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1.
Yakugaku Zasshi ; 140(10): 1199-1206, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32999198

RESUMO

Potential risks to the fetus or infant should be considered prior to medication during pregnancy and lactation. It is essential to evaluate the exposure levels of drugs and their related factors in addition to toxicological effects. Epilepsy is one of the most common neurological complications in pregnancy; some women continue to use antiepileptic drugs (AEDs) to control seizures. Benzodiazepines (BZDs) are widely prescribed for several women who experience symptoms such as anxiety and insomnia during the postpartum period. In this review, we describe the 1) transport mechanisms of AEDs across the placenta and the effects of these drugs on placental transporters, and 2) the transfer of BZDs into breast milk. Our findings indicated that carrier systems were involved in the uptake of gabapentin (GBP) and lamotrigine (LTG) in placental trophoblast cell lines. SLC7A5 was the main contributor to GBP transport in placental cells. LTG was transported by a carrier that was sensitive to chloroquine, imipramine, quinidine, and verapamil. Short-term exposure to 16 AEDs had no effect on folic acid uptake in placental cells. However, long-term exposure to valproic acid (VPA) affected the expression of folate carriers (FOLR1, SLC46A1). Furthermore, VPA administration changed the expression levels of various transporters in rat placenta, suggesting that sensitivity to VPA differed across gestational stages. Lastly, we developed a method for quantifying eight BZDs in human breast milk and plasma using LC/MS/MS, and successfully applied it to quantify alprazolam in breast milk and plasma donated by a lactating woman.


Assuntos
Anticonvulsivantes/metabolismo , Benzodiazepinas/metabolismo , Transporte Biológico/genética , Aleitamento Materno , Gabapentina/metabolismo , Lactação/metabolismo , Lamotrigina/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/fisiologia , Troca Materno-Fetal , Leite Humano/metabolismo , Placenta/metabolismo , Ácido Valproico/metabolismo , Anticonvulsivantes/efeitos adversos , Benzodiazepinas/efeitos adversos , Benzodiazepinas/uso terapêutico , Linhagem Celular , Epilepsia/tratamento farmacológico , Feminino , Receptor 1 de Folato/genética , Receptor 1 de Folato/metabolismo , Gabapentina/efeitos adversos , Expressão Gênica/efeitos dos fármacos , Humanos , Lamotrigina/efeitos adversos , Gravidez , Complicações na Gravidez/tratamento farmacológico , Transportador de Folato Acoplado a Próton/genética , Transportador de Folato Acoplado a Próton/metabolismo , Ácido Valproico/efeitos adversos
2.
Cancer Sci ; 111(5): 1794-1804, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32154964

RESUMO

Folate receptor alpha (FRα) is overexpressed in >80% of epithelial ovarian cancer (EOC). Accordingly, folate is attracting attention as a targeting ligand for EOC. For EOC patients, paclitaxel (PTX) is generally used as a first-line chemotherapeutic agent in combination with platinum-based drugs. Cyclodextrin (CyD) is a potential new formulation vehicle for PTX that could replace Cremophor-EL, a traditional formulation vehicle that causes significant side effects, including neutropenia. Several years ago, folate-appended ß-CyD (Fol-c1 -ß-CyD) was developed as an FRα-targeting drug carrier, but its efficacy as a treatment for EOC remains to be determined. In this study, we assessed the antitumor activity of PTX in Fol-c1 -ß-CyD (PTX/Fol-c1 -ß-CyD) in EOC-derived cell lines. We found that PTX/Fol-c1 -ß-CyD killed not only FRα-expressing cells but also FRα-negative cells. In the FRα-negative A2780 cells, knockdown of proton-coupled folate transporter (PCFT) significantly decreased the cytotoxicity of PTX/Fol-c1 -ß-CyD, whereas knockdown of FRα did not. By contrast, knockdown of either FRα or proton-coupled folate transporter (PCFT) decreased the cytotoxicity of PTX/Fol-c1 -ß-CyD in FRα-expressing SK-OV-3 cells. Furthermore, the cytotoxicity of PTX/Fol-c1 -ß-CyD in A2780 cells was increased at acidic pH, and this increase was suppressed by PCFT inhibitor. In mice intraperitoneally inoculated with FRα-expressing or PCFT-expressing EOC cells, intraperitoneal administration of PTX/Fol-c1 -ß-CyD significantly suppressed the growth of both types of EOC cells relative to PTX alone, without inducing a significant change in the neutrophil/white blood cell ratio. Our data suggest that Fol-c1 -ß-CyD targets not only FRα but also PCFT, and can efficiently deliver anticancer drugs to EOC cells in the peritoneal cavity.


Assuntos
Carcinoma Epitelial do Ovário/metabolismo , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Ácido Fólico/química , Neoplasias Ovarianas/metabolismo , Transportador de Folato Acoplado a Próton/metabolismo , beta-Ciclodextrinas/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/administração & dosagem , Feminino , Receptor 1 de Folato/genética , Receptor 1 de Folato/metabolismo , Ácido Fólico/administração & dosagem , Expressão Gênica , Humanos , Camundongos , Estrutura Molecular , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Paclitaxel/administração & dosagem , Paclitaxel/química , Paclitaxel/farmacologia , Transportador de Folato Acoplado a Próton/genética , Ensaios Antitumorais Modelo de Xenoenxerto , beta-Ciclodextrinas/administração & dosagem
3.
Biofactors ; 46(1): 136-145, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31621972

RESUMO

The present study was aimed to explore the functional role of microRNA (miR)-29b in colon cancer, as well as underlying mechanisms. Expressions of miR-29b and folate receptor 1 (FOLR1) were measured in both human colon tumor samples and cell lines. Colon cancer cell lines SW480 and SW620 were transfected with miR-29b mimic, antisense oligonucleotides (ASO)-miR-29b, small interfering (siRNA) against FOLR1 (si-FOLR1), or corresponding negative controls (NCs), and then were incubated with or without oxaliplatin (L-OHP). Thereafter, cell viability, cytotoxicity, cell apoptosis, and expression of FOLR1, ATP Binding Cassette Subfamily G Member 2 (ABCG2) and p-glycoprotein (p-gp) were analyzed. We found that miR-29b was significantly decreased, while FOLR1 was statistically elevated in colon cancer samples and cell lines compared to the nontumor samples and nontumourigenic immortalized human colon epithelial cell line FHC. Overexpression of miR-29b markedly inhibited cell viability, promoted sensitivity to L-OHP, stimulated cell apoptosis (all p < .05), and decreased the levels of ABCG2 and p-gp in cancer cells, whereas suppression of miR-29b showed contrary results. Moreover, we observed that FOLR1 was a direct target of miR-29b and was negatively regulated by miR-29b. In addition, the findings revealed that the effects of FOLR1 inhibition on cell viability, sensitivity to L-OHP, cell apoptosis, and the levels of ABCG2 and p-gp were similar to overexpression of miR-29b. Taken together, our study suggests that miR-29b inhibits cell growth and promotes sensitivity to L-OHP in colon cancer by targeting FOLR1.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Receptor 1 de Folato/genética , MicroRNAs/metabolismo , Oxaliplatina/uso terapêutico , Idoso , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Neoplasias do Colo/genética , Feminino , Receptor 1 de Folato/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade
4.
ACS Appl Mater Interfaces ; 11(50): 46548-46557, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31763810

RESUMO

Actively targeted nanomedicines have promised to revolutionize cancer treatment; however, their clinical translation has been limited by either low targetability, use of unsafe materials, or tedious fabrication. Here, we developed CD44 and folate receptor (FR) dually targeted nanoparticulate doxorubicin (HA/FA-NP-DOX) based on a direct conjugate of two purely natural ligands, hyaluronic acid and folic acid (FA), for safe, highly specific, and potent treatment of ovarian tumors in vivo. HA/FA-NP-DOX had a small size and high DOX loading, wherein the particle size decreased from 115, 93, to 89 nm with increasing degree of substitution of FA from 6.4, 8.5, to 11.1, while increased from 80, 93, to 103 nm with increasing DOX loading from 15.0, 23.1, to 31.4 wt %. Interestingly, HA/FA-NP-DOX exhibited excellent lyophilization redispersibility and long-term storage stability with negligible drug leakage while it released 91% of DOX in 48 h at pH 5.0. Cellular studies corroborated that HA/FA-NP-DOX possessed high selectivity to both CD44 and FR, resulting in strong killing of CD44- and FR-positive SKOV-3 ovarian cancer cells while low toxicity against CD44- and FR-negative L929 fibroblast cells. In vivo studies revealed a long elimination half-life of 5.6 h, an elevated tumor accumulation of 12.0% ID/g, and an effective inhibition of the SKOV-3 ovarian tumor for HA/FA-NP-DOX, leading to significant survival benefits over free DOX·HCl and phosphate-buffered saline controls. These dually targeted nanomedicines are simple and safe, providing a potentially translatable treatment for CD44- and FR-positive malignancies.


Assuntos
Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Neoplasias Ovarianas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Doxorrubicina/química , Feminino , Receptor 1 de Folato/antagonistas & inibidores , Receptor 1 de Folato/genética , Humanos , Receptores de Hialuronatos/antagonistas & inibidores , Receptores de Hialuronatos/genética , Ligantes , Camundongos , Nanomedicina/métodos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Stem Cells ; 37(11): 1441-1454, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31381815

RESUMO

In a previous study, we showed that folate receptor-α (FRα) translocates to the nucleus where it acts as a transcription factor and upregulates Hes1, Oct4, Sox2, and Klf4 genes responsible for pluripotency. Here, we show that acetylation and phosphorylation of FRα favor its nuclear translocation in the presence of folate and can cause a phenotypic switch from differentiated glial cells to dedifferentiated cells. shRNA-FRα mediated knockdown of FRα was used to confirm the role of FRα in dedifferentiation. Ocimum sanctum hydrophilic fraction-1 treatment not only blocks the folate mediated dedifferentiation of glial cells but also promotes redifferentiation of dedifferentiated glial cells, possibly by reducing the nuclear translocation of ~38 kDa FRα and subsequent interaction with chromatin assembly factor-1. Stem Cells 2019;37:1441-1454.


Assuntos
Receptor 1 de Folato/metabolismo , Crista Neural/efeitos dos fármacos , Crista Neural/metabolismo , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Desdiferenciação Celular/efeitos dos fármacos , Desdiferenciação Celular/genética , Linhagem Celular , Linhagem Celular Tumoral , Receptor 1 de Folato/genética , Ácido Fólico/análogos & derivados , Ácido Fólico/farmacologia , Humanos , Técnicas de Transferência Nuclear , Ocimum sanctum/química , Fator 3 de Transcrição de Octâmero/metabolismo , RNA Interferente Pequeno/genética , Fatores de Transcrição SOXB1/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Proc Natl Acad Sci U S A ; 116(35): 17531-17540, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31405972

RESUMO

Folates are critical for central nervous system function. Folate transport is mediated by 3 major pathways, reduced folate carrier (RFC), proton-coupled folate transporter (PCFT), and folate receptor alpha (FRα/Folr1), known to be regulated by ligand-activated nuclear receptors. Cerebral folate delivery primarily occurs at the choroid plexus through FRα and PCFT; inactivation of these transport systems can result in very low folate levels in the cerebrospinal fluid causing childhood neurodegenerative disorders. These disorders have devastating effects in young children, and current therapeutic approaches are not sufficiently effective. Our group has previously reported in vitro that functional expression of RFC at the blood-brain barrier (BBB) and its upregulation by the vitamin D nuclear receptor (VDR) could provide an alternative route for brain folate uptake. In this study, we further demonstrated in vivo, using Folr1 knockout (KO) mice, that loss of FRα led to a substantial decrease of folate delivery to the brain and that pretreatment of Folr1 KO mice with the VDR activating ligand, calcitriol (1,25-dihydroxyvitamin D3), resulted in over a 6-fold increase in [13C5]-5-formyltetrahydrofolate ([13C5]-5-formylTHF) concentration in brain tissues, with levels comparable to wild-type animals. Brain-to-plasma concentration ratio of [13C5]-5-formylTHF was also significantly higher in calcitriol-treated Folr1 KO mice (15-fold), indicating a remarkable enhancement in brain folate delivery. These findings demonstrate that augmenting RFC functional expression at the BBB could effectively compensate for the loss of Folr1-mediated folate uptake at the choroid plexus, providing a therapeutic approach for neurometabolic disorders caused by defective brain folate transport.


Assuntos
Encéfalo/metabolismo , Receptor 1 de Folato/metabolismo , Ácido Fólico/metabolismo , Proteína Carregadora de Folato Reduzido/metabolismo , Vitamina D/metabolismo , Animais , Transporte Biológico , Biomarcadores , Barreira Hematoencefálica/metabolismo , Cromatografia Líquida , Feminino , Receptor 1 de Folato/genética , Expressão Gênica , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Espectrometria de Massas em Tandem
7.
Dev Dyn ; 248(10): 900-917, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31361376

RESUMO

BACKGROUND: Abnormalities in maternal folate and carbohydrate metabolism have both been shown to induce neural tube defects (NTDs) in humans and animal models. Nevertheless, how these two factors might interact in the development of NTDs remains unclear. RESULTS: In specific mouse models and embryo culture systems, we assessed the effects of combining maternal diabetes with mutations in genes involved in folate transport and metabolism (methylenetetrahydrofolate reductase [Mthfr] and folic acid receptor 1 [Folr1]). When maternal hyperglycemia is combined with alterations in folic acid metabolism, there appears to be an increase in the incidence of congenital malformations in the offspring, with NTDs representing the majority of the malformations detected. CONCLUSIONS: The teratogenic effects of diabetes during pregnancy are exacerbated when combined with altered embryonic folate metabolism.


Assuntos
Diabetes Mellitus/genética , Ácido Fólico/metabolismo , Mutação , Defeitos do Tubo Neural/etiologia , Animais , Modelos Animais de Doenças , Técnicas de Cultura Embrionária , Feminino , Receptor 1 de Folato/genética , Ácido Fólico/genética , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Camundongos , Gravidez , Teratogênese
8.
AIDS ; 33(13): 1967-1976, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31259764

RESUMO

OBJECTIVE: Maternal folate (vitamin B9) status is the largest known modifier of neural tube defect risk, so we evaluated folate-related mechanisms of action for dolutegravir (DTG) developmental toxicity. DESIGN: Folate receptor 1 (FOLR1) was examined as a target for DTG developmental toxicity using protein and cellular interaction studies and an animal model. METHODS: FOLR1 competitive binding studies were used to test DTG for FOLR1 antagonism. Human placenta cell line studies were used to test interactions with DTG, folate, and cations. Zebrafish were selected as an animal model to examine DTG-induced developmental toxicity and rescue strategies. RESULTS: FOLR1 binding studies indicate DTG is a noncompetitive FOLR1 antagonist at therapeutic concentrations. In-vitro testing indicates calcium (2 mmol/l) increases FOLR1-folate interactions and alters DTG-FOLR1-folate interactions and cytotoxicity. DTG does not inhibit downstream folate metabolism by dihydrofolate reductase. Early embryonic exposure to DTG is developmentally toxic in zebrafish, and supplemental folic acid can mitigate DTG developmental toxicity. CONCLUSION: Folates and FOLR1 are established modifiers of risk for neural tube defects, and binding data indicates DTG is a partial antagonist of FOLR1. Supplemental folate can ameliorate increased developmental toxicity due to DTG in zebrafish. The results from these studies are expected to inform and guide future animal models and clinical studies of DTG-based antiretroviral therapy in women of childbearing age.


Assuntos
Receptor 1 de Folato/antagonistas & inibidores , Ácido Fólico/administração & dosagem , Compostos Heterocíclicos com 3 Anéis/toxicidade , Proteínas de Peixe-Zebra/antagonistas & inibidores , Peixe-Zebra/embriologia , Animais , Linhagem Celular , Suplementos Nutricionais , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Receptor 1 de Folato/genética , Infecções por HIV/tratamento farmacológico , Inibidores de Integrase de HIV/toxicidade , Humanos , Modelos Animais , Oxazinas , Piperazinas , Gravidez , Piridonas , Testes de Toxicidade , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
9.
Methods Mol Biol ; 1974: 83-98, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31098997

RESUMO

As synthetic small interfering RNA (siRNA) against antitumoral gene targets show promise for cancer treatment, different siRNA delivery systems have sparkled intense investigations. To develop tumor-specific carriers for cytosolic and systemic siRNA delivery, our laboratory has recently generated folate-conjugated targeted combinatorial siRNA polyplexes based on sequence-defined oligomer platform compatible with solid-phase-supported synthesis. These polyplexes presented efficient siRNA-mediated gene silencing in folate receptor-expressing tumors in vitro and in vivo. In this chapter, we provide a brief background on the formulation design and detailed protocols to evaluate polyplex formation, gene silencing efficiency, and receptor-directed cell killing in cancer cells using targeted combinatorial siRNA polyplexes.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Receptor 1 de Folato/genética , Neoplasias/genética , RNA Interferente Pequeno/genética , Linhagem Celular Tumoral , Receptor 1 de Folato/antagonistas & inibidores , Receptor 1 de Folato/química , Ácido Fólico/genética , Inativação Gênica , Humanos , Neoplasias/terapia , Polietilenoglicóis/química , Polímeros/química , RNA Interferente Pequeno/química , RNA Interferente Pequeno/uso terapêutico
10.
J Nutr Biochem ; 69: 1-9, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31035100

RESUMO

Folate-dependent one-carbon cycle metabolism (FOCM) plays a critical role in maintaining genomic stability through regulating DNA biosynthesis, repair and methylation. Folate metabolites as well as other metabolites in the FOCM are hypothesized to be altered when cells transition from normal to cancerous state. Using cells at different stages in their development into colorectal cancer, the FOCM metabolites were profiled as an effort to phenotype the cells, and the metabolite levels were compared to the expressions of related genes. Here, we investigate whether there is a correlation between the metabolite levels, DNA methylation levels and the expression of the related genes that drive the levels of these metabolites. Using CRL1459, APC10.1, HCT116 and Caco-2, we show for the first time that FOCM metabolites correlate with the gene expression patterns. These differences follow a trend that may facilitate distinguishing colon cells at the different stages as they transition into cancerous state. The folate distribution and methionine levels were found to be key in determining the staging of the colon cells in CRC development. Also, expression of CBS, MTRR and MAT genes may facilitate distinguishing between untransformed and transformed colon cells.


Assuntos
Carbono/metabolismo , Colo/patologia , Ácido Fólico/metabolismo , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Transformação Celular Neoplásica , Colo/citologia , Colo/metabolismo , Metilação de DNA , Ferredoxina-NADP Redutase/genética , Receptor 1 de Folato/genética , Ácido Fólico/genética , Ácido Fólico/farmacologia , Regulação da Expressão Gênica , Glicina Hidroximetiltransferase/genética , Células HCT116 , Humanos
11.
J Inherit Metab Dis ; 42(4): 655-672, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30916789

RESUMO

Cerebral folate deficiency is typically defined as a deficiency of the major folate species 5-methyltetrahydrofolate in the cerebrospinal fluid (CSF) in the presence of normal peripheral total folate levels. However, it should be noted that cerebral folate deficiency is also often used to describe conditions where CSF 5-MTHF is low, in the presence of low or undefined peripheral folate levels. Known defects of folate transport are deficiency of the proton coupled folate transporter, associated with systemic as well as cerebral folate deficiency, and deficiency of the folate receptor alpha, leading to an isolated cerebral folate deficiency associated with intractable seizures, developmental delay and/or regression, progressive ataxia and choreoathetoid movement disorders. Inborn errors of folate metabolism include deficiencies of the enzymes methylenetetrahydrofolate reductase, dihydrofolate reductase and 5,10-methenyltetrahydrofolate synthetase. Cerebral folate deficiency is potentially a treatable condition and so prompt recognition of these inborn errors and initiation of appropriate therapy is of paramount importance. Secondary cerebral folate deficiency may be observed in other inherited metabolic diseases, including disorders of the mitochondrial oxidative phosphorylation system, serine deficiency, and pyridoxine dependent epilepsy. Other secondary causes of cerebral folate deficiency include the effects of drugs, immune response activation, toxic insults and oxidative stress. This review describes the absorption, transport and metabolism of folate within the body; analytical methods to measure folate species in blood, plasma and CSF; inherited and acquired causes of cerebral folate deficiency; and possible treatment options in those patients found to have cerebral folate deficiency.


Assuntos
Encefalopatias Metabólicas Congênitas/diagnóstico , Epilepsia/diagnóstico , Deficiência de Ácido Fólico/diagnóstico , Ácido Fólico/uso terapêutico , Tetra-Hidrofolatos/deficiência , Encéfalo/patologia , Encefalopatias Metabólicas Congênitas/líquido cefalorraquidiano , Encefalopatias Metabólicas Congênitas/tratamento farmacológico , Encefalopatias Metabólicas Congênitas/genética , Diagnóstico Diferencial , Epilepsia/líquido cefalorraquidiano , Epilepsia/tratamento farmacológico , Epilepsia/genética , Receptor 1 de Folato/genética , Deficiência de Ácido Fólico/líquido cefalorraquidiano , Deficiência de Ácido Fólico/tratamento farmacológico , Deficiência de Ácido Fólico/genética , Humanos , Tetra-Hidrofolatos/líquido cefalorraquidiano
13.
Int J Oncol ; 54(3): 869-878, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30664189

RESUMO

A significant percentage (~30%) of estrogen receptor­α (ERα)­positive tumors become refractory to endocrine therapies; however, the mechanisms responsible for this resistance remain largely unknown. Chronic exposure to arsenic through foods and contaminated water has been linked to an increased incidence of several tumors and long­term health complications. Preclinical and population studies have indicated that arsenic exposure may interfere with endocrine regulation and increase the risk of breast tumorigenesis. In this study, we examined the effects of sodium arsenite (NaAsIII) exposure in ERα­positive breast cancer cells in vitro and in mammary tumor xenografts. The results revealed that acute (within 4 days) and long­term (10 days to 7 weeks) in vitro exposure to environmentally relevant doses reduced breast cancer 1 (BRCA1) and ERα expression associated with the gain of cyclin D1 (CCND1) and folate receptor 1 (FOLR1), and the loss of methylenetetrahydrofolate reductase (MTHFR) expression. Furthermore, long­term exposure to NaAsIII induced the proliferation and compromised the response of MCF7 cells to tamoxifen (TAM). The in vitro exposure to NaAsIII induced BRCA1 CpG methylation associated with the increased recruitment of DNA methyltransferase 1 (DNMT1) and the loss of RNA polymerase II (PolII) at the BRCA1 gene. Xenografts of NaAsIII­preconditioned MCF7 cells (MCF7NaAsIII) into the mammary fat pads of nude mice produced a larger tumor volume compared to tumors from control MCF7 cells and were more refractory to TAM in association with the reduced expression of BRCA1 and ERα, CpG hypermethylation of estrogen receptor 1 (ESR1) and BRCA1, and the increased expression of FOLR1. These cumulative data support the hypothesis that exposure to AsIII may contribute to reducing the efficacy of endocrine therapy against ERα­positive breast tumors by hampering the expression of ERα and BRCA1 via CpG methylation, respectively of ESR1 and BRCA1.


Assuntos
Antineoplásicos Hormonais/farmacologia , Arsenitos/toxicidade , Proteína BRCA1/genética , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Compostos de Sódio/toxicidade , Tamoxifeno/farmacologia , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Metilação de DNA/efeitos dos fármacos , Exposição Ambiental , Epigênese Genética/efeitos dos fármacos , Feminino , Receptor 1 de Folato/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Regiões Promotoras Genéticas/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Clin Neurosci ; 59: 341-344, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30420205

RESUMO

INTRODUCTION: Folate is essential for production of DNA, neurotransmitters and myelin and regulation of genetic activity. A specific transporter protein is required to transport folate from blood to CSF. Various inherited brain-specific folate transport defects have been recognized due to mutation in Folate Receptor alpha (FOLR1). FOLR1 mutation is one of the vitamin responsive encephalopathies and is inherited as an autosomal recessive condition. It has a wide spectrum of phenotype, commonly presenting as epileptic encephalopathy. Less frequently the condition may manifest with subtle hypotonia, movement disorder as tremors, ataxia or intellectual disability and autistic spectrum disorder. We present a case of folate transporter deficiency with non-epileptic manifestations, presenting with tremors, speech delay and stable white matter changes in MRI brain. OBJECTIVE: We present a case of Folate transporter defect with Non-epileptic presentation. CONCLUSION: Folate transporter deficiency has a wide range of presenting symptoms. Presentation with slowly progressive atypical symptoms, stable white matter changes in brain MRI that does not fit a specific diagnosis, should raise a high suspicion of FOLR1 mutation, even in absence of seizures. Since folate transporter deficiency is a treatable neurodegenerative disorder, early diagnosis and supplementation with folinic acid is vital.


Assuntos
Deficiência de Ácido Fólico/patologia , Síndromes de Malabsorção/patologia , Fenótipo , Encéfalo/metabolismo , Criança , Feminino , Receptor 1 de Folato/genética , Deficiência de Ácido Fólico/diagnóstico por imagem , Deficiência de Ácido Fólico/genética , Humanos , Síndromes de Malabsorção/diagnóstico por imagem , Síndromes de Malabsorção/genética , Mutação
15.
Clin Cancer Res ; 24(20): 5098-5111, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30068707

RESUMO

Purpose: Highly aggressive triple-negative breast cancers (TNBCs) lack validated therapeutic targets and have high risk of metastatic disease. Folate receptor alpha (FRα) is a central mediator of cell growth regulation that could serve as an important target for cancer therapy.Experimental Design: We evaluated FRα expression in breast cancers by genomic (n = 3,414) and IHC (n = 323) analyses and its association with clinical parameters and outcomes. We measured the functional contributions of FRα in TNBC biology by RNA interference and the antitumor functions of an antibody recognizing FRα (MOv18-IgG1), in vitro, and in human TNBC xenograft models.Results: FRα is overexpressed in significant proportions of aggressive basal like/TNBC tumors, and in postneoadjuvant chemotherapy-residual disease associated with a high risk of relapse. Expression is associated with worse overall survival. TNBCs show dysregulated expression of thymidylate synthase, folate hydrolase 1, and methylenetetrahydrofolate reductase, involved in folate metabolism. RNA interference to deplete FRα decreased Src and ERK signaling and resulted in reduction of cell growth. An anti-FRα antibody (MOv18-IgG1) conjugated with a Src inhibitor significantly restricted TNBC xenograft growth. Moreover, MOv18-IgG1 triggered immune-dependent cancer cell death in vitro by human volunteer and breast cancer patient immune cells, and significantly restricted orthotopic and patient-derived xenograft growth.Conclusions: FRα is overexpressed in high-grade TNBC and postchemotherapy residual tumors. It participates in cancer cell signaling and presents a promising target for therapeutic strategies such as ADCs, or passive immunotherapy priming Fc-mediated antitumor immune cell responses. Clin Cancer Res; 24(20); 5098-111. ©2018 AACR.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Receptor 1 de Folato/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Animais , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/genética , Modelos Animais de Doenças , Feminino , Receptor 1 de Folato/genética , Receptor 1 de Folato/metabolismo , Expressão Gênica , Humanos , Imuno-Histoquímica , Camundongos , Modelos Biológicos , Terapia de Alvo Molecular , Neoplasia de Células Basais , Interferência de RNA , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Nucleic Acids Res ; 46(17): 8817-8831, 2018 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-29982651

RESUMO

Astrocytes play crucial roles in the central nervous system, and defects in astrocyte function are closely related to many neurological disorders. Studying the mechanism of gliogenesis has important implications for understanding and treating brain diseases. Epigenetic regulations have essential roles during mammalian brain development. Here, we demonstrate that histone H2A.Z.1 is necessary for the specification of multiple neural precursor cells (NPCs) and has specialized functions that regulate gliogenesis. Depletion of H2A.Z.1 suppresses gliogenesis and results in reduced astrocyte differentiation. Additionally, H2A.Z.1 regulates the acetylation of H3K56 (H3K56ac) by cooperating with the chaperone of ASF1a. Furthermore, RNA-seq data indicate that folate receptor 1 (FOLR1) participates in gliogenesis through the JAK-STAT signaling pathway. Taken together, our results demonstrate that H2A.Z.1 is a key regulator of gliogenesis because it interacts with ASF1a to regulate H3K56ac and then directly affects the expression of FOLR1, which acts as a signal-transducing component of the JAK-STAT signaling pathway.


Assuntos
Receptor 1 de Folato/genética , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Neurogênese/genética , Neuroglia/fisiologia , Acetilação , Animais , Astrócitos/fisiologia , Proteínas de Ciclo Celular , Células Cultivadas , Proteínas Cromossômicas não Histona/metabolismo , Embrião de Mamíferos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Histonas/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Chaperonas Moleculares , Células-Tronco Neurais , Gravidez , Transdução de Sinais/genética , Transcrição Genética
17.
Physiol Res ; 67(3): 417-422, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-30036071

RESUMO

Increased levels of plasma cysteine are associated with obesity and metabolic disturbances. Our recent genetic analyses in spontaneously hypertensive rats (SHR) revealed a mutated Folr1 (folate receptor 1) as the quantitative trait gene associated with diminished renal Folr1 expression, lower plasma folate levels, hypercysteinemia, hyperhomocysteinemia and metabolic disturbances. To further analyse the effects of the Folr1 gene expression on folate metabolism, we used mass spectrometry to quantify folate profiles in the plasma and liver of an SHR-1 congenic strain, with wild type Folr1 allele on the SHR genetic background, and compared them with the SHR strain. In the plasma, concentration of 5-methyltetrahydrofolate (5mTHF) was significantly higher in SHR-1 congenic rats compared to SHR (60+/-6 vs. 42+/-2 nmol/l, P<0.01) and 5mTHF monoglutamate was the predominant form in both strains (>99 % of total folate). In the liver, SHR-1 congenic rats showed a significantly increased level of 5mTHF and decreased concentrations of dihydrofolate (DHF), tetrahydrofolate (THF) and formyl-THF when compared to the SHR strain. We also analysed the extent of folate glutamylation in the liver. Compared with the SHR strain, congenic wild-type Folr1 rats had significantly higher levels of 5mTHF monoglutamate. On the other hand, 5mTHF penta- and hexaglutamates were significantly higher in SHR when compared to SHR-1 rats. This inverse relationship of rat hepatic folate polyglutamate chain length and folate sufficiency was also true for other folate species. These results strongly indicate that the whole body homeostasis of folates is substantially impaired in SHR rats compared to the SHR-1 congenic strain and might be contributing to the associated metabolic disturbances observed in our previous studies.


Assuntos
Receptor 1 de Folato/genética , Deficiência de Ácido Fólico/sangue , Ácido Fólico/sangue , Fígado/metabolismo , Ratos Endogâmicos SHR/genética , Animais , Fígado Gorduroso/metabolismo , Deficiência de Ácido Fólico/genética , Masculino
18.
Med Mol Morphol ; 51(4): 237-243, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29926190

RESUMO

Pancreatic cancer has a poor prognosis; hence, novel prognostic markers and effective therapeutic targets should be identified. We aimed to evaluate folate receptor alpha (FR-α) expression in pancreatic cancer and examine its association with clinicopathological features. We utilized tissue samples from 100 primary pancreatic cancer patients who underwent surgery. FR-α was expressed in 37 of 100 cases (37%). The FR-α-positive group (median, 18.8 months) had a significantly poorer prognosis than the FR-α-negative group [median 21.3 months; HR 1.89 (1.12-3.12); P = 0.017]. These groups were not significantly different regarding progression-free survival (P = 0.196). Furthermore, other serum tumor markers including CA19-9 (mean, 186 vs. 822 U/ml; P = 0.001), Dupan-2 (286 vs. 1133 U/ml; P = 0.000), and Span-1 (69.7 vs. 171.9 U/ml; P = 0.006) were significantly downregulated in the FR-α-positive group. CA19-9 was another prognostic factor, in addition to FR-α, and patient prognosis showed clear stratification curves with the expression of these two molecules. Along with CA19-9, FR-α expression was an independent prognostic factor for the overall survival. FR-α and CA19-9 helped predict patient prognosis based on stratification curves.


Assuntos
Biomarcadores Tumorais/genética , Receptor 1 de Folato/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/terapia , Idoso , Biomarcadores Tumorais/análise , Antígeno CA-19-9 , Feminino , Receptor 1 de Folato/análise , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Prognóstico , Regulação para Cima
19.
Hum Exp Toxicol ; 37(12): 1258-1267, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29644877

RESUMO

The protective effects of folic acid on DNA damage and DNA methylation induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in Kazakh esophageal epithelial cells were investigated using a 3 × 3 factorial design trial. The cells were cultured in vitro and exposed to media containing different concentrations of folic acid and MNNG, after which growth indices were detected. DNA damage levels were measured using comet assays, and genome-wide DNA methylation levels (MLs) were measured using high-performance liquid chromatography. The DNA methylation of methylenetetrahydrofolate reductase (MTHFR) and folate receptor-α (FRα) genes was detected by bisulfite sequencing polymerase chain reaction (PCR). The results showed significant increases in tail DNA concentration, tail length, and Olive tail moment (p < 0.01); a significant reduction of genome-wide DNA MLs (p < 0.01); and an increase in the methylation frequencies of MTHFR and FRα genes. In particular, significant differences were observed in the promoter regions of both genes (p < 0.01). Our study indicated that a reduction in folic acid concentration promotes DNA damage and DNA methylation in Kazakh esophageal epithelial cells upon MNNG exposure. Thus, sufficient folic acid levels could play a protective role against the damage induced by this compound.


Assuntos
Dano ao DNA , Metilação de DNA , Esôfago/efeitos dos fármacos , Ácido Fólico/farmacologia , Metilnitronitrosoguanidina/toxicidade , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Esôfago/metabolismo , Receptor 1 de Folato/genética , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética
20.
Mol Genet Metab ; 124(1): 87-93, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29661558

RESUMO

INTRODUCTION: Cerebral folate deficiency (CFD) syndromes are defined as neuro-psychiatric conditions with low CSF folate and attributed to different causes such as autoantibodies against the folate receptor-alpha (FR) protein that can block folate transport across the choroid plexus, FOLR1 gene mutations or mitochondrial disorders. High-dose folinic acid treatment restores many neurologic deficits. STUDY AIMS AND METHODS: Among 36 patients from 33 families the infantile-onset CFD syndrome was diagnosed based on typical clinical features and low CSF folate. All parents were healthy. Three families had 2 affected siblings, while parents from 4 families were first cousins. We analysed serum FR autoantibodies and the FOLR1 and FOLR2 genes. Among three consanguineous families homozygosity mapping attempted to identify a monogenetic cause. Whole exome sequencing (WES) was performed in the fourth consanguineous family, where two siblings also suffered from polyneuropathy as an atypical finding. RESULTS: Boys (72%) outnumbered girls (28%). Most patients (89%) had serum FR autoantibodies fluctuating over 5-6 weeks. Two children had a genetic FOLR1 variant without pathological significance. Homozygosity mapping failed to detect a single autosomal recessive gene. WES revealed an autosomal recessive polynucleotide kinase 3´phosphatase (PNKP) gene abnormality in the siblings with polyneuropathy. DISCUSSION: Infantile-onset CFD was characterized by serum FR autoantibodies as its predominant pathology whereas pathogenic FOLR1 gene mutations were absent. Homozygosity mapping excluded autosomal recessive inheritance of any single responsible gene. WES in one consanguineous family identified a PNKP gene abnormality that explained the polyneuropathy and also its contribution to the infantile CFD syndrome because the PNKP gene plays a dual role in both neurodevelopment and immune-regulatory function. Further research for candidate genes predisposing to FRα-autoimmunity is suggested to include X-chromosomal and non-coding DNA regions.


Assuntos
Autoanticorpos/sangue , Encefalopatias Metabólicas Congênitas/genética , Receptor 1 de Folato/imunologia , Deficiência de Ácido Fólico/genética , Adolescente , Encefalopatias Metabólicas Congênitas/líquido cefalorraquidiano , Encefalopatias Metabólicas Congênitas/diagnóstico , Criança , Pré-Escolar , Consanguinidade , Enzimas Reparadoras do DNA/genética , Diagnóstico Diferencial , Família , Feminino , Receptor 1 de Folato/genética , Receptor 2 de Folato/genética , Ácido Fólico/líquido cefalorraquidiano , Deficiência de Ácido Fólico/líquido cefalorraquidiano , Deficiência de Ácido Fólico/diagnóstico , Humanos , Lactente , Masculino , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Polineuropatias/etiologia , Sequenciamento Completo do Exoma , Adulto Jovem
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