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1.
Front Immunol ; 15: 1374437, 2024.
Article in English | MEDLINE | ID: mdl-38711507

ABSTRACT

Mycobacterium avium complex (MAC) is a non-tuberculous mycobacterium widely distributed in the environment. Even though MAC infection is increasing in older women and immunocompromised patients, to our knowledge there has been no comprehensive analysis of the MAC-infected host-cell transcriptome-and particularly of long non-coding RNAs (lncRNAs). By using in vitro-cultured primary mouse bone-marrow-derived macrophages (BMDMs) and Cap analysis of gene expression, we analyzed the transcriptional and kinetic landscape of macrophage genes, with a focus on lncRNAs, during MAC infection. MAC infection of macrophages induced the expression of immune/inflammatory response genes and other genes similar to those involved in M1 macrophage activation, consistent with previous reports, although Nos2 (M1 activation) and Arg1 (M2 activation) had distinct expression profiles. We identified 31 upregulated and 30 downregulated lncRNA promoters corresponding respectively to 18 and 26 lncRNAs. Upregulated lncRNAs were clustered into two groups-early and late upregulated-predicted to be associated with immune activation and the immune response to infection, respectively. Furthermore, an Ingenuity Pathway Analysis revealed canonical pathways and upstream transcription regulators associated with differentially expressed lncRNAs. Several differentially expressed lncRNAs reported elsewhere underwent expressional changes upon M1 or M2 preactivation and subsequent MAC infection. Finally, we showed that expressional change of lncRNAs in MAC-infected BMDMs was mediated by toll-like receptor 2, although there may be other mechanisms that sense MAC infection. We identified differentially expressed lncRNAs in MAC-infected BMDMs, revealing diverse features that imply the distinct roles of these lncRNAs in MAC infection and macrophage polarization.


Subject(s)
Gene Expression Profiling , Macrophages , Mycobacterium avium Complex , Mycobacterium avium-intracellulare Infection , RNA, Long Noncoding , Transcriptome , RNA, Long Noncoding/genetics , Animals , Macrophages/immunology , Macrophages/microbiology , Macrophages/metabolism , Mycobacterium avium Complex/immunology , Mycobacterium avium Complex/genetics , Mice , Mycobacterium avium-intracellulare Infection/immunology , Mycobacterium avium-intracellulare Infection/genetics , Mycobacterium avium-intracellulare Infection/microbiology , Macrophage Activation/genetics , Macrophage Activation/immunology , Mice, Inbred C57BL , Cells, Cultured , Gene Expression Regulation
2.
Commun Biol ; 5(1): 414, 2022 05 04.
Article in English | MEDLINE | ID: mdl-35508708

ABSTRACT

Hepatocytes are the dominant cell type in the human liver, with functions in metabolism, detoxification, and producing secreted proteins. Although gene regulation and master transcription factors involved in the hepatocyte differentiation have been extensively investigated, little is known about how the epigenome is regulated, particularly the dynamics of DNA methylation and the critical upstream factors. Here, by examining changes in the transcriptome and the methylome using an in vitro hepatocyte differentiation model, we show putative DNA methylation-regulating transcription factors, which are likely involved in DNA demethylation and maintenance of hypo-methylation in a differentiation stage-specific manner. Of these factors, we further reveal that GATA6 induces DNA demethylation together with chromatin activation in a binding-site-specific manner during endoderm differentiation. These results provide an insight into the spatiotemporal regulatory mechanisms exerted on the DNA methylation landscape by transcription factors and uncover an epigenetic role for transcription factors in early liver development.


Subject(s)
DNA Methylation , GATA6 Transcription Factor , Cell Differentiation/genetics , Chromatin Immunoprecipitation , GATA6 Transcription Factor/genetics , GATA6 Transcription Factor/metabolism , Hepatocytes/metabolism , Humans
3.
Chromosome Res ; 30(1): 109-121, 2022 03.
Article in English | MEDLINE | ID: mdl-35142952

ABSTRACT

DNA methylation of CpG dinucleotides is an important epigenetic modification involved in the regulation of mammalian gene expression, with each type of cell developing a specific methylation profile during its differentiation. Recently, it has been shown that a small subgroup of transcription factors (TFs) might promote DNA demethylation at their binding sites. We developed a bioinformatics pipeline to predict from genome-wide DNA methylation data TFs that promote DNA demethylation at their binding site. We applied the pipeline to International Human Epigenome Consortium methylome data and selected 393 candidate transcription factor binding motifs and associated 383 TFs that are likely associated with DNA demethylation. Validation of a subset of the candidate TFs using an in vitro assay suggested that 28 of 49 TFs from various TF families had DNA-demethylation-promoting activity; TF families, such as bHLH and ETS, contained both TFs with and without the activity. The identified TFs showed large demethylated/methylated CpG ratios and their demethylated CpGs showed significant bias toward hypermethylation in original cells. Furthermore, the identified TFs promoted demethylation of distinct sets of CpGs, with slight overlap of the targeted CpGs among TF family members, which was consistent with the results of a gene ontology (GO) term analysis of the identified TFs. Gene expression analysis of the identified TFs revealed that multiple TFs from various families are specifically expressed in human cells and tissues. Together, our results suggest that a large number of TFs from various TF families are associated with cell-type-specific DNA demethylation during human cellular development.


Subject(s)
DNA Demethylation , Transcription Factors , Animals , Binding Sites , DNA/metabolism , DNA Methylation , Genome , Humans , Mammals/genetics , Transcription Factors/genetics , Transcription Factors/metabolism
4.
Data Brief ; 33: 106482, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33241095

ABSTRACT

In vitro spermatogenesis, which produces fertile spermatozoa, has been successfully performed using an organ culture method from murine tissue. Here, we provide a dataset of time-course microarray transcriptome data of in vitro cultured neonate murine testes and age-matched in vivo-derived testes. The dataset presented here is related to the article titled "Transcriptome analysis reveals inadequate spermatogenesis and immediate radical immune reactions during organ culture in vitro spermatogenesis" published in Biochemical and Biophysical Research Communications in 2020 [1]. The raw data and pre-processed data are publicly available on the GEO repository (accession number GSE147982). Furthermore, the dataset provided here includes additional metadata, detailed explanations of the experiment, results of pre-processing, analysis scripts, and lists of differentially expressed genes from in vitro culture testes and in vivo testes at each time point.

5.
Biochem Biophys Res Commun ; 530(4): 732-738, 2020 10 01.
Article in English | MEDLINE | ID: mdl-32782148

ABSTRACT

Cultivation of neonatal mouse testis tissue can induce spermatogenesis and produce fertile sperms. However, in vitro spermatogenesis mediated by the current organ culture method comes short in fully mimicking the in vivo counterpart, partly due to a lack of knowledge underlying molecular phenotypes of in vitro spermatogenesis. In this study, we investigated transcriptome of cultured testis tissues using microarray method. Principle component analysis of the transcriptome data revealed delay and/or arrest of spermatogenesis and immediate radical immune reactions in the cultured testis tissues. The delay/arrest of spermatogenesis occurred before and during early meiotic phase, resulting in inefficient progression of meiosis. The immune reaction, on the other hand, was drastic and overwhelming, in which TLR4-NF-kB signaling was speculated to be involved. Notably, treatment with TAK242, an inhibitor of TLR4-NF-kB signaling pathway, ameliorated the macrophage activation which otherwise would exacerbate the inflammation. Thus, the present study revealed for the first time at molecular level that the deficiency of germ cell differentiation and the immense immune reaction are major abnormalities in the cultured testis tissues.


Subject(s)
Immunity, Innate , Organ Culture Techniques , Spermatogenesis , Testis , Transcriptome , Animals , Female , Gene Expression Profiling , Male , Meiosis , Mice, Inbred C57BL , Mice, Inbred ICR , Mice, Transgenic , NF-kappa B/genetics , NF-kappa B/immunology , Organ Culture Techniques/methods , Testis/cytology , Testis/immunology , Testis/metabolism , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/immunology
6.
Sci Rep ; 9(1): 6490, 2019 04 24.
Article in English | MEDLINE | ID: mdl-31019211

ABSTRACT

Mesenchymal-to-epithelial transition (MET) is an important step in cell reprogramming from fibroblasts (a cell type frequently used for this purpose) to various epithelial cell types. However, the mechanism underlying MET induction in fibroblasts remains to be understood. The present study aimed to identify the transcription factors (TFs) that efficiently induce MET in dermal fibroblasts. OVOL2 was identified as a potent inducer of key epithelial genes, and OVOL2 cooperatively enhanced MET induced by HNF1A, TP63, and KLF4, which are known reprogramming TFs to epithelial lineages. In TP63/KLF4-induced keratinocyte-like cell-state reprogramming, OVOL2 greatly facilitated the activation of epithelial and keratinocyte-specific genes. This was accompanied by enhanced changes in chromatin accessibility across the genome. Mechanistically, motif enrichment analysis revealed that the target loci of KLF4 and TP63 become accessible upon induction of TFs, whereas the OVOL2 target loci become inaccessible. This indicates that KLF4 and TP63 positively regulate keratinocyte-associated genes whereas OVOL2 suppresses fibroblast-associated genes. The exogenous expression of OVOL2 therefore disrupts fibroblast lineage identity and facilitates fibroblast cell reprogramming into epithelial lineages cooperatively with tissue-specific reprogramming factors. Identification of OVOL2 as an MET inducer and an epithelial reprogramming enhancer in fibroblasts provides new insights into cellular reprogramming improvement for future applications.


Subject(s)
Cellular Reprogramming/genetics , Epithelial Cells/metabolism , Epithelial-Mesenchymal Transition/genetics , Fibroblasts/metabolism , Gene Expression , Transcription Factors/genetics , Cell Lineage/genetics , Cell Transdifferentiation/genetics , Cells, Cultured , Chromatin/genetics , Chromatin/metabolism , Dermis/cytology , Epithelial Cells/cytology , Fibroblasts/cytology , Humans , Infant, Newborn , Kruppel-Like Factor 4 , Sequence Analysis, DNA/methods , Transcription Factors/metabolism
7.
Anal Sci ; 34(1): 1-4, 2018.
Article in English | MEDLINE | ID: mdl-29321448

ABSTRACT

In this study, we developed a new chlorine gas detection method using anodic oxidation and a photochemical reaction. Chlorine gas was temporarily solvated with an aprotic polar solvent having an extensive potential range in the positive direction, and the solvated chlorine molecule was detected by an anodic oxidation reaction. In addition, when combined with ultraviolet light irradiation, we could detect high sensitivity using the photochemical reaction.

8.
Epigenetics Chromatin ; 10(1): 60, 2017 12 08.
Article in English | MEDLINE | ID: mdl-29221486

ABSTRACT

BACKGROUND: DNA methylation is a fundamental epigenetic modification that is involved in many biological systems such as differentiation and disease. We and others recently showed that some transcription factors (TFs) are involved in the site-specific determination of DNA demethylation in a binding site-directed manner, although the reports of such TFs are limited. RESULTS: Here, we develop a screening system to identify TFs that induce binding site-directed DNA methylation changes. The system involves the ectopic expression of target TFs in model cells followed by DNA methylome analysis and overrepresentation analysis of the corresponding TF binding motif at differentially methylated regions. It successfully identified binding site-directed demethylation of SPI1, which is known to promote DNA demethylation in a binding site-directed manner. We extended our screening system to 15 master TFs involved in cellular differentiation and identified eight novel binding site-directed DNA demethylation-inducing TFs (RUNX3, GATA2, CEBPB, MAFB, NR4A2, MYOD1, CEBPA, and TBX5). Gene ontology and tissue enrichment analysis revealed that these TFs demethylate genomic regions associated with corresponding biological roles. We also describe the characteristics of binding site-directed DNA demethylation induced by these TFs, including the targeting of highly methylated CpGs, local DNA demethylation, and the overlap of demethylated regions between TFs of the same family. CONCLUSIONS: Our results show the usefulness of the developed screening system for the identification of TFs that induce DNA demethylation in a site-directed manner.


Subject(s)
Demethylation , Transcription Factors/metabolism , Binding Sites , DNA Methylation
10.
BMC Mol Biol ; 18(1): 9, 2017 04 04.
Article in English | MEDLINE | ID: mdl-28376714

ABSTRACT

BACKGROUND: SPI1 is an essential transcription factor (TF) for the hematopoietic lineage, in which its expression is tightly controlled through a -17-kb upstream regulatory region and a promoter region. Both regulatory regions are demethylated during hematopoietic development, although how the change of DNA methylation status is performed is still unknown. RESULTS: We found that the ectopic overexpression of RUNX1 (another key TF in hematopoiesis) in HEK-293T cells induces almost complete DNA demethylation at the -17-kb upstream regulatory region and partial but significant DNA demethylation at the proximal promoter region. This DNA demethylation occurred in mitomycin-C-treated nonproliferating cells at both regulatory regions, suggesting active DNA demethylation. Furthermore, ectopic RUNX1 expression induced significant endogenous SPI1 expression, although its expression level was much lower than that of natively SPI1-expressing monocyte cells. CONCLUSIONS: These results suggest the novel role of RUNX1 as an inducer of DNA demethylation at the SPI1 regulatory regions, although the mechanism of RUNX1-induced DNA demethylation remains to be explored.


Subject(s)
Core Binding Factor Alpha 2 Subunit/metabolism , DNA Methylation , DNA Replication , Proto-Oncogene Proteins/genetics , Trans-Activators/genetics , Base Sequence , Cell Line , Core Binding Factor Alpha 2 Subunit/genetics , Gene Expression Regulation , Humans , Promoter Regions, Genetic , Up-Regulation
11.
Surg Case Rep ; 3(1): 25, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28188513

ABSTRACT

BACKGROUND: Lung cancer rarely metastasizes to the breast, and breast metastasis of pulmonary pleomorphic carcinoma has not been previously reported. CASE PRESENTATION: The patient was a 66-year-old woman who became aware of a mass in the right breast and visited a physician. She was referred to our department for close examination, upon which she was diagnosed with double cancer (right breast cancer and left lung cancer). Needle biopsy findings for the mammary tumor were similar to those for the lung biopsy specimen, but spindle cell or metaplastic carcinoma were possibilities. The initial diagnosis was primary breast cancer. Left upper lobectomy and lymph node dissection were performed for left lung cancer. Both the lung and mammary tumors grew rapidly during the wait for surgery. The white blood cell count was within the normal range at the first examination, but was markedly increased and remained at a high level after surgery for lung cancer. Preoperative chemotherapy was initially planned for the mammary tumor, but surgical treatment was selected in consideration of the clinical course, and right mastectomy and full thickness skin graft were performed. However, the disease rapidly aggravated and the patient died 5 months after the first examination. CONCLUSION: The final diagnosis was pulmonary pleomorphic carcinoma with metastasis to the breast on postoperative histopathological examination. We describe this case as the first reported example of breast metastasis of pulmonary pleomorphic carcinoma.

12.
Blood Adv ; 1(20): 1699-1711, 2017 Sep 12.
Article in English | MEDLINE | ID: mdl-29296817

ABSTRACT

RUNX1 is an essential master transcription factor in hematopoietic development and plays important roles in immune functions. Although the gene regulatory mechanism of RUNX1 has been characterized extensively, the epigenetic role of RUNX1 remains unclear. Here, we demonstrate that RUNX1 contributes DNA demethylation in a binding site-directed manner in human hematopoietic cells. Overexpression analysis of RUNX1 showed the RUNX1-binding site-directed DNA demethylation. The RUNX1-mediated DNA demethylation was also observed in DNA replication-arrested cells, suggesting an involvement of active demethylation mechanism. Coimmunoprecipitation in hematopoietic cells showed physical interactions between RUNX1 and DNA demethylation machinery enzymes TET2, TET3, TDG, and GADD45. Further chromatin immunoprecipitation sequencing revealed colocalization of RUNX1 and TET2 in the same genomic regions, indicating recruitment of DNA demethylation machinery by RUNX1. Finally, methylome analysis revealed significant overrepresentation of RUNX1-binding sites at demethylated regions during hematopoietic development. Collectively, the present data provide evidence that RUNX1 contributes site specificity of DNA demethylation by recruitment of TET and other demethylation-related enzymes to its binding sites in hematopoietic cells.

13.
PLoS One ; 11(8): e0160459, 2016.
Article in English | MEDLINE | ID: mdl-27483142

ABSTRACT

Transcriptional regulatory network (TRN) reconstitution and deconstruction occur simultaneously during reprogramming; however, it remains unclear how the starting and targeting TRNs regulate the induction and suppression of peripheral genes. Here we analyzed the regulation using direct cell reprogramming from human dermal fibroblasts to monocytes as the platform. We simultaneously deconstructed fibroblastic TRN and reconstituted monocytic TRN; monocytic and fibroblastic gene expression were analyzed in comparison with that of fibroblastic TRN deconstruction only or monocytic TRN reconstitution only. Global gene expression analysis showed cross-regulation of TRNs. Detailed analysis revealed that knocking down fibroblastic TRN positively affected half of the upregulated monocytic genes, indicating that intrinsic fibroblastic TRN interfered with the expression of induced genes. In contrast, reconstitution of monocytic TRN showed neutral effects on the majority of fibroblastic gene downregulation. This study provides an explicit example that demonstrates how two networks together regulate gene expression during cell reprogramming processes and contributes to the elaborate exploration of TRNs.


Subject(s)
Cellular Reprogramming , Fibroblasts/metabolism , Gene Regulatory Networks , Monocytes/metabolism , Transcription, Genetic , Cell Line , Fibroblasts/cytology , Gene Expression Profiling , Gene Expression Regulation , Genetic Vectors/chemistry , Genetic Vectors/metabolism , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , LIM-Homeodomain Proteins/genetics , LIM-Homeodomain Proteins/metabolism , Lentivirus/genetics , Lentivirus/metabolism , Microarray Analysis , Monocytes/cytology , Repressor Proteins/genetics , Repressor Proteins/metabolism , Skin/cytology , Skin/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Transduction, Genetic , Twist-Related Protein 1/genetics , Twist-Related Protein 1/metabolism
14.
J Immunol ; 194(12): 6035-44, 2015 Jun 15.
Article in English | MEDLINE | ID: mdl-25957166

ABSTRACT

Basic leucine zipper transcription factor Batf2 is poorly described, whereas Batf and Batf3 have been shown to play essential roles in dendritic cell, T cell, and B cell development and regulation. Batf2 was drastically induced in IFN-γ-activated classical macrophages (M1) compared with unstimulated or IL-4-activated alternative macrophages (M2). Batf2 knockdown experiments from IFN-γ-activated macrophages and subsequent expression profiling demonstrated important roles for regulation of immune responses, inducing inflammatory and host-protective genes Tnf, Ccl5, and Nos2. Mycobacterium tuberculosis (Beijing strain HN878)-infected macrophages further induced Batf2 and augmented host-protective Batf2-dependent genes, particularly in M1, whose mechanism was suggested to be mediated through both TLR2 and TLR4 by LPS and heat-killed HN878 (HKTB) stimulation experiments. Irf1 binding motif was enriched in the promoters of Batf2-regulated genes. Coimmunoprecipitation study demonstrated Batf2 association with Irf1. Furthermore, Irf1 knockdown showed downregulation of IFN-γ- or LPS/HKTB-activated host-protective genes Tnf, Ccl5, Il12b, and Nos2. Conclusively, Batf2 is an activation marker gene for M1 involved in gene regulation of IFN-γ-activated classical macrophages, as well as LPS/HKTB-induced macrophage stimulation, possibly by Batf2/Irf1 gene induction. Taken together, these results underline the role of Batf2/Irf1 in inducing inflammatory responses in M. tuberculosis infection.


Subject(s)
Basic-Leucine Zipper Transcription Factors/genetics , Interferon Regulatory Factor-1/genetics , Macrophages/immunology , Macrophages/metabolism , Mycobacterium Infections/genetics , Mycobacterium Infections/immunology , Mycobacterium/immunology , Animals , Basic-Leucine Zipper Transcription Factors/metabolism , Cluster Analysis , Disease Models, Animal , Gene Expression , Gene Expression Profiling , Gene Expression Regulation/drug effects , Gene Knockdown Techniques , Interferon Regulatory Factor-1/metabolism , Interferon-gamma/pharmacology , Lipopolysaccharides/immunology , Macrophage Activation/immunology , Male , Mice , Mycobacterium Infections/metabolism , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/metabolism , Protein Binding , Tumor Necrosis Factors/genetics , Tumor Necrosis Factors/metabolism
15.
Toxicology ; 326: 18-24, 2014 Dec 04.
Article in English | MEDLINE | ID: mdl-25291031

ABSTRACT

We recently reported that Δ(9)-tetrahydrocannabinol (Δ(9)-THC), a major cannabinoid component in Cannabis Sativa (marijuana), significantly stimulated the expression of fatty acid 2-hydroxylase (FA2H) in human breast cancer MDA-MB-231 cells. Peroxisome proliferator-activated receptor α (PPARα) was previously implicated in this induction. However, the mechanisms mediating this induction have not been elucidated in detail. We performed a DNA microarray analysis of Δ(9)-THC-treated samples and showed the selective up-regulation of the PPARα isoform coupled with the induction of FA2H over the other isoforms (ß and γ). Δ(9)-THC itself had no binding/activation potential to/on PPARα, and palmitic acid (PA), a PPARα ligand, exhibited no stimulatory effects on FA2H in MDA-MB-231 cells; thus, we hypothesized that the levels of PPARα induced were involved in the Δ(9)-THC-mediated increase in FA2H. In support of this hypothesis, we herein demonstrated that; (i) Δ(9)-THC activated the basal transcriptional activity of PPARα in a concentration-dependent manner, (ii) the concomitant up-regulation of PPARα/FA2H was caused by Δ(9)-THC, (iii) PA could activate PPARα after the PPARα expression plasmid was introduced, and (iv) the Δ(9)-THC-induced up-regulation of FA2H was further stimulated by the co-treatment with L-663,536 (a known PPARα inducer). Taken together, these results support the concept that the induced levels of PPARα may be involved in the Δ(9)-THC up-regulation of FA2H in MDA-MB-231 cells.


Subject(s)
Breast Neoplasms/enzymology , Dronabinol/pharmacology , Mixed Function Oxygenases/biosynthesis , PPAR alpha/drug effects , Signal Transduction/drug effects , Breast Neoplasms/genetics , Cell Line, Tumor , Cytochrome P-450 CYP1A1/biosynthesis , Cytochrome P-450 CYP1A1/genetics , Dose-Response Relationship, Drug , Enzyme Induction , Female , Gene Expression Regulation, Neoplastic , Humans , Indoles/pharmacology , Mixed Function Oxygenases/genetics , PPAR alpha/genetics , PPAR alpha/metabolism , Time Factors , Transcription, Genetic , Transfection , Up-Regulation
16.
J Toxicol Sci ; 38(4): 547-57, 2013.
Article in English | MEDLINE | ID: mdl-23824011

ABSTRACT

We reported that (-)-xanthatin, a xanthanolide sesquiterpene lactone present in the Cocklebur plant, exhibited potent anti-proliferative effects on human breast cancer cells, in which GADD45γ, a novel tumor suppressor gene, was induced. Mechanistically, topoisomerase IIα (Topo IIα) inhibition by (-)-xanthatin was shown to be the upstream trigger that stimulated the expression of GADD45γ mRNA and concomitantly produced reactive oxygen species (ROS) to maintain this expression. Since the anti-cancer drug etoposide, a selective Topo IIα inhibitor, has also been shown to induce intracellular ROS, (-)-xanthatin may exert its anti-proliferative effects on cancer cells in a similar manner to those of etoposide. In the present study, to generalize its applicability to cancer therapy, we further investigated the biological activities of (-)-xanthatin by comparing its activities to those of the established anti-cancer drug etoposide. After the exposure of breast cancer cells to (-)-xanthatin or etoposide, a prolonged and marked up-regulation in the expression of c-fos, a proapoptotic molecule, was detected together with GADD45γ; and the expression of these molecules was stabilized by ROS and abrogated by the pretreatment with N-acetyl-L-cysteine (NAC), a potent ROS scavenger. (-)-Xanthatin in particular exhibited stronger anti-proliferative potential than that of etoposide, which underlies the marked induction of c-fos/GADD45γ and ROS production.


Subject(s)
Acetylcysteine/pharmacology , Antineoplastic Agents/pharmacology , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Cell Division/genetics , Free Radical Scavengers/pharmacology , Furans/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Genes, Tumor Suppressor/drug effects , Intracellular Signaling Peptides and Proteins/metabolism , Proto-Oncogene Proteins c-fos/metabolism , Antigens, Neoplasm , Breast Neoplasms/metabolism , DNA Topoisomerases, Type II , DNA-Binding Proteins/antagonists & inhibitors , Etoposide/pharmacology , Female , Humans , Reactive Oxygen Species/metabolism , Reverse Transcriptase Polymerase Chain Reaction/methods , Tumor Cells, Cultured , Up-Regulation , GADD45 Proteins
17.
Chem Res Toxicol ; 26(7): 1073-9, 2013 Jul 15.
Article in English | MEDLINE | ID: mdl-23718638

ABSTRACT

Δ(9)-Tetrahydrocannabinol (Δ(9)-THC) has been reported as possessing antiestrogenic activity, although the mechanisms underlying these effects are poorly delineated. In this study, we used the estrogen receptor α (ERα)-positive human breast cancer cell line, MCF-7, as an experimental model and showed that Δ(9)-THC exposures markedly suppresses 17ß-estradiol (E2)- induced MCF-7 cell proliferation. We demonstrate that these effects result from Δ(9)-THC's ability to inhibit E2-liganded ERα activation. Mechanistically, the data obtained from biochemical analyses revealed that (i) Δ(9)-THC up-regulates ERß, a repressor of ERα, inhibiting the expression of E2/ERα-regulated genes that promote cell growth and that (ii) Δ(9)-THC induction of ERß modulates E2/ERα signaling in the absence of direct interaction with the E2 ligand binding site. Therefore, the data presented support the concept that Δ(9)-THC's antiestrogenic activities are mediated by the ERß disruption of E2/ERα signaling.


Subject(s)
Dronabinol/pharmacology , Estrogen Receptor beta/metabolism , Estrogens/pharmacology , Signal Transduction/drug effects , Up-Regulation/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Dronabinol/chemistry , Estrogen Receptor alpha/antagonists & inhibitors , Estrogen Receptor alpha/metabolism , Estrogen Receptor beta/biosynthesis , Humans , Ligands , MCF-7 Cells , Structure-Activity Relationship , Tumor Cells, Cultured
18.
J Toxicol Sci ; 38(2): 305-8, 2013.
Article in English | MEDLINE | ID: mdl-23535410

ABSTRACT

To investigate gene(s) being regulated by ∆(9)-tetrahydrocannabinol (∆(9)-THC), we performed DNA microarray analysis of human breast cancer MDA-MB-231 cells, which are poorly differentiated breast cancer cells, treated with ∆(9)-THC for 48 hr at an IC50 concentration of approximately 25 µM. Among the highly up-regulated genes (> 10-fold) observed, fatty acid 2-hydroxylase (FA2H) was significantly induced (17.8-fold). Although the physiological role of FA2H has not yet been fully understood, FA2H has been shown to modulate cell differentiation. The results of Oil Red O staining after ∆(9)-THC exposure showed the distribution of lipid droplets (a sign of the differentiated phenotype) in cells. Taken together, the results obtained here indicate that FA2H is a novel ∆(9)-THC-regulated gene, and that ∆(9)-THC induces differentiation signal(s) in poorly differentiated MDA-MB-231 cells.


Subject(s)
Breast Neoplasms/genetics , Dronabinol/pharmacology , Mixed Function Oxygenases/genetics , RNA, Messenger/metabolism , Transcriptional Activation/drug effects , Breast Neoplasms/pathology , Cell Differentiation/drug effects , Female , Humans , Mixed Function Oxygenases/physiology , Oligonucleotide Array Sequence Analysis , PPAR alpha/physiology , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured , Up-Regulation
19.
Toxicology ; 305: 1-9, 2013 Mar 08.
Article in English | MEDLINE | ID: mdl-23313378

ABSTRACT

Previously, we reported that (-)-xanthatin, a naturally occurring xanthanolide present in the Cocklebur plant, exhibits potent anti-proliferative effects on human breast cancer cells, accompanied by an induction of the growth arrest and DNA damage-inducible gene 45γ (GADD45γ), recognized recently as a novel tumor suppressor gene. However, the mechanisms mediating this activation were unknown. Topoisomerase IIα (Topo IIα) inhibition has been reported to produce a cell death response accompanied by an atypical DNA laddering fragmentation profile, similar to that noted previously for (-)-xanthatin. Therefore we hypothesized that (-)-xanthatin's GADD45γ activation was mediated through the Topo IIα pathway. Here, we identify that (-)-xanthatin does function as a catalytic inhibitor of Topo IIα, promoting DNA damage. In addition, reactive oxygen species (ROS) were elevated in cells treated with this agent. Mechanistically, it was determined that the induced levels of GADD45γ mRNA resulting from (-)-xanthatin exposures were stabilized by coordinately produced ROS, and that the consequent induction of GADD45γ mRNA, GADD45γ protein and ROS generation were abrogated by co-treatment with N-acetyl-l-cysteine. Taken together, the data support the concept that Topo IIα inhibition by (-)-xanthatin is a trigger that stimulates expression of DNA damage-inducible GADD45γ mRNA and that concomitantly produced ROS act downstream to further enhance the GADD45γ mRNA/GADD45γ protein induction process, resulting in breast cancer cell death.


Subject(s)
Antigens, Neoplasm/physiology , DNA Topoisomerases, Type II/physiology , DNA-Binding Proteins/physiology , Furans/pharmacology , Insecticides/pharmacology , Intracellular Signaling Peptides and Proteins/biosynthesis , Reactive Oxygen Species/metabolism , Topoisomerase II Inhibitors , Acetylcysteine/pharmacology , Antigens, Neoplasm/drug effects , Blotting, Western , Cell Line, Tumor , DNA Damage , DNA Topoisomerases, Type II/drug effects , DNA, Neoplasm/drug effects , DNA-Binding Proteins/drug effects , Female , Free Radical Scavengers/pharmacology , Glutathione/metabolism , Half-Life , Humans , Intracellular Signaling Peptides and Proteins/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Up-Regulation/drug effects , GADD45 Proteins
20.
Biol Bull ; 217(3): 215-21, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20040746

ABSTRACT

We have re-observed in detail the development of the sea urchin species Temnopleurus toreumaticus, which is considered to be a typical indirect-developing species with a feeding larval stage. In this re-observation, we discovered two new morphological traits in the early embryonic stages of T. toreumaticus. The first trait is that, immediately after fertilization, the egg enters a stage in which wrinkles form on its surface as a result of actin polymerization. The second new trait is that the blastulae form wrinkles; in sea urchins, this has previously been known only in direct-developing species that have a nonfeeding larval stage and form wrinkles during the blastula stage, before hatching. These phenomena indicate that after fertilization, the egg of T. toreumaticus undergoes a surface transformation that is unprecedented in echinoderms, and that an indirect-developing sea urchin can form a wrinkled blastula.


Subject(s)
Blastula/cytology , Sea Urchins/cytology , Sea Urchins/growth & development , Zygote/cytology , Actins/metabolism , Animals , Microscopy , Microscopy, Fluorescence
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