RESUMO
BACKGROUND: At present, liver transplantation (LT) is one of the best treatments for hepatocellular carcinoma (HCC). Accurately predicting the survival status after LT can significantly improve the survival rate after LT, and ensure the best way to make rational use of liver organs. AIM: To develop a model for predicting prognosis after LT in patients with HCC. METHODS: Clinical data and follow-up information of 160 patients with HCC who underwent LT were collected and evaluated. The expression levels of alpha-fetoprotein (AFP), des-gamma-carboxy prothrombin, Golgi protein 73, cytokeratin-18 epitopes M30 and M65 were measured using a fully automated chemiluminescence analyzer. The best cutoff value of biomarkers was determined using the Youden index. Cox regression analysis was used to identify the independent risk factors. A forest model was constructed using the random forest method. We evaluated the accuracy of the nomogram using the area under the curve, using the calibration curve to assess consistency. A decision curve analysis (DCA) was used to evaluate the clinical utility of the nomograms. RESULTS: The total tumor diameter (TTD), vascular invasion (VI), AFP, and cytokeratin-18 epitopes M30 (CK18-M30) were identified as important risk factors for outcome after LT. The nomogram had a higher predictive accuracy than the Milan, University of California, San Francisco, and Hangzhou criteria. The calibration curve analyses indicated a good fit. The survival and recurrence-free survival (RFS) of high-risk groups were significantly lower than those of low- and middle-risk groups (P < 0.001). The DCA shows that the model has better clinical practicability. CONCLUSION: The study developed a predictive nomogram based on TTD, VI, AFP, and CK18-M30 that could accurately predict overall survival and RFS after LT. It can screen for patients with better postoperative prognosis, and improve long-term survival for LT patients.
Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Nomogramas , alfa-Fetoproteínas , Humanos , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/sangue , Masculino , Transplante de Fígado/efeitos adversos , Pessoa de Meia-Idade , Feminino , Fatores de Risco , alfa-Fetoproteínas/análise , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/análise , Prognóstico , Adulto , Estudos Retrospectivos , Idoso , Resultado do Tratamento , Queratina-18/sangue , Queratina-18/análise , Técnicas de Apoio para a DecisãoRESUMO
OBJECTIVE: The presence of intestinal metaplasia (IM) is a risk factor for gastric cancer. However, it is still controversial whether IM itself is precancerous or paracancerous. Here, we aimed to explore the precancerous nature of IM by analysing epigenetic alterations. DESIGN: Genome-wide DNA methylation analysis was conducted by EPIC BeadArray using IM crypts isolated by Alcian blue staining. Chromatin immunoprecipitation sequencing for H3K27ac and single-cell assay for transposase-accessible chromatin by sequencing were conducted using IM mucosa. NOS2 was induced using Tet-on gene expression system in normal cells. RESULTS: IM crypts had a methylation profile unique from non-IM crypts, showing extensive DNA hypermethylation in promoter CpG islands, including those of tumour-suppressor genes. Also, the IM-specific methylation profile, namely epigenetic footprint, was present in a fraction of gastric cancers with a higher frequency than expected, and suggested to be associated with good overall survival. IM organoids had remarkably high NOS2 expression, and NOS2 induction in normal cells led to accelerated induction of aberrant DNA methylation, namely epigenetic instability, by increasing DNA methyltransferase activity. IM mucosa showed dynamic enhancer reprogramming, including the regions involved in higher NOS2 expression. NOS2 had open chromatin in IM cells but not in gastric cells, and IM cells had frequent closed chromatin of tumour-suppressor genes, indicating their methylation-silencing. NOS2 expression in IM-derived organoids was upregulated by interleukin-17A, a cytokine secreted by extracellular bacterial infection. CONCLUSIONS: IM cells were considered to have a precancerous nature potentially with an increased chance of converting into cancer cells, and an accelerated DNA methylation induction due to abnormal NOS2 expression.
Assuntos
Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Metilação de DNA , Neoplasias Gástricas/microbiologia , DNA , Cromatina/metabolismo , Metaplasia/genética , Metaplasia/metabolismo , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Mucosa Gástrica/metabolismo , Helicobacter pylori/genética , Infecções por Helicobacter/complicaçõesRESUMO
BACKGROUND: Autoimmune gastritis (AIG) is a prevalent chronic inflammatory disease with oncogenic potential that causes destruction of parietal cells and severe mucosal atrophy. We aimed to explore the distinctive gene expression profiles, activated signaling pathways, and their underlying mechanisms. METHODS: A comprehensive gene expression analysis was conducted using biopsy specimens from AIG, Helicobacter pylori-associated gastritis (HPG), and non-inflammatory normal stomachs. Gastric cancer cell lines were cultured under acidic (pH 6.5) conditions to evaluate changes in gene expression. RESULTS: Gastric mucosa with AIG had a unique gene expression profile compared with that with HPG and normal mucosa, such as extensively low expression of ATP4A and high expression of GAST and PAPPA2, which are involved in neuroendocrine tumorigenesis. Additionally, the mucosa with AIG and HPG showed the downregulation of stomach-specific genes and upregulation of small intestine-specific genes; however, intestinal trans-differentiation was much more prominent in AIG samples, likely in a CDX-dependent manner. Furthermore, AIG induced ectopic expression of pancreatic digestion-related genes, PNLIP, CEL, CTRB1, and CTRC; and a master regulator gene of the lung, NKX2-1/TTF1 with alveolar fluid secretion-related genes, SFTPB and SFTPC. Mechanistically, acidic conditions led to the downregulation of master regulator and stemness control genes of small intestine, suggesting that increased environmental pH may cause abnormal intestinal differentiation in the stomach. CONCLUSIONS: AIG induces diverse trans-differentiation in the gastric mucosa, characterized by the transactivation of genes specific to the small intestine, pancreas, and lung. Increased environmental pH owing to AIG may cause abnormal differentiation of the gastric mucosa.
Assuntos
Doenças Autoimunes , Gastrite , Infecções por Helicobacter , Helicobacter pylori , Humanos , Doenças Autoimunes/genética , Gastrite/genética , Gastrite/patologia , Mucosa Gástrica/patologia , Pâncreas/patologia , Transdiferenciação CelularRESUMO
PURPOSE: HER2-positive breast cancer has a high chance of achieving pathological complete response when HSD17B4, responsible for peroxisomal ß-oxidation of very long-chain fatty acids (VLCFA) and estradiol, is methylation-silenced. Here, we aimed to identify the underlying molecular mechanism. METHODS: Using a HER2-positive breast cancer cell line, BT-474, control and knock-out (KO) clones were obtained. Metabolic characteristics were analyzed using a Seahorse Flux analyzer. RESULTS: HSD17B4 KO suppressed cellular proliferation, and enhanced sensitivity to lapatinib approximately tenfold. The KO led to accumulation of VLCFA and a decrease of polyunsaturated fatty acids (PUFAs), such as docosahexaenoic acid (DHA) and arachidonic acid. HSD17B4 KO increased Akt phosphorylation, possibly via decreased DHA, and genes involved in oxidative phosphorylation (OxPhos) and electron transport chain (ETC) were upregulated. Increased mitochondrial ATP production in the KO cells was confirmed by extracellular flux analyzer. Increased OxPhos led to severe dependence of the KO cells on pyruvate from glycolysis. Suppression of glycolysis by lapatinib led to severe delayed suppression of OxPhos in KO cells. CONCLUSION: HSD17B4 KO in BT-474 cells caused a decrease of PUFAs, increased Akt phosphorylation, enhanced glucose dependence of OxPhos, and increased sensitivity to inhibition of HER2, upstream of Akt. This mechanism may be applicable to other HER2-positive glucose-dependent breast cancer cells with HSD17B4 silencing.
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Neoplasias da Mama , Humanos , Feminino , Lapatinib/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Metilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Glucose , Linhagem Celular Tumoral , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Proteína Multifuncional do Peroxissomo-2/genética , Proteína Multifuncional do Peroxissomo-2/metabolismoRESUMO
BACKGROUND: Gastric cancer risk can be accurately predicted by measuring the methylation level of a single marker gene in gastric mucosa. However, the mechanism is still uncertain. We hypothesized that the methylation level measured reflects methylation alterations in the entire genome (methylation burden), induced by Helicobacter pylori (H. pylori) infection, and thus cancer risk. METHODS: Gastric mucosa of 15 healthy volunteers without H. pylori infection (G1), 98 people with atrophic gastritis (G2), and 133 patients with gastric cancer (G3) after H. pylori eradication were collected. Methylation burden of an individual was obtained by microarray analysis as an inverse of the correlation coefficient between the methylation levels of 265,552 genomic regions in the person's gastric mucosa and those in an entirely healthy mucosa. RESULTS: The methylation burden significantly increased in the order of G1 (n = 4), G2 (n = 18), and G3 (n = 19) and was well correlated with the methylation level of a single marker gene (r = 0.91 for miR124a-3). The average methylation levels of nine driver genes tended to increase according to the risk levels (P = 0.08 between G2 vs G3) and was also correlated with the methylation level of a single marker gene (r = 0.94). Analysis of more samples (14 G1, 97 G2, and 131 G3 samples) yielded significant increases of the average methylation levels between risk groups. CONCLUSIONS: The methylation level of a single marker gene reflects the methylation burden, which includes driver gene methylation, and thus accurately predicts cancer risk.
Assuntos
Gastrite Atrófica , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Metilação de DNA , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Mucosa Gástrica/metabolismo , Gastrite Atrófica/genética , Fatores de Risco , Infecções por Helicobacter/complicações , Infecções por Helicobacter/genéticaRESUMO
A nickel-catalyzed three-component tandem radical cyclization reaction of aryl bromides with 1,3-enynes and aryl boric acids to construct γ-lactam-substituted allene derivatives has been described. This protocol provides lactam alkyl radicals through the free radical cyclization process, which can be effectively used to participate in the subsequent multicomponent coupling reaction so that 1,3-enynes could directly convert into corresponding poly-substituted allene compounds. In addition, this efficient method enjoys a broad substrate scope and provides a series of 1,5-difunctionalized allenes in a one-pot reaction.
RESUMO
Somatic mutations are accumulated in normal human tissues with aging and exposure to carcinogens. If we can accurately count any passenger mutations in any single DNA molecule, since their quantity is much larger than driver mutations, we can sensitively detect mutation accumulation in polyclonal normal tissues. Duplex sequencing, which tags both DNA strands in one DNA molecule, enables accurate count of such mutations, but requires a very large number of sequencing reads for each single sample of human-genome size. Here, we reduced the genome size to 1/90 using the BamHI restriction enzyme and established a cost-effective pipeline. The enzymatically cleaved and optimal sequencing (EcoSeq) method was able to count somatic mutations in a single DNA molecule with a sensitivity of as low as 3 × 10-8 per base pair (bp), as assessed by measuring artificially prepared mutations. Taking advantages of EcoSeq, we analyzed normal peripheral blood cells of pediatric sarcoma patients who received chemotherapy (n = 10) and those who did not (n = 10). The former had a mutation frequency of 31.2 ± 13.4 × 10-8 per base pair while the latter had 9.0 ± 4.5 × 10-8 per base pair (P < 0.001). The increase in mutation frequency was confirmed by analysis of the same patients before and after chemotherapy, and increased mutation frequencies persisted 46 to 64 mo after chemotherapy, indicating that the mutation accumulation constitutes a risk of secondary leukemia. EcoSeq has the potential to reveal accumulation of somatic mutations and exposure to environmental factors in any DNA samples and will contribute to cancer risk estimation.
Assuntos
Análise Mutacional de DNA , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Taxa de Mutação , Imagem Individual de Molécula , Envelhecimento/genética , Pareamento de Bases , Criança , Análise Mutacional de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mutação , Imagem Individual de Molécula/métodosRESUMO
BACKGROUND: Autoimmune gastritis (AIG) is a chronic inflammatory condition in gastric mucosa and is associated with increased cancer risk, though not as high as that by Helicobacter pylori (H. pylori)-associated gastritis (HPG). Although aberrant DNA methylation is induced by HPG and the level correlates with the risk of gastric cancer, DNA methylation induction by AIG is unknown. METHODS: Gastric mucosa samples from the corpus were collected from 12 people with AIG without H. pylori infection, 10 people with HPG, and eight healthy volunteers. Genome-wide DNA methylation analysis was conducted using Infinium Methylation EPIC array. Gene expression was analyzed by quantitative RT-PCR. RESULTS: The AIG samples had extensive aberrant DNA methylation but presented unique methylation profiles against the HPG samples after correction of leucocyte fractions. Comparison between the AIG and HPG samples showed that AIG induced methylation, but less than HPG, in overall CpG sites and also in promoter CpG islands. Promoter CpG islands of tumor-suppressor genes in the pathway of cell cycle, cell adhesion, p53, and WNT were highly methylated in the AIG samples, but more so in the HPG samples. The expression levels of IL1B and IL8, secreted by macrophage, were significantly lower in the AIG samples than in the HPG samples, suggesting that a difference in inflammatory response affected the degree and patterns of aberrant DNA methylation. CONCLUSIONS: AIG induced aberrant DNA methylation in gastric mucosa. However, the degree of DNA methylation was less than that by HPG, which reflected carcinogenic risk.
Assuntos
Gastrite , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Carcinógenos , Ilhas de CpG/genética , Metilação de DNA , Mucosa Gástrica/metabolismo , Gastrite/complicações , Gastrite/genética , Infecções por Helicobacter/complicações , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Humanos , Neoplasias Gástricas/metabolismoRESUMO
BACKGROUND: Prediction of tissue origin of esophagogastric junction (EGJ) adenocarcinomas can be important for therapeutic decision, but no molecular marker is available. Here, we aimed to develop such a marker taking advantage of tissue-specific profiles of DNA methylation. METHODS: DNA methylation profiles of gastric adenocarcinomas (GACs) were obtained by an Infinium HumanMethylation450 BeadChip array, and those of esophageal adenocarcinoma (EACs) were obtained from the TCGA database. DNA from formalin-fixed paraffin-embedded (FFPE) samples was analyzed by bisulfite pyrosequencing. RESULTS: In the screening set, 51 of 145,841 CpG sites in CpG islands were methylated at significantly higher levels in 30 GACs compared to those in 30 EACs. Among them, SLC46A3 and cg09177106 were unmethylated in all the 30 EACs. Predictive powers of these two markers were successfully confirmed in an independent validation set (18 GACs and 18 EACs) (SLC46A3, sensitivity = 77.8%, specificity = 100%; cg09177106, sensitivity = 83.3%, specificity = 94.4%), and could be applied to FFPE samples (37 GACs and 18 EACs) (SLC46A3, P = 0.0001; cg09177106, P = 0.0028). On the other hand, EAC-specific markers informative in the FFPE samples could not be isolated. Using these GAC-specific markers, nine of 46 (19.6%) TCGA EGJ adenocarcinomas were predicted to be GACs. CONCLUSIONS: Two GAC-specific markers, SLC46A3 and cg09177106, had a high specificity for identifying the tissue origin of EGJ adenocarcinoma.
Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Neoplasias Gástricas , Adenocarcinoma/genética , Adenocarcinoma/patologia , Metilação de DNA , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologiaRESUMO
OBJECTIVE: To investigate the effect of arsenic disulfide (AS2S2) combined with itraconazole on the proliferation, apoptosis and hedgehog pathway of diffuse large B-cell lymphoma (DLBCL) cells. METHODS: The human DLBCL cell OCI-LY3 was treated with different concentrations of AS2S2 and itraconazole. Cell proliferation inhibition was detected by CCK-8, cell apoptosis rate was determined by flow cytometry. The expression levels of BCL-2, BAX, SMO and GLi1 were detected by Western blot. RESULTS: The DLBCL cell viability was decreased significantly at 24, 48 or 72 h as cultured with itraconazole. Along with the increasing of itraconazole concentration, the DLBCL cell viability was significantly reduced as compared with that in control group, and the results showed statistically significant(r=-0.690ï¼r=-0.639, r=-0.833, r=-0.808, r=-0.578). The inhibitory and apoptosis rates of the cells were significantly increased as compared with those of the single drug-treated group after treated by the combination of itraconazole and AS2S2(P<0.05). The protein levels of SMO and Glil were significantly down-regulated after treated by arsenic disulfide and itraconazole alone(P<0.01). The protein expression levels of SMO and Glil was down-regulated in the combined-treatment group(P<0.01). CONCLUSION: Itraconazole can inhibit proliferation of DLBCL cells in a concentration-and time-dependent manner. In addition, the combination of AS2S2 and itraconazole show a synergistic effects, which may be related with the down-regulated protein expression of SMO and Glil of Hedgehog signaling pathway.
Assuntos
Proteínas Hedgehog , Linfoma Difuso de Grandes Células B , Apoptose , Arsenicais , Humanos , Itraconazol/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , SulfetosRESUMO
HER2-positive breast cancers that achieve pathological complete response (pCR) after HER2-directed therapy consistently have good survival. We previously identified HSD17B4 methylation as a marker for pCR by methylation screening. Here, we aimed to identify a new marker by conducting a multi-omics analysis of materials prepared by laser capture microdissection, and adding 71 new samples. In the screening set (n = 36), mutations, methylation, and expression were analyzed by targeted sequencing, Infinium 450 K, and expression microarray, respectively, and 15 genes were identified as differentially expressed and eight genomic regions as differentially methylated between cancer samples with and without pCR. In a validation set (n = 47), one gene showed differential expression, and one region had differential methylation. Further, in the re-validation set (n = 55), all new samples, only HSD17B4 methylation was significantly different. The HSD17B4 methylation was at the transcriptional start site of its major variant, and was associated with its silencing. HSD17B4 was highly expressed in the vast majority of human cancers, and its methylation was present only in breast cancers and one lymphoblastic leukemia cell line. A combination of estrogen receptor-negative status and HSD17B4 methylation showed a positive predictive value of 80.0%. During HER2-directed neoadjuvant therapy, HSD17B4 methylation was the most reliable marker to monitor response to the therapy. These results showed that HSD17B4 methylation is a candidate predictive and response marker of HER2-positive breast cancer to HER2-directed therapy.
Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Neoplasias da Mama/genética , Proteína Multifuncional do Peroxissomo-2/genética , Receptor ErbB-2/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Metilação de DNA , DNA de Neoplasias/genética , Feminino , Inativação Gênica , Humanos , Pessoa de Meia-Idade , Receptor ErbB-2/antagonistas & inibidores , Transcriptoma , Resultado do TratamentoRESUMO
End-stage renal disease (ESRD) patients on dialysis therapy have a higher incidence of renal cell carcinomas (RCCs), which consist of 2 major histopathological types: clear-cell RCCs (ESRD-ccRCCs) and acquired cystic disease (ACD)-associated RCCs. However, their genetic and epigenetic alterations are still poorly understood. Here, we investigated somatic mutations, copy number alterations (CNAs), and DNA methylation profiles in 9 ESRD-ccRCCs and 7 ACD-associated RCCs to identify their molecular alterations and cellular origins. Targeted sequencing of 409 cancer-related genes, including VHL, PBRM1, SETD2, BAP1, KDM5C, MET, KMT2C (MLL3), and TP53, showed ESRD-ccRCCs harbored frequent VHL mutations, while ACD-associated RCCs did not. CNA analysis showed that ESRD-ccRCCs had a frequent loss of chromosome 3p while ACD-associated RCCs had a gain of chromosome 16. Beadarray methylation analysis showed that ESRD-ccRCCs had methylation profiles similar to those of sporadic ccRCCs, while ACD-associated RCCs had profiles similar to those of papillary RCCs. Expression analysis of genes whose expression levels are characteristic to individual segments of a nephron showed that ESRD-ccRCCs and ACD-associated RCCs had high expression of proximal tubule cell marker genes, while chromophobe RCCs had high expression of distal tubule cell/collecting duct cell marker genes. In conclusion, ESRD-ccRCCs and ACD-associated RCCs had mutation and methylation profiles similar to those of sporadic ccRCCs and papillary RCCs, respectively, and these 2 histopathological types of RCCs were indicated to have originated from proximal tubule cells of the nephron.
Assuntos
Epigênese Genética , Predisposição Genética para Doença , Falência Renal Crônica/complicações , Falência Renal Crônica/genética , Neoplasias Renais/etiologia , Neoplasias Renais/patologia , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Adulto , Idoso , Carcinoma de Células Renais/etiologia , Carcinoma de Células Renais/patologia , Variações do Número de Cópias de DNA , Epigenoma , Feminino , Perfilação da Expressão Gênica , Genótipo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação , TranscriptomaRESUMO
For total knee replacement (TKR) patients, rehabilitation after the surgery is key toregaining mobility. This study proposes a sensor-based system for effectively monitoringrehabilitation progress after TKR. The system comprises a hardware module consisting of thetriaxial accelerometer and gyroscope, a microcontroller, and a Bluetooth module, and a softwareapp for monitoring the motion of the knee joint. Three indices, namely the number of swings, themaximum knee flexion angle, and the duration of practice each time, were used as metrics tomeasure the knee rehabilitation progress. The proposed sensor device has advantages such asusability without spatiotemporal constraints and accuracy in monitoring the rehabilitation progress.The performance of the proposed system was compared with the measured range of motion of theCybex isokinetic dynamometer (or Cybex) professional rehabilitation equipment, and the resultsrevealed that the average absolute errors of the measured angles were between 1.65° and 3.27° forthe TKR subjects, depending on the swing speed. Experimental results verified that the proposedsystem is effective and comparable with the professional equipment.
Assuntos
Artroplastia do Joelho/reabilitação , Técnicas Biossensoriais , Articulação do Joelho/fisiologia , Monitorização Fisiológica , Amplitude de Movimento Articular/fisiologia , Recuperação de Função Fisiológica/fisiologia , Acelerometria/instrumentação , Acelerometria/métodos , Actigrafia/instrumentação , Actigrafia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aplicativos Móveis , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Modalidades de Fisioterapia/instrumentação , Rotação , Telemedicina/instrumentação , Telemedicina/métodos , Telemetria/instrumentação , Telemetria/métodos , Resultado do Tratamento , Dispositivos Eletrônicos Vestíveis , Adulto JovemRESUMO
The p53 protein is a tumour suppressor and transcription factor that regulates the expression of target genes involved in numerous stress responses systems. In this study, we designed a screening strategy using DNA damageinduced mouse and human transcriptome data to identify novel downstream targets of p53. Our method selected genes with an induced expression in multiple organs of Xrayirradiated p53 wildtype mice. The expression of inka box actin regulator 2 gene, known as Inka2, was upregulated in 12 organs when p53 expression was induced. Similarly, INKA2 was induced in a p53dependent manner at both the mRNA and protein level in human cells treated with adriamycin. Reporter assays confirmed that p53 directly regulated INKA2 through an intronic binding site. The overexpression of INKA2 produced a slight decrease in cancer cell growth in the colony formation assay. Moreover, the analysis of The Cancer Genome Atlas (TCGA) data revealed a decreased INKA2 expression in tumour samples carrying p53 mutations compared with p53 wildtype samples. In addition, significantly higher levels of DNA methylation were observed in the INKA2 promoter in tumour samples, concordant with the reduced INKA2 expression in tumour tissues. These results demonstrate the potential of INKA2 as a cancer cell growth inhibitor. Furthermore, INKA2 protein interacts with the serine/threonineprotein kinase, p21 (RAC1) activated kinase (PAK)4, which phosphorylates ßcatenin to prevent ubiquitinproteasomal degradation. As ßcatenin was downregulated in a stable INKA2expressing cell line, the findings of this study suggest that INKA2 is a novel, direct downstream target of p53 that potentially decreases cell growth by inhibiting the PAK4ßcatenin pathway.
Assuntos
Perfilação da Expressão Gênica/métodos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias/genética , Proteína Supressora de Tumor p53/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Linhagem Celular Tumoral , Metilação de DNA , Doxorrubicina/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Células HCT116 , Humanos , Camundongos , Mutação , Neoplasias/metabolismo , Fosforilação , Regiões Promotoras Genéticas , Análise de Sequência de RNA/métodos , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , beta Catenina/metabolismoRESUMO
Glucocorticoid (GC)-induced osteoporosis (GIO) is characterized by impaired bone formation, which can be alleviated by tanshinol, an aqueous polyphenol isolated from Salvia miltiorrhiza Bunge. In this study we investigated the molecular mechanisms underlying GC-induced modulation of osteogenesis as well as the possibility of using tanshinol to interfere with GIO. Female SD rats aged 4 months were orally administered distilled water (Con), prednisone (GC, 5 mg·kg-1·d-1), GC plus tanshinol (Tan, 16 mg·kg-1·d-1) or GC plus resveratrol (Res, 5 mg·kg-1·d-1) for 14 weeks. After the rats were sacrificed, samples of bone tissues were collected. The changes in bone formation were assessed using Micro-CT, histomorphometry, and biomechanical assays. Expression of Kruppel-like factor 15 (KLF15), peroxisome proliferator-activated receptor γ 2 (PPARγ 2) and other signaling proteins in skeletal tissue was measured with Western blotting and quantitative RT-PCR. GC treatment markedly increased the expression of KLF15, PPARγ2, C/EBPα and aP2, which were related to adipogenesis, upregulated FoxO3a pathway proteins (FoxO3a and Gadd45a), and suppressed the canonical Wnt signaling (ß-catenin and Axin2), which was required for osteogenesis. Thus, GC significantly decreased bone mass and bone quality. Co-treatment with Tan or Res effectively counteracted GC-impaired bone formation, suppressed GC-induced adipogenesis, and restored abnormal expression of the signaling molecules in GIO rats. We conclude that tanshinol counteracts GC-decreased bone formation by inhibiting marrow adiposity via the KLF15/PPARγ2/FoxO3a/Wnt pathway.
Assuntos
Adipogenia/efeitos dos fármacos , Ácidos Cafeicos/uso terapêutico , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Via de Sinalização Wnt/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Medula Óssea/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Regulação para Baixo , Proteínas de Ligação a Ácido Graxo/genética , Feminino , Proteína Forkhead Box O3/genética , Fatores de Transcrição Kruppel-Like/genética , PPAR gama/genética , Prednisona/administração & dosagem , Prednisona/farmacologia , Ratos Sprague-Dawley , Resveratrol , Estilbenos/administração & dosagem , Estilbenos/farmacologia , Regulação para Cima , Via de Sinalização Wnt/genéticaRESUMO
Cyclic peptides hold great potential as therapeutic agents and research tools, but their broad application has been limited by poor membrane permeability. Here, we report a potentially general approach for intracellular delivery of cyclic peptides. Short peptide motifs rich in arginine and hydrophobic residues (e.g., FΦRRRR, where Φ is l-2-naphthylalanine), when embedded into small- to medium-sized cyclic peptides (7-13 amino acids), bound to the plasma membrane of mammalian cultured cells and were subsequently internalized by the cells. Confocal microscopy and a newly developed peptide internalization assay demonstrated that cyclic peptides containing these transporter motifs were translocated into the cytoplasm and nucleus at efficiencies 2-5-fold higher than that of nonaarginine (R(9)). Furthermore, incorporation of the FΦRRRR motif into a cyclic peptide containing a phosphocoumaryl aminopropionic acid (pCAP) residue generated a cell permeable, fluorogenic probe for detecting intracellular protein tyrosine phosphatase activities.
Assuntos
Sistemas de Liberação de Medicamentos , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo , Motivos de Aminoácidos , Membrana Celular/metabolismo , Humanos , Células MCF-7 , Microscopia Confocal , Conformação Molecular , Peptídeos Cíclicos/síntese química , Células Tumorais CultivadasRESUMO
The selective increase of Na(+)/I(-) symporter (NIS)-mediated active iodide uptake in thyroid cells allows the use of radioiodine I(131) for diagnosis and targeted treatment of thyroid cancers. However, NIS-mediated radioiodine accumulation is often reduced in thyroid cancers due to decreased NIS expression/function. As PI3K signaling is overactivated in many thyroid tumors, we investigated the effects of inhibitors for PI3K, Akt, or mTORC1 as well as their interplay on NIS modulation in thyroid cells under chronic TSH stimulation. PI3K inhibition by LY294002 increased NIS-mediated radioiodide uptake (RAIU) mainly through upregulation of NIS expression, however, mTORC1 inhibition by Rapamycin did not increase NIS-mediated RAIU despite increased NIS protein levels. In comparison, Akt inhibition by Akti-1/2 did not increase NIS protein levels, yet markedly increased NIS-mediated RAIU by decreasing iodide efflux rate and increasing iodide transport rate and iodide affinity of NIS. The effects of Akti-1/2 on NIS-mediated RAIU are not detected in nonthyroid cells, implying that Akti-1/2 or its derivatives may represent potential pharmacological reagents to selectively increase thyroidal radioiodine accumulation and therapeutic efficacy.
Assuntos
Benzilaminas/farmacologia , Cromonas/farmacologia , Radioisótopos do Iodo/metabolismo , Morfolinas/farmacologia , Quinoxalinas/farmacologia , Sirolimo/farmacologia , Simportadores/metabolismo , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Células HEK293 , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , RNA Mensageiro/metabolismo , Ratos , Simportadores/genética , Serina-Treonina Quinases TOR , Glândula Tireoide/citologia , Tireotropina/farmacologiaRESUMO
Na(+)/I(-) symporter (NIS)-mediated iodide uptake into thyroid follicular cells serves as the basis of radioiodine therapy for thyroid cancer. NIS protein is also expressed in the majority of breast tumors, raising potential for radionuclide therapy of breast cancer. KT5823, a staurosporine-related protein kinase inhibitor, has been shown to increase thyroid-stimulating hormone-induced NIS expression, and thus iodide uptake, in thyroid cells. In this study, we found that KT5823 does not increase but decreases iodide uptake within 0.5 h of treatment in trans-retinoic acid and hydrocortisone-treated MCF-7 breast cancer cells. Moreover, KT5823 accumulates hypoglycosylated NIS, and this effect is much more evident in breast cancer cells than thyroid cells. The hypoglycosylated NIS is core glycosylated, has not been processed through the Golgi apparatus, but is capable of trafficking to the cell surface. KT5823 impedes complex NIS glycosylation at a regulatory point similar to brefeldin A along the N-linked glycosylation pathway, rather than targeting a specific N-glycosylated site of NIS. KT5823-mediated effects on NIS activity and glycosylation are also observed in other breast cancer cells as well as human embryonic kidney cells expressing exogenous NIS. Taken together, KT5823 will serve as a valuable pharmacological reagent to uncover mechanisms underlying differential NIS regulation between thyroid and breast cancer cells at multiple levels.
Assuntos
Neoplasias da Mama/metabolismo , Carbazóis/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Simportadores/metabolismo , Glândula Tireoide/citologia , Animais , Brefeldina A/farmacologia , Linhagem Celular , Feminino , Glicosilação , Humanos , Hidrocortisona , Iodetos/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , Ratos , Tireotropina , TretinoínaRESUMO
Selective iodide uptake and prolonged iodine retention in the thyroid is the basis for targeted radioiodine therapy for thyroid cancer patients; however, salivary gland dysfunction is the most frequent nonthyroidal complications. In this study, we have used noninvasive single photon emission computed tomography functional imaging to quantify the temporal dynamics of thyroidal and salivary radioiodine accumulation in mice. At 60â min post radionuclide injection, radionuclide accumulation in the salivary gland was generally higher than that in thyroid due to much larger volume of the salivary gland. However, radionuclide accumulation per anatomic unit in the salivary gland was lower than that in thyroid and was comparable among mice of different age and gender. Differently, radionuclide accumulation per anatomic unit in thyroid varied greatly among mice. The extent of thyroidal radioiodine accumulation stimulated by a single dose of exogenous bovine TSH (bTSH) in triiodothyronine (T3)-supplemented mice was much less than that in mice received neither bTSH nor T3 (nontreated mice), suggesting that the duration of elevated serum TSH level is important to maximize thyroidal radioiodine accumulation. Furthermore, the extent and duration of radioiodine accumulation stimulated by bTSH was less in the thyroids of the thyroid-targeted RET/PTC1 (thyroglobulin (Tg)-PTC1) mice bearing thyroid tumors compared with the thyroids in wild-type (WT) mice. Finally, the effect of 17-allyamino-17-demothoxygeldanamycin on increasing thyroidal, but not salivary, radioiodine accumulation was validated in both WT mice and Tg-PTC1 preclinical thyroid cancer mouse model.
Assuntos
Benzoquinonas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lactamas Macrocíclicas/farmacologia , Glândulas Salivares/diagnóstico por imagem , Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Animais , Modelos Animais de Doenças , Imageamento Tridimensional , Camundongos , Receptores Patched , Receptor Patched-1 , Receptores de Superfície Celular/fisiologia , Tireotropina/farmacologiaRESUMO
AIM: Previous studies have shown that D(+)beta-3,4-dihydroxyphenyl lactic acid (salvianic acid A, SAA) has anabolic effects on prednisone (GC)-induced osteoporosis in rats. The current study aims to investigate the molecular mechanism of SAA's impact on osteogenesis and adipogenesis in bone marrow stromal cells in intact and GC-treated rats. METHODS: For in vitro study, newborn rat calvaria osteoblasts (rOBs) and rat bone marrow stromal cells (rMSCs) were isolated, identified and cultured with SAA at different concentrations to evaluate SAA's influence on osteogenesis and adipogenesis. In addition, 3-month-old Sprague-Dawley (SD) male rats were treated with distilled water, prednisone alone (3.0 mgxkg(-1)xd(-1)) or prednisone (3.0 mgxkg(-1)xd(-1)) and SAA (25 mgxkg(-1)xd(-1)) for 45 d. At the end point, the different groups of rMSCs were isolated by density-gradient centrifugation and cultured. RESULTS: (1) At 0.1-10.0 mg/L, SAA increased ALP activity, type I collagen (Coll-I) mRNA and OPG mRNA expression and stimulated nodule mineralization of rOBs. SAA (0.5 mg/L) also significantly increased the ALP activity of rMSCs without a need for osteogenesis-inducing medium. At 5.0 mg/L, SAA decreased the number of adipocytes with less lipid droplet formation from the rMSCs, which typically undergo adipocyte induction. (2) Coll-I expression was markedly decreased, whereas lipoprotein lipase (LPL) mRNA expression increased by 98% when compared with the first generation of rMSCs in GC-treated rats. The SAA-treated rats demonstrated an over 2-fold increase in Coll-I expression when compared with intact rats and further showed a significant decrease in LPL expression when compared with GC-treated rats. When rMSCs were co-cultured with SAA (0.5 mg/L) in vitro, SAA did not affect Coll-I and LPL gene expression in intact rats but significantly increased Coll-I and decreased LPL gene expression in GC-treated rats. CONCLUSION: SAA protected bone from GC-induced bone marrow impairment by stimulating osteogenesis and depressing adipogenesis in bone marrow stromal cells both in vivo and in vitro. The data indicated that aqueous extract of Salvia miltiorrhiza, which include SAA, may serve as an active anabolic agent and a useful therapeutic strategy for the treatment of GC-associated osteoporosis.