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The transmembrane protein TMEM206 was recently identified as the molecular basis of the extracellular proton-activated Cl- channel (PAC), which plays an essential role in neuronal death in ischemia-reperfusion. The PAC channel is activated by extracellular acid, but the proton-sensitive mechanism remains unclear, although different acid-sensitive pockets have been suggested based on the cryo-EM structure of the human PAC (hPAC) channel. In the present study, we firstly identified two acidic amino acid residues that removed the pH-dependent activation of the hPAC channel by neutralization all the conservative negative charged residues located in the extracellular domain of the hPAC channel and some positively charged residues at the hotspot combined with two-electrode voltage-clamp (TEVC) recording in the Xenopus oocytes system. Double-mutant cycle analysis and double cysteine mutant of these two residues proved that these two residues cooperatively form a proton-sensitive site. In addition, we found that chloral hydrate activates the hPAC channel depending on the normal pH sensitivity of the hPAC channel. Furthermore, the PAC channel knock-out (KO) male mice (C57BL/6J) resist chloral hydrate-induced sedation and hypnosis. Our study provides a molecular basis for understanding the proton-dependent activation mechanism of the hPAC channel and a novel drug target of chloral hydrate.SIGNIFICANCE STATEMENT Proton-activated Cl- channel (PAC) channels are widely distributed in the nervous system and play a vital pathophysiological role in ischemia and endosomal acidification. The main discovery of this paper is that we identified the proton activation mechanism of the human proton-activated chloride channel (hPAC). Intriguingly, we also found that anesthetic chloral hydrate can activate the hPAC channel in a pH-dependent manner. We found that the chloral hydrate activates the hPAC channel and needs the integrity of the pH-sensitive site. In addition, the PAC channel knock-out (KO) mice are resistant to chloral hydrate-induced anesthesia. The study on PAC channels' pH activation mechanism enables us to better understand PAC's biophysical mechanism and provides a novel target of chloral hydrate.
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Hidrato de Cloral , Canales de Cloruro , Ratones , Animales , Masculino , Humanos , Hidrato de Cloral/farmacología , Canales de Cloruro/genética , Canales de Cloruro/metabolismo , Protones , Cloruros/metabolismo , Ratones Endogámicos C57BLRESUMEN
To report long-term results of a randomized controlled trial that compared cisplatin/fluorouracil/docetaxel (TPF) induction chemotherapy (IC) plus concurrent chemoradiotherapy (CCRT) with CCRT alone in locoregionally advanced nasopharyngeal carcinoma (NPC). Patients with stage III-IVB (except T3-4 N0) NPC were randomly assigned to receive IC plus CCRT (n = 241) or CCRT alone (n = 239). IC included three cycles of docetaxel (60 mg/m2 d1), cisplatin (60 mg/m2 d1), and fluorouracil (600 mg/m2 /d civ d1-5) every 3 weeks. Patients from both groups received intensity-modulated radiotherapy concurrently with three cycles of 100 mg/m2 cisplatin every 3 weeks. After a median follow-up of 71.5 months, the IC plus CCRT group showed significantly better 5-year failure-free survival (FFS, 77.4% vs. 66.4%, p = 0.019), overall survival (OS, 85.6% vs. 77.7%, p = 0.042), distant failure-free survival (88% vs. 79.8%, p = 0.030), and locoregional failure-free survival (90.7% vs. 83.8%, p = 0.044) compared to the CCRT alone group. Post hoc subgroup analyses revealed that beneficial effects on FFS were primarily observed in patients with N1, stage IVA, pretreatment lactate dehydrogenase ≥170 U/l, or pretreatment plasma Epstein-Barr virus DNA ≥6000 copies/mL. Two nomograms were further developed to predict the potential FFS and OS benefit of TPF IC. The incidence of grade 3 or 4 late toxicities was 8.8% (21/239) in the IC plus CCRT group and 9.2% (22/238) in the CCRT alone group. Long-term follow-up confirmed that TPF IC plus CCRT significantly improved survival in locoregionally advanced NPC with no marked increase in late toxicities and could be an option of treatment for these patients.
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Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Adolescente , Adulto , Quimioradioterapia , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Nomogramas , Pronóstico , Reproducibilidad de los Resultados , Adulto JovenRESUMEN
BACKGROUND: The value of adding cisplatin, fluorouracil, and docetaxel (TPF) induction chemotherapy to concurrent chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma is unclear. We aimed to compare TPF induction chemotherapy plus concurrent chemoradiotherapy with concurrent chemoradiotherapy alone in a suitably powered trial. METHODS: We did an open-label, phase 3, multicentre, randomised controlled trial at ten institutions in China. Patients with previously untreated, stage III-IVB (except T3-4N0) nasopharyngeal carcinoma, aged 18-59 years without severe comorbidities were enrolled. Eligible patients were randomly assigned (1:1) to receive induction chemotherapy plus concurrent chemoradiotherapy or concurrent chemoradiotherapy alone (three cycles of 100 mg/m2 cisplatin every 3 weeks, concurrently with intensity-modulated radiotherapy). Induction chemotherapy was three cycles of intravenous docetaxel (60 mg/m2 on day 1), intravenous cisplatin (60 mg/m2 on day 1), and continuous intravenous fluorouracil (600 mg/m2 per day from day 1 to day 5) every 3 weeks before concurrent chemoradiotherapy. Randomisation was by a computer-generated random number code with a block size of four, stratified by treatment centre and disease stage (III or IV). Treatment allocation was not masked. The primary endpoint was failure-free survival calculated from randomisation to locoregional failure, distant failure, or death from any cause; required sample size was 476 patients (238 per group). We did efficacy analyses in our intention-to-treat population. The follow-up is ongoing; in this report, we present the 3-year survival results and acute toxic effects. This trial is registered with ClinicalTrials.gov, number NCT01245959. FINDINGS: Between March 1, 2011, and Aug 22, 2013, 241 patients were assigned to induction chemotherapy plus concurrent chemoradiotherapy and 239 to concurrent chemoradiotherapy alone. After a median follow-up of 45 months (IQR 38-49), 3-year failure-free survival was 80% (95% CI 75-85) in the induction chemotherapy plus concurrent chemoradiotherapy group and 72% (66-78) in the concurrent chemoradiotherapy alone group (hazard ratio 0·68, 95% CI 0·48-0·97; p=0·034). The most common grade 3 or 4 adverse events during treatment in the 239 patients in the induction chemotherapy plus concurrent chemoradiotherapy group versus the 238 patients in concurrent chemoradiotherapy alone group were neutropenia (101 [42%] vs 17 [7%]), leucopenia (98 [41%] vs 41 [17%]), and stomatitis (98 [41%] vs 84 [35%]). INTERPRETATION: Addition of TPF induction chemotherapy to concurrent chemoradiotherapy significantly improved failure-free survival in locoregionally advanced nasopharyngeal carcinoma with acceptable toxicity. Long-term follow-up is required to determine long-term efficacy and toxicities. FUNDING: Shenzhen Main Luck Pharmaceuticals Inc, Sun Yat-sen University Clinical Research 5010 Program (2007037), National Science and Technology Pillar Program during the Twelfth Five-year Plan Period (2014BAI09B10), Health & Medical Collaborative Innovation Project of Guangzhou City (201400000001), Planned Science and Technology Project of Guangdong Province (2013B020400004), and The National Key Research and Development Program of China (2016YFC0902000).
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia , Quimioterapia de Inducción , Neoplasias Nasofaríngeas/terapia , Adulto , Carcinoma , Quimioradioterapia/efectos adversos , Cisplatino/administración & dosificación , Docetaxel , Femenino , Fluorouracilo/administración & dosificación , Humanos , Quimioterapia de Inducción/efectos adversos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidad , Taxoides/administración & dosificaciónRESUMEN
The objective of the study is to investigate the effects of the Numb/Notch signal pathway on the radiosensitivity of lung cancer cell line H358. MTT assay and colony forming assay were used to detect the effects of different doses of X-rays and MW167 on the in vitro proliferation of the lung cancer cell line H358. Flow cytometry was applied to evaluate the effects of X rays on the apoptosis of H358. Scratch assay and Transwell invasion assay were used to examine the effects of X-rays on the migration and invasion abilities of H358. The mRNA and protein expressions in the signal pathway were detected by real-time PCR and western blot. Assays in vitro confirmed the effects of the Numb/Notch pathway inhibitor on the radiosensitivity to lung cancer. MW167 enhanced the inhibiting effects of X-ray on the proliferation of H358 cell line. After the addition of MW167, the apoptosis rates significantly increased, but the invasion and migration abilities decreased significantly. Meanwhile, MW167 could dose-dependently promote the increase of expression of Numb, which is the upstream gene of the Numb/Notch signaling pathway, but inhibit the expression of and HES1. In vivo experiments revealed that cell proliferation was suppressed in the radiation, pathway inhibitor, and pathway inhibitor + radiation groups, and the pathway inhibitor + radiation group exhibited more active anti-tumor ability when compared with the blank group (all P < 0.05); Numb expression was up-regulated, but Notch1 and HES1 expressions were down-regulated in those three groups, and also, the pathway inhibitor + radiation group exhibited more significant alternation when compared with the blank group (all P < 0.05); cell apoptosis was promoted in those three groups, and the pathway inhibitor + radiation group showed more active apoptosis when compared with the blank group (all P < 0.05). Repression of the Numb/Notch pathway enhances the effects of radiotherapy on the radiosensitivity of the lung cancer cell line H358, and thus the Numb/Notch pathway may be a new target of radiotherapy for lung cancer.
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Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/radioterapia , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Tolerancia a Radiación , Receptores Notch/antagonistas & inhibidores , Transducción de Señal/efectos de la radiación , Animales , Apoptosis/efectos de la radiación , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Western Blotting , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Movimiento Celular/efectos de la radiación , Proliferación Celular/efectos de la radiación , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Radiación Ionizante , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Notch/genética , Receptores Notch/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
This study investigated the expression of nucleolin in tissue samples in patients with non-small cell lung cancer (NSCLC). Nucleolin was studied to determine whether it has a prognostic value and if its levels correlate with various clinicopathologic parameters. The relationship between nucleolin and expression of DNA-PKcs was also evaluated. Immunohistochemistry was used for detecting the expression levels of nucleolin and DNA-PKcs in tissues from 225 stage IA to IIIB NSCLC patients who underwent lung surgery. Nucleolin was observed predominantly in the cytoplasm, and some levels were observed in the nucleus. Nucleolin expression was higher in NSCLC tissues than adjacent normal lung tissues. Among 225 NSCLC patients, 117 (52.0 %) had high expression of nucleolin. The expression of nucleolin was significantly associated with pathologic stage (P = 0.013) and T status (P = 0.043). Multivariate analysis revealed that nucleolin, cytoplasmic nucleolin, and nuclear nucleolin expression were independent prognostic factors for both overall survival (OS) (P < 0.001) and disease-free survival (DFS) (P < 0.001). A high level of nuclear nucleolin served as an independent prognostic factor for better survival, while a high level of cytoplasmic nucleolin was closely associated with worse prognosis in NSCLC patients. The expression of nucleolin and cytoplasmic nucleolin positively correlated with DNA-PKcs (P < 0.001). These data suggest that nucleolin could be an effective treatment target and prognostic factor for patients with NSCLC.
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Carcinoma de Pulmón de Células no Pequeñas/patología , Proteína Quinasa Activada por ADN/metabolismo , Neoplasias Pulmonares/patología , Proteínas Nucleares/metabolismo , Fosfoproteínas/biosíntesis , Proteínas de Unión al ARN/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , NucleolinaRESUMEN
Analysis of synaptic strength and plasticity provides functional insights of complicated neural circuits. Here, we describe steps for cell- and projection-specific optogenetic manipulation of divergent basal ganglia circuits using anterograde and retrograde viral vectors. We quantitatively analyze synaptic function of these circuits utilizing a patch-clamp technique. This protocol is applicable to probe potential circuit targets for treatment of brain diseases. For complete details on the use and execution of this protocol, please refer to Ji et al.1.
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Ganglios Basales , Optogenética , Animales , Ratones , Optogenética/métodos , Técnicas de Placa-ClampRESUMEN
Background: Lymph node necrosis (LNN), including retropharyngeal nodal necrosis and cervical nodal necrosis, which is related to radiotherapy/ chemotherapy resistance, is a common phenomenon in nasopharyngeal carcinoma (NPC). This study was to assess the prognostic value of LNN at different N stages in NPC patients. Materials and Methods: In total, 1,665 newly diagnosed NPC patients at stage TxN1-3M0 from two centers were enrolled. Univariate and multivariate models were constructed to assess the association between LNN and long-term survival outcomes. The propensity score matching method was performed to balance treatment groups for baseline characteristics. Results: Of the 1,665, 540 patients (540/1665, 32.4%) were diagnosed with LNN, of which 54.1% (292/540) patients were at stage N1, 31.3% (169/540) at stage N2, and 14.6% (79/540) at stage N3. Univariate and multivariate analyses indicated LNN as an independent predictor for progressionfree survival (PFS), overall survival (OS), distant metastasis-free survival (DMFS), and locoregional relapse-free survival (LRRFS) in stage N1-3 patients (all P<0.001). When patients were analyzed according to stage, similar findings were observed for N1 patients (all P<0.001); for N2 patients, LNN independently predicted PFS (P=0.003), OS (P=0.011), and DMFS (P=0.004), and for stage N3, LNN only independently predicted LRRFS (P=0.019). 123 pairs of patients who received induction chemotherapy plus concurrent chemoradiotherapy or only concurrent chemoradiotherapy were matched, adding induction chemotherapy improved 5-year OS, PFS and LRFFS, but the results were not statistically significant. Conclusions: In NPC patients, LNN could independently predict poor prognosis at all N1-3 stages and at each N stage (N1 to N3). The value of adding induction chemotherapy to concurrent chemoradiotherapy in patients with LNN still requires further prospective studies.
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PURPOSE: To evaluate how prevertebral space involvement (PSI) and degree of tumor extension within the space affects prognosis in nasopharyngeal carcinoma (NPC). PARTICIPANTS AND METHODS: Data of patients with newly-diagnosed nonmetastatic NPC (n = 757) were retrospectively analyzed. Patients were separated into groups according to presence or absence of PSI and degree of tumor spread. Overall survival (OS), failure-free survival (FFS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) were compared between the groups. RESULTS: Prevalence of PSI, simple prevertebral muscle involvement (PMI), and behind prevertebral muscle involvement (BPMI) were 44.9% (340/757), 22.5% (170/757), and 22.5% (170/757), respectively. OS, FFS, LRFS, and DMFS for patients with and without PSI were 64% vs. 84.8%, 68% vs. 85.6%, 85.8% vs. 94.4%, and 78.5% vs. 92.8%, respectively (all P < 0.001). PSI was an independent predictor of OS, FFS, LRFS, and DMFS. OS, FFS, and DMFS for patients with simple PMI and with BPMI were 72.7% vs. 54.8% (P = 0.002), 75.8% vs. 59.8% (P = 0.003), and 85.5% vs. 71.2% (P = 0.002), respectively. Degree of PSI extension was related to OS, FFS, and DMFS. OS, FFS, LRFS, and DMFS were significantly poorer in patients with PSI in T2-3 stage than in patients without PSI in T3 stage (P < 0.05), but comparable to those in patients with T4 stage (P > 0.05). CONCLUSIONS: PSI predicts poor prognosis in NPC. Survival is poorer in patients with BPMI than in those with simple PMI. NPC with PSI should be classified as T4 stage.
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Neoplasias Nasofaríngeas , Radioterapia de Intensidad Modulada , Humanos , Imagen por Resonancia Magnética , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patología , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Pronóstico , Estudios RetrospectivosRESUMEN
PURPOSE: To assess the impact of tumor necrosis on treatment sensitivity and long-term survival in patients with nasopharyngeal carcinoma (NPC) treated using intensity-modulated radiation therapy (IMRT). PARTICIPANTS AND METHODS: In total, 757 patients with non-metastatic, histologically confirmed NPC were retrospectively examined. All patients were treated using IMRT; 93.7% patients with stage T3-T4/N1-N3 disease also received cisplatin-based chemotherapy. RESULTS: The incidence rates of tumor necrosis in primary tumor, retropharyngeal lymph nodes, neck lymph nodes, and total tumor were 2%, 17.7%, 21.5%, and 31.4%. Overall, 40.8% patients with necrosis of the total tumor achieved complete response (CR) and 54.7% patients without tumor necrosis achieved CR at the end of treatment (χ2 = 12.728, P < 0.001). The estimated 7-year overall survival (OS), failure-free survival (FFS), distant metastasis-free survival (DMFS), and loco-regional relapse-free survival (LRRFS) for patients with tumor necrosis and without tumor necrosis of the total tumor were 68.5% vs. 88.4%, 70.5% vs. 88.1%, 77.6% vs. 90.6%, and 85.9% vs. 91.3%, respectively (all P < 0.001). Multivariate analyses indicated that necrosis of the total tumor was an independent predictor of OS, FFS, DMFS, and LRRFS. The impact of lymph node necrosis on long-term survival was similar to that of necrosis of the total tumor. ROC curves verified that inclusion of lymph node necrosis improved the predictive value of the current N classification criteria (P = 0.006). CONCLUSIONS: Tumor necrosis served as a predictor of treatment sensitivity and poor prognosis for patients with NPC. Lymph node necrosis significantly improved the prognostic value of the current N classification criteria for NPC.
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Carcinoma , Neoplasias Nasofaríngeas , Radioterapia de Intensidad Modulada , Carcinoma/patología , Carcinoma/terapia , Supervivencia sin Enfermedad , Humanos , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/radioterapia , Necrosis , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Pronóstico , Estudios RetrospectivosRESUMEN
BACKGROUND: Radiotherapy plays a critical role in the management of non-small cell lung cancer (NSCLC). This study was conducted to identify gene expression profiles of acquired radioresistant NSCLC cell line established by fractionated ionizing radiation (FIR) by cDNA microarray. METHODS: The human lung adenocarcinoma cell line Anip973 was treated with high energy X-ray to receive 60 Gy in 4 Gy fractions. The radiosensitivity of Anip973R and its parental line were measured by clonogenic assay. Gene expression profiles of Anip973R and its parental line were analyzed using cDNA microarray consisting of 21 522 human genes. Identified partly different expressive genes were validated by quantitative reverse transcription-polymerase chain reaction (Q-RT-PCR). RESULTS: Fifty-nine upregulated and 43 downregulated genes were identified to radio-resistant Anip973R. Up-regulated genes were associated with DNA damage repair (DDB2), extracellular matrix (LOX), cell adhesion (CDH2), and apoptosis (CRYAB). Down-regulated genes were associated with angiogenesis (GBP-1), immune response (CD83), and calcium signaling pathway (TNNC1). Subsequent validation of selected eleven genes (CD24, DDB2, IGFBP3, LOX, CDH2, CRYAB, PROCR, ANXA1 DCN, GBP-1 and CD83) by Q-RT-PCR was consistent with microarray analysis. CONCLUSIONS: Fractionated ionizing radiation can lead to the development of radiation resistance. Altered gene profiles of radioresistant cell line may provide new insights into mechanisms underlying clinical radioresistance for NSCLC.
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Carcinoma de Pulmón de Células no Pequeñas/genética , Perfilación de la Expresión Génica , Neoplasias Pulmonares/genética , Tolerancia a Radiación , Adenocarcinoma/genética , Adenocarcinoma/radioterapia , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Línea Celular Tumoral/efectos de la radiación , Fraccionamiento de la Dosis de Radiación , Relación Dosis-Respuesta en la Radiación , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/radioterapia , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
OBJECTIVE: The purpose of the present study was to explore the relationship between the expression of S100A4 and E-cad protein and some clinicopathological factors such as histological types, TNM stages, lymph node metastasis and prognosis in non-small cell lung cancer (NSCLC), and analyze whether there is a correlation between them. METHODS: The expression of S100A4 protein and E-cad protein was detected with immunohistochemical SP technique in 116 non-small-cell lung cancers. RESULTS: The positive immunohistochemical staining for S100A4 protein was observed in 64 out of the 116 patients, with a positive rate of 55.2%. The expression rate of S100A4 protein was associated with age, tumor size, lymph node metastasis and prognosis of NSCLC. The expression of S100A4 protein was not significantly related with histological types, sex and TNM stages. The positive rate of E-cad protein expression was 65.5%. The expression of E-cad protein was associated with TNM staging, lymph node metastasis and prognosis of NSCLC. The expression of E-cad protein had no significant correlation with histological types, patient age and sex. An inverse correlation between the levels of S100A4 and E-cad protein expression was found (P < 0.005). CONCLUSION: Expression of S100A4 protein and loss of E-cad protein expression are significantly associated with tumor progression, and may become valuable markers in prediction of biological behavior and tendency of metastasis of non-small-cell lung cancers.
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Cadherinas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas S100/metabolismo , Biomarcadores de Tumor , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Proteína de Unión al Calcio S100A4 , Tasa de SupervivenciaRESUMEN
Nucleolin (C23) is an important anti-apoptotic protein that is ubiquitously expressed in exponentially growing eukaryotic cells. In order to understand the impact of C23 in radiation therapy, we attempted to investigate the relationship of C23 expression with the radiosensitivity of human non-small cell lung cancer (NSCLC) cells. We investigated the role of C23 in activating the catalytic subunit of DNA-dependent protein kinase (DNA- PKcs), which is a critical protein for DNA double-strand breaks (DSBs) repair. As a result, we found that the expression of C23 was negatively correlated with the radiosensitivity of NSCLC cell lines. In vitro clonogenic survival assays revealed that C23 knockdown increased the radiosensitivity of a human lung adenocarcinoma cell line, potentially through the promotion of radiation-induced apoptosis and adjusting the cell cycle to a more radiosensitive stage. Immunofluorescence data revealed an increasing quantity of γ-H2AX foci and decreasing radiation-induced DNA damage repair following knockdown of C23. To further clarify the mechanism of C23 in DNA DSBs repair, we detected the expression of DNA-PKcs and C23 proteins in NSCLC cell lines. C23 might participate in DNA DSBs repair for the reason that the expression of DNA-PKcs decreased at 30, 60, 120 and 360 minutes after irradiation in C23 knockdown cells. Especially, the activity of DNA-PKcs phosphorylation sites at the S2056 and T2609 was significantly suppressed. Therefore we concluded that C23 knockdown can inhibit DNA-PKcs phosphorylation activity at the S2056 and T2609 sites, thus reducing the radiation damage repair and increasing the radiosensitivity of NSCLC cells. Taken together, the inhibition of C23 expression was shown to increase the radiosensitivity of NSCLC cells, as implied by the relevance to the notably decreased DNA-PKcs phosphorylation activity at the S2056 and T2609 clusters. Further research on targeted C23 treatment may promote effectiveness of radiotherapy and provide new targets for NSCLC patients.
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Adenocarcinoma/genética , Carcinoma de Células Grandes/genética , Neoplasias Pulmonares/genética , Fosfoproteínas/genética , Proteínas de Unión al ARN/genética , Tolerancia a Radiación/genética , Apoptosis/genética , Apoptosis/efectos de la radiación , Carcinoma de Pulmón de Células no Pequeñas/genética , Línea Celular Tumoral , Proliferación Celular/genética , Proliferación Celular/efectos de la radiación , Supervivencia Celular/genética , Supervivencia Celular/efectos de la radiación , Roturas del ADN de Doble Cadena/efectos de la radiación , Reparación del ADN/genética , Reparación del ADN/efectos de la radiación , Proteína Quinasa Activada por ADN , Técnicas de Silenciamiento del Gen , Humanos , Proteínas Nucleares , Fosforilación , Interferencia de ARN , NucleolinaRESUMEN
BACKGROUND: Nimotuzumab is a humanized IgG1 monoclonal antibody specifically targeting EGFR. In this study, we aimed to investigate the molecular mechanisms of nimotuzumab in its effects of enhancing cancer cell radiosensitivity. PRINCIPAL FINDING: Lung cancer A549 cells and breast cancer MCF-7 cells were pretreated with or without nimotuzumab for 24 h before radiation to perform the clonogenic survival assay and to analyze the cell apoptosis by flow ctyometry. γ-H2AX foci were detected by confocal microscopy to assess the effect of nimotuzumab on radiation induced DNA repair. EGFR activation was examined and the levels of DNA damage repair related proteins in A549 cells at different time point and at varying doses exposure after nimotuzumab and radiation treatment were examined by Western blot. Pretreatment with nimotuzumab reduced clonogenic survival after radiation, inhibited radiation-induced EGFR activation and increased the radiation-induced apoptosis in both A549 cells and MCF-7 cells. The foci of γ-H2AX 24 h after radiation significantly increased in nimotuzumab pretreated cells with different doses. The phosphorylation of AKT and DNA-PKcs were remarkably inhibited in the combination group at each dose point as well as time point. CONCLUSIONS: Our results revealed that the possible mechanism of nimotuzumab enhancing the cancer radiosensitivity is that nimotuzumab inhibited the radiation-induced activation of DNA-PKcs through blocking the PI3K/AKT pathway, which ultimately affected the DNA DSBs repair.
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Anticuerpos Monoclonales Humanizados/farmacología , Apoptosis/efectos de los fármacos , Reparación del ADN/efectos de los fármacos , Tolerancia a Radiación/efectos de los fármacos , Apoptosis/efectos de la radiación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Daño del ADN , Reparación del ADN/efectos de la radiación , Proteína Quinasa Activada por ADN/antagonistas & inhibidores , Proteína Quinasa Activada por ADN/genética , Proteína Quinasa Activada por ADN/metabolismo , Relación Dosis-Respuesta a Droga , Receptores ErbB/agonistas , Receptores ErbB/genética , Receptores ErbB/metabolismo , Rayos gamma , Regulación de la Expresión Génica , Histonas/agonistas , Histonas/genética , Histonas/metabolismo , Humanos , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de SeñalRESUMEN
OBJECTIVE: To conduct a meta-analysis to investigate the value of EBV DNA in diagnosis of nasopharyngeal cancer (NPC) in Asian populations, and provide important evidence for screening. METHODS: Prospective or respective case-control or cohort studies regarding the detection role of EBV DNA for NPC were included in our study. We conducted a comprehensive literature search in PubMed, EMBASE, and the Chinese Biomedical Database (CBM database between January 1980 and March 2012. RESULTS: A total of 18 studies with 1492 NPC cases and 2641 health controls were included. Almost of the included studies were conducted in China, and only one other conducted in Thailand. The overall results demonstrated that the pooled sensitivity, specificity, positive likelihood (+ LR) and negative likelihood (-LR) were 0.73 (0.71-0.75), 0.89 (0.88-0.90), 8.84 (5.65-13.84) and 0.19(0.11-0.32), respectively. The overall EBV DNA detection showed the largest area of 0.932 under the summary receiver operator curve (SROC). The accuracy of detection by plasma for NPC (0.86) was higher than in serum (0.81), with largest areas under the SROC of 0.97 and 0.91, respectively. CONCLUSION: Our results demonstrated the EBV DNA detection in plasma or serum has high sensitivity and specificity in diagnosis of NPC, especially in Chinese populations with a high risk of cancer.
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ADN Viral/sangre , Infecciones por Virus de Epstein-Barr/diagnóstico , Herpesvirus Humano 4/aislamiento & purificación , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/virología , Antígenos Virales/inmunología , Carcinoma , Estudios de Casos y Controles , China , Estudios de Cohortes , Infecciones por Virus de Epstein-Barr/virología , Herpesvirus Humano 4/genética , Humanos , Tamizaje Masivo , Carcinoma Nasofaríngeo , Estudios Prospectivos , TailandiaRESUMEN
The relationship between IL-17A and cancer, whether beneficial or antagonistic, continues to be a controversial issue. In this study, effects of IL-17A on lung adenocarcinoma were investigated using lung cancer cell lines, 95D and 95C. In the presence or absence of IL-17A, cell proliferation and VEGF secretion were detected. Effects of IL-17A on capillary networks and process of angiogenesis were also evaluated. In vivo, the level of IL-17A was assayed in the serum of lung adenocarcinoma patients. At the same time, slices of adenocarcinoma tissue were analyzed for expression of IL-17A, its receptor (IL-17RA), VEGF, CD4(+)-IL-17A+ cells and CD8(+)-IL-17A+ cells by immunohistochemistry and immunofluorescence assays. IL-17A did not have effect on the proliferation of 95D or 95C cells, however, the elevated expression of VEGF in supernatant of 95D or 95C cells was found to be IL-17A concentration-dependent. Supernatants from 95D or 95C cells treated with IL-17A could obviously facilitate angiogenesis, compared with IL-17A absence group (P < 0.01). Higher levels of IL-17A were detected in serum of patients with lung adenocarcinoma than healthy controls (P < 0.001). Higher positive expressions of IL-17A, IL-17RA and VEGF were confirmed in lung adenocarcinoma lesion tissues compared to pericancerous normal tissues (P < 0.001). Tnc17 cells, as well as Th17 cells were found in adenocarcinoma tissue, indicating a potential role of these cells in disease. In summary, IL-17A might affect lung adenocarcinoma by promoting angiogenesis, while the role of Tnc17 cells or Th17 cells remains to be elucidated.