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1.
J Adv Res ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39341455

RESUMO

INTRODUCTION: Granulosa cells (GCs) is essential for maintaining follicular development. Follicle-stimulating Hormone (FSH) has been demonstrated to effectively promote GCs proliferation, driving the establishment of various superovulation techniques for animal husbandry. However, these techniques face challenges, such as high costs, hormonal imbalances, and an increased risk of early ovarian dysfunction. Therefore, it is important to investigate new methods to improve GCs proliferation. OBJECTIVES: This study aimed to investigate the effect of sulforaphane (SFN) on ovarian GCs proliferation and the underlying mechanisms. METHODS: A comparative transcriptomic analysis of ovaries from the control, SFN, and FSH groups was conducted to identify the primary factors contributing to high proliferative capacity. The role of SFN in the regulation of cell proliferation has been examined in mouse ovarian GCs. Gene interference, overexpression, CUT&TAG technology, and transcriptome analyses were performed to elucidate the underlying mechanisms of the nuclear factor E2-related factor 2 (NRF2)-transketolase (TKT) axis in mediating GCs proliferation. RESULTS: Our research revealed a previously unknown function of SFN, an isothiocyanate of plant origin that is prevalent in cruciferous vegetables, in facilitating the proliferation of mouse ovarian GCs. The efficacy of SFN in enhancing GCs proliferation is similar to that of FSH. At the mechanistic level, SFN promotes NRF2 to transport to the nucleus, which subsequently activates the key enzyme of the non-oxidative pentose phosphate pathway TKT. This activation is instrumental in generating ribose 5-phosphate, a critical precursor for amino acid and nucleotide biosynthesis that underpins the proliferation of GCs. CONCLUSION: Collectively, our findings delineate a novel pathway by which SFN, through the NRF2-TKT axis, enhances the nucleotide pool and thereby supports the proliferation of mouse GCs, presenting novel avenues for exploration in reproductive biology and agricultural sciences.

2.
Biomed Pharmacother ; 176: 116935, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38876050

RESUMO

Breast cancer is one of the most common malignant tumors in women and is a serious threat to women's health. The pentose phosphate pathway (PPP) is a mode of oxidative breakdown of glucose that can be divided into oxidative (oxPPP) and non-oxidative (non-oxPPP) stages and is necessary for cell and body survival. However, abnormal activation of PPP often leads to proliferation, migration, invasion, and chemotherapy resistance in breast cancer. Glucose-6-phosphate dehydrogenase (G6PD) is the rate-limiting enzyme in PPP oxidation. Nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) produced by G6PD is the raw material for cholesterol and lipid synthesis and can resist the production of oxygen species (ROS) and reduce oxidative stress damage to tumor cells. Transketolase (TKT) is a key enzyme in non-oxPPP. Ribose 5-phosphate (R5P), produced by TKT, is a raw material for DNA and RNA synthesis, and is essential for tumor cell proliferation and DNA damage repair. In this review, we describe the role and specific mechanism of the PPP and the two most important enzymes of the PPP, G6PD and TKT, in the malignant progression of breast cancer, providing strategies for future clinical treatment of breast cancer and a theoretical basis for breast cancer research.


Assuntos
Neoplasias da Mama , Progressão da Doença , Glucosefosfato Desidrogenase , Via de Pentose Fosfato , Transcetolase , Transcetolase/metabolismo , Humanos , Neoplasias da Mama/patologia , Neoplasias da Mama/enzimologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Feminino , Glucosefosfato Desidrogenase/metabolismo , Via de Pentose Fosfato/efeitos dos fármacos , Animais
3.
J Biochem Mol Toxicol ; 37(12): e23487, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37718545

RESUMO

Resistance to chemotherapy in cancer leads to poor therapeutic outcomes and also leads to challenges in treatment. The present work evaluated the mechanism involved in the resistance of 5-flurouracil (5-FU) in pancreatic cancer. At least 14 different pancreatic cancer (PC) cell lines were used for the study. For in vivo study female nude mice were selected. Patient-derived tumor xenograft samples were obtained from patients. The study involved, study for glucose uptake, fluorescence-activated cell sorting for glucose transporter, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide for cell survival, Picto-micrography for clonogenic assay, glutamine uptake assay, extracellular acidification and oxygen consumption rate, carbon dioxide release assay and lactate assay were also done. In addition to this, quantitative real-time polymerase chain reaction analysis for expression of genes, chromatin immunoprecipitation assay, western blot for protein expression, and immunohistochemical analysis in tumor sections, the tumors were studied by imaging for hypoxia and localization of TKT and CTPS-2. Also, patient-derived xenograft tumors were engrafted in nude mice, followed by a glucose uptake assay. We reported that elevated glycolytic flux causes dependence on glucose in cancer cells and, at the same time, increases pyrimidine biosynthesis. It was also found that stem cell factor-mediated stabilization of hypoxia-inducible factor-1a (HIF-1α) modulates the resistance in PC. Targeting HIF-1α in combination with 5-FU, strongly reduced the tumor burden. The study concludes that stem cell factor modulates HIF-1α and decreases the sensitivity in 5-FU resistant pancreatic cancer cells by targeting glucose metabolism. Deceased expression levels of CTPS-2 and TKT, which are regulators of pyrimidine biosynthesis could better the chance of survival in patients of pancreatic cancer receiving treatment of 5-FU.


Assuntos
Neoplasias Pancreáticas , Fator de Células-Tronco , Animais , Camundongos , Humanos , Feminino , Camundongos Nus , Fator de Células-Tronco/uso terapêutico , Neoplasias Pancreáticas/metabolismo , Glucose/metabolismo , Hipóxia , Linhagem Celular Tumoral , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Pirimidinas , Subunidade alfa do Fator 1 Induzível por Hipóxia
4.
J Clin Med ; 12(3)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36769572

RESUMO

Proper horizontal and vertical thickness of the gingival connective tissue has been proven to be one of the success criteria in dental implant and reconstructive surgery. When thin tissue is found, gingiva augmentation methods can be used to increase the quality and volume of the tissue. Many methods have been described, among them pedicle soft-tissue flaps or autogenic tissue grafts. As an alternative to patients' own tissue, xenogenic materials can be used for grafting. The fundamental issue is to choose a material that will ensure the maximum therapeutic effect, while also minimizing the negative influence on the patient's health. The aim of this study was to compare gingival augmentation procedures using a palatal connective tissue graft (CTG) and an xenogenic soft-tissue substitute, Geistlich Mucograft (xenogeneic collagen matrix; CMX), and assess whether the timing of the graft surgery influences the clinical outcomes. The original study was a randomized control trial with a total of 75 implants placed. The patients received the soft-tissue thickening 3 months before the implant placement or 3 months after the implant placement (depending on the group). A connective tissue graft (CTG) or Geistlich Mucograft were used (depending on the group). For both the CTG and Geistlich Mucograft, better clinical outcomes were observed for maintaining the alveolar bone level and the thickness of the attached gingiva compared to the control group with no gingival augmentation. The Geistlich Mucograft showed good clinical performance in comparison to the control. Soft-tissue augmentation with the CTG before the implant placement was found to be most efficient method in terms of a stable increase of the tissue thickness since, throughout the entire observation period, the greatest increase of 1.035 mm (SD = 0.73 mm) in thickness was observed. Statistically important differences in the tissue thickness baseline compared after 5 years were observed for groups G1 vs. G2b (no augmentation vs. CTG before), G1 vs. G3b (no augmentation vs. CTG after) and for groups G2b vs. G3a (CTG before vs. CMX after).

5.
J Endocrinol ; 256(3)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36449405

RESUMO

Transketolase (TKT), an enzyme in the non-oxidative branch of the pentose phosphate pathway (PPP), bi-directionally regulates the carbon flux between the PPP and glycolysis. Loss of TKT in adipose tissues decreased glycolysis and increased lipolysis and uncoupling protein-1 (UCP1) expression, protecting mice from high-fat diet-induced obesity. However, the role of TKT in brown adipose tissue (BAT)-dependent glucose homeostasis under normal chow diet remains to be elucidated. We found that TKT ablation increased levels of glucose transporter 4 (GLUT4), promoting glucose uptake and glycogen accumulation in BAT. Using the streptozotocin (STZ)-induced diabetic mouse model, we discovered that enhanced glucose uptake due to TKT deficiency in BAT contributed to decreasing blood glucose and weight loss, protecting mice from STZ-induced diabetes. Mechanistically, TKT deficiency decreased the level of thioredoxin-interacting protein, a known inhibitor for GLUT4, by decreasing NADPH and glutathione levels and inducing oxidative stress in BAT. Therefore, our data reveal a new role of TKT in regulating the anti-diabetic function of BAT as well as glucose homeostasis.


Assuntos
Tecido Adiposo Marrom , Diabetes Mellitus Experimental , Camundongos , Animais , Tecido Adiposo Marrom/metabolismo , Transcetolase/metabolismo , Glicólise , Diabetes Mellitus Experimental/metabolismo , Glucose/metabolismo
6.
Biomed Pharmacother ; 154: 113607, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36030587

RESUMO

Transketolase (TKT) is an enzyme that is ubiquitously expressed in all living organisms and has been identified as an important regulator of cancer. Recent studies have shown that the TKT family includes the TKT gene and two TKT-like (TKTL) genes; TKTL1 and TKTL2. TKT and TKTL1 have been reported to be involved in the regulation of multiple cancer-related events, such as cancer cell proliferation, metastasis, invasion, epithelial-mesenchymal transition, chemoradiotherapy resistance, and patient survival and prognosis. Therefore, TKT may be an ideal target for cancer treatment. More importantly, the levels of TKTL1 were detected using EDIM technology for the early detection of some malignancies, and TKTL1 was more sensitive and specific than traditional tumor markers. Detecting TKTL1 levels before and after surgery could be used to evaluate the surgery's effect. While targeted TKT suppresses cancer in multiple ways, in some cases, it has detrimental effects on the organism. In this review, we discuss the role of TKT in different tumors and the detailed mechanisms while evaluating its value and limitations in clinical applications. Therefore, this review provides a basis for the clinical application of targeted therapy for TKT in the future, and a strategy for subsequent cancer-related research.


Assuntos
Neoplasias , Transcetolase , Biomarcadores Tumorais/genética , Proliferação de Células , Humanos , Neoplasias/terapia , Transcetolase/genética
7.
Redox Biol ; 54: 102379, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35779441

RESUMO

The Pentose Phosphate Pathway (PPP), a metabolic offshoot of the glycolytic pathway, provides protective metabolites and molecules essential for cell redox balance and survival. Transketolase (TKT) is the critical enzyme that controls the extent of "traffic flow" through the PPP. Here, we explored the role of TKT in maintaining the health of the human retina. We found that Müller cells were the primary retinal cell type expressing TKT in the human retina. We further explored the role of TKT in human Müller cells by knocking down its expression in primary cultured Müller cells (huPMCs), isolated from the human retina (11 human donors in total), under light-induced oxidative stress. TKT knockdown and light stress reduced TKT enzymatic activities and the overall metabolic activities of huPMCs with no detectable cell death. TKT knockdown restrained the PPP traffic flow, reduced the expression of NAD(P)H Quinone Dehydrogenase 1 (NQO1), impaired the antioxidative response of NRF2 to light stress and aggravated the endoplasmic reticulum (ER) stress. TKT knockdown also inhibited overall glucose intake, reduced expression of Dihydrolipoamide dehydrogenase (DLD) and impaired the energy supply of the huPMCs. In summary, Müller cell-mediated TKT activity plays a critical protective role in the stressed retina. Knockdown of TKT disrupted the PPP and impaired overall glucose utilisation by huPMCs and rendered huPMCs more vulnerable to light stress by impairing energy supply and antioxidative NRF2 responses.


Assuntos
Fator 2 Relacionado a NF-E2 , Transcetolase , Células Ependimogliais/metabolismo , Glucose/metabolismo , Humanos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Via de Pentose Fosfato , Pentoses , Fosfatos , Transcetolase/genética , Transcetolase/metabolismo
8.
Biochem Biophys Res Commun ; 615: 9-16, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35679751

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy driven by genetic mutations and/or epigenetic dysregulation. Gemcitabine chemotherapy is the first-line regimen for pancreatic cancer but has limited efficacy. Our previous study revealed the role of SETD2-H3K36me3 loss in the initiation and metastasis of PDAC, but little is known about its role in tumor metabolism. Here, we found that SETD2-deficient PDAC enhanced glycolysis addiction via upregulation of glucose transporter 1 (GLUT1) to meet its large demand for glucose in progression. Moreover, SETD2 deficiency impaired nucleoside synthesis by directly downregulating the transcriptional level of transketolase (TKT) in the pentose phosphate pathway. The metabolic changes confer SETD2-deficient PDAC cells with increased sensitivity to gemcitabine under glycolysis restriction conditions. Collectively, our study provides mechanistic insights into how SETD2 deficiency reprograms glycolytic metabolism to compensate for insufficient nucleoside synthesis, suggesting that glycolysis restriction combined with gemcitabine might be a potential therapeutic strategy for PDAC patients with SETD2 deficiency.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Glicólise , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Via de Pentose Fosfato , Gencitabina , Neoplasias Pancreáticas
9.
Acta Pharm Sin B ; 12(2): 558-580, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35256934

RESUMO

Hepatocellular carcinoma (HCC) is an aggressive human cancer with increasing incidence worldwide. Multiple efforts have been made to explore pharmaceutical therapies to treat HCC, such as targeted tyrosine kinase inhibitors, immune based therapies and combination of chemotherapy. However, limitations exist in current strategies including chemoresistance for instance. Tumor initiation and progression is driven by reprogramming of metabolism, in particular during HCC development. Recently, metabolic associated fatty liver disease (MAFLD), a reappraisal of new nomenclature for non-alcoholic fatty liver disease (NAFLD), indicates growing appreciation of metabolism in the pathogenesis of liver disease, including HCC, thereby suggesting new strategies by targeting abnormal metabolism for HCC treatment. In this review, we introduce directions by highlighting the metabolic targets in glucose, fatty acid, amino acid and glutamine metabolism, which are suitable for HCC pharmaceutical intervention. We also summarize and discuss current pharmaceutical agents and studies targeting deregulated metabolism during HCC treatment. Furthermore, opportunities and challenges in the discovery and development of HCC therapy targeting metabolism are discussed.

10.
Diagnostics (Basel) ; 11(6)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205023

RESUMO

Ovarian cancer remains the gynecological cancer with the highest mortality rate. In our study, we compare a number of proteins from different effector pathways to assess their usefulness in the diagnosis of ovarian cancer. The tissue expression of the tested proteins was assessed by two methods: qRT-PCR and an immunohistochemical analysis. A significantly higher level of mRNA expression was found in the ovarian cancer group for YAP and TEAD4 (p = 0.004 and p = 0.003, respectively). There was no statistical significance in the expression of mRNA for SMAD3, and there was borderline statistical significance for SMAD2 between the groups of ovarian cancer patients and other subgroups of patients with simple cysts and healthy ovarian tissue (p = 0.726 and p = 0.046, respectively). Significantly higher levels of transferrin receptor (CD71), H2A.X, and ADH1A gene expression were found in the ovarian cancer group compared to the control group for YAP, and TEAD4 showed strong nuclear and cytoplasmic staining in ovarian carcinoma and weak staining in non-carcinoma ovarian samples, ADH1A1 showed strong staining in the cytoplasm of carcinoma sections and a weak positive reaction in the non-carcinoma section, H2A.X showed strong positive nuclear staining in carcinoma sections and moderate positive staining in non-carcinoma samples, and CD71 showed moderate positive staining in carcinoma and non-carcinoma samples. YAP, TEAD4, and ADH1A proteins appear to be promising biomarkers in the diagnosis of ovarian cancer.

11.
Theranostics ; 11(11): 5232-5247, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859744

RESUMO

Rationale: NRF2, a redox sensitive transcription factor, is up-regulated in head and neck squamous cell carcinoma (HNSCC), however, the associated impact and regulatory mechanisms remain unclear. Methods: The protein expression of NRF2 in HNSCC specimens was examined by IHC. The regulatory effect of c-MYC on NRF2 was validated by ChIP-qPCR, RT-qPCR and western blot. The impacts of NRF2 on malignant progression of HNSCC were determined through genetic manipulation and pharmacological inhibition in vitro and in vivo. The gene-set enrichment analysis (GSEA) on expression data of cDNA microarray combined with ChIP-qPCR, RT-qPCR, western blot, transwell migration/ invasion, cell proliferation and soft agar colony formation assays were used to investigate the regulatory mechanisms of NRF2. Results: NRF2 expression is positively correlated with malignant features of HNSCC. In addition, carcinogens, such as nicotine and arecoline, trigger c-MYC-directed NRF2 activation in HNSCC cells. NRF2 reprograms a wide range of cancer metabolic pathways and the most notable is the pentose phosphate pathway (PPP). Furthermore, glucose-6-phosphate dehydrogenase (G6PD) and transketolase (TKT) are critical downstream effectors of NRF2 that drive malignant progression of HNSCC; the coherently expressed signature NRF2/G6PD/TKT gene set is a potential prognostic biomarker for prediction of patient overall survival. Notably, G6PD- and TKT-regulated nucleotide biosynthesis is more important than redox regulation in determining malignant progression of HNSCC. Conclusions: Carcinogens trigger c-MYC-directed NRF2 activation. Over-activation of NRF2 promotes malignant progression of HNSCC through reprogramming G6PD- and TKT-mediated nucleotide biosynthesis. Targeting NRF2-directed cellular metabolism is an effective strategy for development of novel treatments for head and neck cancer.


Assuntos
Glucosefosfato Desidrogenase/genética , Neoplasias de Cabeça e Pescoço/genética , Fator 2 Relacionado a NF-E2/genética , Proteínas Proto-Oncogênicas c-myc/genética , Transcetolase/genética , Biomarcadores Tumorais/genética , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Redes e Vias Metabólicas/genética , Oxirredução , Via de Pentose Fosfato/genética , Prognóstico , Transdução de Sinais/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
12.
Biotechnol Rep (Amst) ; 24: e00378, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31641622

RESUMO

Succinic acid is an important acid which is used in medicine and pharmaceutical companies. Metabolically engineered Escherichia coli strain was used for the effective production of succinic acid using Cocos nucifera water, which contained 5.00 ± 0.02 g/L glucose, 6.10 ± 0.01 g /L fructose and 6.70 ± 0.02 g /L sucrose. Fermentation of C. nucifera water with E. coli M6PM produced a final concentration of 11.78 ± 0.02 g/L succinic acid and yield of 1.23 ± 0.01 mol/mol, 0.66 ± 0.01 g/g total sugars after 72 h dual-phase fermentation in M9 medium while modeled sugar was 0.38 ± 0.02 mol/mol total sugars. It resulted in 72% of the maximum theoretical yield of succinic acid. Here we show that novel substrate of C. nucifera water resulted in effective production of succinic acid. These investigations unveil the importance of C. nucifera water as a substrate for the production of biochemicals.

13.
Pathol Oncol Res ; 25(4): 1423-1429, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30357756

RESUMO

To analyze putative biomarkers for prostate cancer (PCA) characterization, the second leading cause of cancer-associated mortality in men. Quantification of the expression level of c-myc and HIF-1α was performed in 72 prostate cancer specimens. A cohort of 497 prostate cancer patients from The Cancer Genome Atlas (TCGA) database was further analyzed, in order to test our hypothesis. We found that high c-myc level was significantly associated with HIF-1α elevated expression (p = 0.008) in our 72 samples. Statistical analysis of 497 TCGA prostate cancer specimens confirmed the strong association (p = 0.0005) of c-myc and HIF-1α expression levels, as we found in our series. Moreover, we found high c-myc levels significantly associated with low Glutatione S-transferase P1 (GSTP1) expression (p = 0.01), with high Transketolase (TKT) expression (p < 0.0001). High TKT levels were found in TCGA samples with low GSTP1 mRNA (p < 0.0001), as shown for c-myc, and with ERG increased expression (p = 0.02). Finally, samples with low GSTP1 expression displayed higher ERG mRNA levels than samples with high GSTP1 score (p < 0.0001), as above shown for c-myc. Our study emphasizes the notion of a potential value of HIF-1α and c-myc as putative biomarkers in prostate cancer; moreover TCGA data analysis showed a putative crosstalk between c-myc, HIF-1α, ERG, TKT, and GSTP1, suggesting a potential use of this axis in prostate cancer.


Assuntos
Biomarcadores Tumorais/genética , Glutationa S-Transferase pi/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas c-myc/genética , Transcetolase/genética , Idoso , Estudos de Coortes , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Próstata/patologia , Regulador Transcricional ERG/genética
14.
J Investig Med ; 66(5): 1-9, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29502067

RESUMO

This study tested the hypothesis that the effects of lovastatin on anaplastic thyroid cancer cell growth are mediated by upregulation of transketolase (TKT) expression. The effects of lovastatin on TKT protein levels in ARO cells were determined using western blot and proteomic analyses. After treatment with lovastatin and oxythiamine, the in vitro and in vivo growth of ARO cells was determined using 3-(4,5-Dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assays and tumor xenografts in nude mice. TKT protein expression in the ARO tumors was assessed using immunohistochemistry analysis. Proteomic analysis revealed that 25 µM lovastatin upregulated TKT expression. Co-treatment of ARO cells with 1 µM lovastatin + 1 µM oxythiamine increased TKT protein expression compared with control levels; however, no differences were observed with 10 µM lovastatin + 1 µM oxythiamine. Furthermore, treatment with either oxythiamine or lovastatin alone reduced ARO tumor expression of TKT, as well as decreased ARO cell proliferation in vitro and tumor growth in vivo. However, mice treated with both lovastatin and oxythiamine at the same time had tumor volumes similar to that of the untreated control group. We conclude that either lovastatin or oxythiamine reduced ARO cell growth; however, the combination of these drugs resulted in antagonism of ARO tumor growth.


Assuntos
Lovastatina/uso terapêutico , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Carcinoma Anaplásico da Tireoide/patologia , Transcetolase/metabolismo , Animais , Apoptose/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Lovastatina/farmacologia , Masculino , Camundongos Nus , Oxitiamina/farmacologia , Proteômica , Carcinoma Anaplásico da Tireoide/enzimologia , Carga Tumoral/efeitos dos fármacos
15.
Am J Hum Genet ; 98(6): 1235-1242, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27259054

RESUMO

Whole-exome sequencing (WES) is increasingly being utilized to diagnose individuals with undiagnosed disorders. Developmental delay and short stature are common clinical indications for WES. We performed WES in three families, using proband-parent trios and two additional affected siblings. We identified a syndrome due to an autosomal-recessively inherited deficiency of transketolase, encoded by TKT, on chromosome 3p21. Our series includes three families with a total of five affected individuals, ranging in age from 4 to 25 years. Two families of Ashkenazi Jewish ancestry were homozygous for an 18 base pair in-frame insertion in TKT. The third family was compound heterozygous for nonsense and missense variants in TKT. All affected individuals had short stature and were developmentally delayed. Congenital heart defects were noted in four of the five affected individuals, and there was a history of chronic diarrhea and cataracts in the older individuals with the homozygous 18 base pair insertion. Enzymatic testing confirmed significantly reduced transketolase activity. Elevated urinary excretion of erythritol, arabitol, ribitol, and pent(ul)ose-5-phosphates was detected, as well as elevated amounts of erythritol, arabitol, and ribitol in the plasma of affected individuals. Transketolase deficiency reduces NADPH synthesis and nucleic acid synthesis and cell division and could explain the problems with growth. NADPH is also critical for maintaining cerebral glutathione, which might contribute to the neurodevelopmental delays. Transketolase deficiency is one of a growing list of inborn errors of metabolism in the non-oxidative part of the pentose phosphate pathway.


Assuntos
Deficiências do Desenvolvimento/etiologia , Nanismo/etiologia , Cardiopatias Congênitas/etiologia , Mutação/genética , Transcetolase/genética , Adulto , Criança , Pré-Escolar , Deficiências do Desenvolvimento/metabolismo , Deficiências do Desenvolvimento/patologia , Nanismo/metabolismo , Nanismo/patologia , Feminino , Glutationa/metabolismo , Cardiopatias Congênitas/metabolismo , Cardiopatias Congênitas/patologia , Humanos , Masculino , NADP/metabolismo , Linhagem , Síndrome , Adulto Jovem
16.
Proc Natl Acad Sci U S A ; 113(6): E725-34, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26811478

RESUMO

Cancer cells experience an increase in oxidative stress. The pentose phosphate pathway (PPP) is a major biochemical pathway that generates antioxidant NADPH. Here, we show that transketolase (TKT), an enzyme in the PPP, is required for cancer growth because of its ability to affect the production of NAPDH to counteract oxidative stress. We show that TKT expression is tightly regulated by the Nuclear Factor, Erythroid 2-Like 2 (NRF2)/Kelch-Like ECH-Associated Protein 1 (KEAP1)/BTB and CNC Homolog 1 (BACH1) oxidative stress sensor pathway in cancers. Disturbing the redox homeostasis of cancer cells by genetic knockdown or pharmacologic inhibition of TKT sensitizes cancer cells to existing targeted therapy (Sorafenib). Our study strengthens the notion that antioxidants are beneficial to cancer growth and highlights the therapeutic benefits of targeting pathways that generate antioxidants.


Assuntos
Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/patologia , Estresse Oxidativo , Transcetolase/metabolismo , Animais , Sequência de Bases , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Glutationa/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Masculino , Metaboloma/efeitos dos fármacos , Camundongos Nus , Dados de Sequência Molecular , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Via de Pentose Fosfato/efeitos dos fármacos , Peróxidos/farmacologia , Compostos de Fenilureia/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sorafenibe , Transcetolase/antagonistas & inibidores , Transcetolase/genética , Regulação para Cima/efeitos dos fármacos
17.
Cancer Biol Ther ; 16(3): 484-92, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25701261

RESUMO

Diabetes is a risk factor for breast cancer development and is associated with poor prognosis for breast cancer patients. However, the molecular and biochemical mechanisms underlying the association between diabetes and breast cancer have not been fully elucidated. Here, we investigated estradiol response in MCF-7 breast cancer cells with or without chronic exposure to insulin. We found that insulin priming is necessary and specific for estradiol-induced cancer cell growth, and induces anaplerotic shunting of glucose into macromolecule biosynthesis in the estradiol treated cells. Treatment with ERK or Akt specific inhibitors, U0126 or LY294002, respectively, suppressed estradiol-induced growth. Interestingly, molecular analysis revealed that estradiol treatment markedly increases expression of cyclin A and B, and decreases p21 and p27 in the insulin-primed cells. In addition, estradiol treatment activated metabolic genes in pentose phosphate (PPP) and serine biosynthesis pathways in the insulin-primed cells while insulin priming decreased metabolic gene expression associated with glucose catabolism in the breast cancer cells. Finally, we found that anti-diabetic drug metformin and AMPK ligand AICAR, but not thiazolidinediones (TZDs), specifically suppress the estradiol-induced cellular growth in the insulin-primed cells. These findings suggest that estrogen receptor (ER) activation under chronic hyperinsulinemic condition increases breast cancer growth through the modulation of cell cycle and apoptotic factors and nutrient metabolism, and further provide a mechanistic evidence for the clinical benefit of metformin use for ER-positive breast cancer patients with diabetes.


Assuntos
Neoplasias da Mama/metabolismo , Complicações do Diabetes/metabolismo , Diabetes Mellitus/tratamento farmacológico , Estradiol/administração & dosagem , Receptor alfa de Estrogênio/biossíntese , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/complicações , Neoplasias da Mama/etiologia , Butadienos/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Cromonas/administração & dosagem , Complicações do Diabetes/induzido quimicamente , Complicações do Diabetes/etiologia , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Estradiol/efeitos adversos , Receptor alfa de Estrogênio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Humanos , Insulina/administração & dosagem , Insulina/metabolismo , Células MCF-7 , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Morfolinas/administração & dosagem , Nitrilas/administração & dosagem , Proteína Oncogênica v-akt/antagonistas & inibidores , Fatores de Risco
18.
Eur J Med Genet ; 57(10): 543-51, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25078763

RESUMO

We identified six patients presenting with a strikingly similar clinical phenotype of profound syndromic intellectual disability of unknown etiology. All patients lived in the same village. Extensive genealogical work revealed that the healthy parents of the patients were all distantly related to a common ancestor from the 17th century, suggesting autosomal recessive inheritance. In addition to intellectual disability, the clinical features included hypotonia, strabismus, difficulty to fix the eyes to an object, planovalgus in the feet, mild contractures in elbow joints, interphalangeal joint hypermobility and coarse facial features that develop gradually during childhood. The clinical phenotype did not fit any known syndrome. Genome-wide SNP genotyping of the patients and genetic mapping revealed the longest shared homozygosity at 3p22.1-3p21.1 encompassing 11.5 Mb, with no other credible candidate loci emerging. Single point parametric linkage analysis showed logarithm of the odds score of 11 for the homozygous region, thus identifying a novel intellectual disability predisposition locus. Whole-genome sequencing of one affected individual pinpointed three genes with potentially protein damaging homozygous sequence changes within the predisposition locus: transketolase (TKT), prolyl 4-hydroxylase transmembrane (P4HTM), and ubiquitin specific peptidase 4 (USP4). The changes were found in heterozygous form with 0.3-0.7% allele frequencies in 402 whole-genome sequenced controls from the north-east of Finland. No homozygotes were found in this nor additional control data sets. Our study facilitates clinical and molecular diagnosis of patients with this novel autosomal recessive intellectual disability syndrome. However, further studies are needed to unambiguously identify the underlying genetic defect.


Assuntos
Cromossomos Humanos Par 3 , Deficiência Intelectual/genética , Adolescente , Adulto , Análise Mutacional de DNA , Anormalidades do Olho/genética , Feminino , Finlândia , Genes Recessivos , Heterogeneidade Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Hipotonia Muscular/genética , Linhagem , Fenótipo , Prolil Hidroxilases/genética , Análise de Sequência de DNA , Síndrome , Transcetolase/deficiência , Transcetolase/genética , Ubiquitina Tiolesterase/genética , Proteases Específicas de Ubiquitina , Adulto Jovem
19.
FEMS Microbiol Lett ; 358(1): 30-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25047872

RESUMO

Improved genetic tools are required to identify new drug targets in Mycobacterium tuberculosis. To this aim, genetic approaches, targeting either transcription and/or protein degradation, have been developed to appraise gene essentiality and to test the impact of gene silencing on bacterial survival. Here, we successfully combined the Tet-Pip OFF system, which downregulates transcription through the TetR and Pip repressors, with SspB-mediated protein degradation to study depletion of the transketolase encoded by the tkt (rv1449c) gene. We show that depletion of Tkt using the RNA silencing and protein degradation (RSPD) system arrested growth of M. tuberculosis in vitro faster than the Tet-Pip OFF system alone. In addition, we extended the new combined approach to an ex vivo model of M. tuberculosis infection in THP-1 cells. Tkt-depleted bacteria displayed reduced virulence as compared to wild type bacilli, thus confirming the essentiality of the enzyme for intracellular growth.


Assuntos
Genes Essenciais , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/fisiologia , Proteólise , Transcetolase/genética , Transcetolase/metabolismo , Linhagem Celular , Inativação Gênica , Humanos , Viabilidade Microbiana , Monócitos/microbiologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crescimento & desenvolvimento , Virulência
20.
J Proteomics ; 89: 227-37, 2013 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-23665002

RESUMO

Lung cancer (LC) and chronic obstructive pulmonary disease (COPD) commonly coexist in smokers, and the presence of COPD increases the risk of developing LC. The aim of this study was to identify distinct proteomic profiles able to discriminate these two pathological entities. Protein content was assessed in the bronchoalveolar lavage (BAL) of 60 patients classified in four groups: COPD, COPD and LC, LC without COPD, and control with neither COPD nor LC. Proteins were separated into spots by bidimensional polyacrylamide gel electrophoresis (2D-PAGE) and examined by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/TOF). A total of 40 proteins were differentially expressed in the LC and/or COPD groups as compared with the control group. Distinct protein profiles were identified and validated for each pathological entity (LC and COPD). The main networks involved were related to inflammatory signalling, free radical scavenging and oxidative stress response, and glycolysis and gluconeogenesis pathways. The most relevant signalling link between LC and COPD was through the NF-κB pathway. In conclusion, the protein profiles identified contribute to elucidate the underlying pathogenic pathways of both diseases, and provide new tools of potential use as biomarkers for the early diagnosis of LC. BIOLOGICAL SIGNIFICANCE: Sequence coverage. The protein sequence coverage (95%) was estimated for specific proteins by the percentage of matching amino acids from the identified peptides having confidence greater than or equal to 95% divided by the total number of amino acids in the sequence. Ingenuity Pathways Analysis. Mapping of our proteins onto biological pathways and disease networks demonstrated that 22 proteins were linked to inflammatory signalling (p-value: 1.35 10(-08)-1.42 10(-02)), 15 proteins were associated with free radical scavenging and oxidative stress response (p-value: 4.93 10(-11)-1.27 10(-02)), and 9 proteins were related with glycolysis and gluconeogenesis pathways (p-value: 7.39 10(-09)-1.58 10(-02)).


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/metabolismo , Proteômica , Doença Pulmonar Obstrutiva Crônica/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletroforese em Gel Bidimensional , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/patologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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