RESUMO
OBJECTIVE. The purpose of this study was to evaluate the feasibility of ultrasound (US)-guided percutaneous transhepatic cholangial drainage (PTCD) and consequent percutaneous US cholangiography in managing the dilated biliary tracts of children who have undergone hepatobiliary surgery. SUBJECTS AND METHODS. Sixteen children (11 boys, five girls; age range, 3-144 months) who underwent hepatobiliary surgery from December 2016 to October 2018 and had US evidence of biliary dilatation were included. All patients had undergone US-guided PTCD because of elevated postoperative serum bilirubin levels or bile duct infection. Immediately after the PTCD procedure, diluted sulphur hexafluoride microbubbles dispersion was injected through the PTCD tube to evaluate the anastomosis and the intrahepatic bile duct tree. Laboratory results, including those of serum bilirubin measurement, liver function tests, and routine blood tests, were evaluated before and after PTCD. Nine of 16 patients also underwent percutaneous transhepatic cholangiography (PTC). The percutaneous US cholangiography findings were evaluated and compared with the PTC findings. RESULTS. Liver enzyme levels decreased after PTCD with a statistically significant difference from the values before PTCD. Percutaneous US cholangiography showed that the anastomosis in 6 of the 16 patients (37.5%) was patent and depicted the morphologic featuresof intrahepatic bile duct tree in five of these patients. In the other 10 patients, the anastomosis was completely obstructed, and percutaneous US cholangiography depicted the morphologic features of intrahepatic bile duct tree in eight patients. In the nine patients who underwent PTC, the percutaneous US cholangiographic findings were the same as the PTC findings. CONCLUSION. US-guided PTCD is helpful in relieving jaundice and inflammation in children who have undergone hepatobiliary surgery and have biliary dilatation. Findings at consequent percutaneous US cholangiography are comparable to those of PTC in depicting the anastomosis in these patients.
Assuntos
Doenças Biliares/cirurgia , Colangiografia , Drenagem/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/terapia , Ultrassonografia de Intervenção , Ductos Biliares Intra-Hepáticos , Bilirrubina/sangue , Criança , Pré-Escolar , Meios de Contraste , Dilatação Patológica , Estudos de Viabilidade , Feminino , Humanos , Lactente , Testes de Função Hepática , Masculino , MicrobolhasRESUMO
PARP1 inhibitors (PARPis) are used clinically during cancer therapy and are thought to exert their cytotoxicity through PARP1 polymerase inhibition and PARP1-DNA trapping. Here, we showed no significant correlation between PARP1-DNA trapping and cytotoxicity induced by PARPis. We complemented PARP1-knockout sublines with wild-type PARP1 and 11 mutants with different point mutations that affect the polymerase activity. When examining the PARPi talazoparib, the induced cytotoxicity was highly significantly correlated with cellular PARP1 polymerase activity, but not with its PARP1-DNA trapping or polymerase inhibition. Similarly, talazoparib's PARP1-DNA trapping revealed significant correlation with the polymerase activity rather than its inhibition. Differently, however, when evaluating purified wild-type and mutated PARP1, we identified an almost linear relationship between PARPis' inhibiting PARP1 dissociation from DNA and their cytotoxicity in 17 cancer cell lines. In contrast, no significant correlation existed between PARP1 polymerase inhibition in the histone-based systems and the cytotoxicity. After careful comparisons on different methods and detection targets, we conclude that the PARPi-mediated increase in PARP1-DNA binding by inhibiting autoPARylation of PARP1 on DNA rather than in PARP1-DNA trapping is correlated with PARPi's cytotoxicity. Accordingly, we established a new PARPi screening model that more closely predicts cytotoxicity.
Assuntos
DNA de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Linhagem Celular Tumoral , DNA de Neoplasias/genética , Ensaios de Seleção de Medicamentos Antitumorais , Técnicas de Silenciamento de Genes , Humanos , NAD/metabolismo , Neoplasias/genética , Ftalazinas/farmacologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/genéticaRESUMO
With increasing uses of poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi) for cancer therapy, understanding their resistance is becoming urgent. However, acquired PARPi resistance in the phosphatase and tensin homolog (PTEN)-deficient background is poorly understood. We generated 3 PARPi-resistant PTEN-deficient glioblastoma U251 variants separately with olaparib (U251/OP), talazoparib (U251/TP) and simmiparib (U251/SP). These variants displayed consistent resistance (2.46-71.78-fold) to all 5 PARPi, including niraparib and rucaparib, and showed higher degrees of resistance to the PARPi to which the parental cells were more sensitive. The resistance was characteristic of fast emergence and high stability. However, the resistance acquirement did not cause an increasingly aggressive phenotype. The resistance was not correlated to various factors, including PTEN mutations. The PARPi-treated variants produced less γH2AX and G2/M arrest. Consistently, loss of 53BP1 occurred in all variants and its compensation enhanced their sensitivity to PARPi by approximately 76%. The variants revealed slightly different cross-resistance profiles to 13 non-PARPi anticancer drugs. All were resistant to Ara-C (6-8-fold) but showed differential resistance to 5-fluorouracil, gemcitabine and paclitaxel. Almost no resistance was observed to the rest drugs, including cisplatin. SAMHD1 was overexpressed in all the variants and its knockout completely restored their sensitivity to Ara-C but did not affect their PARPi sensitivity. The present study demonstrates a consistent resistance profile to PARPi and a unique cross-resistance profile to non-PARPi drugs in different PARPi-resistant U251 cells and reveals 53BP1 loss and SAMHD1 overexpression as the primary mechanisms responsible for their resistance to PARPi and Ara-C, respectively. These effects probably result from heritable gene change(s) caused by persistent PARPi exposure.
Assuntos
Antineoplásicos/farmacologia , Citarabina/farmacologia , Glioblastoma/genética , PTEN Fosfo-Hidrolase/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteína 1 com Domínio SAM e Domínio HD/genética , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Humanos , PTEN Fosfo-Hidrolase/deficiência , Ftalazinas/farmacologia , Piperazinas/farmacologiaRESUMO
Purpose To evaluate the feasibility of ultrasonographically (US) guided percutaneous cholecystocholangiography (PCC) for early exclusion of biliary atresia (BA) in infants suspected of having BA with equivocal US findings or indeterminate type of BA and a gallbladder longer than 1.5 cm at US. Materials and Methods This study was approved by the ethics committee; written informed parental consent was obtained. From February 2016 to December 2016, nine infants (four boys, five girls; mean age, 60.2 days; median age, 57 days; age range, 23-117 days) with conjugated hyperbilirubinemia and gallbladder longer than 1.5 cm at US were referred for US-guided PCC after US findings were equivocal for BA (n = 7) or the type of BA was unclear (n = 2). PCC was performed with a US machine with incorporated contrast pulse sequencing, contrast-specific software, and a linear transducer by injecting diluted contrast material via an 18-gauge needle. Images from US and US-guided PCC were evaluated in consensus by two radiologists. US criteria for BA were fibrotic cord sign (>2 mm) and gallbladder length-to-width ratio greater than 5.2. BA was excluded at PCC when contrast material was visualized in the gallbladder, common hepatic ducts, and common bile duct and during passage to the duodenum. Patients in whom BA was diagnosed after PCC underwent surgery or liver biopsy as the reference standard. Nonparametric and Fisher exact tests were used. Results US-guided PCC was successful in all patients. There were no procedural-related complications. BA was excluded in five of the nine patients. The median serum direct bilirubin level in these patients slightly decreased 1 week after PCC, from 91.1 µmol/L (interquartile range [IQR], 81.6-113.8 µmol/L) to 65.3 µmol/L (IQR, 57.8-74.7 µmol/L); however, this difference was not statistically significant (P = .062). BA was diagnosed in four patients, with the diagnosis confirmed at surgery (n = 2) or liver biopsy (n = 2). BA in two patients with unclear type of BA was defined as type III without patency of the common bile duct in one patient and as type III with patency of the common bile duct in the other. Conclusion In this highly selected group of infants with indeterminate type of BA or inconclusive US findings, US-guided PCC enabled the diagnosis of BA in four infants and the exclusion of BA in five. US-guided PCC may be a safe and effective tool to exclude BA early in infants with equivocal US findings. © RSNA, 2017.
Assuntos
Atresia Biliar/diagnóstico por imagem , Colangiografia/métodos , Colecistografia/métodos , Vesícula Biliar/diagnóstico por imagem , Microbolhas/uso terapêutico , Ultrassonografia de Intervenção/métodos , Atresia Biliar/cirurgia , Bilirrubina/sangue , Feminino , Vesícula Biliar/anormalidades , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Estudos RetrospectivosRESUMO
BACKGROUND: Several types of congenital lesions can cause complete or incomplete obstruction of the intestine. Our purpose is to present 3 neonates with dual intestinal type I atresia, i.e., simultaneous obstructive lesions at 2 locations in which the atresia manifested as diaphragm-like tissue. CASE PRESENTATION: All 3 cases were female infants ranging in age from 2 to 14 months. The common symptom in all cases was intermittent persistent vomiting. In some cases the vomitus was bilious, and other symptoms included abdominal distention and delayed meconium passage. Prior surgeries at another hospital were unsuccessful at relieving the symptoms in one case. One case had dual lesions in the colon, one dual lesions in the duodenum, and one atresia at both the distal portion of the ileum and the descending colon. Surgical exploration and removal of the lesions at our hospital was successful in all cases, and the infants were discharged in good condition. CONCLUSIONS: Type I atresia can manifest as a diaphragm-like tissue obstructing the continuity of gastrointestinal tract, and in rare cases multiple areas may be present. Base on the intermittent nature of the associated symptoms, diagnosis can be difficult and is often delayed. Physicians should be aware of this condition during the work-up of an infant with persistent intermittent vomiting.
Assuntos
Doenças do Colo/cirurgia , Duodenopatias/cirurgia , Doenças do Íleo/cirurgia , Atresia Intestinal/cirurgia , Obstrução Intestinal/cirurgia , Sulfato de Bário , Colo/anormalidades , Doenças do Colo/diagnóstico por imagem , Doenças do Colo/etiologia , Meios de Contraste , Duodenopatias/diagnóstico por imagem , Duodenopatias/etiologia , Duodeno/anormalidades , Enema , Feminino , Humanos , Doenças do Íleo/diagnóstico por imagem , Doenças do Íleo/etiologia , Íleo/anormalidades , Lactente , Atresia Intestinal/complicações , Atresia Intestinal/diagnóstico por imagem , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/etiologia , Tomografia Computadorizada por Raios XRESUMO
Poly-ADP-ribose polymerase (PARP) inhibitors (PARPi) have shown great promise for treating BRCA-deficient tumors. However, over 40% of BRCA-deficient patients fail to respond to PARPi. Here, we report that thioparib, a next-generation PARPi with high affinity against multiple PARPs, including PARP1, PARP2, and PARP7, displays high antitumor activities against PARPi-sensitive and -resistant cells with homologous recombination (HR) deficiency both in vitro and in vivo. Thioparib treatment elicited PARP1-dependent DNA damage and replication stress, causing S-phase arrest and apoptosis. Conversely, thioparib strongly inhibited HR-mediated DNA repair while increasing RAD51 foci formation. Notably, the on-target inhibition of PARP7 by thioparib-activated STING/TBK1-dependent phosphorylation of STAT1, triggered a strong induction of type I interferons (IFNs), and resulted in tumor growth retardation in an immunocompetent mouse model. However, the inhibitory effect of thioparib on tumor growth was more pronounced in PARP1 knockout mice, suggesting that a specific PARP7 inhibitor, rather than a pan inhibitor such as thioparib, would be more relevant for clinical applications. Finally, genome-scale CRISPR screening identified PARP1 and MCRS1 as genes capable of modulating thioparib sensitivity. Taken together, thioparib, a next-generation PARPi acting on both DNA damage response and antitumor immunity, serves as a therapeutic potential for treating hyperactive HR tumors, including those resistant to earlier-generation PARPi.
Assuntos
Interferon Tipo I , Neoplasias , Animais , Camundongos , Linhagem Celular Tumoral , Reparo do DNA , Recombinação Homóloga , Interferon Tipo I/genética , Interferon Tipo I/uso terapêutico , Neoplasias/genética , Ftalazinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Reparo de DNA por Recombinação , Proteínas de Ligação a RNA/genética , Resistencia a Medicamentos AntineoplásicosRESUMO
N6-methyladenosine (m6A) RNA methylation and its associated methyltransferase METTL3 play an important role in tumorigenesis of a series of tumors. However, dysregulation of METTL3 in gallbladder cancer (GBC) remains obscure. Here, we showed that upregulated METTL3 level predicted poor prognosis and correlated with increased lymphatic metastasis and high TNM stage. Functionally, we found that METTL3 could promote cell proliferation, invasion, and migration of GBC-SD and NOZ cells. Mechanistically, we revealed the METTL3-mediated m6A-modification profile in GBC cells and identified DUSP5 as the downstream gene of METTL3. METTL3 promoted the degradation of DUSP5 mRNA in a YTHDF2-dependent manner. Rescue assays showed that downregulation of DUSP5 could attenuate the knockdown METTL3-mediated inhibition of cell proliferation, invasion, and migration of GBC-SD and NOZ cells. Thus, our finding shows that elevated METTL3 expression contributes to tumor aggression in GBC, suggesting that METTL3 is a possible prognostic predictor and therapeutic target against GBC.
Assuntos
Fosfatases de Especificidade Dupla , Neoplasias da Vesícula Biliar , Metiltransferases , Adenosina/análogos & derivados , Adenosina/genética , Fosfatases de Especificidade Dupla/genética , Neoplasias da Vesícula Biliar/genética , Neoplasias da Vesícula Biliar/patologia , Humanos , Metiltransferases/genética , RNA Mensageiro/genéticaRESUMO
PARP1 and Chk1 inhibitors have been shown to be synergistic in different cancer models in relatively short time treatment modes. However, the consequences of long-term/repeated treatments with the combinations in cancer models remain unclear. In this study, the synergistic cytotoxicity of their combinations in 8 tumor cell lines was confirmed in a 7-day exposure mode. Then, pancreatic Capan-1 cells were repeatedly treated with the PARP1 inhibitor olaparib, the Chk1 inhibitor rabusertib or their combination for 211-214 days, during which the changes in drug sensitivity were monitored at a 35-day interval. Unexpectedly, among the 3 treatment modes, the combination treatments resulted in the highest-grade resistance to Chk1 (~14.6 fold) and PARP1 (~420.2 fold) inhibitors, respectively. Consistently, G2/M arrest and apoptosis decreased significantly in the resulting resistant variants exposed to olaparib. All 3 resistant variants also unexpectedly obtained enhanced migratory and invasive capabilities. Moreover, the combination treatments resulted in increased migration and invasion than olaparib alone. The expression of 124 genes changed significantly in all the resistant variants. We further demonstrate that activating CXCL3-ERK1/2 signaling might contribute to the enhanced migratory capabilities rather than the acquired drug resistance. Our findings indicate that repeated treatments with the rabusertib/olaparib combination result in increased drug resistance and a more aggressive cell phenotype than those with either single agent, providing new clues for future clinical anticancer tests of PARP1 and Chk1 inhibitor combinations.
Assuntos
Apoptose , Inibidores de Poli(ADP-Ribose) Polimerases , Linhagem Celular Tumoral , Resistência a Medicamentos , Pontos de Checagem da Fase G2 do Ciclo Celular , Humanos , Ftalazinas/farmacologia , Poli(ADP-Ribose) Polimerase-1/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologiaRESUMO
BACKGROUND: Neuroblastoma (NBL) is the most common extra-cranial solid tumour in childhood, with prognosis ranging from spontaneous remission to high risk for rapid and fatal progression. Despite existing therapy approaches, the 5-year event-free survival (EFS) for patients with advanced NBL remains below 30%, emphasizing urgent necessary for novel therapeutic strategies. Studies have shown that epigenetic disorders play an essential role in the pathogenesis of NBL. However, the function and mechanism of N7-methylguanosine (m7G) methyltransferase in NBL remains unknown. METHODS: The expression levels of m7G tRNA methyltransferase Methyltransferase-like 1 (METTL1) were analyzed by querying the Gene Expression Omnibus (GEO) database and further confirmed by immunohistochemistry (IHC) assay. Kaplan-Meier, univariate and multivariate cox hazard analysis were performed to reveal the prognostic role of METTL1. Cell function assays were performed to evaluate how METTL1 works in proliferation, apoptosis and migration in cell lines and xenograft mouse models. The role of METTL1 on mRNA translation activity of NBL cells was measured using puromycin intake assay and polysome profiling assay. The m7G modified tRNAs were identified by tRNA reduction and cleavage sequencing (TRAC-seq). Ribosome nascent-chain complex-bound mRNA sequencing (RNC-seq) was utilized to identify the variation of gene translation efficiency (TE). Analyzed the codon frequency decoded by m7G tRNA to clarify the translation regulation and mechanism of m7G modification in NBL. RESULTS: This study found that METTL1 were significantly up-regulated in advanced NBL, which acted as an independent risk factor and predicted poor prognosis. Further in NBL cell lines and BALB/c-nu female mice, we found METTL1 played a crucial role in promoting NBL progression. Furthermore, m7G profiling and translation analysis revealed downregulation of METTL1 would inhibit puromycin intake efficiency of NBL cells, indicating that METTL1 did count crucially in regulation of NBL cell translation. With all tRNAs with m7G modification identified in NBL cells, knockdown of METTL1 would significantly reduce the levels of both m7G modification and m7G tRNAs expressions. Result of RNC-seq shew there were 339 overlapped genes with impaired translation in NBL cells upon METTL1 knockdown. Further analysis revealed these genes contained higher frequency of codons decoded by m7G-modified tRNAs and were enriched in oncogenic pathways. CONCLUSION: This study revealed the critical role and mechanism of METTL1-mediated tRNA m7G modification in regulating NBL progression, providing new insights for developing therapeutic approaches for NBL patients.
RESUMO
A novel flavone, named 4'-methoxy-3',5,7-trihydroxy-8-(1''-(3''',4''',5'''-trihydroxyphenyl)ethyl)flavone (1), was isolated from Sarcopyramis nepalensis, along with two known compounds syringaresinol (2) and aralidioside (3). Their structures were established by the spectroscopic analysis, especially by 2D NMR. All of the three compounds were isolated from the plant for the first time.
Assuntos
Flavonas/isolamento & purificação , Melastomataceae/química , Flavonas/química , Furanos/química , Furanos/isolamento & purificação , Lignanas/química , Lignanas/isolamento & purificação , Estrutura Molecular , Ressonância Magnética Nuclear BiomolecularRESUMO
Bioluminescent proteins (BLPs) are a class of proteins that widely distributed in many living organisms with various mechanisms of light emission including bioluminescence and chemiluminescence from luminous organisms. Bioluminescence has been commonly used in various analytical research methods of cellular processes, such as gene expression analysis, drug discovery, cellular imaging, and toxicity determination. However, the identification of bioluminescent proteins is challenging as they share poor sequence similarities among them. In this paper, we briefly reviewed the development of the computational identification of BLPs and subsequently proposed a novel predicting framework for identifying BLPs based on eXtreme gradient boosting algorithm (XGBoost) and using sequence-derived features. To train the models, we collected BLP data from bacteria, eukaryote, and archaea. Then, for getting more effective prediction models, we examined the performances of different feature extraction methods and their combinations as well as classification algorithms. Finally, based on the optimal model, a novel predictor named iBLP was constructed to identify BLPs. The robustness of iBLP has been proved by experiments on training and independent datasets. Comparison with other published method further demonstrated that the proposed method is powerful and could provide good performance for BLP identification. The webserver and software package for BLP identification are freely available at http://lin-group.cn/server/iBLP.
Assuntos
Algoritmos , Proteínas Luminescentes , Sequência de Aminoácidos , Fenômenos Químicos , Biologia Computacional , Bases de Dados de Proteínas , Descoberta de Drogas , Luminescência , Proteínas Luminescentes/química , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Aprendizado de Máquina , SoftwareRESUMO
ABSTRACT: Although some studies have reported the expression and clinical significance of phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in breast cancer tissues, it is still controversial whether p-STAT3 play a role in promoting or suppressing cancer. Here, we used immunohistochemistry analysis to explore expression of p-STAT3 in 407 cases of breast cancer, and analyzed the relationship between p-STAT3 expression and the clinicopathological characteristics and prognosis of breast cancer patients. Positive p-STAT3 expression was seen in 112 cases (27.5%) of breast cancer. p-STAT3 expression was negatively correlated with tumor size, tumor stage and human epidermal growth factor receptor 2 (HER2) status, and the positive rate of p-STAT3 was lowest in HER2-enriched subtype breast cancer (15.3%), while other subtypes were luminal B (23.0%), luminal A (30.2%), and triple-negative breast cancer (TNBC) (37.5%). Logistic regression model multivariate analysis showed that the independent correlation factor of p-STAT3 expression in breast cancer was tumor size (ORâ=â0.187, 95% CIâ=â0.042-0.839, Pâ=â.029) and HER2 status (ORâ=â0.392, 95% CIâ=â0.216-0.710, Pâ=â.002). In this study, no clear relationship was observed between patients' prognosis and expression of p-STAT3. Therefore, we suggest that p-STAT3 expression in breast cancer is negatively correlated with tumor size and HER2 status, but appears to have no effect on survival.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Receptor ErbB-2/metabolismo , Fator de Transcrição STAT3/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/mortalidade , China/epidemiologia , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Mastectomia , Pessoa de Meia-Idade , Fosforilação , Prognóstico , Receptor ErbB-2/análise , Fator de Transcrição STAT3/análise , Análise Serial de Tecidos , Carga TumoralRESUMO
Monotherapy with poly ADP-ribose polymerase (PARP) inhibitors results in a limited objective response rate (≤60% in most cases) in patients with homologous recombination repair (HRR)-deficient cancer, which suggests a high rate of resistance in this subset of patients to PARP inhibitors (PARPi). To overcome resistance to PARPi and to broaden their clinical use, we performed high-throughput screening of 99 anticancer drugs in combination with PARPi to identify potential therapeutic combinations. Here, we found that GSK3 inhibitors (GSK3i) exhibited a strong synergistic effect with PARPi in a panel of colorectal cancer (CRC) cell lines with diverse genetic backgrounds. The combination of GSK3ß and PARP inhibition causes replication stress and DNA double-strand breaks, resulting in increased anaphase bridges and abnormal spindles. Mechanistically, inhibition or genetic depletion of GSK3ß was found to impair the HRR of DNA and reduce the mRNA and protein level of BRCA1. Finally, we demonstrated that inhibition or depletion of GSK3ß could enhance the in vivo sensitivity to simmiparib without toxicity. Our results provide a mechanistic understanding of the combination of PARP and GSK3 inhibition, and support the clinical development of this combination therapy for CRC patients.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Sinergismo Farmacológico , Feminino , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HCT116 , Células HT29 , Células HeLa , Recombinação Homóloga/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Inibidores de Poli(ADP-Ribose) Polimerases/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Distribuição Aleatória , Transfecção , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
OBJECTIVE: To compare the outcome of biliary atresia (BA) patients with and without hilar cyst on preoperative ultrasound. METHODS: A single center retrospective review of patients of BA with (n = 27) and without hilar cyst (n = 27) over a 5 y period was done. The patients were analyzed using propensity score matching to reduce selection bias. All patients were diagnosed as type III BA by histologic examination and cholangiograms. Clinicopathological characteristics and survival outcomes were compared between the two groups. RESULTS: There were no significant intergroup differences between baseline characteristics and outcomes after Kasai portoenterostomy surgery in two groups. BA with hilar cyst group showed comparable survival outcomes to the BA without cyst group (cumulative 1-y, 2-y and 5-y overall survival rates with native liver 61.4% vs. 65.8%, P = 0.041; 45.0% vs. 49.0%, P = 0.57; 45.0% vs. 49.0%, P = 0.57). And the Kaplan-Meier survival curves showed no significant difference in cumulative survival with native liver between the two groups (P = 0.58). CONCLUSIONS: Type III BA with hilar cyst had no better prognosis compared with Type III BA without cyst.
Assuntos
Atresia Biliar , Cistos , Atresia Biliar/complicações , Atresia Biliar/diagnóstico , Atresia Biliar/cirurgia , Cistos/cirurgia , Humanos , Lactente , Portoenterostomia Hepática , Prognóstico , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Six new oxygenated daphnane-type diterpenoids, trigoxyphins A-F (1-6), a phenanthrene-type diterpenoid, trigoxyphin G (7), and two known compounds were isolated from twigs of Trigonostemon xyphophylloides. Their structures were established using spectroscopic methods. Compounds 1 and 2 exhibited strong cytotoxic activity against HL60 (IC(50): 0.27 and 0.49 microM) and A549 (IC(50): 7.5 and 4.9 microM) tumor cell lines, respectively.
Assuntos
Diterpenos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Euphorbiaceae/química , Fenantrenos/isolamento & purificação , Diterpenos/química , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Células HL-60 , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Fenantrenos/química , Fenantrenos/farmacologia , Caules de Planta/químicaRESUMO
Poly(ADP-ribose) polymerase 1 (PARP1) regulates gene transcription in addition to functioning as a DNA repair factor. Forkhead box O1 (FoxO1) is a transcription factor involved in extensive biological processes. Here, we report that PARP1 binds to two separate motifs on the FoxO1 promoter and represses its transcription in a polymerase-independent manner. Using PARP1-knock out (KO) cells, wild-type-PARP1-complemented cells and catalytic mutant PARP1E988K-reconstituted cells, we investigated transcriptional regulation by PARP1. PARP1 loss led to reduced DNA damage response and ~362-fold resistance to five PARP inhibitors (PARPis) in Ewing sarcoma cells. RNA sequencing showed 492 differentially expressed genes in a PARP1-KO subline, in which the FoxO1 mRNA levels increased up to more than five times. The change in the FoxO1 expression was confirmed at both mRNA and protein levels in different PARP1-KO and complemented cells. Moreover, exogenous PARP1 overexpression reduced the endogenous FoxO1 protein in RD-ES cells. Competitive EMSA and ChIP assays revealed that PARP1 specifically bound to the FoxO1 promoter. DNase I footprinting, mutation analyses, and DNA pulldown FREP assays showed that PARP1 bound to two particular nucleotide sequences separately located at -813 to -826 bp and -1805 to -1828 bp regions on the FoxO1 promoter. Either the PARPi olaparib or the PARP1 catalytic mutation (E988K) did not impair the repression of PARP1 on the FoxO1 expression. Exogenous FoxO1 overexpression did not impair cellular PARPi sensitivity. These findings demonstrate a new PARP1-gene promoter binding mode and a new transcriptional FoxO1 gene repressor.
Assuntos
Proteína Forkhead Box O1/genética , Regulação da Expressão Gênica/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Sarcoma de Ewing/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Dano ao DNA/efeitos dos fármacos , Proteína Forkhead Box O1/metabolismo , Técnicas de Inativação de Genes , Humanos , Mutação , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Regiões Promotoras Genéticas , Ligação Proteica , Sarcoma de Ewing/genética , Regulação para CimaRESUMO
Several poly(ADP ribose) polymerase (PARP) inhibitors (PARPi) have been approved for cancer therapy; however, intrinsic and acquired resistance has limited their efficacy in the clinic. In fact, cancer cells have developed multiple mechanisms to overcome PARPi cytotoxicity in even a single cancer cell. In this study, we generated three PARPi-resistant BRCA2-deficient pancreatic Capan-1 variant cells using olaparib (Capan-1/OP), talazoparib (Capan-1/TP), and simmiparib (Capan-1/SP). We identified novel mutations in intron 11 of BRCA2, which resulted in the expression of truncated BRCA2 splice isoforms. Functional studies revealed that only a fraction (32-49%) of PARPi sensitivity could be rescued by depletion of BRCA2 isoforms. In addition, the apoptosis signals (phosphatidylserine eversion, caspase 3/7/8/9 activation, and mitochondrial membrane potential loss) were almost completely abrogated in all PARPi-resistant variants. Consistently, overexpression of the anti-apoptotic proteins cyclooxygenase 2 (COX-2) and baculoviral IAP repeat-containing 3 (BIRC3) occurred in these variants. Depletion of COX-2 or BIRC3 significantly reduced apoptotic resistance in the PARPi-resistant sublines and reversed PARPi resistance by up to 70-72%. Furthermore, exogenous addition of prostaglandin E2, a major metabolic product of COX-2, inhibited PARPi-induced apoptotic signals; however, when combined with the BIRC3 inhibitor LCL161, there was significantly enhanced sensitivity of the resistant variants to PARPi. Finally, PARPi treatment or PARP1 depletion led to a marked increase in the mRNA and protein levels of COX-2 and BIRC3, indicating that PARP1 is a negative transcriptional regulator of these proteins. Together, our findings demonstrated that during the chronic treatment of cells with a PARPi, both BRCA2 intron 11 mutations and COX-2/BIRC3-mediated apoptotic resistance led to PARPi resistance in pancreatic Capan-1 cells.
RESUMO
OBJECTIVE: To study the expression of IL13RA2 in gliomas and to analyze its correlation with clinicopathological/molecular features, immune cell infiltration and prognostic significance. METHODS: mRNA expression data for IL13RA2 were downloaded and analyzed from two open access datasets (TCGA & CGGA). IL13RA2 protein expression was examined by immunohistochemistry. The association between IL13RA2 and important clinicopathological/molecular markers was examined using χ2 and Spearman correlation tests. The TIMER tool was used to evaluate the correlation of IL13RA2 with multiple intra-tumoral immune cell types in glioma. Kaplan-Meier test and multivariate Cox analyses were applied to evaluate the prognosis. RESULTS: Out of the 297 glioma tissues and 20 normal brain tissues in our cohort, IL13RA2 protein was highly expressed in 115 glioma tissues (115/297, 38.7%), but no expression was detected in normal brain tissues (0/20, 0%). The expression of IL13RA2 was significantly higher in GBMs (P<0.001). More than half of GBMs (68/132, 51.5%) were high expression of IL13RA2 protein, especially GBM patients with IDH wild-type and TERT promoter mutated (60/78, 76.9%). Moreover, 11/13 (84.6%) diffuse midline gliomas and 31/51 (64.7%) IDH wild-type LGGs also highly expressed IL13RA2 in our cohorts. Chi-square test showed that the expression of IL13RA2 was correlated with patient age, WHO grade, Ki67 index, IDH status, TERT promoter status and immune cell infiltration. Additionally, IL13RA2 was strongly associated with patients' OS and served as a negative prognostic marker in infiltrating gliomas. CONCLUSION: IL13RA2 was high expression in some glioma subtypes, and significantly correlated with poor prognosis. Based on its role in CAR-T therapy, it might act as an extremely important and specific therapeutic target for human malignant gliomas, especially in IDH wild-type LGG, "IDH wild-type and TERT promoter mutated" GBM and H3K27M-mutated diffuse midline glioma, and improve the clinical outcomes of these patients.
RESUMO
Intrahepatic cholangiocarcinoma (ICC) is a lethal malignancy with high mortality and lack of effective therapeutic targets. Here, we found that expression of cyclin-dependent kinase 7 (CDK7) was significantly associated with higher tumor grade and worse prognosis in 96 ICC specimens. Depletion of CDK7 significantly inhibited cell growth, induced a G2/M cell cycle arrest, and reduced the migratory and invasive potential in ICC cells. Subsequent experiments demonstrated that ICC cells were highly sensitive to the CDK7 inhibitor THZ1. A low concentration of THZ1 markedly inhibited cell growth, cell cycle, migration, and invasion in ICC cell lines. RNA-sequencing (RNA-seq) analysis revealed that THZ1 treatment decreased the levels of massive oncogene transcripts, particularly those associated with cell cycle and cell migration. Quantitative reverse transcriptase PCR (qRT-PCR) analysis confirmed that transcription of oncogenes involved in cell cycle regulation (AURKA, AURKB, CDC25B, CDK1, CCNA2, and MKI67) and the c-Met pathway (c-Met, AKT1, PTK2, CRK, PDPK1, and ARF6) was selectively repressed by THZ1. In addition, THZ1 exhibited significant anti-tumor activity in a patient-derived xenograft (PDX) model of ICC, without causing detectable side effects.
Assuntos
Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Quinases Ciclina-Dependentes/metabolismo , Animais , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/genética , Movimento Celular/fisiologia , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Colangiocarcinoma/genética , Quinases Ciclina-Dependentes/genética , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , RNA-Seq , Reação em Cadeia da Polimerase em Tempo Real , Quinase Ativadora de Quinase Dependente de CiclinaRESUMO
Three new norlimonoids (1-3), two new tirucallane-type triterpenoids (4 and 5), and a new pimaradiene-type diterpenoid (6), along with two known limonoids and eight known tirucallane-type triterpenoids, were isolated from the leaves and twigs of Toona ciliata. Their structures were elucidated on the basis of spectroscopic data. Toonaciliatin M (6) showed moderate antifungal activity against Trichophyton rubrum with an MIC of 12.5 microg/mL.