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2.
ESMO Open ; 6(5): 100273, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34607285

RESUMEN

BACKGROUND: To further characterize survival benefit with first-line nivolumab plus ipilimumab with two cycles of chemotherapy versus chemotherapy alone, we report updated data from the phase III CheckMate 9LA trial with a 2-year minimum follow-up. PATIENTS AND METHODS: Adult patients were treatment naïve, with stage IV/recurrent non-small-cell lung cancer, no known sensitizing EGFR/ALK alterations, and an Eastern Cooperative Oncology Group performance status ≤1. Patients were randomized 1 : 1 to nivolumab 360 mg every 3 weeks plus ipilimumab 1 mg/kg every 6 weeks with two cycles of chemotherapy, or four cycles of chemotherapy. Updated efficacy and safety outcomes are reported, along with progression-free survival (PFS) after next line of treatment (PFS2), treatment-related adverse events (TRAEs) by treatment cycle, and efficacy outcomes in patients who discontinued all treatment components in the experimental arm due to TRAEs. RESULTS: With a median follow-up of 30.7 months, nivolumab plus ipilimumab with chemotherapy continued to prolong overall survival (OS) versus chemotherapy. Median OS was 15.8 versus 11.0 months [hazard ratio 0.72 (95% confidence interval 0.61-0.86)]; 2-year OS rate was 38% versus 26%. Two-year PFS rate was 20% versus 8%. ORR was 38% versus 25%, respectively; 34% versus 12% of all responses were ongoing at 2 years. Median PFS2 was 13.9 versus 8.7 months. Improved efficacy outcomes in the experimental versus control arm were observed across most subgroups, including by programmed death-ligand 1 and histology. No new safety signals were observed; onset of grade 3/4 TRAEs was mostly observed during the first two treatment cycles in the experimental arm. In patients who discontinued all components of nivolumab plus ipilimumab with chemotherapy treatment due to TRAEs (n = 61) median OS was 27.5 months; 56% of responders had an ongoing response ≥1 year after discontinuation. CONCLUSIONS: With a 2-year minimum follow-up, nivolumab plus ipilimumab with two cycles of chemotherapy provided durable efficacy benefits over chemotherapy with a manageable safety profile and remains an efficacious first-line treatment of advanced non-small-cell lung cancer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Humanos , Ipilimumab/efectos adversos , Neoplasias Pulmonares/tratamiento farmacológico , Recurrencia Local de Neoplasia , Nivolumab/efectos adversos
3.
Front Pharmacol ; 12: 652074, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34295245

RESUMEN

Cancer is a devastating disease and has recently become the leading cause of death in western countries, representing an immense public health burden. When it comes to cancer treatment, chemotherapy is one of the main pillars, especially for advanced stage tumors. Over the years, natural compounds have emerged as one of the most valuable resources for new chemotherapies. It is estimated that more than half of the currently used chemotherapeutic agents are derived from natural compounds. Usually, natural compounds are discovered empirically and an important limitation of introducing new anti-cancer natural products is lack of knowledge with regard to their mechanism of action. Recent data has proven that several natural compounds may function via modulating the expression and function of non-coding RNAs (ncRNAs). NcRNAs are a heterogenous class of RNA molecules which are usually not translated into proteins but have an important role in gene expression regulation and are involved in multiple tumorigenic processes, including response/resistance to pharmacotherapy. In this review, we will discuss how natural compounds function via ncRNAs while summarizing the available data regarding their effects on over 15 types of cancer. Moreover, we will critically analyze the current advances and limitations in understanding the way natural compounds exert these health-promoting effects by acting on ncRNAs. Finally, we will propose several hypotheses that may open new avenues and perspectives regarding the interaction between natural compounds and ncRNAs, which could lead to improved natural compound-based therapeutic strategies in cancer.

4.
Front Chem ; 9: 690781, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34095091

RESUMEN

Biomolecules readily and irreversibly bind to plasma deposited Polyoxazoline thin films in physiological conditions. The unique reactivity of these thin films toward antibodies is driving the development of immunosensing platforms for applications in cancer diagnostics. However, in order for these coatings to be used as advanced immunosensors, they need to be incorporated into microfluidic devices that are sealed via plasma bonding. In this work, the thickness, chemistry and reactivity of the polyoxazoline films were assessed following plasma activation. Films deposited from methyl and isopropenyl oxazoline precursors were integrated into spiral microfluidic devices and biofunctionalized with prostate cancer specific antibodies. Using microbeads as model particles, the design of the spiral microfluidic was optimised to enable the size-based isolation of cancer cells. The device was tested with a mixed cell suspension of healthy and malignant prostate cells. The results showed that, following size-specific separation in the spiral, selective capture was achieved on the immunofunctionalised PPOx surface. This proof of concept study demonstrates that plasma deposited polyoxazoline can be used for immunosensing in plasma bonded microfluidic devices.

5.
Sci Rep ; 11(1): 10400, 2021 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-34002008

RESUMEN

The lateral hypothalamus (LH) is critically involved in the regulation of homeostatic energy balance. Some neurons in the LH express receptors for leptin (LepRb), a hormone known to increase energy expenditure and decrease energy intake. However, the neuroanatomical inputs to LepRb-expressing LH neurons remain unknown. We used rabies virus tracing technology to map these inputs, but encountered non-specific tracing. To optimize this technology for a minor cell population (LepRb is not ubiquitously expressed in LH), we used LepRb-Cre mice and assessed how different titers of the avian tumor virus receptor A (TVA) helper virus affected rabies tracing efficiency and specificity. We found that rabies expression is dependent on TVA receptor expression, and that leakiness of TVA receptors is dependent on the titer of TVA virus used. We concluded that a titer of 1.0-3.0 × 107 genomic copies per µl of the TVA virus is optimal for rabies tracing. Next, we successfully applied modified rabies virus tracing technology to map inputs to LepRb-expressing LH neurons. We discovered that other neurons in the LH itself, the periventricular hypothalamic nucleus (Pe), the posterior hypothalamic nucleus (PH), the bed nucleus of the stria terminalis (BNST), and the paraventricular hypothalamic nucleus (PVN) are the most prominent input areas to LepRb-expressing LH neurons.


Asunto(s)
Conectoma/métodos , Hipotálamo/diagnóstico por imagen , Imagen Molecular/métodos , Neuronas/metabolismo , Receptores de Leptina/análisis , Animales , Proteínas Aviares/genética , Femenino , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Virus Helper/genética , Hipotálamo/citología , Hipotálamo/metabolismo , Masculino , Ratones , Ratones Transgénicos , Microscopía Fluorescente , Virus de la Rabia/genética , Receptores de Leptina/metabolismo , Receptores Virales/genética , Núcleos Septales/citología , Núcleos Septales/diagnóstico por imagen , Núcleos Septales/metabolismo , Técnicas Estereotáxicas
6.
Int J Mol Sci ; 22(2)2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33430133

RESUMEN

Currently, for seemingly every type of cancer, dysregulated levels of non-coding RNAs (ncRNAs) are reported and non-coding transcripts are expected to be the next class of diagnostic and therapeutic tools in oncology. Recently, alterations to the ncRNAs transcriptome have emerged as a novel hallmark of cancer. Historically, ncRNAs were characterized mainly as regulators and little attention was paid to the mechanisms that regulate them. The role of modifications, which can control the function of ncRNAs post-transcriptionally, only recently began to emerge. Typically, these modifications can be divided into reversible (i.e., chemical modifications: m5C, hm5C, m6A, m1A, and pseudouridine) and non-reversible (i.e., editing: ADAR dependent, APOBEC dependent and ADAR/APOBEC independent). The first research papers showed that levels of these modifications are altered in cancer and can be part of the tumorigenic process. Hence, the aim of this review paper is to describe the most common regulatory modifications (editing and chemical modifications) of the traditionally considered "non-functional" ncRNAs (i.e., microRNAs, long non-coding RNAs and circular RNAs) in the context of malignant disease. We consider that only by understanding this extra regulatory layer is it possible to translate the knowledge about ncRNAs and their modifications into clinical practice.


Asunto(s)
Neoplasias/genética , Edición de ARN/genética , ARN no Traducido/genética , Transcriptoma/genética , Carcinogénesis/genética , Humanos , Neoplasias/terapia , ARN no Traducido/uso terapéutico
7.
Elife ; 92020 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-32940600

RESUMEN

The insular cortex (IC) plays key roles in emotional and regulatory brain functions and is affected across psychiatric diseases. However, the brain-wide connections of the mouse IC have not been comprehensively mapped. Here, we traced the whole-brain inputs and outputs of the mouse IC across its rostro-caudal extent. We employed cell-type-specific monosynaptic rabies virus tracings to characterize afferent connections onto either excitatory or inhibitory IC neurons, and adeno-associated viral tracings to label excitatory efferent axons. While the connectivity between the IC and other cortical regions was highly bidirectional, the IC connectivity with subcortical structures was often unidirectional, revealing prominent cortical-to-subcortical or subcortical-to-cortical pathways. The posterior and medial IC exhibited resembling connectivity patterns, while the anterior IC connectivity was distinct, suggesting two major functional compartments. Our results provide insights into the anatomical architecture of the mouse IC and thus a structural basis to guide investigations into its complex functions.


Asunto(s)
Mapeo Encefálico , Corteza Cerebral/anatomía & histología , Ratones/anatomía & histología , Neuronas/citología , Animales , Femenino , Masculino
8.
Cancers (Basel) ; 12(6)2020 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-32527011

RESUMEN

Bladder cancer (BC) is the tenth most frequent cancer worldwide. Due to the need for recurrent cystoscopies and the lack of non-invasive biomarkers, BC is associated with a high management burden. In this respect, small non-coding RNAs (sncRNAs) have been investigated in urine as possible biomarkers for BC, but in plasma their potential has not yet been defined. The expression levels of sncRNAs contained in plasma extracellular vesicles (EVs) from 47 men with BC and 46 healthy controls were assessed by next-generation sequencing. The sncRNA profiles were compared with urinary profiles from the same subjects. miR-4508 resulted downregulated in plasma EVs of muscle-invasive BC patients, compared to controls (adj-p = 0.04). In World Health Organization (WHO) grade 3 (G3) BC, miR-126-3p was upregulated both in plasma EVs and urine, when compared to controls (for both, adj-p < 0.05). Interestingly, two sncRNAs were associated with the risk class: miR-4508 with a downward trend going from controls to high risk BC, and piR-hsa-5936 with an upward trend (adj-p = 0.04 and adj-p = 0.05, respectively). Additionally, BC cases with low expression of miR-185-5p and miR-106a-5p or high expression of miR-10b-5p showed shorter survival (adj-p = 0.0013, adj-p = 0.039 and adj-p = 0.047, respectively). SncRNAs from plasma EVs could be diagnostic biomarkers for BC, especially in advanced grade.

9.
Langenbecks Arch Surg ; 404(8): 945-958, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31641855

RESUMEN

BACKGROUND: Central pancreatectomy (CP) is the alternative to distal pancreatectomy (DP) for specific pathologies of the mid-pancreas. However, the benefits of CP over DP remain controversial. This study aims to compare the two procedures by conducting a meta-analysis of all published papers. METHODS: A systematic search of original studies comparing CP vs. DP was performed using PubMed, Scopus, and Cochrane Library databases up to June 2018. The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) checklist was followed. RESULTS: Twenty-one studies were included (596 patients with CP and 1070 patients with DP). Compared to DP, CP was associated with significantly higher rates of overall and severe morbidity (p < 0.0001), overall and clinically relevant pancreatic fistula (p < 0.0001), postoperative hemorrhage (p = 0.02), but with significantly lower incidences of new-onset (p < 0.0001) and worsening diabetes mellitus (p = 0.004). Furthermore, significantly longer length of hospital stay (p < 0.0001) was observed for CP patients. CONCLUSIONS: CP is superior to DP regarding the preservation of pancreatic functions, but at the expense of significantly higher complication rates and longer hospital stay. Proper selection of patients is of utmost importance to maximize the benefits and mitigate the risks of CP.


Asunto(s)
Laparoscopía/métodos , Técnicas de Abdomen Abierto/métodos , Páncreas/cirugía , Pancreatectomía/métodos , Neoplasias Pancreáticas/cirugía , Supervivencia sin Enfermedad , Femenino , Humanos , Laparoscopía/efectos adversos , Tiempo de Internación , Masculino , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Técnicas de Abdomen Abierto/efectos adversos , Tempo Operativo , Páncreas/anatomía & histología , Pancreatectomía/mortalidad , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Selección de Paciente , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/fisiopatología , Pronóstico , Medición de Riesgo , Análisis de Supervivencia
10.
J Exp Clin Cancer Res ; 38(1): 231, 2019 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-31142339

RESUMEN

BACKGROUND: Because of the complexity of the blood-brain barrier (BBB), brain tumors, especially the most common and aggressive primary malignant tumor type arising from the central nervous system (CNS), glioblastoma, remain an essential challenge regarding diagnostic and treatment. There are no approved circulating diagnostic or prognostic biomarkers, nor novel therapies like immune checkpoint inhibitors for glioblastoma, and chemotherapy brings only minimal survival benefits. The development of molecular biology led to the discovery of new potential diagnostic tools and therapeutic targets, offering the premise to detect patients at earlier stages and overcome the current poor prognosis. MAIN BODY: One potential diagnostic and therapeutic breakthrough might come from microRNAs (miRNAs). It is well-known that miRNAs play a role in the initiation and development of various types of cancer, including glioblastoma. The review aims to answer the following questions concerning the role of RNA theranostics for brain tumors: (1) which miRNAs are the best candidates to become early diagnostic and prognostic circulating biomarkers?; (2) how to deliver the therapeutic agents in the CNS to overcome the BBB?; (3) which are the best methods to restore/inhibit miRNAs? CONCLUSIONS: Because of the proven roles played by miRNAs in gliomagenesis and of their capacity to pass from the CNS tissue into the blood or cerebrospinal fluid (CSF), we propose miRNAs as ideal diagnostic and prognostic biomarkers. Moreover, recent advances in direct miRNA restoration (miRNA mimics) and miRNA inhibition therapy (antisense oligonucleotides, antagomirs, locked nucleic acid anti-miRNA, small molecule miRNA inhibitors) make miRNAs perfect candidates for entering clinical trials for glioblastoma treatment.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , MicroARNs/genética , Tratamiento con ARN de Interferencia , Animales , Barrera Hematoencefálica/metabolismo , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Transformación Celular Neoplásica/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Interferencia de ARN , Tratamiento con ARN de Interferencia/métodos , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología
11.
BMC Microbiol ; 13: 171, 2013 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-23879872

RESUMEN

BACKGROUND: Microcalorimetric bacterial growth studies have illustrated that thermograms differ significantly with both culture media and strain. The present contribution examines the possibility of discriminating between certain bacterial strains by microcalorimetry and the qualitative and quantitative contribution of the sample volume to the observed thermograms. Growth patterns of samples of Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) were analyzed. Certain features of the thermograms that may serve to distinguish between these bacterial strains were identified. RESULTS: The thermograms of the two bacterial strains with sample volumes ranging from 0.3 to 0.7 ml and same initial bacterial concentration were analyzed. Both strains exhibit a roughly 2-peak shape that differs by peak amplitude and position along the time scale. Seven parameters corresponding to the thermogram key points related to time and heat flow values were proposed and statistically analyzed. The most relevant parameters appear to be the time to reach a heat flow of 0.05 mW (1.67 ± 0.46 h in E. coli vs. 2.99 ± 0.53 h in S. aureus, p < 0.0001), the time to reach the first peak (3.84 ± 0.5 h vs. 5.17 ± 0.49 h, p < 0.0001) and the first peak value (0.19 ± 0.02 mW vs. 0.086 ± 0.012 mW, p < 0.0001). The statistical analysis on 4 parameters of volume-normalized heat flow thermograms showed that the time to reach a volume-normalized heat flow of 0.1 mW/ml (1.75 ± 0.37 h in E. coli vs. 2.87 ± 0.65 h in S. aureus, p < 0.005), the time to reach the first volume-normalized peak (3.78 ± 0.47 h vs. 5.12 ± 0.52 h, p < 0.0001) and the first volume-normalized peak value (0.35 ± 0.05 mW/ml vs. 0.181 ± 0.040 mW/ml, p < 0.0001) seem to be the most relevant. Peakfit® decomposition and analysis of the observed thermograms complements the statistical analysis via quantitative arguments, indicating that: (1) the first peak pertains to a faster, "dissolved oxygen" bacterial growth (where the dissolved oxygen in the initial suspension acts as a limiting factor); (2) the second peak indicates a slower "diffused oxygen" growth that involves transport of oxygen contained in the unfilled part of the microcalorimetric cell; (3) a strictly fermentative growth component may slightly contribute to the observed complex thermal signal. CONCLUSION: The investigated strains of Staphylococcus aureus and Escherichia coli display, under similar experimental conditions, distinct thermal growth patterns. The two strains can be easily differentiated using a selection of the proposed parameters. The presented Peakfit analysis of the complex thermal signal provides the necessary means for establishing the optimal growth conditions of various bacterial strains. These conditions are needed for the standardization of the isothermal microcalorimetry method in view of its further use in qualitative and quantitative estimation of bacterial growth.


Asunto(s)
Calorimetría/métodos , Escherichia coli/crecimiento & desarrollo , Staphylococcus aureus/crecimiento & desarrollo , Técnicas Bacteriológicas/métodos , Especificidad de la Especie
12.
J BUON ; 17(2): 317-22, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22740212

RESUMEN

PURPOSE: The impact of adjuvant chemotherapy (CT) in the management of radically resected stage IB non-small cell lung cancer (NSCLC) is highly debated. The aim of this study was to evaluate the outcome of this category of patients treated at our institution. METHODS: We retrospectively analysed the survival data of patients with pathologic stage IB NSCLC, who received at least 1 cycle of adjuvant CT. CT was planned to be platinum based and to be delivered for 6 cycles. RESULTS: One hundred and twelve consecutively treated patients were evaluated. PATIENT CHARACTERISTICS: median age 60 years, median tumor diameter 4 cm, 87% underwent lobectomy and 13% pneumonectomy, 58% had visceral pleural involvement (VPI). After a median follow up of 46 months, the estimated 5-year disease-free (DFS) and overall survival (OS) rates were 68% and 77%, respectively. The mean number of CT cycles was 5.2 (range 3-6), with 82% of patients receiving ≥ 5 cycles. The median cisplatin dose intensity (DI) was 22 mg/m(2)/week, and the relative DI was 85%. Median total cisplatin (CDDP) dose/patient was 416 mg/m(2). A total of 31 (27.6%) relapses were recorded, of which 81% were distant. Multivariate analysis showed no significant interaction between overall survival and the following variables: gender, type of surgery, histology, tumor volume, VPI. CONCLUSION: Our results compare favorably with the historical data evaluating the outcome of stage IB patients treated by surgery alone in a customary medical setting. Overall, our data support the use of adjuvant CT in stage IB NSCLC patients.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Carcinoma de Células Grandes/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Células Escamosas/tratamiento farmacológico , Cisplatino/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adulto , Anciano , Carcinoma de Células Grandes/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Células Escamosas/mortalidad , Quimioterapia Adyuvante , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia/mortalidad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
13.
Chirurgia (Bucur) ; 105(5): 637-43, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21141087

RESUMEN

Cutaneous melanoma is the most aggressive skin malignancies with increasing rate of incidence in the latest decades. New imaging technique plays an important role in melanoma management: dermoscopy and computer dermoscopy, ultrasound, MRI, CT, PET and PET/CT. Due to the dermoscopy and lesion diagnosis in early stages the increasing number of curative melanoma are registered. Sentinel lymph node biopsy became a compulsory phase for patients with tumor thickness > 1 mm. Serological biomarkers proved to be a necessary investigation for melanoma diagnosis, follow-up and treatment response. Current TNM melanoma staging is based on AJCC classification since 2001 witch includes new elements like histopathologic ulceration in stage I and II and lymph node micro- and macrometastases in stage III. Treatment protocols include surgical tumor excision with only 1-2 cm safety margins and radical lymphadenectomy is performed after positive sentinel lymph node biopsy. The adjuvant treatment in advanced stages including chemotherapy, unspecific immunotherapy and interferon offers poor results regarding free disease terms rate of survival. The advanced therapeutic procedure like golden nanospheres and gene therapy are recently studied and represent an alternative for future treatment of melanoma. Follow-up protocols have a great importance for detection of the melanoma recurrences and include clinical, serological and imaging evaluation. Despite all new knowledge and technological support the advanced stage melanoma management still remain an unsolved problem.


Asunto(s)
Melanoma/diagnóstico , Melanoma/terapia , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/terapia , Quimioterapia Adyuvante , Diagnóstico Diferencial , Detección Precoz del Cáncer , Humanos , Incidencia , Oncología Médica/tendencias , Melanoma/mortalidad , Estadificación de Neoplasias , Factores de Riesgo , Rumanía/epidemiología , Biopsia del Ganglio Linfático Centinela , Tasa de Supervivencia , Resultado del Tratamiento
14.
Biochemistry ; 49(41): 8944-54, 2010 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-20795716

RESUMEN

Actin filament subunit interfaces are required for the proper interaction between filamentous actin (F-actin) and actin binding proteins (ABPs). The production of small F-actin complexes mimicking such interfaces would be a significant advance toward understanding the atomic interactions between F-actin and its many binding partners. We produced actin lateral dimers and trimers derived from F-actin and rendered polymerization-deficient by ADP-ribosylation of Arg-177. The degree of modification resulted in a moderate reduction in thermal stability. Calculated hydrodynamic radii were comparable to theoretical values derived from recent models of F-actin. Filament capping capabilities were retained and yielded pointed-end dissociation constants similar those of wild-type actin, suggesting native or near-native interfaces on the oligomers. Changes in DNase I binding affinity under low and high ionic strength suggested a high degree of conformational flexibility in the dimer and trimer. Polymer nucleation activity was lost upon ADP-ribosylation and rescued upon enzyme-mediated deADP-ribosylation, or upon binding to gelsolin, suggesting that interactions with actin binding proteins can overcome the inhibiting activities of ADP-ribosylation. The combined strategy of chemical cross-linking and ADP-ribosylation provides a minimalistic and reversible approach to engineering polymerization-deficient F-actin oligomers that are able to act as F-actin binding protein scaffolds.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Adenosina Difosfato Ribosa/metabolismo , Multimerización de Proteína/fisiología , Citoesqueleto de Actina/química , Actinas/química , Adenosina Difosfato Ribosa/química , Animales , Bovinos , Pollos , Desoxirribonucleasa I/química , Desoxirribonucleasa I/metabolismo , Gelsolina/química , Gelsolina/metabolismo , Humanos , Unión Proteica , Estructura Cuaternaria de Proteína
15.
J BUON ; 14(3): 375-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19810126

RESUMEN

For decades tamoxifen (TAM) has been the mainstay hormonal treatment for estrogen receptor positive (ER+) breast cancer patients. Nevertheless, during the last years, for postmenopausal women particularly, the third generation aromatase inhibitors (AI) became the preferred alternative. The results of the randomized trials showed that AI were superior to TAM in terms of efficacy, and were accompanied by a different but fairly convenient side effects profile. Subsequently, all updated guidelines recommend the use of AI in the adjuvant setting for this category of patients, either upfront, following 2-3 years of TAM or as extended adjuvant therapy, after 5 years of TAM. However, no consensus has been reached regarding the best strategy to be used, and the expert opinion is divided, based on the available evidence. The controversial aspect of whether AI should be used upfront or following 2-3 years of TAM is further detailed in this manuscript, and some useful recommendations are provided in order to facilitate the decision-making process during the current clinical practice.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Tamoxifeno/uso terapéutico , Antineoplásicos Hormonales/efectos adversos , Inhibidores de la Aromatasa/efectos adversos , Quimioterapia Adyuvante , Ensayos Clínicos como Asunto , Femenino , Humanos , Posmenopausia/fisiología , Receptores de Estrógenos/metabolismo , Tamoxifeno/efectos adversos
16.
Biochemistry ; 47(36): 9688-96, 2008 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-18702522

RESUMEN

Modification of actin at Cys (374) with tetramethylrhodamine maleimide (TMR-actin) has been used for visualization of actin filaments and to produce high-resolution crystal structures of actin. We show that TMR-actin exhibits a 21% decrease in absorbance at 557 nm upon thermal unfolding, likely due to the movement of TMR to a more hydrophobic environment upon rapid unfolding and protein aggregation. We took advantage of this property to test models of actin protein unfolding. A transition temperature ( T m) of 60.2 +/- 0.2 degrees C for Ca (2+).ATP.TMR-actin was determined using A 557 and agreed with our own determinations employing different techniques and previous work with unlabeled actin. Our data show that the dependence of TMR-actin thermal stability on the bound nucleotide and cations follows a trend of Ca (2+).ATP > Mg (2+).ATP > Ca (2+).ADP > Mg (2+).ADP. The activation energies and frequency factors for the thermal unfolding of TMR-actin determined with two methods were in good agreement with those previously determined for unlabeled actin. We observed a biphasic trend in the T m of TMR-actin with increasing nucleotide concentrations, supporting a two-pathway model for actin protein unfolding where one pathway dominates at different concentrations of nucleotide. Additionally, TMR-actin bound by DNase I or gelsolin segment-1 exhibited elevated transition temperatures.


Asunto(s)
Actinas/química , Modelos Moleculares , Pliegue de Proteína , Adenosina Difosfato/química , Adenosina Trifosfato/química , Animales , Calcio/química , Cationes Bivalentes/química , Pollos , Calor , Magnesio/química , Desnaturalización Proteica , Estructura Terciaria de Proteína , Rodaminas/química
17.
J BUON ; 11(4): 425-32, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17309173

RESUMEN

PURPOSE: To evaluate the patient compliance with adjuvant chemotherapy (CT) following radical surgery for non-small cell lung cancer (NSCLC), and to identify the potential confounding factors affecting this particular aspect. PATIENTS AND METHODS: We retrospectively evaluated a series of 356 consecutively treated NSCLC patients at a single institution during 1994-2003. All patients had macroscopic and microscopic radical resection of the primary tumor, with or without mediastinal node dissection or sampling, had received at least one adjuvant CT cycle, with or without postoperative irradiation (RT). CT was planned to be believed for 6 cycles. The following schedules were used: cisplatin (CDDP) 60 mg/m(2), cyclophosphamide 600 mg/m(2) and epirubicin 60 mg/m(2) on day 1 every 21 days (16%);etoposide 120 mg/m(2) and CDDP 30 mg/m(2), on days 1-3, every 21 days (68%); other platinum-based doublets (16%). A multivariate analysis, for a target of 4 and 6 cycles was performed in order to evaluate the potential impact on the patient compliance of the following categories: age, sex (male vs. female), extent of surgery (pneumectomy vs. lesser resection), stage (I,II vs. III), RT(delivered or not) and patient residence (local vs. remote). RESULTS: One hundred and seventy-nine (50%) patients completed all 6 cycles, while 299 (84%) received at least 4 cycles. The median number of administered cycles was 5. For a target of 4 cycles none of the investigated variables had any significant impact. A significant impact on compliance for 6 cycles was recorded for age (OR 0.97, 95% CI 0.95-0.99, p=0.01) and extent of surgery (OR 0.54, 95% CI 0.33-0.87, p=0.01) CONCLUSION: Using the above mentioned combinations, the patient compliance with adjuvant CT was good, with 84% receiving at least 4 and 50% all 6 cycles. The median number of cycles was 5. For a target of 4 cycles none of the investigated variables had a significant impact. For a longer CT duration, age and extent of surgery were correlated with a lower compliance.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Cooperación del Paciente , Adulto , Anciano , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Quimioterapia Adyuvante , Estudios de Cohortes , Femenino , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
18.
J BUON ; 10(3): 323-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-17357185

RESUMEN

During the last years, a strong trend towards excluding anthracyclines from the first-line chemotherapy (CT) of relapsed breast cancer (RBC) has been noticed. This trend is based on the concept of previous exposure of the tumor on the same drugs in the adjuvant setting. Consequently, some guidelines and experts recommend the avoidance of using these compounds for RBC under those circumstances, while the taxanes became the first treatment option. This article gives detailed references about the lack of correlation between the type of adjuvant chemotherapy (including anthracyclines), and the clinical outcome of patients treated with front-line anthracyclines for RBC. It also addresses the weakness of this rationale based on recent translational research data and comments on the fact that anthracyclines could represent the best treatment option for some subcategories of patients with RBC. Concluding, this new trend seems more empirical than evidence-based, and clarification of this issue is warranted.

19.
J BUON ; 9(2): 167-72, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-17415809

RESUMEN

PURPOSE: Recent results coming from large randomized trials suggest that for locally advanced non-small cell lung cancer (NSCLC), integration of chemotherapy (CT) with irradiation (RT) should be concurrent rather than sequential. This study aimed at evaluating the actually delivered RT and CT dose intensities (DI), along with the toxicity and efficacy of a split course RT program with concurrent CT. PATIENTS AND METHODS: From October 2000 to September 2002, 24 patients with histologically or cytologically documented NSCLC were included. Patients' characteristics were as follows: males/females=22/2, median age=59 years, stage IIIB/IIIA=22/2 patients, ECOG PS 0-1=15 (62%) and PS 2=9 (38%). HISTOLOGY: adenocarcinoma/ squamous cell/large cell/unclassified 10/6/1/7, respectively. Four cycles of vinorelbine (VNB) 25 mg/m(2) and cisplatin (CDDP) 40 mg/m(2) on days 1+8 were administered (days 1,8,22,29,57,64,78,85). Concurrent with the second CT cycle, RT (2 courses of 30 Gy separated by a 2-week break) was delivered, with a plan to achieve a total dose of 60 Gy, with a fractionation schedule of 2 Gy/day/5 days weekly. RESULTS: The intended RT dose was delivered to 21 (88%) patients with a relative DI of 0.93. Nineteen (79%) patients received more than 3 CT cycles. The relative DI for VNB and CDDP were 0.88 and 0.83, respectively. During treatment 3 (13%) patients experienced WHO grade 3-4 hematologic toxicity while ECOG grade 3 esophagitis was recorded also in 3 patients. At the end of treatment 14 (58%) patients achieved an objective response (2 complete - CR and 12 partial response - PR), while 8 (33%) patients had stable disease (SD) and 2 (8%) progressive disease (PD). After a median follow up of 15 months (range 3-26), 15 (62%) patients relapsed. There were 8 (33%) patients with local relapse and 7 (29%) with distant metastases. The median progression free (PFS) and overall survival (OS) were 10 (range 2-24) and 15 (range 5-24) months, respectively, with an estimated 1 and 2-year survival rates of 55% and 10%, respectively. CONCLUSION: Our concurrent schedule allows for good CT and RT DI, with low associated toxicities. The efficacy data are considered promising, taking into account the high proportion of stage IIIB patients evaluated.

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