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1.
Nature ; 539(7627): 112-117, 2016 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-27595394

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is characterized by inactivation of the von Hippel-Lindau tumour suppressor gene (VHL). Because no other gene is mutated as frequently in ccRCC and VHL mutations are truncal, VHL inactivation is regarded as the governing event. VHL loss activates the HIF-2 transcription factor, and constitutive HIF-2 activity restores tumorigenesis in VHL-reconstituted ccRCC cells. HIF-2 has been implicated in angiogenesis and multiple other processes, but angiogenesis is the main target of drugs such as the tyrosine kinase inhibitor sunitinib. HIF-2 has been regarded as undruggable. Here we use a tumourgraft/patient-derived xenograft platform to evaluate PT2399, a selective HIF-2 antagonist that was identified using a structure-based design approach. PT2399 dissociated HIF-2 (an obligatory heterodimer of HIF-2α-HIF-1ß) in human ccRCC cells and suppressed tumorigenesis in 56% (10 out of 18) of such lines. PT2399 had greater activity than sunitinib, was active in sunitinib-progressing tumours, and was better tolerated. Unexpectedly, some VHL-mutant ccRCCs were resistant to PT2399. Resistance occurred despite HIF-2 dissociation in tumours and evidence of Hif-2 inhibition in the mouse, as determined by suppression of circulating erythropoietin, a HIF-2 target and possible pharmacodynamic marker. We identified a HIF-2-dependent gene signature in sensitive tumours. Gene expression was largely unaffected by PT2399 in resistant tumours, illustrating the specificity of the drug. Sensitive tumours exhibited a distinguishing gene expression signature and generally higher levels of HIF-2α. Prolonged PT2399 treatment led to resistance. We identified binding site and second site suppressor mutations in HIF-2α and HIF-1ß, respectively. Both mutations preserved HIF-2 dimers despite treatment with PT2399. Finally, an extensively pretreated patient whose tumour had given rise to a sensitive tumourgraft showed disease control for more than 11 months when treated with a close analogue of PT2399, PT2385. We validate HIF-2 as a target in ccRCC, show that some ccRCCs are HIF-2 independent, and set the stage for biomarker-driven clinical trials.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/antagonistas & inhibidores , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/metabolismo , Indanos/farmacología , Indanos/uso terapéutico , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/metabolismo , Sulfonas/farmacología , Sulfonas/uso terapéutico , Animales , Translocador Nuclear del Receptor de Aril Hidrocarburo/genética , Translocador Nuclear del Receptor de Aril Hidrocarburo/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Sitios de Unión , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Línea Celular Tumoral , Transformación Celular Neoplásica , Resistencia a Antineoplásicos/efectos de los fármacos , Eritropoyetina/antagonistas & inhibidores , Eritropoyetina/sangre , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Indanos/administración & dosificación , Indoles/farmacología , Indoles/uso terapéutico , Neoplasias Renales/genética , Neoplasias Renales/patología , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Terapia Molecular Dirigida , Mutación , Pirroles/farmacología , Pirroles/uso terapéutico , Reproducibilidad de los Resultados , Sulfonas/administración & dosificación , Sunitinib , Ensayos Antitumor por Modelo de Xenoinjerto
2.
Oncologist ; 22(4): 369-374, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28314841

RESUMEN

Multiple factors critical to the effectiveness of academic phase I cancer programs were assessed among 16 academic centers in the U.S. Successful cancer centers were defined as having broad phase I and I/II clinical trial portfolios, multiple investigator-initiated studies, and correlative science. The most significant elements were institutional philanthropic support, experienced clinical research managers, robust institutional basic research, institutional administrative efforts to reduce bureaucratic regulatory delays, phase I navigators to inform patients and physicians of new studies, and a large cancer center patient base. New programs may benefit from a separate stand-alone operation, but mature phase I programs work well when many of the activities are transferred to disease-oriented teams. The metrics may be useful as a rubric for new and established academic phase I programs. The Oncologist 2017;22:369-374.


Asunto(s)
Centros Médicos Académicos , Neoplasias/epidemiología , Ensayos Clínicos como Asunto , Humanos , Neoplasias/genética , Desarrollo de Programa , Estados Unidos
3.
Transfus Apher Sci ; 56(3): 431-433, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28512017

RESUMEN

Von Willebrand disease (VWD) is the most common congenital bleeding disorder and is due to quantitative or qualitative defects of von Willebrand factor (VWF). Acquired defects of VWF, termed acquired von Willebrand syndrome (AVWS), are due to a host of different mechanisms. Autoantibody-mediated AVWS may be associated with lymphoproliferative or immunological disorders, such as systemic lupus erythematosus (SLE). A large majority of AVWS cases are type 1 or type 2A-like and patients tend to have a mild to moderate bleeding tendency. We report a case of severe autoimmune AVWS in a woman with SLE who presented with clinical and laboratory features of type 3 VWD (undetectable VWF antigen, ristocetin cofactor activity, and VWF multimers). A mixing study demonstrated an inhibitor to VWF (6BU/mL). Her bleeds were managed with antifibrinolytics, recombinant activated factor VII, and activated prothrombin complex concentrate. She was initially treated with steroids and intravenous immunoglobulin therapy. However, her bleeding symptoms continued until she was treated with rituximab, and her VWF parameters normalized. She relapsed two years later due to non-compliance with her immunosuppressive medications and expired another two years later secondary to complications of sepsis and uremic pericarditis. This case emphasizes the importance of aggressive initial therapy of SLE to reduce secondary complications, frequent patient monitoring, and continued treatment of the underlying autoimmune disorder in patients with AVWS.


Asunto(s)
Enfermedades Autoinmunes/diagnóstico , Enfermedades de von Willebrand/diagnóstico , Adulto , Enfermedades Autoinmunes/mortalidad , Enfermedades Autoinmunes/patología , Femenino , Humanos , Análisis de Supervivencia , Adulto Joven , Enfermedades de von Willebrand/mortalidad , Enfermedades de von Willebrand/patología
4.
J Urol ; 195(1): 180-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26300218

RESUMEN

PURPOSE: In clear cell renal cell carcinoma BAP1 and PBRM1 are 2 of the most commonly mutated genes (10% to 15% and 40% to 50%, respectively). We sought to determine the prognostic significance of PBRM1 and BAP1 expression in clear cell renal cell carcinoma. MATERIALS AND METHODS: We used immunohistochemistry to assess PBRM1 protein expression in 1,479 primary clear cell renal cell carcinoma tumors that were previously stained for BAP1. A centralized pathologist reviewed all cases and categorized tumors as positive or deficient for PBRM1 and BAP1. Kaplan-Meier and Cox regression models were used to evaluate association of PBRM1 and BAP1 expression with the risk of death from renal cell carcinoma and the risk of metastasis after adjustment for age and the Mayo Clinic SSIGN (stage, size, grade and necrosis) score. RESULTS: PBRM1 and BAP1 expression was PBRM1+ BAP1+ in 40.1% of tumors, PBRM1- BAP1+ in 48.6%, PBRM1+ BAP1- in 8.7% and PBRM1- BAP1- in 1.8%. The incidence of PBRM1 and BAP1 loss in the same tumor was significantly lower than expected (actual 1.8% vs expected 5.3%, p <0.0001). Compared to patients with PBRM1+ BAP1+ tumors those with PBRM1- BAP1+ lesions were more likely to die of renal cell carcinoma (HR 1.39, p = 0.035), followed by those with PBRM1+ BAP1- and PBRM1- BAP1- tumors (HR 3.25 and 5.2, respectively, each p <0.001). PBRM1 and BAP1 expression did not add independent prognostic information to the SSIGN score. CONCLUSIONS: PBRM1 and BAP1 expression identified 4 clinical subgroups of patients with clear cell renal cell carcinoma who had divergent clinical outcomes. The clinical value of these biomarkers will be fully realized when therapies targeting pathways downstream of PBRM1 and BAP1 are developed.


Asunto(s)
Carcinoma de Células Renales/clasificación , Carcinoma de Células Renales/genética , Neoplasias Renales/clasificación , Neoplasias Renales/genética , Proteínas Nucleares/genética , Factores de Transcripción/genética , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética , Adulto , Anciano , Anciano de 80 o más Años , Proteínas de Unión al ADN , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Células Tumorales Cultivadas , Adulto Joven
5.
Blood ; 121(14): 2669-77, 2013 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-23365458

RESUMEN

Mutations in the transcription factor GATA2 underlie the syndrome of monocytopenia and B- and natural killer (NK)-cell lymphopenia associated with opportunistic infections and cancers. In addition, patients have recurrent and severe viral infections. NK cells play a critical role in mediating antiviral immunity. Human NK cells are thought to mature in a linear fashion, with the CD56(bright) stage preceding terminal maturation to the CD56(dim) stage, considered the most enabled for cytotoxicity. Here we report an NK cell functional defect in GATA2-deficient patients and extend this genetic lesion to what is considered to be the original NK cell-deficient patient. In most cases, GATA2 deficiency is accompanied by a severe reduction in peripheral blood NK cells and marked functional impairment. The NK cells detected in peripheral blood of some GATA2-deficient patients are exclusively of the CD56(dim) subset, which is recapitulated on in vitro NK cell differentiation. In vivo, interferon α treatment increased NK cell number and partially restored function but did not correct the paucity of CD56(bright) cells. Thus, GATA2 is required for the maturation of human NK cells and the maintenance of the CD56(bright) pool in the periphery. Defects in GATA2 are a novel cause of profound NK cell dysfunction.


Asunto(s)
Antígeno CD56/inmunología , Diferenciación Celular/inmunología , Factor de Transcripción GATA2/genética , Células Asesinas Naturales/inmunología , Linfopenia/genética , Antígenos CD34/metabolismo , Antígeno CD56/metabolismo , Citotoxicidad Inmunológica/inmunología , Factor de Transcripción GATA2/inmunología , Factor de Transcripción GATA2/metabolismo , Humanos , Inmunofenotipificación , Células K562 , Células Asesinas Naturales/citología , Células Asesinas Naturales/metabolismo , Activación de Linfocitos/inmunología , Recuento de Linfocitos , Linfopenia/inmunología , Linfopenia/metabolismo , Células del Estroma/citología , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo
6.
Cancer Sci ; 105(8): 1040-8, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24837299

RESUMEN

Epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) are validated molecular targets in cancer therapy. Dual blockade has been explored and one such agent, lapatinib, is in clinical practice but with modest activity. Through chemical screening, we discovered a novel EGFR and HER2 inhibitor, S-222611, that selectively inhibited both kinases with IC50 s below 10 nmol/L. S-222611 also inhibited intracellular kinase activity and the growth of EGFR-expressing and HER2-expressing cancer cells. In addition, S-222611 showed potent antitumor activity over lapatinib in a variety of xenograft models. In evaluations with two patient-oriented models, the intrafemoral implantation model and the intracranial implantation model, S-222611 exhibited excellent activity and could be effective against bone and brain metastasis. Compared to neratinib and afatinib, irreversible EGFR/HER2 inhibitors, S-222611 showed equivalent or slightly weaker antitumor activity but a safer profile. These results indicated that S-222611 is a potent EGFR and HER2 inhibitor with substantially better antitumor activity than lapatinib at clinically relevant doses. Considering the safer profile than for irreversible inhibitors, S-222611 could be an important option in future cancer therapy.


Asunto(s)
Antineoplásicos/farmacología , Receptores ErbB/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/farmacología , Receptor ErbB-2/antagonistas & inhibidores , Animales , Línea Celular Tumoral , Modelos Animales de Enfermedad , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ratones , Ratones Desnudos , Ratones SCID , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Cancer ; 120(7): 1059-67, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24382589

RESUMEN

BACKGROUND: The majority of patients diagnosed with clear cell renal cell carcinoma (ccRCC) have low-risk disease with a < 10% chance of ccRCC-specific death. DNA sequencing revealed that mutations in BAP1 (BRCA1 associated protein-1) occur in 5% to 15% of ccRCC cases and are associated with poor outcomes. The vast majority of BAP1 mutations abolish protein expression. In this study, we used a highly sensitive and specific immunohistochemistry (IHC) assay to test whether BAP1 expression is an independent marker of ccRCC-specific survival, particularly in patients with low-risk disease. METHODS: BAP1 expression was assessed, using IHC, in 1479 patients who underwent nephrectomy to treat clinically localized ccRCC. A centralized pathologist dichotomized patients as either BAP1-positive or BAP1-negative. The authors employed Kaplan-Meier and Cox regression models to associate BAP1 expression with cancer-specific survival. RESULTS: A total of 10.5% of tumors were BAP1-negative, 84.8% of tumors were BAP1-positive, and 4.6% of tumors had ambiguous staining for BAP1. Patients with BAP1-negative tumors have an increased risk of ccRCC-related death (hazard ratio [HR] = 3.06; 95% confidence interval [CI] = 2.28-4.10; P = 6.77 × 10(-14) ). BAP1 expression remained an independent marker of prognosis after adjusting for the UCLA integrated staging system (UISS) (HR = 1.67; 95% CI = 1.24-2.25; P < .001). Finally, BAP1 was an independent prognostic marker in low-risk patients with a Mayo Clinic stage, size, grade, and necrosis (SSIGN) score of ≤ 3 (HR = 3.24; 95% CI = 1.26-8.33; P = .015). CONCLUSIONS: This study used a large patient cohort to demonstrate that BAP1 expression is an independent marker of prognosis in patients with low-risk (SSIGN≤ 3) ccRCC.


Asunto(s)
Carcinoma de Células Renales/metabolismo , Neoplasias Renales/metabolismo , Proteínas Supresoras de Tumor/biosíntesis , Ubiquitina Tiolesterasa/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/biosíntesis , Biomarcadores de Tumor/genética , Carcinoma de Células Renales/genética , Estudios de Cohortes , Femenino , Humanos , Inmunohistoquímica , Neoplasias Renales/genética , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Análisis de Supervivencia , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética
8.
Biomed Microdevices ; 15(4): 673-681, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23109037

RESUMEN

Combining the power of immunomagnetic assay and microfluidic microchip operations, we successfully detected rare CTCs from clinical blood samples. The microfluidic system is operated in a flip-flop mode, where a computer-controlled rotational holder with an array of microfluidic chips inverts the microchannels. We have demonstrated both theoretically and experimentally that the direction of red blood cell (RBC) sedimentation with regards to the magnetic force required for cell separation is important for capture efficiency, throughput, and purity. The flip-flop operation reduces the stagnation of RBCs and non-specific binding on the capture surface by alternating the direction of the magnetic field with respect to gravity. The developed immunomagnetic microchip-based screening system exhibits high capture rates (more than 90%) for SkBr3, PC3, and Colo205 cell lines in spiked screening experiments and successfully isolates CTCs from patient blood samples. The proposed motion controlled microchip-based immunomagnetic system shows great promise as a clinical tool for cancer diagnosis and prognosis.


Asunto(s)
Separación Inmunomagnética/instrumentación , Técnicas Analíticas Microfluídicas/instrumentación , Movimiento (Física) , Nanotecnología/instrumentación , Células Neoplásicas Circulantes/patología , Sedimentación Sanguínea , Línea Celular Tumoral , Eritrocitos/citología , Humanos , Campos Magnéticos , Neoplasias/sangre , Viscosidad
9.
Int J Cancer ; 128(12): 2823-32, 2011 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-20734393

RESUMEN

Conventional chemotherapy is commonly used for advanced stages of bladder cancer with modest success and high morbidity. Identifying markers of resistance will allow clinicians to tailor treatment to a specific patient population. T24-tumorigenic cell line was grown orthotopically in nude mice and monitored using bioluminescence imaging and microcomputed tomography until they developed metastases. Stable sublines were then developed from primary bladder (T24-P), lung (T24-L) and bone (T24-B) tissues. Chromosomal analysis and DNA microarray were used to characterize these sublines. Real-time quantitative polymerase chain reaction and immunohistochemistry were used for validation. Epigenetic modifiers were used to study gene regulation. The cell viability was quantified with MTT assay. Chromosomal analysis revealed multiple alterations in metastatic cell lines compared to T24-P. DNA microarray analysis showed that taxol resistance-associated gene (TRAG) 3 was the most upregulated gene. From real-time quantitative polymerase chain reaction and immunohistochemistry, TRAG3 was significantly higher in T24-L and T24-B than T24-P. TRAG3 gene expression is likely controlled by DNA methylation but not histone acetylation. Interestingly, T24-B and T24-L cells were more resistant than T24-P to treatment with antimicrotubule agents such as docetaxel, paclitaxel and vinblastine. TRAG3 mRNA expression was higher in 20% of patients with ≤ pT2 (n = 10) and 60% of patients with ≥ pT3 (n = 20) compared to normal adjacent tissue (p = 0.05). In addition, the median TRAG3 expression was 6.7-fold higher in ≥ pT3 tumors compared to ≤ pT2 tumors. Knowing the status of TRAG3 expression could help clinicians tailor treatment to a particular patient population that could benefit from treatment, while allocating patients with resistant tumors to new experimental therapies.


Asunto(s)
Carcinoma de Células Transicionales/genética , Proteínas de Neoplasias/genética , Regulación hacia Arriba , Neoplasias de la Vejiga Urinaria/genética , Adulto , Anciano , Anciano de 80 o más Años , Animales , Secuencia de Bases , Carcinoma de Células Transicionales/patología , Cartilla de ADN , Femenino , Humanos , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Metástasis de la Neoplasia , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa , Neoplasias de la Vejiga Urinaria/patología
10.
Platelets ; 21(6): 460-3, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20536288

RESUMEN

Platelet aggregation study is performed to investigate platelet function abnormality. A normal healthy control sample is usually run with the patient sample as a quality control measure. At our institution, we observed variations in platelet aggregation responses in our normal repeat controls. Therefore, we analysed aggregation parameters in these controls. Whole blood aggregation studies were performed with adenosine diphosphate (ADP), arachidonic acid (AA), collagen and ristocetin. Adenosine triphosphate (ATP) secretion was also measured simultaneously by leuciferin-leuciferase reaction. During a 5-year period, a total of 86 studies were performed on seven controls. Aggregations were within the acceptable range in 67% of the time. Collagen was the most affected agonist in our study. On five occasions, four controls had subnormal aggregations with two agonists. All abnormal responses were hypoaggregation except for two who had hyperaggregation with collagen and AA. Only one out of seven controls was always normal. In the presence of a subnormal control result, a new control was run before releasing the patient's platelet aggregation results. These findings suggest that many physiological factors, other than medications, may affect platelet function even in normal individuals. Therefore, a repeat study at a later date to demonstrate a reproducible abnormality would be prudent before labeling a patient's platelets abnormal.


Asunto(s)
Plaquetas/fisiología , Agregación Plaquetaria/fisiología , Adenosina Difosfato/farmacología , Adenosina Trifosfato/sangre , Adenosina Trifosfato/metabolismo , Adulto , Ácido Araquidónico/farmacología , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Colágeno/farmacología , Femenino , Programas Gente Sana , Humanos , Masculino , Persona de Mediana Edad , Agregación Plaquetaria/efectos de los fármacos , Pruebas de Función Plaquetaria/métodos , Control de Calidad , Estudios Retrospectivos , Ristocetina/farmacología
11.
Clin Cancer Res ; 14(4): 1200-7, 2008 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18281555

RESUMEN

PURPOSE: Romidepsin (FK228, depsipeptide, FR901228), a unique cyclic depsipeptide with a histone deacetylase inhibitor (HDACI) activity, is a potential cancer therapeutic agent and currently under clinical trials for several types of cancer. For bladder cancer, romidepsin seems to be a potent antitumor agent from our recent study. In this study, we further delineate a new agent that can enhance both HDACI and antitumor activity of romidepsin. EXPERIMENTAL DESIGN: We screened a chemical library to identify candidate(s) that could enhance romidepsin activity. Chemical synthesis and purification were carried out to produce pure compound to examine its biochemical and antitumor effect on bladder cancer cell lines both in vitro and in vivo. RESULTS: Tranilast, N-(acetoacetyl) anthranilic acid, was first identified as a lead compound from screening, and then, one of the analogues, 2,3-dimethoxycinnamoyl azide (DMCA), seems to be more potent than tranilast. Our data indicate that DMCA can potentiate the HDACI activity of romidepsin and other biological activities, such as cell cycle arrest and apoptosis; these effects were accompanied with the expression of various key cell cycle regulators in different bladder cancer cells. Consistently, DMCA can enhance the in vivo antitumor effect of romidepsin without causing any more weight loss than romidepsin alone. CONCLUSION: DMCA is able to enhance the antitumor effect of romidepsin on bladder cancer from in vitro and in vivo.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Azidas/administración & dosificación , Cinamatos/administración & dosificación , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Ciclo Celular/efectos de los fármacos , Proliferación Celular , Depsipéptidos/administración & dosificación , Inhibidores Enzimáticos/administración & dosificación , Histona Desacetilasas/metabolismo , Humanos , Ratones , Ratones Desnudos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ensayos Antitumor por Modelo de Xenoinjerto , ortoaminobenzoatos/química
12.
Methods Mol Biol ; 1866: 163-171, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30725415

RESUMEN

This chapter reviews how total methionine (MET) restriction (MR) of a human brain tumor xenograft, effected by the combination of recombinant L-methionine-α-deamino-γ-lyase (rMETase) and a MET-free diet, greatly potentiates standard chemotherapy for brain tumors in mouse models. The growth of human brain tumor Daoy, SWB77, and D-54 xenografts in nude mice was arrested after the depletion of mouse plasma methionine (MET) with a combination of an MR diet and rMETase and homocysteine to rescue normal cells and tissues. MET was depleted to below 5 µm by this treatment. MR for 10-12 days inhibited tumor growth, but did not prevent tumor regrowth after treatment cessation. A single dose of N,N'-bis(2-chloroethyl)-N-nitrosourea (BCNU), which was ineffective alone, was administered at the end of the MR regimen, and caused a more than 80-day growth delay for Daoy and D-54 and a 20-day growth delay for SWB77. The total MR treatment regimens also increased the efficacy of temozolomide (TMZ) against the SWB77 xenograft when administered at the end of the MET regimen.


Asunto(s)
Metionina/deficiencia , Neoplasias/dietoterapia , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Colina , Homocisteína/metabolismo , Humanos , Hígado/efectos de los fármacos , Hígado/patología , Metionina/sangre , Ratones Desnudos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Temozolomida/farmacología , Temozolomida/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Cancer Epidemiol Biomarkers Prev ; 17(4): 995-1000, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18398044

RESUMEN

Detection of cancer cells at early stages could potentially increase survival rates in cancer patients. Aberrant promoter hypermethylation is a major mechanism for silencing tumor suppressor genes in many kinds of human cancers. A recent report from our laboratory described the use of quantitative methylation-specific PCR assays for discriminating patients with lung cancer from those without lung cancer using lung biopsies as well as sputum samples. TCF21 is known to be essential for differentiation of epithelial cells adjacent to mesenchyme. Using restriction landmark genomic scanning, a recent study identified TCF21 as candidate tumor suppressor at 6q23-q24 that is epigenetically inactivated in lung and head and neck cancers. Using DNA sequencing technique, we narrowed down a short CpG-rich segment (eight specific CpG sites in the CpG island within exon 1) of the TCF21 gene, which was unmethylated in normal lung epithelial cells but predominantly methylated in lung cancer cell lines. We specifically targeted this short CpG-rich sequence and developed a quantitative methylation-specific PCR assay suitable for high-throughput analysis. We showed the usefulness of this assay in discriminating patients with lung cancer from those without lung cancer using biopsies and sputum samples. We further showed similar applications with multiple other malignancies. Our assay might have important implications in early detection and surveillance of multiple malignancies.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Biomarcadores de Tumor/genética , Metilación de ADN , Exones/genética , Neoplasias/genética , Humanos
14.
Urol Oncol ; 26(1): 57-64, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18190833

RESUMEN

Nanoparticles (size in nanometer range) provide a new mode of cancer drug delivery functioning as a carrier for entry through fenestrations in tumor vasculature allowing direct cell access. These particles allow exquisite modification for binding to cancer cell membranes, the microenvironment, or to cytoplasmic or nuclear receptor sites. This results in delivery of high drug concentrations to the targeted cancer cell, with reduced toxicity of normal tissue. Several such engineered drugs are in clinical practice, including liposomal doxorubicin and albumin conjugate paclitaxel. The carrier mediated paclitaxel has already shown significant efficacy in taxane resistant cancers, an approach highly relevant in prostate cancer, where taxanes are the treatment of choice. Other modifications including transferrin receptor and folate receptor targeted drug delivery molecules are in study. This new technology provides many exciting therapeutic approaches for targeted high concentration drug delivery to cancer cells with reduced injury of normal cells.


Asunto(s)
Antineoplásicos/uso terapéutico , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas , Neoplasias/tratamiento farmacológico , Antineoplásicos/administración & dosificación , Diseño de Fármacos , Resistencia a Múltiples Medicamentos/fisiología , Humanos , Liposomas , Nanocápsulas
15.
Hematol Oncol Clin North Am ; 21(4): 647-61, vi, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17666283

RESUMEN

Acquired platelet dysfunction is encountered frequently in clinical practice. The usual clinical presentation is that of mucosal bleeding, epistaxis, or superficial epidermal bleeds. Often, the dysfunctional platelets are related to a medication or a systemic disorder. Normally, when platelets are exposed to damaged endothelium, they adhere to the exposed basement membrane collagen and change their shape from smooth disks to spheres with pseudopodia. Then, they secrete the contents of their granules, a process referred to as the release reaction. Additional platelets form aggregates on those platelets that have adhered to the vessel wall. As a result, the primary hemostatic plug is formed, and bleeding is arrested. This article reviews the various forms of acquired platelet dysfunction that result in decreased platelet aggregation, adhesion, or secretion.


Asunto(s)
Trastornos de las Plaquetas Sanguíneas/etiología , Puente Cardiopulmonar/efectos adversos , Enfermedad , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos
16.
Neoplasia ; 19(10): 848-855, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28923537

RESUMEN

This is the first prospective study of the effects of human gut microbiota and metabolites on immune checkpoint inhibitor (ICT) response in metastatic melanoma patients. Whereas many melanoma patients exhibit profound response to ICT, there are fewer options for patients failing ICT-particularly with BRAF-wild-type disease. In preclinical studies, specific gut microbiota promotes regression of melanoma in mice. We therefore conducted a study of the effects of pretreatment gut microbiota and metabolites on ICT Response Evaluation Criteria in Solid Tumors response in 39 metastatic melanoma patients treated with ipilimumab, nivolumab, ipilimumab plus nivolumab (IN), or pembrolizumab (P). IN yielded 67% responses and 8% stable disease; P achieved 23% responses and 23% stable disease. ICT responders for all types of therapies were enriched for Bacteroides caccae. Among IN responders, the gut microbiome was enriched for Faecalibacterium prausnitzii, Bacteroides thetaiotamicron, and Holdemania filiformis. Among P responders, the microbiome was enriched for Dorea formicogenerans. Unbiased shotgun metabolomics revealed high levels of anacardic acid in ICT responders. Based on these pilot studies, both additional confirmatory clinical studies and preclinical testing of these bacterial species and metabolites are warranted to confirm their ICT enhancing activity.


Asunto(s)
Microbioma Gastrointestinal , Melanoma/etiología , Melanoma/metabolismo , Metabolómica , Metagenoma , Metagenómica , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Inmunológicos/farmacología , Antineoplásicos Inmunológicos/uso terapéutico , Biomarcadores de Tumor , Cromatografía Líquida de Alta Presión , Análisis por Conglomerados , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Melanoma/tratamiento farmacológico , Melanoma/patología , Metabolómica/métodos , Metagenómica/métodos , Persona de Mediana Edad , Terapia Molecular Dirigida , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Espectrometría de Masas en Tándem , Resultado del Tratamiento
17.
Cancer Lett ; 242(2): 222-30, 2006 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-16458425

RESUMEN

We investigated aberrant methylation in 101 prostate cancers(PCa) and 32 histologically normal prostate tissues. We focused on genes largely in the apoptotic pathway. Methylation frequencies of the genes were Reprimo, 54%; TMS1, 47%; DcR1, 45%; RRAD, 37%; DcR2, 37%; CRBP1, 34%; HPP1, 32%; RIZ1, 31%; DRM/Gremlin, 21%; SOCS1, 20%; DR4, 5%; DR5, 1%. Methylation of Reprimo and TMS1 correlate with preoperative serum prostate-specific antigen. Methylation of TMS1, DcR1, DcR2, and CRBP1 correlate with Gleason score. Methylation of TMS1 and unmethylation of both DcR1 and DcR2 correlate with poorer disease free survival by univariate and multivariate analyses. Our data suggest that methylation of multiple genes may be involved in pathogenesis and correlate with prognosis of PCa.


Asunto(s)
Apoptosis , Metilación de ADN , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , ADN/química , ADN/metabolismo , Cartilla de ADN/química , Supervivencia sin Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Neoplasias de la Próstata/diagnóstico
18.
Urol Oncol ; 24(2): 152-60, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16520279

RESUMEN

Prostate cancer and transitional cell carcinoma (TCC) of bladder are the 2 most common malignancies in the male adult urogenital system. Epigenetic gene silencing, particularly tumor suppressor genes, has become a new area of cancer research. Agents such as deoxyribonucleic acid methyltransferase inhibitors or histone deacetylase inhibitors are epigenetic modifiers that can restore gene expression and alter the malignant phenotype of cancer. They provide a new therapeutic avenue for prostate cancer and TCC. It is also likely that combination regimens using epigenetic modifiers with other classes of agents may have higher therapeutic efficacy for prostate cancer and TCC, especially metastatic and/or refractory cases. We review current knowledge of epigenetic event in prostate cancer and TCC, and discuss the possible clinical implications for these 2 diseases.


Asunto(s)
Carcinoma de Células Transicionales/terapia , Terapia Genética , Inhibidores de Histona Desacetilasas , Neoplasias de la Próstata/terapia , Neoplasias de la Vejiga Urinaria/terapia , Carcinoma de Células Transicionales/genética , Epigénesis Genética , Humanos , Masculino , Neoplasias de la Próstata/genética , Neoplasias de la Vejiga Urinaria/genética
19.
Cancer Res ; 63(24): 8680-6, 2003 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-14695181

RESUMEN

Coxsackie and adenovirus receptor (CAR) is not only a high-affinity receptor for adenovirus, but also a tumor inhibitor in both prostate and bladder cancer lines. Decreased CAR gene expression is often detected in cancer specimens; however, the mechanism(s) is still unknown. In this study, we cloned the entire CAR gene and characterized the core promoter sequence of the CAR gene. The CAR gene promoter activity correlated with the differential expression of CAR mRNA levels from several urogenital cancer cell lines, indicating that the down-regulation of CAR gene expression is mediated by transcriptional regulation. It is known that epigenetic control, such as DNA methylation and histone acetylation of chromatin structure, dictates gene expression. Data from this study indicate that the activation of the CAR gene promoter is modulated by histone acetylation, but not by DNA methylation, in urogenital cancer cells. Also, a potent cancer chemotherapeutic agent (FR901228), a histone deacetylase inhibitor, was able to induce endogenous CAR gene expression in several urogenital cancer cells. Taken together, epigenetic control of CAR gene underlies the down-regulation of this gene in urogenital cancers.


Asunto(s)
Carcinoma de Células Transicionales/genética , Regulación Neoplásica de la Expresión Génica , Receptores Virales/genética , Neoplasias de la Vejiga Urinaria/genética , Secuencia de Bases , Carcinoma de Células Transicionales/metabolismo , Línea Celular Tumoral , Clonación Molecular , Proteína de la Membrana Similar al Receptor de Coxsackie y Adenovirus , Humanos , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Receptores Virales/biosíntesis , Neoplasias de la Vejiga Urinaria/metabolismo
20.
Cancer Res ; 64(4): 1425-30, 2004 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-14973053

RESUMEN

Laminin-5 (LN5) anchors epithelial cells to the underlying basement membrane, and it is encoded by three distinct genes: LAMA3, LAMB3, and LAMC2. To metastasize and grow, cancer cells must invade and destroy the basement membrane. Our previous work has shown that epigenetic inactivation is a major mechanism of silencing LN5 genes in lung cancers. We extended our methylation studies to resected bladder tumors (n = 128) and exfoliated cell samples (bladder washes and voided urine; n = 71) and correlated the data with clinicopathologic findings. Nonmalignant urothelium had uniform expression of LN5 genes and lacked methylation. The methylation frequencies for LN5 genes in tumors were 21-45%, and there was excellent concordance between methylation in tumors and corresponding exfoliated cells. Methylation of LAMA3 and LAMB3 and the methylation index were correlated significantly with several parameters of poor prognosis (tumor grade, growth pattern, muscle invasion, tumor stage, and ploidy pattern), whereas methylation of LAMC2 and methylation index were associated with shortened patient survival. Of particular interest, methylation frequencies of LAMA3 helped to distinguish invasive (72%) from noninvasive (12%) tumors. These results suggest that methylation of LN5 genes has potential clinical applications in bladder cancers.


Asunto(s)
Metilación de ADN , Laminina/genética , Regiones Promotoras Genéticas , Neoplasias de la Vejiga Urinaria/genética , Línea Celular Tumoral , Humanos , Invasividad Neoplásica , Metástasis de la Neoplasia , Pronóstico , Factores de Riesgo , Neoplasias de la Vejiga Urinaria/patología
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