RESUMEN
Acyl-CoA synthetase 4 (ACSL4) overexpression plays a causal role in the aggressiveness of triple negative breast cancer. In turn, a negative correlation has been established between ACSL4 and estrogen receptor alpha (ERα) expression. However, the upstream regulatory mechanisms leading to differential ACSL4 expression between triple negative breast cancer and ERα-positive cells remained unknown. We performed the characterization of the human ACSL4 promoter and the identification of transcription factors involved. Deletional analysis demonstrated the proximal 43 base pairs of the promoter are involved in overexpression. By site directed mutagenesis we describe that retinoid-related orphan receptor alpha (RORα), Sp1 and E2F elements are involved in the promoter activity. We established for the first time that estrogen-related receptor alpha (ERRα) is a transcription factor involved in the higher activation of the human ACSL4 promoter in breast cancer cells. Furthermore, a combination of inhibitors of ACSL4 and ERRα produced a synergistic decrease in MDA-MB-231 cell proliferation. We also demonstrated that ERα restoration in triple negative breast cancer cells downregulates ACSL4 expression. The results presented in this manuscript demonstrated transcriptional mechanism is involved in the different expression of ACSL4 in human breast cancer cell lines of different aggressiveness.
Asunto(s)
Coenzima A Ligasas/genética , Regiones Promotoras Genéticas , Neoplasias de la Mama Triple Negativas/genética , Regulación hacia Arriba , Línea Celular Tumoral , Coenzima A Ligasas/metabolismo , Factores de Transcripción E2F/metabolismo , Receptor alfa de Estrógeno/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Células MCF-7 , Mutagénesis Sitio-Dirigida , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Factor de Transcripción Sp1/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismoRESUMEN
Asthma and allergy affect hundreds of millions of people from childhood to old age. In most of them, the inflammatory process of respiratory allergies involves the participation of type 2 cytokines, derived from T helper-2 (Th2)-cell, and Group 2 Innate Lymphoid (ILC2) Cells. An efficient memory Th2 cell response is dependent on IL-13 produced by ILC2s, causing allergic lung inflammation and elevated serum levels of immunoglobulin E. ILC2 cells are derived from common lymphoid progenitors and their growing depends on the transcription factor RORA. The aim of this work was to identify genetic variants in RORA associated with asthma phenotypes and allergy markers. Genomic DNA samples of 1246 individuals participating from Social Changes Asthma and Allergy in Latin America Program (SCAALA) have been genotyped using Illumina Human 2.5 Omni Beadchip. Logistics regressions have been performed to analyze the association among RORA variants and asthma, skin prick tests (SPT), specific IgE and type 2 cytokine production. Twelve single nucleotide variants (SNVs) were significantly associated with atopy (Pâ¯<â¯0.01), in which four of them, rs10162630, rs17191519, rs17270243, and rs55796775 and their haplotypes were strongly and positively associated (Pâ¯<â¯0.001). Furthermore, these variants increased the RORA gene expression in silico analysis. Other SNVs in RORA were associated with allergy markers, atopic and non-atopic asthma. Therefore, it is believed that variants in RORA gene may influence immunologic features of asthma and allergies and could be possible targets for future treatment of allergic diseases.
Asunto(s)
Asma/genética , Predisposición Genética a la Enfermedad/genética , Hipersensibilidad/genética , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Polimorfismo de Nucleótido Simple/genética , Biomarcadores/metabolismo , Niño , Preescolar , Estudios de Cohortes , Citocinas/genética , Femenino , Genotipo , Humanos , Inmunidad Innata/genética , Inmunoglobulina E/sangre , Inmunoglobulina E/genética , Inflamación/genética , Interleucina-13/genética , Pulmón/metabolismo , Masculino , Células Th2/metabolismoRESUMEN
It is widely known that there is an increase in the inflammatory responses and oxidative stress in temporal lobe epilepsy (TLE). Further, the seizures follow a circadian rhythmicity. Retinoic acid receptor-related orphan receptor alpha (RORα) is related to anti-inflammatory and antioxidant enzyme expression and is part of the machinery of the biological clock and circadian rhythms. However, the participation of RORα in this neurological disorder has not been studied. The aim of this study was to evaluate the RORα mRNA and protein content profiles in the hippocampus of rats submitted to a pilocarpine-induced epilepsy model at different time points throughout the 24-h light-dark cycle analyzing the influence of the circadian rhythm in the expression pattern during the acute, silent, and chronic phases of the experimental model. Real-time PCR and immunohistochemistry results showed that RORα mRNA and protein expressions were globally reduced in both acute and silent phases of the pilocarpine model. However, 60days after the pilocarpine-induced status epilepticus (chronic phase), the mRNA expression was similar to the control except for the time point 3h after the lights were turned off, and no differences were found in immunohistochemistry. Our results indicate that the status epilepticus induced by pilocarpine is able to change the expression and daily variation of RORα in the rat hippocampal area during the acute and silent phases. These findings enhance our understanding of the circadian pattern present in seizures as well as facilitate strategies for the treatment of seizures.
Asunto(s)
Epilepsia/inducido químicamente , Epilepsia/metabolismo , Hipocampo/metabolismo , Agonistas Muscarínicos , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/biosíntesis , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Pilocarpina , Animales , Enfermedad Crónica , Ritmo Circadiano/genética , Regulación de la Expresión Génica/efectos de los fármacos , Hipocampo/efectos de los fármacos , Masculino , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Ratas , Ratas Wistar , Estado Epiléptico/inducido químicamente , Estado Epiléptico/genéticaRESUMEN
The expression of retinoid-acid-related orphan receptor α (RORα) was evaluated at the mRNA level using real-time polymerase chain reaction (qRT-PCR), and its expression localization was determined by in situ hybridization of adult Inner Mongolian cashmere goats at different times of the year. In situ hybridization demonstrated that RORαwas expressed in secondary hair follicles of the hair shaft, inner root sheath, outer root sheath, medulla, and other parts that are target organs of the RORαreceptor gene. qRT-PCR results showed that there was no significant difference in the RORa mRNA abundance in February, April, August, and October (P > 0.05), and the only difference occurred in December relative to February, August, and October (P < 0.05). This difference revealed that melatonin possibly promotes cashmere growth through the nuclear receptor RORα. This study provides a good foundation for future studies on the relationship between the melatonin receptor and cashmere growth; in addition, it provides new insights for increased cashmere production and quality.
Asunto(s)
Cabras/genética , Folículo Piloso/metabolismo , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Animales , Secuencia de Bases , Bovinos , ADN Complementario/genética , Regulación de la Expresión Génica , Hibridación in Situ , Masculino , Datos de Secuencia Molecular , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Alineación de SecuenciaRESUMEN
Dyslipidemia and obesity are especially prevalent in populations with Amerindian backgrounds, such as Mexican-Americans, which predispose these populations to cardiovascular disease. Here we design an approach, known as the cross-population allele screen (CPAS), which we conduct prior to a genome-wide association study (GWAS) in 19,273 Europeans and Mexicans, in order to identify Amerindian risk genes in Mexicans. Utilizing CPAS to restrict the GWAS input variants to only those differing in frequency between the two populations, we identify novel Amerindian lipid genes, receptor-related orphan receptor alpha (RORA) and salt-inducible kinase 3 (SIK3), and three loci previously unassociated with dyslipidemia or obesity. We also detect lipoprotein lipase (LPL) and apolipoprotein A5 (APOA5) harbouring specific Amerindian signatures of risk variants and haplotypes. Notably, we observe that SIK3 and one novel lipid locus underwent positive selection in Mexicans. Furthermore, after a high-fat meal, the SIK3 risk variant carriers display high triglyceride levels. These findings suggest that Amerindian-specific genetic architecture leads to a higher incidence of dyslipidemia and obesity in modern Mexicans.
Asunto(s)
Hipercolesterolemia/genética , Hipertrigliceridemia/genética , Indígenas Norteamericanos/genética , Obesidad/genética , Adulto , Apolipoproteína A-V , Apolipoproteínas A/genética , Estudios de Casos y Controles , Cromosomas Humanos Par 11/genética , Cromosomas Humanos Par 8/genética , Dislipidemias/genética , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Genotipo , Haplotipos , Humanos , Lipoproteína Lipasa/genética , Modelos Logísticos , Masculino , México/etnología , Persona de Mediana Edad , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Polimorfismo de Nucleótido Simple , Proteínas Quinasas/genética , Población Blanca/genética , Adulto JovenRESUMEN
The circadian expression of clock and clock-controlled cognition-related genes in the hippocampus would be essential to achieve an optimal daily cognitive performance. There is some evidence that retinoid nuclear receptors (RARs and RXRs) can regulate circadian gene expression in different tissues. In this study, Holtzman male rats from control and vitamin A-deficient groups were sacrificed throughout a 24-h period and hippocampus samples were isolated every 4 or 5 h. RARα and RXRß expression level was quantified and daily expression patterns of clock BMAL1, PER1, RORα, and REVERB genes, RORα and REVERB proteins, as well as temporal expression of cognition-related RC3 and BDNF genes were determined in the hippocampus of the two groups of rats. Our results show significant daily variations of BMAL1, PER1, RORα, and REVERB genes, RORα and REVERB proteins and, consequently, daily oscillating expression of RC3 and BDNF genes in the rat hippocampus. Vitamin A deficiency reduced RXRß mRNA level as well as the amplitude of PER1, REVERB gene, and REVERB protein rhythms, and phase-shifted the daily peaks of BMAL1 and RORα mRNA, RORα protein, and RC3 and BDNF mRNA levels. Thus, nutritional factors, such as vitamin A and its derivatives the retinoids, might modulate daily patterns of BDNF and RC3 expression in the hippocampus, and they could be essential to maintain an optimal daily performance at molecular level in this learning-and-memory-related brain area.