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Inside hippocampal circuits, neuroplasticity events that individual cells may undergo during synaptic transmissions occur in the form of Long-Term Potentiation (LTP) and Long-Term Depression (LTD). The high density of NMDA receptors expressed on the surface of the dendritic CA1 spines confers to hippocampal CA3-CA1 synapses the ability to easily undergo NMDA-mediated LTP and LTD, which is essential for some forms of explicit learning in mammals. Providing a comprehensive kinetic model that can be used for running computer simulations of the synaptic transmission process is currently a major challenge. Here, we propose a compartmentalized kinetic model for CA3-CA1 synaptic transmission. Our major goal was to tune our model in order to predict the functional impact caused by disease associated variants of NMDA receptors related to severe cognitive impairment. Indeed, for variants Glu413Gly and Cys461Phe, our model predicts negative shifts in the glutamate affinity and changes in the kinetic behavior, consistent with experimental data. These results point to the predictive power of this multiscale viewpoint, which aims to integrate the quantitative kinetic description of large interaction networks typical of system biology approaches with a focus on the quality of a few, key, molecular interactions typical of structural biology ones.
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Región CA1 Hipocampal/metabolismo , Modelos Biológicos , Receptores AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapsis/metabolismo , Transmisión Sináptica , Algoritmos , Relación Dosis-Respuesta a Droga , Glutamatos/metabolismo , Glutamatos/farmacología , Simulación de Dinámica Molecular , Mutación , Plasticidad Neuronal/fisiología , Conformación Proteica , Células Piramidales/metabolismo , Receptores AMPA/química , Receptores AMPA/genética , Receptores de Glutamato/metabolismo , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/genética , Relación Estructura-Actividad , Potenciales SinápticosRESUMEN
Background: The Anaplastic Lymphoma Kinase (ALK) gene is known to be affected by several genetic alterations, such as rearrangement, amplification and point mutation. The main goal of this study was to comprehensively analyze ALK amplification (ALK-A) and ALK gene copy number gain (ALK-CNG) in a large cohort of non-small-cell lung cancer (NSCLC) patients in order to evaluate the effects on mRNA and protein expression. Methods: ALK locus number status was evaluated in 578 NSCLC cases by fluorescence in situ hybridization (FISH). In addition, ALK immunohistochemistry and ALK mRNA in situ hybridization were performed. Results: Out of 578 cases, 17 cases showed ALK-A. In addition, 14 cases presented ALK-CNG and 72 cases presented chromosome 2 polyploidy. None of those carrying ALK-A and -CNG showed either ALK immunohistochemical expression or ALK mRNA expression through in situ hybridization. We observed a high frequency of extra copies of the ALK gene. Conclusions: Our findings demonstrated that ALK-A is not involved in mRNA production and consequently is not involved in protein production; these findings support the hypothesis that ALK-A might not play a role in the pathogenesis of NSCLC, underlining the absence of a specific clinical application.
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Quinasa de Linfoma Anaplásico/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Amplificación de Genes , Dosificación de Gen , Neoplasias Pulmonares/genética , Proteínas de Neoplasias/genética , Anciano , Cromosomas Humanos Par 2/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Hibridación in Situ , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Poliploidía , ARN Mensajero/biosíntesis , ARN Mensajero/genética , ARN Neoplásico/biosíntesis , ARN Neoplásico/genéticaRESUMEN
pRb2/p130 is a key tumor suppressor, whose oncosuppressive activity has mainly been attributed to its ability to negatively regulate cell cycle by interacting with the E2F4 and E2F5 transcription factors. Indeed, pRb2/p130 has been found altered in various cancer types in which it functions as a valuable prognostic marker. Here, we analyzed pRb2/p130 expression in gastric cancer tissue samples of diffuse histotype, in comparison with their normal counterparts. We found a cytoplasmic localization of pRb2/p130 in cancer tissue samples, whereas, in normal counterparts, we observed the expected nuclear localization. pRb2/p130 cytoplasmic delocalization can lead to cell cycle deregulation, but considering the emerging involvement of pRb2/p130 in other key cellular processes, it could contribute to gastric tumorigenesis also through other mechanisms. Our data support the necessity of further investigations to verify the possibility of using pRb2/p130 as a biomarker or potential therapeutic target for diffuse gastric cancer.
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Proteína Sustrato Asociada a CrK/metabolismo , Citoplasma/metabolismo , Proteínas Salivales Ricas en Prolina/metabolismo , Neoplasias Gástricas/metabolismo , Factores de Transcripción/metabolismo , Proteínas de Ciclo Celular/metabolismo , División Celular/genética , División Celular/fisiología , Femenino , Genes Supresores de Tumor/fisiología , Humanos , Masculino , Fosfoproteínas/fisiología , Proteína de Retinoblastoma/metabolismo , Proteína p130 Similar a la del Retinoblastoma/metabolismo , Neoplasias Gástricas/genéticaRESUMEN
BACKGROUND: Immune-checkpoint inhibitors (ICIs) represent an important treatment option for patients who have advanced stage non-small cell lung cancer (NSCLC). Currently, evaluation of the expression level of programmed death-ligand 1 (PD-L1) has proven highly successful as a positive predictive biomarker for ICIs. In addition to PD-L1, other promising predictive biomarkers are emerging, including high tumor mutational burden (TMB-H). However, measuring TMB-H remains challenging for several reasons, among which is the difficulty in obtaining adequate tissue material from NSCLC patients. There are no data in the current literature regarding the possibility of adopting cell blocks (CBs) for TMB evaluation; therefore, our goal was to evaluate the feasibility of analyzing TMB on CBs. METHODS: For evaluation of differences in run metric parameters, 8 pairs of histological and CB samples from patients with NSCLC were analyzed using the Oncomine Tumor Mutational Load Assay on Ion Torrent S5 GS next-generation sequencing (NGS) platform. RESULTS: Most CBs (6/8, 75.0%) were successfully analyzed by adopting the broad NGS panel approach. CBs provided results similar to those obtained on histological matched specimens in terms of median total reads (7207048.80 vs 7558817.80), median mapped reads (7075753.83 vs 7513822.00), median read lengths (115.50 vs. 113.00), median percentage of reads on-target (97.49% vs. 98.45%), median average reads per amplicon (454.67 vs 476.14), and median uniformity of amplicon coverage (83.52% vs 84.13%). CONCLUSION: In this pilot study, we demonstrated the technical feasibility of assessing TMB on CBs.
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Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Técnicas Citológicas/métodos , Análisis Mutacional de ADN/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Neoplasias Pulmonares/genética , Mutación , Anciano , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/patología , Masculino , Proyectos Piloto , Pronóstico , Estudios RetrospectivosRESUMEN
Immune checkpoint inhibitors against programmed cell death protein 1/programmed death-ligand 1 (PD-L1) have proven to be remarkably effective in non-small cell lung cancer. PD-L1 represents a predictive biomarker in lung cancer, although its heterogenous expression represents an emerging challenge for accurate biomarker-based patient selection. Lung adenocarcinomas (ADCs) show a high rate of intratumor morphologic heterogeneity that may reflect a heterogenous molecular and immunophenotypic profile. The aim of our study was to analyze the expression of PD-L1 in different intratumor subtypes and/or growth patterns in a series of mixed adenocarcinomas (mADCs) and adenosquamous lung carcinomas (AdSqLCs). As many as 73 mADCs and 6 AdSqLCs were selected. Comprehensive histologic subtyping was performed, and PD-L1 expression was assessed by immunohistochemistry assay using different primary antibodies and automated immunostainers. Overall, PD-L1 expression was observed in 37 of 79 cases (39.2%) (31 mADCs and all AdSqLCs). PD-L1 expression was heterogenous in 22 of 37 PD-L1-positive cases (23.2% mADC and 83% AdSqLC). PD-L1 expression was observed more frequently in ADC with solid pattern. Heterogeneity of PD-L1 expression was significantly related to the presence of micropapillary (P=0.028) and solid (P=0.017) patterns. All PD-L1-positive cases were epidermal growth factor receptor wild-type, 2 cases harbored concomitantly PD-L1 expression and ALK rearrangement. Our data suggest that PD-L1 expression is quite heterogenous in mADCs and AdSqLCs, partly contributing to explaining the discrepant results between biopsy and surgical resections and discordant clinical effectiveness in regard to PD-L1-positive or negative ADC diagnosed on cytology/small biopsy.
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Adenocarcinoma/metabolismo , Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinoma Adenoescamoso/metabolismo , Neoplasias Pulmonares/metabolismo , Adenocarcinoma/diagnóstico , Adenocarcinoma/patología , Anciano , Anciano de 80 o más Años , Biopsia , Carcinoma Adenoescamoso/diagnóstico , Carcinoma Adenoescamoso/patología , Femenino , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana EdadRESUMEN
AIM: To evaluate whether a dose of 50 mg preserved the architecture of the corpora cavernosa biopsy in man. METHODS: 21 patients (54-70 years old) who underwent radical prostatectomy for prostate cancer were treated with sildenafil citrate (50 mg, 3 times a week for 2 months) soon after surgery. They underwent cavernous biopsy before surgery and after 2 months of sildenafil treatment. Biopsy tissues were fixed in formalin, stained with Masson's trichrome method, and evaluated with the Eureka Interface system with a per-area analysis, and elastic fibers were counted on 10-12 fields (x400) of five serial sections. RESULTS: Two months after surgery the percent of connective tissue in cavernosa samples in all patients did not differ from that before surgery, being between 30 and 40% in the per-area analysis. Similarly, the elastic fiber count did not differ significantly before and after surgery. CONCLUSIONS: Sildenafil prevented the progression of fibrosis in prostatectomized patients. Its efficacy seems to result from an antiproliferative effect exerted on fibroblasts.
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Enfermedades del Pene/patología , Enfermedades del Pene/prevención & control , Pene/patología , Piperazinas/uso terapéutico , Prostatectomía/efectos adversos , Sulfonas/uso terapéutico , Anciano , Fibrosis/etiología , Fibrosis/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Pene/etiología , Piperazinas/administración & dosificación , Purinas/administración & dosificación , Purinas/uso terapéutico , Citrato de Sildenafil , Sulfonas/administración & dosificaciónRESUMEN
[This corrects the article DOI: 10.18632/oncotarget.25049.].
RESUMEN
Late diagnosis limits therapeutic options and survival rate of non-small cell lung cancer (NSCLC) patients. Therefore the identification of biomarkers represents an emerging medical need. A highly sensitive and specific test was developed to identify/quantify a novel/selective diagnostic biomarker for NSCLC patients, caspase-4. This test was validated by using i) plasma from 125 NSCLC patients and 79 healthy (non-pathological) subjects, ii) plasma from 139 smokers and iii) from 70 chronic-obstructive pulmonary disease (COPD) patients. Caspase-4 quantification was also assessed in the lung tumor mass of 98 paired NSCLC patients compared to 10 non-tumor lung tissues (i.e. tuberculosis). Circulating caspase-4 was detected in both healthy and NSCLC patients; however at different range values: 2.603-3.372 ng/ml for NSCLC patients (95% CI) compared to 0.3994-0.6219 ng/ml for healthy subjects (95% CI). The sensitivity of the test ranged from 97.07% to 100%; the specificity was 88.1% with a positive predictive value of 92.54%, accuracy of 95.19% and AUC of 0.971. Smokers (95% CI, 0.3947-0.6197 ng/ml) and COPD patients (95% CI, 1.703-2.995 ng/ml) showed intermediate values of circulating caspase-4. Tissue levels of caspase-4 in the tumor mass showed that 72 (72.7%) out of 99 patients were positive. More importantly, higher levels (cut-off value = 0.307 ng/ml) of caspase-4 in the tumor mass were associated to reduced overall survival (median 0.92 years) compared to NSCLC patients with lower levels (median 3.02 years). We report for the first time caspase-4 as a novel diagnostic and prognostic biomarker, opening new therapeutic perspectives for NSCLC patients.
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Cyclooxygenases (COXs) are enzymes catalysing prostaglandin synthesis and are implicated in the carcinogenesis of some cancer types. In addition, an important role of these enzymes in herpesvirus infections was demonstrated and it has recently been proposed that COX-2 may participate in herpesvirus-induced neoplasia such as Kaposi's sarcoma (KS). To date no immunohistochemical study has been performed to determine the identification of COX-1 and COX-2 in KS. We have investigated 35 cases of classic KS and 27 cases of epidemic KS form in order to study the distribution and localisation of COXs. We have examined by immunohistochemistry the expression of COX-1 and COX-2 in classic and epidemic forms of KS also in relationship to the characteristic morphological phases (patch, plaque and nodular stage) of KS and cell localisation by double immunostaining. Moreover, we have obtained COX-1 and COX-2 expression by Western blot analysis. Our results establish that (a) COX-1 and COX-2 are overexpressed significantly in classic and epidemic KS compared with control skin tissues (P<0.01 and P>0.03, respectively, for COX-1; P<0.01 and P>0.03, respectively, for COX-2); (b) the extent and intensity staining for both COXs were higher in classic than in epidemic form of KS. Our data support the hypothesis that both COXs may be involved in the pathogenesis of KS.
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Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/metabolismo , Proteínas de Neoplasias/metabolismo , Sarcoma de Kaposi/enzimología , Western Blotting , Humanos , InmunohistoquímicaRESUMEN
The involvement of bronchial vasculature in the airway remodelling occurring in symptomatic smokers with normal lung function and with chronic obstructive pulmonary disease (COPD) has been poorly investigated. An immunohistochemical study was performed on bronchial biopsies taken from 8 non-smokers and 18 smokers divided, according to global health initiative on obstructive lung diseases (GOLD) classification of COPD, into two groups, GOLD 0 and GOLD 2, each of 9 subjects. The number of vessels and the percentage of vascular area in the lamina propria were evaluated by mAb anti-collagen IV. Cellular expression of VEGF and vascular expression of alphavbeta3 integrin were evaluated by the specific monoclonal antibodies. An image processing and analysis system was used to quantify the immunohistochemical data. The number of vessels, the vascular area, the cellular expression of VEGF, the number and percentage of alphavbeta3 positive vessels were significantly higher in GOLD 0 and in GOLD 2 smokers than in non-smokers. The comparison between GOLD 0 and GOLD 2 smokers did show a weak but significantly lower number of vessels in GOLD 2, while the vascular area and the percentage of alphavbeta3 positive vessels did not differ between the two groups. A higher cellular VEGF expression was detected in the GOLD 2 than in the GOLD 0 group. Angiogenesis of bronchial vessels is a component of the airway remodelling occurring in symptomatic smokers with normal lung function and with COPD, it seems independent by the development of airway obstruction and not related to its severity.
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Bronquios/patología , Neovascularización Patológica/patología , Enfermedad Pulmonar Obstructiva Crónica/patología , Mucosa Respiratoria/patología , Fumar/patología , Biopsia , Bronquios/irrigación sanguínea , Bronquios/metabolismo , Femenino , Volumen Espiratorio Forzado , Humanos , Integrina alfaVbeta3/metabolismo , Masculino , Persona de Mediana Edad , Neovascularización Patológica/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Mucosa Respiratoria/metabolismo , Fumar/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Capacidad VitalRESUMEN
BACKGROUND: In the cetuximab after progression in KRAS wild-type colorectal cancer patients (CAPRI) trial patients with metastatic colorectal cancer (mCRC) received 5-fluorouracil, folinic acid and irinotecan (FOLFIRI) and cetuximab in first line followed by 5-Fluorouracil, folinic acid, oxaliplatin (FOLFOX) with or without cetuximab until progression. Limited data are available on the efficacy and safety of anti-epidermal growth factor receptor (anti-EGFR) agents on elderly patients with mCRC. In the current study we evaluated the efficacy and safety of FOLFIRI plus cetuximab in age-defined subgroups. METHODS: A post-hoc analysis was performed in CAPRI trial patients; outcomes (progression-free survival (PFS), overall response rate (ORR), safety) were analysed by age-groups and stratified according to molecular characterisation. 3 age cut-offs were used to define the elderly population (≥65; ≥70 and ≥75â years). RESULTS: 340 patients with mCRC were treated in first line with FOLFIRI plus cetuximab. Among those, 154 patients were >65â years, 86 >70â years and 35 >75â years. Next-generation sequencing (NGS) was performed in 182 patients. Among them, 87 patients were >65â years, 46 >70 and 17 >75. 104 of 182 patients were wild type (WT) for KRAS, NRAS, BRAF, PIK3CA genes. In the quadruple WT group, 51 patients were ≥65â years; 29 were ≥70; 9 were ≥75. Median PFS was similar within the age-subgroups in the intention-to-treat population, NGS cohort and quadruple WT patients, respectively. Likewise, ORR was not significantly different among age-subgroups in the 3 populations. Safety profile was acceptable and similarly reported among all age-groups, with the exception of grade ≥3 diarrhoea (55% vs 25%, p=0.04) and neutropaenia (75% vs 37%, p=0.03) in patients ≥75â years and grade ≥3 fatigue (31% vs 20%, p=0.01) in patients <75â years. CONCLUSIONS: Tolerability of cetuximab plus FOLFIRI was acceptable in elderly patients. Similar ORR and PFS were observed according to age-groups. No differences in adverse events were reported among the defined subgroups with the exception of higher incidence of grade ≥3 diarrhoea and neutropaenia in patients ≥75â years and grade ≥3 fatigue in patients <75â years. TRIAL REGISTRATION NUMBER: 2009-014041-81.
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BACKGROUND: Epidermal growth factor receptor (EGFR) mutations are reliably detected by referral laboratories, even if most lung cancer cytology specimens sent to such laboratories contain very few cells. However, EGFR mutations may be distributed heterogeneously within tumors, thereby raising concerns that mutations detected on cytology are not representative of the entire tumor and, thus, are less reliable in predicting response to tyrosine kinase inhibitor (TKI) treatment than mutations detected on histology. To address this issue, the authors reviewed their clinical practice archives and compared the outcome of TKI treatment among patients who were selected by cytology versus patients who were selected by histology. METHODS: From July 2010 to July 2012, 364 cytology samples and 318 histology samples were received. Exon 19 deletions and the L858R point mutation in exon 21, detected by fragment assay and TaqMan assay, respectively, were confirmed by direct sequencing; discrepancies were resolved by cloning polymerase chain reaction products. The response rate (RR) and progression-free survival (PFS) at 12 months (range, 3-34 months) were evaluable in 13 EGFR-mutated patients who were selected for treatment by cytology and 13 patients who were selected by histology. RESULTS: The mutation rate was similar in histology samples (8.5%) and cytology samples (8.8%). The RR (54%) and PFS (9.2 months) were similar in histologically selected patients and cytologically selected patients (RR, 62%; PFS, 8.6 months; P = .88). The disease control rate (responsive plus stable disease) was 92% in histologically selected patients and 100% in cytologically selected patients. CONCLUSIONS: EGFR mutations detected on cytology specimens by a centralized laboratory can predict TKI treatment response equally well as mutations identified on histology samples.
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Carcinoma de Pulmón de Células no Pequeñas/genética , Citodiagnóstico , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Mutación/genética , Quinazolinas/uso terapéutico , Adenocarcinoma/genética , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Femenino , Gefitinib , Genotipo , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa , Pronóstico , Inhibidores de Proteínas Quinasas/uso terapéutico , Tasa de SupervivenciaRESUMEN
BACKGROUND/AIMS: Liver iron deposits are frequent in patients with non-alcoholic steato-hepatitis (NAFLD), but their role is not well defined. To investigate the effect of liver iron excess on the prevalence of hepatocellular carcinoma (HCC) in patients with NASH-related cirrhosis. METHODS: Hepatic iron was measured retrospectively with a semiquantitative method in liver biopsies of 153 patients with NASH-related cirrhosis: 51 with HCC and 102 controls without HCC, matched for age, sex and stage of liver disease. The corrected total iron score (0-60) was the sum of three scores: the hepatocytic iron score (0-36), sinusoidal iron score (0-12), and portal iron score (0-12), multiplied by 3/3, 2/3, or 1/3 depending on the localisation of the iron in the nodules. RESULTS: Conditional logistic regression analysis showed that iron deposits (corrected total iron score>0) were more frequent in HCC patients than in controls. The median corrected total iron score was significantly higher in HCC patients than in controls. The liver iron overload was sinusoidal. CONCLUSIONS: Iron deposition in the liver was more frequent in patients with NASH-related cirrhosis with HCC than in HCC-free controls. Liver iron overload may be associated with development of HCC in patients with NASH-related cirrhosis.
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Carcinoma Hepatocelular/metabolismo , Hígado Graso/complicaciones , Hierro/metabolismo , Neoplasias Hepáticas/metabolismo , Hígado/metabolismo , Carcinoma Hepatocelular/etiología , Hígado Graso/metabolismo , Femenino , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/metabolismo , Neoplasias Hepáticas/etiología , Masculino , Persona de Mediana EdadRESUMEN
CDK9 is a member of the CDC2-like family of kinases. Its cyclin partners are members of the CYCLIN T family (T1, T2a, and T2b) and CYCLIN K. The CDK9/CYCLIN T1 complex is very important in the differentiation programme of several cell types, controlling specific differentiation pathways. Limited data are available regarding the expression of CDK9/CYCLIN T1 in haematopoietic and lymphoid tissues. The aim of this study was to analyse the expression of the CDK9/CYCLIN T1 complex in lymphoid tissue, in order to assess its role in B- and T-cell differentiation and lymphomagenesis. CDK9/CYCLIN T1 expression was found by immunohistochemistry in precursor B and T cells. In peripheral lymphoid tissues, germinal centre cells and scattered B- and T-cell blasts in interfollicular areas expressed CDK9/CYCLIN T1, while mantle cells, plasma cells, and small resting T-lymphocytes displayed no expression of either molecule. CDK9/CYCLIN T1 expression therefore appears to be related to particular stages of lymphoid differentiation/activation. CDK9 and CYCLIN T1 were highly expressed in lymphomas derived from precursor B and T cells, from germinal centre cells, such as follicular lymphomas, and from activated T cells (ie anaplastic large cell lymphomas). Hodgkin and Reed-Sternberg cells of classical Hodgkin's lymphoma also showed strong nuclear staining. Diffuse large B-cell, Burkitt's lymphomas, and peripheral T-cell lymphomas, among T-cell lymphoproliferative disorders, showed a wide range of values. No expression of CDK9 or CYCLIN T1 was detected in mantle cell and marginal zone lymphomas. However, at the mRNA level, an imbalance in the CDK9/CYCLIN T1 ratio was found in follicular lymphoma and diffuse large B-cell lymphomas with germinal centre phenotype, and in the cell lines of classical Hodgkin's lymphomas, Burkitt's lymphomas, and anaplastic large cell lymphoma, in comparison with reactive lymph nodes. These results suggest that the CDK9/CYCLIN T1 complex may affect the activation and differentiation programme of lymphoid cells. The molecular mechanism through which the CDK9/CYCLIN T1 complex is altered in malignant transformation needs to be elucidated.