RESUMO
The phenolic metabolite of benzene, hydroquinone (HQ), has potential risks for hematological disorders and hematotoxicity in humans. Previous studies have revealed that reactive oxygen species, DNA methylation, and histone acetylation participate in benzene metabolites inhibiting erythroid differentiation in hemin-induced K562 cells. GATA1 and GATA2 are crucial erythroid-specific transcription factors that exhibit dynamic expression patterns during erythroid differentiation. We investigated the role of GATA factors in HQ-inhibited erythroid differentiation in K562 cells. When K562 cells were induced with 40 µM hemin for 0-120 h, the mRNA and protein levels of GATA1 and GATA2 changed dynamically. After exposure to 40 µM HQ for 72 h, K562 cells were induced with 40 µM hemin for 48 h. HQ considerably reduced the percentage of hemin-induced Hb-positive cells, decreased the GATA1 mRNA, protein, and occupancy levels at α-globin and ß-globin gene clusters, and increased the GATA2 mRNA and protein levels significantly. ChIP-seq analysis revealed that HQ reduced GATA1 occupancy, and increased GATA2 occupancy at most gene loci in hemin-induced K562 cells. And GATA1 and GATA2 might play essential roles in the erythroid differentiation protein interaction network. These results elucidate that HQ decreases GATA1 occupancy and increases GATA2 occupancy at the erythroid gene loci, thereby downregulating GATA1 and upregulating GATA2 expression, which in turn modulates the expression of erythroid genes and inhibits erythroid differentiation. This partially explains the mechanism of benzene hematotoxicity.
Assuntos
Benzeno , Hemina , Humanos , Células K562 , Benzeno/toxicidade , Hemina/farmacologia , Hidroquinonas/toxicidade , Diferenciação Celular , Fator de Transcrição GATA1/genética , RNA MensageiroRESUMO
Inevitable emergence of drug resistance is the biggest hurdle to both chemotherapies and targeted therapies. Understanding the resistance mechanisms will contribute to identification of biomarkers for predicting response to therapy and design new therapeutic strategies to overcome drug resistance in human cancers. The type II transforming growth factor (TGF)-ß receptor gene (TGFBR2) is frequently frameshift mutated in several cancer types, especially in colorectal, endometrium and gastric cancers cells. Here, we found that Med12, a component of the transcriptional mediator complex, plays a role in modulating chemosensitivity in TGFBR2 deficient cancer cells. Loss of Med12 leads to chemoresistance in multiple TGFBR2 deficient cancer cells. Interestingly, RNA sequencing data revealed that interferon IFN-related DNA damage resistance signature (IRDS) is upregulated in Med12 knockdown cancer cells. And the expression of IRDS pattern is negatively correlated with chemosensitivity. Therefore, our study identifies a novel mechanism of Med12-mediated drug resistance, which is a TGFBR-independent manner.
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Complexo Mediador , Neoplasias , Receptor do Fator de Crescimento Transformador beta Tipo II , Resistencia a Medicamentos Antineoplásicos , Humanos , Complexo Mediador/genética , Complexo Mediador/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismoRESUMO
OBJECTIVE: To determine the impact of preoperative stent placement on postradiotherapy stricture rate in patients with cervical cancer after radical resection. METHODS: This study was a retrospective analysis of data collected from 55 cervical cancer patients treated with radiotherapy between June 2016 and June 2020. Patients were divided into the stent and control groups. After 3 months, the stricture rate and the complications related to stent placement between the two groups were compared. RESULTS: There were 12 (46.2%) and 10 (34.5%) cases of ureteral stricture in the stent (n = 26) and control (n = 29) groups, respectively, three months after the end of radiotherapy. The incidence rates of ureter stricture in the two groups were not significantly different (P = 0.378). Moreover, there were 20 units (38.5%) and 15 units (25.9%) ureteral strictures in the stent and control groups, respectively. No significant difference in the incidence rates of ureteral strictures was found between the two groups (P = 0.157). There were 13 (50.0%) and 10 (34.5%) cases of ureteral stricture in the stent (n = 26) and control (n = 29) groups, respectively, six months after the end of the radiotherapy. The incidence rates of ureter stricture in the two groups were not significantly different (P = 0.244). Moreover, there were 21 units (40.4%) and 15 units (25.9%) ureteral strictures in the stent and control groups, respectively. No significant difference in the incidence rates of ureteral strictures was found between the two groups (P = 0.105). Complications related to stent placement such as urinary tract infections and bladder irritation were statistically significant (P = 0.006 and P = 0.036) between the two groups; while the other complications were not significantly different (P = 0.070, P = 0.092 and P = 0.586). CONCLUSIONS: Ureteral stents may not reduce the incidence of ureteral stricture after radiotherapy in patients with cervical cancer. The stent needs to be replaced regularly, and the complications related to stent placement may occur at any time. Thus, preoperative stent placement should be cautious for the clinical management of cervical cancer patients treated with postoperative radiotherapy.
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Ureter , Obstrução Ureteral , Neoplasias do Colo do Útero , Constrição Patológica/complicações , Constrição Patológica/etiologia , Feminino , Humanos , Incidência , Estudos Retrospectivos , Stents/efeitos adversos , Ureter/cirurgia , Obstrução Ureteral/epidemiologia , Obstrução Ureteral/etiologia , Obstrução Ureteral/cirurgia , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgiaRESUMO
Bladder cancer is one of the most common malignant tumors in the urinary system with high mortality and morbidity. Evidence revealed that bergenin could affect the development of cancer. Here, we aimed to investigate the effect of bergenin on bladder cancer progression and its mechanism. The effect of bergenin on cell function was first detected, followed by assessing the changes of the epithelial-mesenchymal transition (EMT) in bergenin-treated cells. The effect of bergenin on peroxisome proliferator-activated receptor γ (PPARγ)/phosphatase and tensin homolog (PTEN)/Akt signal pathway was measured by Western blotting, followed by the rescue experiments. The results showed that bergenin treatment significantly decreased cell viability and increased G1 phase arrest, accompanied by reduced expression of Ki67, cycling D1, and cycling B1 in bladder cancer cells. Apoptosis was induced by bergenin in bladder cancer cells, as evidenced by increased Bax and cleaved caspase 3 protein levels and decreased Bcl-2 level in bergenin-treated cells. Meanwhile, the inhibition of the invasion, migration, and EMT was also observed in bergenin-treated cells. Mechanism studies showed that bergenin treatment could activate PPARγ/PTEN/Akt signal pathway, as evidence by the increased nucleus PPARγ and phosphatase and tensin homolog (PTEN) expression and decreased Akt expression. Moreover, PPARγ inhibitor administration inverted the effects of bergenin on bladder cancer cell function, including the proliferation, apoptosis, invasion, and migration in bladder cancer cells. Our findings revealed that bergenin could inhibit bladder cancer progression via activating the PPARγ/PTEN/Akt signal pathway, indicating that bergenin may be a potential therapeutic medicine for bladder cancer treatment.
Assuntos
Benzopiranos/farmacologia , PPAR gama/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Bexiga Urinária/metabolismo , Benzopiranos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Progressão da Doença , Humanos , Transdução de Sinais/fisiologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologiaRESUMO
Retinopathy of prematurity is a major cause of childhood blindness worldwide. Hence, exploring the proper treatment methods is a must in tacking this disease. qRT-PCR and western blot were used to detect the expression of genes and proteins, respectively. The proliferation of human retinal vascular endothelial cells (HRECs) was ensured by MTT assay. The luciferase activity was measured through luciferase assay. The inverted phase-contrast light microscope was used to observe the formation of a vascular tube. In the present study, our data demonstrated that circPDE4B was downregulated, while hypoxia-inducible factor-1α (HIF-1α) and VEGFA were upregulated in the retinopathy of prematurity model in vitro and in vivo. CircPDE4B increasing remarkably inhibited the expression of HIF-1α and VEGFA in hypoxia-induced HRECs and subsequent repressed cell proliferation and pathological angiogenesis. We further found that miR-181c suppressed the expression of von Hippel-Lindau (VHL), while circPDE4B could promote VHL expression via binding to miR-181c. Finally, our results revealed that circPDE4B inhibited the expression of VEGFA and pathological angiogenesis via facilitating VHL-mediated ubiquitin degradation of HIF-1α. In conclusion, circPDE4B suppressed the expression of VEGFA and pathological angiogenesis via promoting VHL-mediated ubiquitin degradation of HIF-1α through binding to miR-181c. Our study indicated that circPDE4B might be an effective therapeutic target of retinopathy of prematurity.
Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/antagonistas & inibidores , RNA Circular/genética , Doenças Retinianas/prevenção & controle , Neovascularização Retiniana/prevenção & controle , Animais , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Oxigênio/toxicidade , Retina/metabolismo , Retina/patologia , Doenças Retinianas/etiologia , Doenças Retinianas/metabolismo , Doenças Retinianas/patologia , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismoRESUMO
1,2,4-Benzenetriol (BT) is one of the phenolic metabolites of benzene, a general occupational hazard and ubiquitous environmental air pollutant with leukemogenic potential in humans. Previous studies have revealed that the benzene metabolites phenol and hydroquinone can inhibit hemin-induced erythroid differentiation in K562 cells. We investigated the roles of DNA methylation and histone acetylation in BT-inhibited erythroid differentiation in K562 cells. When K562 cells were treated with 0, 5, 10, 15 or 20 µM BT for 72 h, hemin-induced hemoglobin synthesis decreased in a concentration-dependent manner. Both 5-aza-2'-deoxycytidine (5-aza-CdR, DNA methyltransferase inhibitor) and trichostatin A (TSA, histone deacetylases inhibitor) could prevent 20 µM BT from inhibiting hemin-induced hemoglobin synthesis and the mRNA expression of erythroid genes. Exposure to BT changed DNA methylation levels at several CpG sites of erythroid-specific genes, as well as the acetylation of histone H3 and H4, chromatin occupancy of GATA-1 and recruitment of RNA polymerase II at α-globin and ß-globin gene clusters after hemin induction. These results demonstrated that BT could inhibit hemin-induced erythroid differentiation, where DNA methylation and histone acetylation also played important roles by down-regulating erythroid-specific genes. This partly explained the mechanisms of benzene hematotoxicity.
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Benzeno/toxicidade , Diferenciação Celular/efeitos dos fármacos , Metilação de DNA , Histonas/química , Acetilação , Azacitidina/farmacologia , Fator de Transcrição GATA1 , Globinas/genética , Hemina/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Humanos , Hidroquinonas , Ácidos Hidroxâmicos/farmacologia , Células K562 , RNA Polimerase IIRESUMO
BACKGROUND: Studies have shown that endothelial-to-mesenchymal transition (EndMT) could contribute to the progression of diabetic nephropathy, diabetic renal fibrosis, and cardiac fibrosis. The aim of this study was to investigate the influence of high glucose and related mechanism of MAPK inhibitor or specific antioxidant on the EndMT. METHODS: In vitro human umbilical vein endothelial cells (HUVEC) were cultured with 11mM, 30mM, 60mM and 120mM glucose for 0, 24, 48, 72 and 168h. Endothelial cell morphology was observed with microscope, and RT-PCR was used to detect mRNA expression of endothelial markers VE-cadherin and CD31, mesenchymal markers α-SMA and collagen I, and transforming growth factor TGF-ß1. Immunofluorescence staining was performed to detect the expression of CD31 and α-SMA. The concentration of TGF-ß1 in the supernatant was detected by ELISA. ERK1/2 phosphorylation level was detected by Western blot analysis. RESULTS: High glucose induced EndMT and increased the TGF-ß1 level in HUVEC cells. Cells in high glucose for 7 days showed a significant decrease in mRNA expression of CD31 and VE-cadherin, and a significant increase in that of α-SMA and collagen I, while lost CD31 staining and acquired α-SMA staining. ERK signaling pathway blocker PD98059 significantly attenuated the high glucose-induced increase in the ERK1/2 phosphorylation level. PD98059 and NAC both inhibited high glucose-induced TGF-ß1 expression and attenuated EndMT marker protein synthesis. CONCLUSION: High glucose could induce HUVEC cells to undergo EndMT. NAC and ERK signaling pathway may play important role in the regulation of the TGF-ß1 biosynthesis during high glucose-induced EndMT.
Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Glucose/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Acetilcisteína/farmacologia , Actinas/genética , Actinas/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Caderinas/genética , Caderinas/metabolismo , Células Cultivadas , Flavonoides/farmacologia , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismoRESUMO
2'-O-methylation is present within various cellular RNAs and is essential to RNA biogenesis and functionality. Several methods have been developed for the identification and localization of 2'-O-methylated sites in RNAs; however, the detection of RNA modifications, especially in low-abundance RNAs and small non-coding RNAs with a 2'-O-methylation at the 3'-end, remains a difficult task. Here, we introduce a new method to detect 2'-O-methylated sites in diverse RNA species, referred to as RTL-P [Reverse Transcription at Low deoxy-ribonucleoside triphosphate (dNTP) concentrations followed by polymerase chain reaction (PCR)] that demonstrates precise mapping and superior sensitivity compared with previous techniques. The main procedures of RTL-P include a site-specific primer extension by reverse transcriptase at a low dNTP concentration and a semi-quantitative PCR amplification step. No radiolabeled or fluorescent primers are required. By designing specific RT primers, we used RTL-P to detect both previously identified and novel 2'-O-methylated sites in human and yeast ribosomal RNAs (rRNAs), as well as mouse piwi-interacting RNAs (piRNAs). These results demonstrate the powerful application of RTL-P for the systematic analysis of fully or partially methylated residues in diverse RNA species, including low-abundance RNAs or small non-coding RNAs such as piRNAs and microRNAs (miRNAs).
Assuntos
RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Animais , Células HEK293 , Humanos , Metilação , Camundongos , Camundongos Endogâmicos C57BL , RNA/química , RNA Ribossômico/metabolismo , Pequeno RNA não Traduzido/química , Pequeno RNA não Traduzido/metabolismo , Ribonucleotídeos/química , Ribonucleotídeos/metabolismo , Schizosaccharomyces/genéticaRESUMO
Benzene-induced erythropoietic depression has been proposed to be due to the production of toxic metabolites. Presently, the cytotoxicities of benzene metabolites, including phenol, catechol, hydroquinone, and 1,2,4-benzenetriol, to erythroid progenitor-like K562 cells were investigated. After exposure to these metabolites, K562 cells showed significant inhibition of viability and apoptotic characteristics. Each metabolite caused a significant increase in activities of caspase-3, -8, and -9, and pretreatment with caspase-3, -8, and -9 inhibitors significantly inhibited benzene metabolites-induced phosphatidylserine exposure. These metabolites also elevated expression of Fas and FasL on the cell surface. After exposure to benzene metabolites, K562 cells showed an increase in reactive oxygen species level, and pretreatment with N-acetyl-l-cysteine significantly protected against the cytotoxicity of each metabolite. Interestingly, the control K562 cells and the phenol-exposed cells aggregated together, but the cells exposed to other metabolites were scattered. Further analysis showed that hydroquione, catechol, and 1,2,4-benzenetriol induced a decrease in the cell surface sialic acid levels and an increase in the cell surface sialidase activity, but phenol did not cause any changes in sialic acid levels and sialidase activity. Consistently, an increase in expression level of sialidase Neu3 mRNA and a decrease in mRNA level of sialyltransferase ST3GAL3 gene were detected in hydroquione-, catechol-, or 1,2,4-benzenetriol-treated cells, but no change in mRNA levels of two genes were found in phenol-treated cells. In conclusion, these benzene metabolites could induce apoptosis of K562 cells mainly through caspase-8-dependent pathway and ROS production, and sialic acid metabolism might play a role in the apoptotic process.
Assuntos
Derivados de Benzeno/toxicidade , Caspases/metabolismo , Ácidos Siálicos/metabolismo , Apoptose , Catecóis/toxicidade , Membrana Celular/metabolismo , Humanos , Hidroquinonas/toxicidade , Células K562 , Fenol/toxicidade , Espécies Reativas de Oxigênio/metabolismoRESUMO
Objective: To improve the understanding, diagnosis and treatment of bladder large cell neuroendocrine carcinoma (LCNEC). Methods: A clinical case of bladder LCNEC admitted to our hospital was reported. The epidemiology, prognosis, diagnosis and treatment methods of large cell neuroendocrine carcinoma were reviewed. The diagnosis and treatment status and prognosis were discussed based on the literature. Results: The female patient was admitted to hospital for "more than 4 years after TURBT and intermittent hematuria for more than 2 years". She was diagnosed as recurrent bladder cancer and underwent "radical cystotomy + hysterectomy". The postoperative pathological findings were high-grade urothelial carcinoma of the bladder neck and large cell neuroendocrine carcinoma of the bladder. The patient recovered well after surgery, but refused radiotherapy and chemotherapy and is still under close follow-up. Conclusion: Bladder LCNEC is clinically rare, has unique pathological features, is more aggressive than traditional urothelial carcinoma, and has a poor prognosis. Surgery, chemotherapy and radiotherapy should be combined with multi-mode treatment.
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Background: Benign prostatic hyperplasia (BPH) is a common disease among older men characterized by non-malignant proliferation of epithelial cells and inflammation. Nitric oxide synthase traffic inducer (NOSTRIN) is a pleiotropic regulator of endothelial cell function and signaling and exerts anti-inflammatory, anti-proliferation, and modulating nuclear factor-kappa B (NF-κB) signaling effects. Its expression and function in BPH tissues and prostate epithelial cells are unknown. The study aims to investigate the expression and functions of NOSTRIN in BPH, and its possible molecular mechanism. Methods: The BPH model was constructed in male Institute of Cancer Research (ICR) mice using 5 mg/kg/day testosterone propionate (TP) for 30 days, and the model was evaluated by detecting prostate index, prostate epithelial thickness, and prostate-specific antigen (PSA) expression. Dihydrotestosterone (DHT, 10 nM)-induced in vitro model of human prostate epithelial cells (RWPE-1) was established. We generated lentivirus-harboring human NOSTRIN. The mRNA expression was detected by real-time quantitative polymerase chain reaction (PCR) assay; the protein expression or localization was detected by western blot assay, immunohistochemistry, or immunofluorescence staining. Cell proliferation was assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and 5-ethynyl-2'-deoxyuridine (EdU) staining. Reactive oxygen species (ROS) production was observed by dihydroethidium staining. Nitric oxide (NO) and malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity were detected using commercial kits. Enzyme-linked immunosorbent assay (ELISA) was used to determine levels of interleukin 1 beta (IL1B), interleukin 6 (IL6), interferon gamma (IFNG), and tumor necrosis factor (TNF). Results: NOSTRIN expression was significantly inhibited in the TP-induced ICR mouse BPH model and DHT-induced model of RWPE-1 proliferation. Protein expression of the BPH-related and proliferation markers PSA and proliferating cell nuclear antigen (PCNA) was suppressed in NOSTRIN-overexpressing RWPE-1 cells exposed to DHT. NOSTRIN overexpression notably inhibited the RWPE-1 cell proliferation in vitro, as evidenced by MTT and EdU staining. NOSTRIN overexpression significantly decreased the expression of cell cycle-related proteins cyclin dependent kinase 4 (CDK4) and cyclin D1 (CCND1) in vitro. The production of ROS, NO, and lipid peroxidation products MDA was inhibited by NOSTRIN overexpression in vitro, while the SOD activity was increased. NOSTRIN overexpression reduced the mRNA expression of inflammatory mediator nitric oxide synthase 2 (NOS2) and inhibited the mRNA expression and secretion of pro-inflammatory cytokines IL1B, IL6, IFNG, and TNF in vitro. The mechanistic studies revealed an increased phosphorylation of NF-κB p65 in vivo and in vitro. Remarkably, NOSTRIN overexpression notably inhibited the protein expression of phospho-NF-κB p65 in vitro. Conclusions: NOSTRIN is involved in BPH by inhibiting proliferation, oxidative stress, and inflammation in prostate epithelial cells. These functions may act through the inhibition of NF-κB signaling.
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Lesions on the DNA template can impact transcription via distinct regulatory pathways. Ionizing radiation (IR) as the mainstay modality for many malignancies elicits most of the cytotoxicity by inducing a variety of DNA damages in the genome. How the IR treatment alters the transcription cycle and whether it contributes to the development of radioresistance remain poorly understood. Here, we report an increase in the paused RNA polymerase II (RNAPII), as indicated by the phosphorylation at serine 5 residue of its C-terminal domain, in recurrent nasopharyngeal carcinoma (NPC) patient samples after IR treatment and cultured NPC cells developing IR resistance. Reducing the pool of paused RNAPII by either inhibiting TFIIH-associated CDK7 or stimulating the positive transcription elongation factor b, a CDK9-CycT1 heterodimer, attenuates IR resistance of NPC cells. Interestingly, the poly(ADP-ribosyl)ation of CycT1, which disrupts its phase separation, is elevated in the IR-resistant cells. Mutation of the major poly(ADP-ribosyl)ation sites of CycT1 decreases RNAPII pausing and restores IR sensitivity. Genome-wide chromatin immunoprecipitation followed by sequencing analyses reveal that several genes involved in radiation response and cell cycle control are subject to the regulation imposed by the paused RNAPII. Particularly, we identify the NIMA-related kinase NEK7 under such regulation as a new radioresistance factor, whose downregulation results in the increased chromosome instability, enabling the development of IR resistance. Overall, our results highlight a novel link between the alteration in the transcription cycle and the acquisition of IR resistance, opening up new opportunities to increase the efficacy of radiotherapy and thwart radioresistance in NPC.
Assuntos
Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/patologia , Linhagem Celular Tumoral , Radiação Ionizante , DNARESUMO
Catechol is widely used in pharmaceutical and chemical industries. Catechol is also one of phenolic metabolites of benzene in vivo. Our previous study showed that catechol improved erythroid differentiation potency of K562 cells, which was associated with decreased DNA methylation in erythroid specific genes. Catechol is a substrate for the catechol-O-methyltransferase (COMT)-mediated methylation. In the present study, the role of COMT in catechol-enhanced erythroid differentiation of K562 cells was investigated. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation and induced mRNA expression of erythroid specific genes in K562 cells. Treatment with catechol caused a time- and concentration-dependent increase in guaiacol concentration in the medium of cultured K562 cells. When COMT expression was knocked down by COMT shRNA expression in K562 cells, the production of guaiacol significantly reduced, and the sensitivity of K562 cells to cytotoxicity of catechol significantly increased. Knockdown of COMT expression by COMT shRNA expression also eliminated catechol-enhanced erythroid differentiation of K562 cells. In addition, the pre-treatment with methyl donor S-adenosyl-L-methionine or its demethylated product S-adenosyl-L-homocysteine induced a significant increase in hemin-induced Hb synthesis in K562 cells and the mRNA expression of erythroid specific genes. These findings indicated that O-methylation catalyzed by COMT acted as detoxication of catechol and involved in catechol-enhanced erythroid differentiation of K562 cells, and the production of S-adenosyl-L-homocysteine partly explained catechol-enhanced erythroid differentiation.
Assuntos
Catecol O-Metiltransferase/metabolismo , Catecóis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Catecol O-Metiltransferase/genética , Sobrevivência Celular , Células Eritroides/citologia , Células Eritroides/efeitos dos fármacos , Hemina/metabolismo , Hemoglobinas/metabolismo , Humanos , Células K562 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , S-Adenosil-Homocisteína/metabolismoRESUMO
The temperature-concentration behavior of physical gel by atactic poly(methyl methacrylate) (aPMMA) in poly(ethylene glycol) oligomer (PEG400) was investigated. A liquid-liquid demixing interferes with a glass transition during cooling. The combination of demixing and T g leads to the formation of amorphous gels at low temperature. We suggest that the gelation of aPMMA/PEG400 is a glassy gel, in which short-range attractive depletion interaction in the polymer/oligomer system was the driving force at molecular level.
Assuntos
Polietilenoglicóis/química , Polimetil Metacrilato/química , Temperatura , Géis , Reologia , Soluções , TermodinâmicaRESUMO
Objective: Insulin resistance (IR) has a bearing on blood pressure (BP). Nevertheless, research on the relationships between surrogates for IR and BP is limited. In this study, we investigate the associations of these novel IR indices with BP in new-onset hypertension (HTN) and elevated BP individuals. Methods: An overall sample of 55,381 adult subjects was included in Hebei General Hospital. BP and other clinical indicators were measured. Triglyceride glucose (TyG) index, TyG-waist circumference (TyG-WC), TyG-body mass index (TyG-BMI), TyG-waist to height ratio (TyG-WHtR), triglyceride-to-high-density lipoprotein-cholesterol ratio (TG/HDL-C) and metabolic score for IR (METS-IR) were collected as dependable surrogates for IR. Examinees were categorized into four groups based on BP levels. Those involved were classified as quartiles according to the levels of six surrogate IR indices. Logistic regression analysis was adopted to evaluate the impact of substitute IR indicators on BP. The receiver operating characteristic curve (ROC) analysis was performed to explore the predictive ability of the parameters on BP. Results: The incidence of elevated BP, stage 1 HTN and stage 2 HTN was 7.86%, 24.05% and 23.76%, respectively. As the levels of six substitute IR indices rose, so did the BP. In the logistic regression analysis, after full adjustment, all alternative IR indicators were independently related to both stage 1 HTN and stage 2 HTN. Except for TG/HDL-C, other substitute IR indices were strongly associated with elevated BP. ROC curves analysis suggested TyG-WC and TyG-WHtR outperformed other indicators with higher odd ratios and area under the curve (AUC) in all the participants. Conclusion: Increased substitute IR indices were significantly associated with elevated BP in new-onset HTN and elevated BP individuals. TyG-WC and TyG-WHtR could better predict elevated BP, stage 1 HTN and stage 2 HTN.
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We reported an 85-year-old patient with malignant glomus tumor (GT) of the prostate. He presented with urinary frequency for more than 2 years and gross hematuria for 7 days. Computed tomography scan showed that the prostate was markedly irregularly enlarged, and the boundary between the prostate and the posterior wall of the bladder was unclear. Bilateral kidneys and ureters were dilated. Biochemical examinations showed that the serum potassium was 7.24 mmol/L and the serum creatinine was 974.6 µmol/L. Transurethral diagnostic resection was performed after restoring homeostasis through several times of bedside blood filtration. The pathological diagnosis was malignant GT. The patient's renal function recovered after bilateral nephrostomy, and he refused further treatment and was out of contact after 9 months. We summarize the clinical and histopathological features of malignant GT of the prostate in order to improve the early recognition of the disease by clinicians.
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Among the most common cancers, hepatocellular carcinoma (HCC) has a high rate of tumor recurrence, tumor dormancy, and drug resistance after initial successful chemotherapy or radiotherapy. A small subset of cancer cells, cancer stem cells (CSCs), exhibit stem cell characteristics and are present in various cancers, including HCC. The dysregulation of microRNAs (miRNAs) often accompanies the occurrence and development of HCC. miRNAs can influence tumorigenesis, progression, recurrence, and drug resistance by regulating CSCs properties, which supports their clinical utility in managing and treating HCC. This review summarizes the regulatory effects of miRNAs on CSCs in HCC with a special focus on their impact on HCC recurrence.
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Background: The association between free triiodothyronine/free thyroxine (FT3/FT4) and non-alcoholic fatty liver disease (NAFLD) in euthyroid subjects is unclear. In addition, few studies have explored whether VAI mediates the association between FT3/FT4 ratio and NAFLD in the euthyroid population. We aimed to analyze the mediating effect of VAI on the FT3/FT4 ratio and NAFLD risk in the euthyroid population. Methods: This cross-sectional study included 7 946 annual health examinees from the Health Examination Center, Hebei General Hospital, from January to December 2020. The basic information and biochemical parameters, as well as calculated FT3/FT4 ratio and VAI were collected. NAFLD was diagnosed according to abdominal ultrasonography. The fibrosis score for NAFLD positive subjects (NFS) was calculated to reflect the extent of liver fibrosis. The risk of NAFLD was analyzed by quartiles of FT3/FT4 ratio (Q1-Q4 quartiles) and VAI (V1-V4 quartiles), respectively. Pearson correlation analysis was performed to investigate the correlation between FT3/FT4 ratio and VAI. Multivariate logistic regression analysis was applied to analyze the effect of FT3/FT4 ratio and VAI on NAFLD and NFS status. Bootstrap was conducted to explore whether VAI mediated the association between FT3/FT4 ratio and NAFLD. Results: Of the 7 946 participants, 2 810 (35.36%) had NAFLD and 5 136 (64.64%) did not. Pearson correlation analysis indicated that FT3/FT4 ratio was positively associated with VAI (P<0.05). Multivariate logistic regression analysis indicated that compared to the Q1 group, the risk of NAFLD significantly increased in Q3 group [OR=1.255, 95%CI (1.011, 1.559)] and Q4 group [OR=1.553, 95%CI (1.252, 1.926)](P<0.05). Compared to the V1 group, the risk of NAFLD notably increased in V2 group [OR=1.584, 95%CI (1.205, 2.083)], V3 group [OR=2.386, 95%CI (1.778, 3.202)] and V4 group [OR=4.104, 95%CI (2.835, 5.939)] (P<0.01). There was no relevance between FT3/FT4 ratio, VAI and NFS status. Mediating effect analysis showed that FT3/FT4 ratio significantly directly influenced NAFLD prevalence [ß=3.7029, 95%CI (2.9583, 4.4474)], and VAI partly mediated the indirect effect of the FT3/FT4 ratio on NAFLD prevalence [ß=2.7649, 95%CI (2.2347, 3.3466)], and the mediating effect accounted for 42.75% of the total effects. Conclusion: Both FT3/FT4 ratio and VAI were predictors of NAFLD, and VAI partly mediated the indirect effect of the FT3/FT4 ratio on NAFLD prevalence in the euthyroid population.
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Hepatopatia Gordurosa não Alcoólica , Tri-Iodotironina , Adiposidade , Estudos Transversais , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Fatores de Risco , TiroxinaRESUMO
INTRODUCTION: Cyclin-dependent kinase 12 (CDK12) belongs to the CDK family of serine/threonine protein kinases and is associated with cyclin K to exert its biological functions, including regulating gene transcription, mRNA processing, and translation. Increasing evidences demonstrate the importance of CDK12 in various human cancers, illustrating its potential as both biomarker and therapeutic target. In addition, CDK12 is also a promising target for the treatment of myotonic dystrophy type 1. Efforts have been taken to discover small molecule inhibitors to validate this important therapeutic target. AREAS COVERED: This review covers the patented CDK12 inhibitors from 2016 to present, as well as these from peer-reviewed literature. It provides the reader an update of the discovery strategies, chemical structures, and molecular profiling of all available CDK12 inhibitors. EXPERT OPINION: CDK12 inhibitors with various mechanism of actions have been discovered, and it is a great set of tools to evaluate the therapeutic potential of CDK12 in different disease models. CDK12 inhibitors have shown promising results in myotonic dystrophy type 1 mouse model and several preclinical cancer models either as single agent or combination with other anti-cancer agents. Its therapeutic value awaits more rigorous preclinical testing and further clinical investigation.
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Distrofia Miotônica , Neoplasias , Animais , Humanos , Camundongos , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/genética , Ciclinas/metabolismo , Ciclinas/uso terapêutico , Distrofia Miotônica/tratamento farmacológico , Neoplasias/tratamento farmacológico , Neoplasias/genética , Patentes como Assunto , RNA Mensageiro/uso terapêutico , Serina , Treonina/uso terapêutico , Inibidores de Proteínas Quinases/farmacologiaRESUMO
BACKGROUND: Hydroquinone (HQ) is a phenolic metabolite of benzene with a potential risk for hematological disorders and hematotoxicity in humans. In the present study, an integrative analysis of microRNA (miRNA) and mRNA expressions was performed to identify potential pathways and miRNA-mRNA network associated with benzene metabolite hydroquinone-induced hematotoxicity. METHODS: K562 cells were treated with 40 µM HQ for 72 h, mRNA and miRNA expression changes were examined using transcriptomic profiles and miRNA microarray, and then bioinformatics analysis was performed. RESULTS: Out of all the differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) induced by HQ, 1482 DEGs and 10 DEMs were up-regulated, and 1594 DEGs and 42 DEMs were down-regulated. HQ-induced DEGs were involved in oxidative stress, apoptosis, DNA methylation, histone acetylation and cellular response to leukemia inhibitory factor GO terms, as well as metabolic, Wnt/ß-catenin, NF-κB, and leukemia-related pathways. The regulatory network of mRNAs and miRNAs includes 23 miRNAs, 1108 target genes, and 2304 potential miRNAs-mRNAs pairs. MiR-1246 and miR-224 had the potential to be major regulators in HQ-exposed K562 cells based on the miRNAs-mRNAs network. CONCLUSIONS: This study reinforces the use of in vitro model of HQ exposure and bioinformatic approaches to advance our knowledge on molecular mechanisms of benzene hematotoxicity at the RNA level.