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1.
Artículo en Inglés | MEDLINE | ID: mdl-38765216

RESUMEN

Introductory overview for Methodist DeBakey Cardiovascular Journal Issue 20.3 on Pulmonary Embolism, written by the issues' guest editors.


Asunto(s)
Embolia Pulmonar , Embolia Pulmonar/terapia , Embolia Pulmonar/diagnóstico , Humanos , Factores de Riesgo , Resultado del Tratamiento
2.
Methodist Debakey Cardiovasc J ; 20(3): 13-18, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38765214

RESUMEN

With a multitude of options for pulmonary embolism management, we review the most common diagnostic tools available for assessing risk as well as how each broad risk category is typically treated. Right heart dysfunction is the cornerstone for triage of these patients and should be the focus for decision-making, especially in challenging patients. We aim to provide a modern, clinical perspective for PE management in light of the multitude of intervention options.


Asunto(s)
Toma de Decisiones Clínicas , Embolia Pulmonar , Embolia Pulmonar/terapia , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/fisiopatología , Embolia Pulmonar/diagnóstico por imagen , Humanos , Factores de Riesgo , Resultado del Tratamiento , Medición de Riesgo , Valor Predictivo de las Pruebas , Terapia Trombolítica/efectos adversos , Embolectomía , Procedimientos Endovasculares/efectos adversos , Anticoagulantes/uso terapéutico , Anticoagulantes/efectos adversos , Selección de Paciente , Trombectomía
3.
Eur Arch Otorhinolaryngol ; 281(5): 2645-2653, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38498191

RESUMEN

PURPOSE: Locally-advanced oropharynx (LA-OPSCC) and hypopharynx/larynx (LA-HPLSCC) cancers may be treated with surgical or non-surgical modalities. While survival outcomes are comparable, patterns of disease recurrence are not well established. METHODS: Retrospective review of 98 consecutive patients with LA-OPSCC or LA-HPLSCC treated by either surgery plus adjuvant therapy (S-POAT, n = 48) or chemoradiation (CRT, n = 50). RESULTS: CRT-treated patients had higher recurrence risk (42% vs 14.6%, p = 0.003). This was significant only among LA-OPSCC (p = 0.002) but not LA-HPLSCC patients (p = 0.159). Median time to recurrence in LA-OPSCC was 16.8 vs 11.6 months, and 16.6 vs 15.1 months in LA-HPLSCC, comparing surgically treated and CRT cohorts. Surgically-treated p16-negative LA-OPSCC experienced improved locoregional control than CRT-treated patients (100% vs 12.5%, p = 0.045) and 3-year RFS (83.0% vs 33.3%, p < 0.001). CONCLUSION: Locoregional control and RFS benefit was observed in surgically treated p16 negative LA-OPSCC patients. Locoregional recurrence is the main reason of treatment failure in LA-HNSCC, occurring commonly within the first 2 years post-treatment, regardless of treatment option.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias Orofaríngeas , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Recurrencia Local de Neoplasia/terapia , Quimioradioterapia , Neoplasias de Cabeza y Cuello/terapia , Estudios Retrospectivos , Neoplasias Orofaríngeas/cirugía
4.
Cancer Cytopathol ; 132(5): 309-319, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38319805

RESUMEN

BACKGROUND: Most thyroid nodules are benign. It is important to determine the likelihood of malignancy in such nodules to avoid unnecessary surgery. The primary objective of this study was to characterize the genetic landscape and the performance of a multigene genomic classifier in fine-needle aspiration (FNA) biopsies of cytologically indeterminate thyroid nodules in a Southeast Asian cohort. The secondary objective was to assess the predictive contribution of clinical characteristics to thyroid malignancy. METHODS: This prospective, multicenter, blinded study included 132 patients with 134 nodules. Molecular testing (MT) with ThyroSeq v3 was performed on clinical or ex-vivo FNA samples. Centralized pathology review also was performed. RESULTS: Of 134 nodules, consisting of 61% Bethesda category III, 20% category IV, and 19% category V cytology, and 56% were histologically malignant. ThyroSeq yielded negative results in 37.3% of all FNA samples and in 42% of Bethesda category III-IV cytology nodules. Most positive samples had RAS-like (41.7%), followed by BRAF-like (22.6%), and high-risk (17.9%) alterations. Compared with North American patients, the authors observed a higher proportion of RAS-like mutations, specifically NRAS, in Bethesda categories III and IV and more BRAF-like mutations in Bethesda category III. The test had sensitivity, specificity, negative predictive value, and positive predictive value of 89.6%, 73.7%, 84.0%, and 82.1%, respectively. The risk of malignancy was predicted by positive MT and high-suspicion ultrasound characteristics according to American Thyroid Association criteria. CONCLUSIONS: Even in the current Southeast Asian cohort with nodules that had a high pretest cancer probability, MT could lead to potential avoidance of diagnostic surgery in 42% of patients with Bethesda category III-IV nodules. MT positivity was a stronger predictor of malignancy than clinical parameters.


Asunto(s)
Nódulo Tiroideo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Asia Sudoriental , Biomarcadores de Tumor/genética , Biopsia con Aguja Fina , Genómica/métodos , Mutación , Pronóstico , Estudios Prospectivos , Pueblos del Sudeste Asiático , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/diagnóstico , Nódulo Tiroideo/genética , Nódulo Tiroideo/patología , Nódulo Tiroideo/diagnóstico
6.
Tex Heart Inst J ; 49(2)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35481863

RESUMEN

After the introduction of the first robotic-assisted surgical procedures, the technology soon reached the world of endovascular specialists, giving rise to several publications about robotic-assisted endovascular therapy. Compared with conventional procedures, robotic-assisted procedures can be more accurate and reduce radiation exposure. The latest commercially available endovascular robotic system is the CorPath GRX, which can be operated remotely. Robotic-assisted approaches have proved applicable in the fields of coronary and peripheral vascular intervention and neurointervention. Remote intervention has already proved feasible in the coronary and peripheral vascular systems and, according to expert opinion, could revolutionize acute stroke management as well. We review current knowledge about robotic-assisted therapies and remote interventions, and the future prospects and pitfalls.


Asunto(s)
Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Procedimientos Quirúrgicos Robotizados , Robótica , Enfermedad de la Arteria Coronaria/cirugía , Humanos , Intervención Coronaria Percutánea/instrumentación , Intervención Coronaria Percutánea/métodos , Procedimientos Quirúrgicos Robotizados/instrumentación , Procedimientos Quirúrgicos Robotizados/métodos , Robótica/métodos , Robótica/normas , Resultado del Tratamiento
7.
Front Genet ; 12: 721832, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34512731

RESUMEN

BACKGROUND: The standard of care for thyroid cancer management is thyroidectomy and adjuvant radioactive iodine (RAI). There is a paucity of clinical tool that quantifies residual thyroid volume reliably for precise adjuvant RAI dosing. Serum thyroglobulin (TG), tumour marker for thyroid cancer, takes 4 weeks for complete clearance due to its long half-life, and might be undetectable in 12% of structural disease patients. It detects recurrence with a sensitivity of 19-40%, mainly attributed to issue of TG antibody interference with TG immunometric assay. We hypothesise that the quantity of thyroid-specific cell-free RNA (cfRNA) is indicative of amount of thyroid tissues, and that during thyroid surgery, cfRNA levels decrease accordingly. METHODS: We identified 11 biologically significant and highly expressed thyroid-specific targets from Human Protein Atlas and literature. To assess for a fall in thyroid-specific cfRNA level, we recruited 16 patients undergoing thyroid surgery or RAI for malignant or benign thyroid disease, and tracked longitudinal trend of cfRNA. To assess the utility of cfRNA in detecting metastatic thyroid cancer, cfRNA of 11 patients at intermediate to high risk of recurrence was measured during surveillance and at time of clinical recurrence. RESULTS: The multiplex assay was capable of amplifying and quantifying multiple thyroid-specific genes in a single reaction. The selected targets were amplified successfully from RNA extracted directly from the thyroid (positive control), indicating that they were highly expressed within thyroid tissue. These cfRNAs were present in plasma, in amounts quantifiable using qRT-PCR. Four cfRNA transcripts (TPO, GFRA2, IVD, TG) fell post-treatment in more than 50% of cohort. The thyroid peroxidase (TPO) cfRNA fell post-therapy in 63% of cohort by 80%, as early as 1 day post-treatment, supporting the potential role as early indicator of remnant thyroid tissue volume. We demonstrated the clinical relevance of circulating TPO cfRNA by tracking temporal changes in setting of peri-treatment, recurrence, and TG Ab positive state. CONCLUSION: Using a multiplex pre-amplification approach, the TPO cfRNA was a potential biomarker that can track residual thyroid mass. It can be further optimised for quantification of thyroid volume to guide RAI doses and for detection of thyroid cancer recurrence.

8.
Int J Med Robot ; 17(3): e2249, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33634563

RESUMEN

BACKGROUND: Robotic-assisted endovascular surgery enables us to perform interventions from long distances. This study evaluates the workflow and telecommunication requirements of telerobotic peripheral vascular interventions. METHODS: Ten superficial femoral artery cases were performed by the operator being 44 miles away from the interventional suite, with an endovascular robotic system, on a high-fidelity endovascular simulator. Procedural success, technical success, fluoroscopy time, residual stenosis, contrast dose and network delay were registered. Communication success was assessed after each procedure on a scale from 1 (unacceptable) to 5 (ideal). RESULTS: Procedural success and technical success were 100% and 80%, respectively. The mean residual stenosis, fluoroscopy time and contrast dose were 1.7 ± 5.25%, 6.5 ± 1.8 min and 58.8 ± 14.8 ml. The mean network latency was 38.9 ± 3.5 ms. Median communication success scores were 4.5 (min: 4, max: 5) reported by both the operator and the bedside technician on a scale of 1 (unacceptable) to 5 (ideal). CONCLUSION: With a stable network connection and good communication protocol, a high success rate was achieved for remote robotic-assisted peripheral vascular intervention in an ex vivo model.


Asunto(s)
Procedimientos Endovasculares , Procedimientos Quirúrgicos Robotizados , Estudios de Factibilidad , Humanos , Stents , Resultado del Tratamiento
9.
Eur Arch Otorhinolaryngol ; 278(7): 2461-2471, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32897441

RESUMEN

PURPOSE: Consistent prognosticators are needed to guide adjuvant treatment in tongue squamous cell carcinoma (SCC). We validate the prognostic significance of histopathologic parameters in surgically treated tongue SCC. METHODS: Archival specimens of 88 consecutive patients who were treated surgically for tongue SCC from 2003 to 2016 were re-analyzed by one pathologist. Patient records were retrospectively reviewed. Prognosticators of recurrence-free survival (RFS), overall survival (OS), and disease-specific survival (DSS) were identified using multivariate analysis. RESULTS: Tumor depth of invasion (DOI) > 6 mm (OR 4.76; 95%CI 1.22-18.5; p = 0.024) and lymphovascular invasion (OR 5.61; 95%CI 1.00-31.5; p = 0.05) were independent predictors of nodal metastases. The overall 5-year RFS, OS and DSS were 70%, 82% and 84% respectively. Positive margins predicted poor RFS (HR 3.91; 95%CI 1.58-9.65; p = 0.003) and local recurrence-free survival (HR 4.96; 95%CI 1.36-18; p = 0.015). Presence of nodal metastases (HR 5.03; 95%CI 1.73-14.6; p = 0.003), tumor DOI > 6 mm (HR 9.91; 95%CI 1.26-78.0; p = 0.029) and positive margins (HR 8.26; 95%CI 2.75-24.8; p < 0.001) were independent predictors of poor OS. Presence of nodal metastases (HR 3.87; 95%CI 1.17-12.8; p = 0.027) and positive margins (HR 12.3; 95%CI 3.54-42.9; p < 0.001) also independently predicted poor DSS. CONCLUSION: Margins' status was the only independent predictor of local recurrence. Tumor DOI, nodal and margin status were key prognosticators of survival and may determine the necessity for adjuvant therapy.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de la Lengua , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Humanos , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Lengua/patología , Neoplasias de la Lengua/patología , Neoplasias de la Lengua/cirugía
10.
Int J Infect Dis ; 103: 389-394, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33212260

RESUMEN

BACKGROUND: Migrant worker dormitories-residential complexes where 10-24 workers share living spaces-account for the majority of cases of SARS-CoV-2 infection in Singapore. To prevent overspill of transmission to the wider population, starting in early April 2020, residents were confined to their dormitories while measures were put in place to arrest the spread of infection. This descriptive study presents epidemiological data for a population of more than 60 000 migrant workers living in two barracks-style and four apartment-style dormitories located in western Singapore from April 3 to June 10, 2020. METHODS: Our report draws from data obtained over the first 50 days of outbreak management in order to describe SARS-CoV-2 transmission in high-density housing environments. Cumulative counts of SARS-CoV-2 cases and numbers of housing units affected were analyzed to report the harmonic means of harmonic means of doubling times and their 95% confidence intervals (CI). RESULTS: Multiple transmission peaks were identified involving at least 5467 cases of SARS-CoV-2 infection across six dormitories. Our geospatial heat maps gave an early indication of outbreak severity in affected buildings. We found that the number of cases of SARS-CoV-2 infection doubled every 1.56 days (95% CI 1.29-1.96) in barracks-style buildings. The corresponding doubling time for apartment-style buildings was 2.65 days (95% CI 2.01-3.87). CONCLUSIONS: Geospatial epidemiology was useful in shaping outbreak management strategies in dormitories. Our results indicate that building design plays an integral role in transmission and should be considered in the prevention of future outbreaks.


Asunto(s)
COVID-19/epidemiología , COVID-19/transmisión , Vivienda , Migrantes , Adulto , COVID-19/prevención & control , Brotes de Enfermedades/prevención & control , Humanos , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Singapur/epidemiología , Análisis Espacio-Temporal , Adulto Joven
11.
Nucleic Acids Res ; 48(22): 12727-12745, 2020 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-33245769

RESUMEN

Bcl-2 phosphorylation at serine-70 (S70pBcl2) confers resistance against drug-induced apoptosis. Nevertheless, its specific mechanism in driving drug-resistance remains unclear. We present evidence that S70pBcl2 promotes cancer cell survival by acting as a redox sensor and modulator to prevent oxidative stress-induced DNA damage and execution. Increased S70pBcl2 levels are inversely correlated with DNA damage in chronic lymphocytic leukemia (CLL) and lymphoma patient-derived primary cells as well as in reactive oxygen species (ROS)- or chemotherapeutic drug-treated cell lines. Bioinformatic analyses suggest that S70pBcl2 is associated with lower median overall survival in lymphoma patients. Empirically, sustained expression of the redox-sensitive S70pBcl2 prevents oxidative stress-induced DNA damage and cell death by suppressing mitochondrial ROS production. Using cell lines and lymphoma primary cells, we further demonstrate that S70pBcl2 reduces the interaction of Bcl-2 with the mitochondrial complex-IV subunit-5A, thereby reducing mitochondrial complex-IV activity, respiration and ROS production. Notably, targeting S70pBcl2 with the phosphatase activator, FTY720, is accompanied by an enhanced drug-induced DNA damage and cell death in CLL primary cells. Collectively, we provide a novel facet of the anti-apoptotic Bcl-2 by demonstrating that its phosphorylation at serine-70 functions as a redox sensor to prevent drug-induced oxidative stress-mediated DNA damage and execution with potential therapeutic implications.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Linfoma/tratamiento farmacológico , Mitocondrias/metabolismo , Estrés Oxidativo/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Apoptosis/genética , Proliferación Celular/genética , Cisplatino/farmacología , Daño del ADN/efectos de los fármacos , Doxorrubicina/farmacología , Resistencia a Antineoplásicos/genética , Etopósido/farmacología , Fluorouracilo/farmacología , Humanos , Células Jurkat , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/patología , Linfoma/genética , Linfoma/patología , Mitocondrias/efectos de los fármacos , Mitocondrias/genética , Oxidación-Reducción/efectos de los fármacos , Fosforilación/efectos de los fármacos , Cultivo Primario de Células , Especies Reactivas de Oxígeno/metabolismo , Serina/genética
12.
Expert Rev Med Devices ; 17(9): 919-927, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32835546

RESUMEN

INTRODUCTION: Endovascular surgery has become the standard of care to treat most vascular diseases using a minimally invasive approach. The CorPath system further enhances the potential and enables surgeons to perform robotic-assisted endovascular procedures in interventional cardiology, peripheral vascular surgery, and neurovascular surgery. With the introduction of this technique, the operator can perform multiple steps of endovascular interventions outside of the radiation field with high precision movements even from long-geographical distances. AREAS COVERED: The first and second-generation CorPath systems are currently the only commercially available robotic devices for endovascular surgery. This review article discusses the clinical experiences and outcomes with the robot, the advanced navigational features, and the results with recent hardware and software modifications, which enables the use of the system for neurovascular interventions, and long-distance interventional procedures. EXPERT OPINION: A high procedural success was achieved with the CorPath robotic systems in coronary and peripheral interventions, and the device seems promising in neurovascular procedures. More experience is needed with robotic neurovascular interventions and with complex peripheral arterial cases. In the future, long-distance endovascular surgery can potentially transform the management and treatment of acute myocardial infarction and stroke, with making endovascular care more accessible for patients in remote areas.


Asunto(s)
Procedimientos Endovasculares , Utilización de Procedimientos y Técnicas , Procedimientos Quirúrgicos Robotizados , Procedimientos Endovasculares/instrumentación , Humanos , Exposición Profesional , Protección Radiológica , Procedimientos Quirúrgicos Robotizados/instrumentación , Resultado del Tratamiento
13.
Head Neck ; 42(5): 945-954, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31909854

RESUMEN

OBJECTIVES: To compare the clinical outcomes of oligometastatic versus widely metastatic NPC patients. MATERIALS AND METHODS: Retrospective review of 157 patients with metastatic NPC at a tertiary hospital was performed. Multivariate analysis was carried out to compare the overall and progression-free survival (OS and PFS) of these two cohorts of NPC patients. The number of organ involvement and discrete metastatic lesions associated with improved OS and PFS were ascertained. RESULTS: Patients with oligometastatic NPC (single organ, less than six discrete metastatic lesions) had a better median OS than patients with widespread metastasis (24.8 versus 12.8 months, P < .001). Similarly, the median PFS of oligometastatic NPC was better than that of polymetastatic NPC (11.7 versus 7.3 months, P < .001). CONCLUSION: Single organ disease with less than six discrete lesions is a good indicator of limited metastatic load in NPC, and is associated with improved survival.


Asunto(s)
Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/terapia , Pronóstico , Supervivencia sin Progresión , Estudios Retrospectivos
14.
Redox Biol ; 30: 101403, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31954371

RESUMEN

The death inhibitory proteins, cFLIP and Bcl-2, canonically act at different steps to regulate receptor-mediated apoptosis in cancer cells. Here we report that pharmacological or genetic means to effect an increase in intracellular superoxide result in cFLIP upregulation. Interestingly, Bcl-2 overexpression is associated with a concomitant increase in cFLIP, and reducing superoxide sensitizes Bcl-2 overexpressing cancer cells to receptor-mediated apoptosis via downregulation of cFLIP. Moreover, inhibiting glycolytic flux overcomes apoptosis resistance by superoxide-dependent downregulation of cFLIP. Superoxide-induced upregulation of cFLIP is a function of enhanced transcription, as evidenced by increases in cFLIP promoter activity and mRNA abundance. The positive effect of superoxide on cFLIP is mediated through its reaction with nitric oxide to generate peroxynitrite. Corroborating these findings in cell lines, subjecting primary cells derived from lymphoma patients to glucose deprivation ex vivo, as a means to decrease superoxide, not only reduced cFLIP expression but also significantly enhanced death receptor sensitivity. Based on this novel mechanistic insight into the redox regulation of cancer cell fate, modulation of intracellular superoxide could have potential therapeutic implications in cancers in which these two death inhibitory proteins present a therapeutic challenge.


Asunto(s)
Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/genética , Linfoma/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Superóxidos/metabolismo , Regulación hacia Arriba , Línea Celular Tumoral , Supervivencia Celular , Regulación Neoplásica de la Expresión Génica , Glucólisis , Humanos , Linfoma/genética , Óxido Nítrico/metabolismo , Regiones Promotoras Genéticas , Transducción de Señal
15.
Head Neck Pathol ; 14(2): 542-549, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31273600

RESUMEN

We present a 72 years old male with a left nasal cavity (mammary analogue) secretory carcinoma (SC) which exhibited classical morphological features on light microscopical examination, diffuse strong S100 and mammoglobin positivity on immunohistochemistry, and ETV6-NTRK3 gene fusion on next generation sequencing (NGS) analysis. Unusual features of this tumor are expression of p63 and DOG1 on immunohistochemistry and the atypical junction between Exon 4 of the ETV6 gene and Exon 14 of the NTRK3 gene.


Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma Secretor Análogo al Mamario/genética , Cavidad Nasal/patología , Neoplasias Nasales/genética , Proteínas de Fusión Oncogénica/genética , Anciano , Anoctamina-1/biosíntesis , Exones/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Carcinoma Secretor Análogo al Mamario/patología , Proteínas de la Membrana/biosíntesis , Proteínas de Neoplasias/biosíntesis , Neoplasias Nasales/patología , Análisis de Secuencia de ADN
16.
Cancer Lett ; 457: 151-167, 2019 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-31103719

RESUMEN

Active GTPase-Rac1 is associated with cellular processes involved in carcinogenesis and expression of Bcl-2 endows cells with the ability to evade apoptosis. Here we provide evidence that active Rac1 and Bcl-2 work in a positive feedforward loop to promote sustained phosphorylation of Bcl-2 at serine-70 (S70pBcl-2), which stabilizes its anti-apoptotic activity. Pharmacological and genetic inactivation of Rac1 prevent interaction with Bcl-2 and reduce S70pBcl-2. Similarly, BH3-mimetic inhibitors of Bcl-2 could disrupt Rac1-Bcl-2 interaction and reduce S70pBcl-2. This effect of active Rac1 could also be rescued by scavengers of intracellular superoxide (O2.-), thus implicating NOX-activating activity of Rac1 in promoting S70pBcl-2. Moreover, active Rac1-mediated redox-dependent S70pBcl-2 involves the inhibition of phosphatase PP2A holoenzyme assembly. Sustained S70pBcl-2 in turn secures Rac1/Bcl-2 interaction. Importantly, inhibiting Rac1 activity, scavenging O2.- or employing BH3-mimetic inhibitor significantly reduced S70pBcl-2-mediated survival in cancer cells. Notably, Rac1 expression, and its interaction with Bcl-2, positively correlate with S70pBcl-2 levels in patient-derived lymphoma tissues and with advanced stage lymphoma and melanoma. Together, we provide evidence of a positive feedforward loop involving active Rac1, S70pBcl-2 and PP2A, which could have potential diagnostic, prognostic and therapeutic implications.


Asunto(s)
Linfoma/enzimología , Melanoma/enzimología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Neoplasias Cutáneas/enzimología , Proteína de Unión al GTP rac1/metabolismo , Apoptosis , Progresión de la Enfermedad , Resistencia a Antineoplásicos , Retroalimentación Fisiológica , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Células Jurkat , Linfoma/tratamiento farmacológico , Linfoma/genética , Linfoma/patología , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/patología , Mutación , NADPH Oxidasas/metabolismo , Fosforilación , Unión Proteica , Proteína Fosfatasa 2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Transducción de Señal , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Esferoides Celulares , Superóxidos/metabolismo , Proteína de Unión al GTP rac1/genética
17.
J Vasc Surg Venous Lymphat Disord ; 7(3): 420-427, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30792152

RESUMEN

OBJECTIVE: Outflow tract stenosis is the leading cause of hemodialysis access loss. Many lesions are highly resistant to endovascular treatment, necessitating open surgical intervention. We present our experience using medial claviculectomy for treatment of recalcitrant lesions at the thoracic outlet. METHODS: We retrospectively reviewed patients who underwent medial claviculectomy for dialysis-associated venous thoracic outlet syndrome at our institution between February 2013 and February 2018. Data collection included demographics, past medical history, access history, subsequent procedures, preoperative and postoperative brachial volume flows, and access use. RESULTS: We performed 25 medial claviculectomies in 25 patients with central venous stenosis. Four patients underwent concomitant central venous bypass and were excluded from this study. Twelve accesses were created at our institution; of these, the average access age was 41.6 months (±26.7 months). All patients previously underwent multiple angioplasty attempts to treat outflow stenosis and continued to have residual symptoms and poor fistula function. Medial claviculectomy with venolysis and angioplasty were performed to treat residual outflow stenosis at the level of the subclavian vein. Twenty-one patients had residual stenosis requiring angioplasty. Six patients had subclavian rupture requiring stent graft placement. All patients reported symptom improvement and immediate use of the fistula after medial claviculectomy. Nineteen (76%) patients reported complete resolution of symptoms after the procedure. Ultimately, eight (32%) ipsilateral arteriovenous accesses were lost, and six (24%) patients died in follow-up with patent, functional fistulas. Median length of follow-up was 17 months (interquartile range, 5-28 months). The 18-month primary patency and secondary patency with regard to subclavian vein interventions were 28% (95% confidence interval, 13.8%-56.1%) and 84% (95% confidence interval, 69.7%-100%), respectively. One patient required ligation for high-output cardiac failure. One patient had contralateral brachiocephalic jailing, which was corrected with kissing brachiocephalic stents. CONCLUSIONS: Medial claviculectomy is an effective treatment of recalcitrant central venous stenosis of the thoracic outlet. Balloon angioplasty or stent or stent graft placement is often necessary after extrinsic compression is alleviated and demonstrates acceptable secondary patency rates.


Asunto(s)
Derivación Arteriovenosa Quirúrgica/efectos adversos , Clavícula/cirugía , Descompresión Quirúrgica/métodos , Osteotomía , Diálisis Renal , Vena Subclavia/cirugía , Síndrome del Desfiladero Torácico/cirugía , Enfermedades Vasculares/cirugía , Adulto , Anciano , Angioplastia de Balón/instrumentación , Prótesis Vascular , Implantación de Prótesis Vascular/instrumentación , Clavícula/diagnóstico por imagen , Descompresión Quirúrgica/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteotomía/efectos adversos , Estudios Retrospectivos , Factores de Riesgo , Stents , Vena Subclavia/diagnóstico por imagen , Vena Subclavia/fisiopatología , Síndrome del Desfiladero Torácico/diagnóstico por imagen , Síndrome del Desfiladero Torácico/etiología , Síndrome del Desfiladero Torácico/fisiopatología , Factores de Tiempo , Resultado del Tratamiento , Enfermedades Vasculares/diagnóstico por imagen , Enfermedades Vasculares/etiología , Enfermedades Vasculares/fisiopatología , Grado de Desobstrucción Vascular
18.
Clin Otolaryngol ; 44(2): 114-123, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30294871

RESUMEN

OBJECTIVE: BRAF mutation is the commonest mutation seen in papillary thyroid cancer (PTC), but its prevalence and clinical significance vary across countries. We aim to evaluate the prevalence and clinico-pathological correlation of BRAF mutation in PTC patients at our centre. STUDY DESIGN: Retrospective cohort study of 75 consecutive archival thyroid specimens, whereby BRAF mutation was detected using a polymerase chain reaction (PCR) technique and correlated with clinical and pathological features and outcomes. SETTING: Tertiary university hospital in Singapore. PARTICIPANTS: A total of 75 consecutive histologically proven archival thyroid specimens from patients who underwent thyroidectomy for PTC were accrued for this study. MAIN OUTCOME MEASURES: Main outcome is to determine the prevalence of the BRAF mutation in our South-East Asian population. Secondary aim is to correlate the mutational status with adverse pathological features like histological variants, multi-focality, lymphovascular invasion and extra-thyroidal extension, clinical features like demographics, TNM stage, recurrence and survival, as well as treatment details like type of surgery performed and radioiodine doses. RESULTS: BRAF mutation was detected in 56% (42/75) of PTC. All but one BRAF-mutated PTC had the BRAFV600E mutation. BRAF-mutated tumours were associated with an advanced T-stage (P = 0.049) and were more likely to have a central neck dissection (P = 0.036). There was no significant correlation between BRAF mutation status and clinical outcomes. CONCLUSION: The prevalence of BRAF mutation is 56%. BRAF mutation-positive tumours were associated with locally advanced disease, but not poorer survival.


Asunto(s)
Pueblo Asiatico/genética , Mutación/genética , Recurrencia Local de Neoplasia/epidemiología , Proteínas Proto-Oncogénicas B-raf/genética , Cáncer Papilar Tiroideo/genética , Neoplasias de la Tiroides/genética , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Singapur , Tasa de Supervivencia , Cáncer Papilar Tiroideo/mortalidad , Cáncer Papilar Tiroideo/terapia , Neoplasias de la Tiroides/mortalidad , Neoplasias de la Tiroides/terapia , Tiroidectomía , Adulto Joven
19.
Artículo en Inglés | MEDLINE | ID: mdl-29666673

RESUMEN

In addition to their canonical roles in regulating cell cycle transition and transcription, cyclin-dependent kinases (CDKs) have been shown to coordinate DNA damage response pathways, suggesting a rational pairing of CDK inhibitors with genotoxic chemotherapeutic agents in the treatment of human malignancies. Here, we report that roniciclib (BAY1000394), a potent pan-CDK inhibitor, displays promising anti-neoplastic activity as a single agent and potentiates cisplatin lethality in preclinical nasopharyngeal carcinoma (NPC) models. Proliferation of the NPC cell lines HONE-1, CNE-2, C666-1, and HK-1 was effectively curbed by roniciclib treatment, with IC50 values between 11 and 38 nmol/L. These anticancer effects were mediated by pleiotropic mechanisms consistent with successful blockade of cell cycle CDKs 1, 2, 3, and 4 and transcriptional CDKs 7 and 9, ultimately resulting in arrest at G1/S and G2/M, downregulation of the transcriptional apparatus, and repression of anti-apoptotic proteins. Considerably enhanced tumor cell apoptosis was achieved following combined treatment with 10 nmol/L roniciclib and 2.0 µmol/L cisplatin; this combination therapy achieved a response over 250% greater than either drug alone. Although roniciclib chemosensitized NPC cells to cisplatin, it did not sensitize untransformed (NP69) cells. The administration of 0.5 mg/kg roniciclib to BALB/c xenograft mice was well tolerated and effectively restrained tumor growth comparable to treatment with 6 mg/kg cisplatin, whereas combining these two agents produced far greater tumor suppression than either of the monotherapies. In summary, these data demonstrate that roniciclib has strong anti-NPC activity and synergizes with cisplatin chemotherapy at clinically relevant doses, thus justifying further evaluation of this combinatorial approach in clinical settings.

20.
Cancer Res ; 77(23): 6614-6626, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-28951465

RESUMEN

Nasopharyngeal carcinoma (NPC) is an invasive cancer with particularly high incidence in Southeast Asia and Southern China. The pathogenic mechanisms of NPC, particularly those involving epigenetic dysregulation, remain largely elusive, hampering clinical management of this malignancy. To identify novel druggable targets, we carried out an unbiased high-throughput chemical screening and observed that NPC cells were highly sensitive to inhibitors of cyclin-dependent kinases (CDK), especially THZ1, a covalent inhibitor of CDK7. THZ1 demonstrated pronounced antineoplastic activities both in vitro and in vivo An integrative analysis using both whole-transcriptome sequencing and chromatin immunoprecipitation sequencing pinpointed oncogenic transcriptional amplification mediated by super-enhancers (SE) as a key mechanism underlying the vulnerability of NPC cells to THZ1 treatment. Further characterization of SE-mediated networks identified many novel SE-associated oncogenic transcripts, such as BCAR1, F3, LDLR, TBC1D2, and the long noncoding RNA TP53TG1. These transcripts were highly and specifically expressed in NPC and functionally promoted NPC malignant phenotypes. Moreover, DNA-binding motif analysis within the SE segments suggest that several transcription factors (including ETS2, MAFK, and TEAD1) may help establish and maintain SE activity across the genome. Taken together, our data establish the landscape of SE-associated oncogenic transcriptional network in NPC, which can be exploited for the development of more effective therapeutic regimens for this disease. Cancer Res; 77(23); 6614-26. ©2017 AACR.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma/genética , Carcinoma/patología , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Fenilendiaminas/farmacología , Pirimidinas/farmacología , Animales , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Carcinoma Nasofaríngeo , Proteína Proto-Oncogénica c-ets-2/genética , ARN Largo no Codificante/genética , Transcripción Genética/efectos de los fármacos , Transcripción Genética/genética , Ensayos Antitumor por Modelo de Xenoinjerto , Quinasa Activadora de Quinasas Ciclina-Dependientes
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