the ZNF804A rodent homologue

The zinc finger protein ZNF804A rs1344706 variant is a replicated genome-wide significant risk variant for schizophrenia and bipolar disorder. While its association with altered brain structure and cognition in patients and healthy risk allele carriers is well documented, the characteristics and function of the gene in the brain remains poorly understood. Here, we used in situ hybridization to determine mRNA expression levels of the ZNF804A rodent homologue, Zfp804a, across multiple postnatal neurodevelopmental time points in the rat brain. We found changes in Zfp804a expression in the rat hippocampus, frontal cortex, and thalamus across postnatal neurodevelopment. Zfp804a mRNA peaked at postnatal day (P) 21 in hippocampal CA1 and DG regions and was highest in the lower cortical layers of frontal cortex at P1, possibly highlighting a role in developmental migration. Using immunofluorescence, we found that Zfp804a mRNA and ZFP804A co-localized with neurons and not astrocytes. In primary cultured cortical neurons, we found that Zfp804a expression was significantly increased when neurons were exposed to glutamate [20μM], but this increase was blocked by the N-methyl-d-aspartate receptor (NMDAR) antagonist MK-801. Expression of Comt, Pde4b, and Drd2, genes previously shown to be regulated by ZNF804A overexpression, was also significantly changed in an NMDA-dependent manner. Our results describe, for the first time, the unique postnatal neurodevelopmental expression of Zfp804a in the rodent brain and demonstrate that glutamate potentially plays an important role in the regulation of this psychiatric susceptibility gene. These are critical steps toward understanding the biological function of ZNF804A in the mammalian brain.

The effect of chronic gamma ray irradiation on lignocellulose of Brachypodium distachyon

The effects of chronic gamma ray irradiation on Brachypodium distachyon were investigated to lignocellulose composition and enzymatic hydrolysis. Four-week-old plants of B. distachyon were exposed to gamma-ray irradiation at doses of 50, 100, 150, 200, 250, and 300 Gy. Gamma-ray irradiation negatively influenced biomass related morphology including plant height and cell size; however, it increased tiller number and internode diameter. SEM image analysis showed that the cell size of 300-Gy gamma irradiated plants was 45 % lower than that of the control. Destroyed regions on the cell wall surface were observed according to the dose of radiation. Cell wall yield, lignin content, and neutral sugar content were decreased in a dose-dependent manner. Glucose yield via enzymatic hydrolysis was positively correlated with radiation dose. In addition, 250-Gy and 300-Gy irradiated plants showed significantly better saccharification efficiency than non-irradiated controls. Initial glucose yields from 250-Gy- and 300-Gy-irradiated plants were 121.5 and 139.4 % of yields from non-irradiated controls, and final yields were 184.7 and 213.7 % of control yields, respectively. Reverse-transcription polymerase chain reaction (RT-PCR) analysis of lignin pathway-related genes showed increase of F5H, COMT, and CAD expression in 250-Gy- and 300-Gy-irradiated Brachypodium plants. Chemical composition analysis further verified that chronic gamma ray irradiation degraded lignocellulose as a pretreatment.

Molecular genetic mechanisms of allelic specific regulation of murine Comt expression.

A functional allele of the mouse catechol-O-methyltransferase (Comt) gene is defined by the insertion of a B2 short interspersed repeat element in its 3'-untranslated region (UTR). This allele has been associated with a number of phenotypes, such as pain and anxiety. In comparison with mice carrying the ancestral allele (Comt+), Comt B2i mice show higher Comt mRNA and enzymatic activity levels. Here, we investigated the molecular genetic mechanisms underlying this allelic specific regulation of Comt expression. Insertion of the B2 element introduces an early polyadenylation signal generating a shorter Comt transcript, in addition to the longer ancestral mRNA. Comparative analysis and in silico prediction of Comt mRNA potential targets within the transcript 3' to the B2 element was performed and allowed choosing microRNA (miRNA) candidates for experimental screening: mmu-miR-3470a, mmu-miR-3470b, and mmu-miR-667. Cell transfection with each miRNA downregulated the expression of the ancestral transcript and COMT enzymatic activity. Our in vivo experiments showed that mmu-miR-667-3p is strongly correlated with decreasing amounts of Comt mRNA in the brain, and lentiviral injections of mmu-miR-3470a, mmu-miR-3470b, and mmu-miR-667 increase hypersensitivity in the mouse formalin model, consistent with reduced COMT activity. In summary, our data demonstrate that the Comt+ transcript contains regulatory miRNA signals in its 3'-untranslated region leading to mRNA degradation; these signals, however, are absent in the shorter transcript, resulting in higher mRNA expression and activity levels.

Nuclear factor-kappa B regulates pain and COMT expression in a rodent model of inflammation

Nuclear factor-kappa B regulates pain and COMT expression in a rodent model of inflammation

Molecular genetic mechanisms of allelic specific regulation of murine Comt expression

Molecular genetic mechanisms of allelic specific regulation of murine Comt expression

A <i>Comt</i>1 Loss of Function Mutation Is Insufficient for Loss of Pungency in <i>Capsicum</i>

The participation of O-methyltransferase (COMT) in phenylpropanoid-mediated capsaicinoid biosynthesis has long been proposed. Ferulic acid, a phenylpropanoid intermediate, is a precursor of capsaicinoid biosynthesis and is produced from caffeic acid by the action of COMT. As previously reported that silencing Comt expression caused a drastic decrease in capsaicinoid accumulation, it was presumed that a Comt loss-of-function mutation would cause loss of pungency in Capsicum. This hypothesis was tested by cloning Comt1 and Comt2 from the placenta tissue of the pungent cultivar Habanero. The phylogenetic analysis and comparison of critical amino-acid residues for enzyme function showed that the two COMTs had high similarity with the COMTs of other plant species. Moreover, as the two Comts were both expressed in placenta tissue and expressed prior to the accumulation of capsaicinoids, the two genes could be candidates for capsaicinoid biosynthesis. Second, Comt1 loss-of-function mutants were screened from the germplasm. A truncated Comt1 transcript was expressed in non-pungent pepper No.3341 caused by deletion of the genomic region. The predicted No.3341 COMT1 lacked His-265, which was absolutely necessary for enzymatic activity. Contrary to our expectations, the Comt1 mutation was not related to non-pungency of No.3341, as the deletion of Comt1 did not co-segregate with non-pungency in the F2 population obtained from crossing No.3341 with Habanero. This result was confirmed by screening several pungent accessions harboring the same Comt1 deletion mutation. Although the participation of COMT in phenylpropanoid-mediated capsaicinoid biosynthesis has long been proposed, our present study shows that Comt1 can not be a target for controlling fruit pungency.

Cloning and functional characterization of MusaVND1 using transgenic banana plants.

Vascular related NAC (NAM, ATAF and CUC) domain-containing genes regulate secondary wall deposition and differentiation of xylem vessel elements. MusaVND1 is an ortholog of Arabidopsis VND1 and contains the highly conserved NAC domain. The expression of MusaVND1 is highest in developing corm and during lignification conditions, the increase in expression of MusaVND1 coincides with the expression of PAL, COMT and C4H genes. MusaVND1 encodes a nuclear localized protein as MusaVND1-GFP fusion protein gets localized to nucleus. Transient overexpression of MusaVND1 converts banana embryogenic cells to xylem vessel elements, with a final differentiation frequency of 33.54% at the end of tenth day. Transgenic banana plants overexpressing MusaVND1 showed stunted growth and were characterized by PCR and Southern blot analysis. Transgenic banana plants showed transdifferentiation of various types of cells into xylem vessel elements and ectopic deposition of lignin in cells of various plant organs such as leaf and corm. Tracheary element formation was seen in the cortical region of transgenic corm as well as in epidermal cells of leaves. Biochemical analysis indicates significantly higher levels of lignin and cellulose content in transgenic banana lines than control plants. MusaVND1 overexpressing transgenic banana plants showed elevated expression levels of genes involved in lignin and cellulose biosynthesis pathway. Further expression of different MYB transcription factors positively regulating secondary wall deposition was also up regulated in MusaVND1 transgenic lines.

Psychosis-proneness correlates with expression levels of dopaminergic genes

Psychosis-proneness or schizotypy is a personality organisation mirroring individual risk for schizophrenia-development. Believed to be a fully dimensional construct sharing considerable geno- and phenotypal variance with clinical schizophrenia, it has become an increasingly promising tool for basic psychosis-research. Although many studies show genetic commonalities between schizotypy and schizophrenia, changes in regulation of gene expression have never been examined in schizotypy before. We therefore extracted RNA from the blood, a valid surrogate for brain tissue, of a large sample of 67 healthy male volunteers and correlated the activities of all genes relevant for dopaminergic neurotransmission with the positive schizotypy-scale of the O-LIFE. We found significant negative correlations regarding the expression of the genes COMT, MAOB, DRD4, DRD5 and FOS, indicating that increased schizotypy coincides with higher levels of dopaminergic dysregulation on the mRNA-level. Considering the advantages of this method, we suggest that it be applied more often in fundamental psychosis-research.

Asymmetrical expression of BDNF and NTRK3 genes in frontoparietal cortex of stress-resilient rats in an animal model of depression.

The current study is based on the "approach-withdrawal" theory of emotional regulation and lateralization of brain function in rodents, which has little been studied. The aim was to indentify asymmetry in hemispheric genes expression during depression. Depressive-like symptoms were induced in rats using chronic mild stress protocol. The sucrose consumption test was performed to identify the anhedonic and stress-resilient rats. After decapitation, RNA was extracted from frontotemporal cortex of both hemispheres of anhedonic and stress-resilient rats. The pattern of gene expression in these samples was compared with controls by real-time polymerase chain reaction. A linear mixed model analysis of variance was fitted to the data to estimate the effect of rat line. From the total of 30 rats in the experimental group, five rats were identified to be anhedonic and five were stress-resilient, according to the result of sucrose-consumption test. BDNF and NTRK-3 were expressed at significantly lower levels in the right hemisphere of anhedonic rats compared with stress-resilient rats. No significant difference was found between left hemispheres. Hemispheric asymmetry in the level of gene expression was only observed for the BDNF gene in stress-resilient rats, upregulated in right hemisphere compared with the left. Expression of NTRK3, HTR2A, COMT, and SERT was not lateralized. There was no significant asymmetry between hemispheres of anhedonic rats. This study supports the evidence for the role of genes responsible for neural plasticity in pathophysiology of depression, emphasizing probable hemispheric asymmetry at level of gene expression.

Abstract 3679: Modulation of estrogen depurinating DNA adduct by sulforaphane or KEAP1 knockdown in human breast epithelial cells.

Abstract Modulation of estrogen depurinating DNA adduct by sulforaphane or KEAP1 knockdown in human breast epithelial cells Sulforaphane (SFN) is a potent inducer of detoxication enzymes such as NAD(P)H:quinone oxidoreductase (NQO1) and glutathione-S-transferases (GST) via the Kelch-like ECH-associated protein 1 (Keap1) - Nuclear Factor- E2-related factor (Nrf2) signaling pathway. NQO1 reduces the carcinogenic estrogen metabolite, catechol estrogen-3,4-quinone (CE-3,4-Q), while GSTs detoxify it through nucleophilic addition. CE-3,4-Q can bind with DNA to form depurinating DNA adducts. Thus, SFN, a isothiocyanate found in broccoli, may alter estrogen metabolism to protect against estrogen-mediated carcinogenesis. MCF10A cells were treated with either vehicle or SFN (10 μM) and either estradiol (E2) or 4-OHE2 (10 μM). NQO1 activity increased 3.2-fold by SFN treatment compared to vehicle. Estrogen metabolites and depurinating DNA adducts in the cell culture medium were partially purified by solid phase extraction and then analyzed by UHPLC-MS/MS. Following E2 treatment, 4-OHE1/2-1-N3Ade and 4-OHE1/2-1-N7Gua adducts were reduced by 60% in SFN treatment; 4-OHE1/2- glutathione conjugates increased 1.9 while 4-OCH3E1/2 increased 3.0 fold with SFN. Following treatment with the proximate metabolite 4-OHE2, 4-OHE1/2-1-N3Ade and 4-OHE 1/2-1-N7Gua adducts also decreased 60% in SFN treated cells compared to vehicle; while 4-OHE1/2-glutathione-conjugates increased 5.0-fold and 4-OCH3E1/2 levels were 3.4-fold higher. To constitutively enhance the expression of Nrf2-regulated genes including NQO1, cells were treated with either scrambled or siKEAP1 RNA and E2 or 4-OHE2. NQO1 activity increased 2.2-fold with siKEAP1 treatment. Following E2 treatment, 4-OHE1/2-1-N3Ade and 4-OHE1/2-1-N7Gua adducts dropped 70% in siKEAP1 treated cells compared to scrambled; 4-OHE1/2-glutathione conjugates increased 1.3-fold; however, 4-OCH3E1/2 decreased 50% with siKEAP1 treatment. Following 4-OHE2 treatment, the 4-OHE1/2-1-N3Ade and 4-OHE 1/2-1-N7Gua adducts declined 60% in siKEAP1 treated cells compared to scrambled; 4-OHE1/2-glutathione conjugates increased 1.4-fold while 4-OCH3E1/2 declined 60% with siKEAP1 treatment. SFN or siKEAP1 have similar effects on up-regulating NQO1 transcripts, protein expression and activity levels and on diminution of depurinating estrogen DNA adducts following E2 or 4-OHE2 challenge. However, these pharmacologic and genetic approaches have different effects on COMT. siKEAP1 down-regulates COMT expression, which inhibits 4-OCH3E1 but not 4-CH3E2 formation whilst SFN elevates COMT expression and subsequently levels of 4-OCH3E1/2. Thus, activation of the Nrf2 pathway may account for some but not all of the protective effects of SFN against estrogen-mediated DNA damage. Supported by DOD BCRP Postdoctoral Fellowship103928. Citation Format: Li Yang, Muhammad Zahid, Eleanor G. Rogan, Ercole L. Cavalieri, James D, Yager, Kala Visvanathan, John Groopman, Nancy E. Davidson, Thomas W. Kensler. Modulation of estrogen depurinating DNA adduct by sulforaphane or KEAP1 knockdown in human breast epithelial cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3679. doi:10.1158/1538-7445.AM2013-3679

Opposite effects of tolcapone on amphetamine-disrupted startle gating in low vs. high COMT-expressing rat strains

BackgroundDifferential sensitivity to the prepulse inhibition (PPI)-disruptive effects of dopamine agonists in Sprague–Dawley (SD) vs. Long Evans (LE) rats is heritable, reflects differential activation of DA signaling, and is associated with differences in the brain expression of specific genes, including those of the catecholamine catabolic enzyme, catechol-O-methyltransferase (COMT). In humans, both basal and drug-modified PPI differs significantly between individuals with polymorphisms conferring low- vs. high-activity of COMT. We used the COMT inhibitor, tolcapone, to assess the role of COMT activity in regulating the differential effects of the dopamine releaser, amphetamine (AMPH), on PPI in SD and LE rats. MethodsAcoustic startle and PPI were assessed in SD and LE male rats after pretreatment with tolcapone (vehicle vs. 30mg/kg ip) and treatment with AMPH (vehicle vs. 4.5mg/kg sc), using 10–120ms prepulse intervals. ResultsAfter tolcapone, AMPH significantly potentiated PPI in LE rats, and significantly disrupted PPI in SD rats. These patterns could not be explained by drug effects on pulse alone startle magnitude. DiscussionThe impact of COMT inhibition on AMPH-modified PPI was categorically different in strains exhibiting low vs. high levels of forebrain Comt expression, consistent with reports in humans that tolcapone has opposite effects on PPI among individuals with polymorphisms conferring low vs. high COMT activity. The present model provides a basis for understanding the mechanisms by which the effects of COMT inhibition on sensorimotor gating – and potentially, related neurocognitive and clinical functions – under hyperdopaminergic states are dependent on an individual's basal levels of COMT activity.

Disturbed balance between phase I and II metabolizing enzymes in ovarian endometriosis: A source of excessive hydroxy-estrogens and ROS?

Oxidative metabolism of estrogens was studied in 31 ovarian endometriosis and 29 normal endometrium samples, by qPCR. Expression was monitored for genes encoding five estrogen hydroxylating, five hydroxy (OH)-estrogen conjugating, and three estrogen quinone detoxifying enzymes. CYP1B1, COMT, NQO1, and GSTP1 protein levels were determined using Western blotting and immunohistochemistry staining. Increased expression of CYP1A1, CYP3A7 and COMT, and higher levels of MB-COMT were seen in endometriosis, as compared to normal endometrium. Expression of CYP1B1, CYP3A5, SULT1A1 and NQO2 was unchanged, with comparable CYP1B1 protein levels. Expression of SULT1E1, SULT2B1, UGT2B7, NQO1, and GSTP1 was decreased. Three NQO1 isoforms were detected; NQO1c appears to be endometriosis-specific. Our data indicate a disturbed balance between phase I and II metabolizing enzymes in endometriosis, potentially leading to excessive OH-estrogen and altered ROS formation, and stimulation of proliferation of ectopic endometrium. This is the first report on disturbed expression of estrogen oxidative metabolism genes in ovarian endometriosis.

Selective overexpression of Comt in prefrontal cortex rescues schizophrenia-like phenotypes in a mouse model of 22q11 deletion syndrome

The 22q11.2 microdeletion is one of the highest genetic risk factors for schizophrenia. It is not well understood which interactions of deleted genes in 22q11.2 regions are responsible for the pathogenesis of schizophrenia, but catechol-O-methytransferase (COMT) is among the candidates. Df1/+ mice are 22q11.2 deletion syndrome (22q11DS) model mice with a hemizygous deletion of 18 genes in the 22q11-related region. Df1/+ mice showed enhanced response to the dopamine D1 agonist, SKF38393, and the N-methyl-D-aspartate antagonist, MK801, which can be normalized by a GABAA receptor agonist, bretazenil, or a GABAA α2/α3 receptor agonist, SL651498. Here, we demonstrated the curing effects of virus-mediated reintroduction of Comt to the prefrontal cortex (PFC) in Df1/+ mice. In contrast, both Comt overexpression and Comt inhibition caused an abnormal responsiveness to Bretazenil, a GABAA receptor agonist in control mice. Comt overexpression increased MK801-induced interneuronal activation and GABA release in the PFC. The expression levels of GABA-related genes such as Gabrb2 (GABAAreceptor β2), Gad2 (glutamic acid decarboxylase 65 (Gad65)) and Reln (Reelin) correlate with a Comt expression level in PFC. Our data suggest that Comt-mediated regulation of GABAergic system might be involved in the behavioral pathogenesis of Df1/+ mice.

Fronto-temporal-mesolimbic gene expression and heritable differences in amphetamine-disrupted sensorimotor gating in rats

Differences in sensitivity to the prepulse inhibition (PPI)-disruptive effects of D2-family agonists in Sprague-Dawley (SD) vs. Long Evans (LE) rats are heritable, reflect differential activation of DA signaling in the nucleus accumbens (NAC), and are associated with differences in expression of specific NAC genes. These differences may inform us about the biology of PPI deficits in disorders such as schizophrenia. After confirming these strain-based PPI differences, we measured expression of four genes in NAC and other regions that regulate PPI: medial prefrontal cortex and ventral hippocampus (VH). Startle and PPI were assessed in SD and LE rats administered D-amphetamine (0 vs. 4.5 mg/kg, sc). Two weeks later, brain tissue was processed for comt, nrg1, grid2, and csnk1e expression; blood comt expression was also tested. Data confirmed expected PPI phenotypes. Gene expression levels differed across strains, sexes, and brain regions, with LE > SD expression in most genes and regions, and female > male expression for all NAC genes. Within any brain region, expression of the four genes was highly inter-correlated; across regions, correlations were less robust, reflecting distinct strain- or sex-based subgroups. PPI amphetamine sensitivity at 120 ms correlated significantly with NAC nrg1 expression, while amphetamine sensitivity for 30 ms PPI and startle magnitude correlated significantly with VH nrg1 and blood comt expression. Rat strains differing in a schizophrenia-linked phenotype also differ in expression levels of genes associated both with that phenotype, and with schizophrenia, within brain regions associated with that phenotype and schizophrenia.

ERα phenotype, estrogen level, and benzo[a]pyrene exposure modulate tumor growth and metabolism of lung adenocarcinoma cells

Women have a higher risk of lung adenocarcinoma than men, suggesting that estrogen pathway may be involved in the pathogenesis of this cancer. This study was designed to determine whether ERα expression, estrogen levels, and endocrine disruptor exposure would influence tumor growth of lung adenocarcinoma cells using a xenograft model in which human lung adenocarcinoma cells with and without transgenic ERα expression were transplanted into female nude mice. Results showed that estrogen promoted tumor growth of ERα+ lung adenocarcinoma cells but inhibited that of ERα− lung adenocarcinoma cells. Endocrine disruptor benzo[a]pyrene stimulated ERα− tumor growth dose dependently. Either of ovariectomy and ERα expression abolished the tumor growth-promoting effect of benzo[a]pyrene. The high CYP1B1/CYP1A1 and low COMT/CYP1B1 expression ratios detected in ERα+ tumors suggested an accumulation of 4-hydroxyestradiol metabolite under high body estrogen, whereas comparable CYP1A1 and CYP1B1 expression plus estrogen-inducible COMT expression might favor the formation of 2-methoxyestradiol in ERα− tumors. Inhibition of estrogen on ERα− tumor growth might be partly attributable to the anti-proliferative action of 2-methoxyestradiol. Benzo[a]pyrene increased expression of CYP1B1 over CYP1A1 and suppressed estrogen-induced COMT up-regulation in ERα− tumor cells, probably switching estrogen metabolism to 4-hydroxyestradiol formation and removing the inhibition of 2-methoxyestradiol on ERα− tumors. ERα inhibited AhR from up-regulating CYP1 in response to benzo[a]pyrene exposure, but it increased angiogenic VEGF-A expression with body estrogen levels. Estrogen might increase ERα+ lung adenocarcinoma growth by up-regulating cancer-related ERα target gene expression.

Comparative genomics and evolutionary analyses of the O-methyltransferase gene family in Populus

S-adenosyl- l-methionine (SAM) dependent O-methyltransferases (OMTs) proteins are involved in the methylation of various secondary metabolites. The OMT genes have been studied in various plants, but these studies focused either on a single or a small set of genes. Moreover, no comprehensive study was published yet on the OMT gene family in a tree species. To investigate the evolutionary history of this gene family and the functional diversification of its members, phylogenetic and several comparative genomics analyses were performed. Phylogeny across land plant lineages showed that OMT genes were distributed in two main classes deeply rooted in the phylogeny of land plants, suggesting that they have evolved by a gene duplication that had happen in the ancestor of land plants. COMT and COMT-like genes were clustering with few flavonoid and multifunctional OMT genes in class II. Class I included flavonoid, simple phenol, and multifunctional OMT genes. All 26 Populus OMT genes were located in segmental duplication blocks and two third of them were tandem duplicated, indicating the role of duplication processes in the expansion of this gene family. Expression profiling of OMT genes in Populus showed that only PoptrOMT25 was differentially expressed in xylem. The other genes were differentially expressed in leaves, bark, or both. Some OMT genes showed differential expression patterns under various biotic and abiotic stresses. The divergence of protein sequences, the phylogenetic distribution, and the expression of COMT and COMT-like genes suggest that they have evolved different functions or tissue specificities following duplications.

Disturbed expression of phase I and phase II estrogen-metabolizing enzymes in endometrial cancer: Lower levels of CYP1B1 and increased expression of S-COMT

Expression levels of genes encoding phase I and phase II estrogen-metabolizing enzymes: CYP1A1, CYP1A2, CYP1B1, CYP3A5, CYP3A7, SULT1A1, SULT1E1, SULT2B1, COMT, UGT2B7, and GSTP1 were studied by real-time PCR in 38 samples of cancerous and adjacent control endometrium. We found significantly lower levels of CYP1B1 and CYP3A7, higher levels of SULT2B1, UGT2B7 and GSTP1, and no differences in expression of COMT, CYP1A1, CYP3A5, SULT1E1 and SULT2A1 in the endometrial cancers. The CYP1B1 and COMT proteins were also examined by Western blotting and immunohistochemical staining, supporting the real-time PCR analysis. Lower levels of CYP1B1 detected in cancerous endometrium suggest its important role in control, precancerous tissue. Additionally, we showed for the first time higher protein levels of soluble COMT in cancerous endometrium, and higher levels of membrane-bound COMT in control, precancerous endometrium. The importance of the changed ratio between soluble and membrane-bound COMT still needs to be evaluated in further studies.