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1.
Angiogenesis ; 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483712

RESUMEN

Pathological retinal angiogenesis profoundly impacts visual function in vascular eye diseases, such as retinopathy of prematurity (ROP) in preterm infants and age-related macular degeneration in the elderly. While the involvement of photoreceptors in these diseases is recognized, the underlying mechanisms remain unclear. This study delved into the pivotal role of photoreceptors in regulating abnormal retinal blood vessel growth using an oxygen-induced retinopathy (OIR) mouse model through the c-Fos/A disintegrin and metalloprotease 17 (Adam17) axis. Our findings revealed a significant induction of c-Fos expression in rod photoreceptors, and c-Fos depletion in these cells inhibited pathological neovascularization and reduced blood vessel leakage in the OIR mouse model. Mechanistically, c-Fos directly regulated the transcription of Adam17 a shedding protease responsible for the production of bioactive molecules involved in inflammation, angiogenesis, and cell adhesion and migration. Furthermore, we demonstrated the therapeutic potential by using an adeno-associated virus carrying a rod photoreceptor-specific short hairpin RNA against c-fos which effectively mitigated abnormal retinal blood vessel overgrowth, restored retinal thickness, and improved electroretinographic (ERG) responses. In conclusion, this study highlights the significance of photoreceptor c-Fos in ROP pathology, offering a novel perspective for the treatment of this disease.

2.
J Exp Clin Cancer Res ; 42(1): 100, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37098540

RESUMEN

BACKGROUND: Small cell lung cancer (SCLC) is an aggressive neuroendocrine cancer with an appalling overall survival of less than 5% (Zimmerman et al. J Thor Oncol 14:768-83, 2019). Patients typically respond to front line platinum-based doublet chemotherapy, but almost universally relapse with drug resistant disease. Elevated MYC expression is common in SCLC and has been associated with platinum resistance. This study evaluates the capacity of MYC to drive platinum resistance and through screening identifies a drug capable of reducing MYC expression and overcoming resistance. METHODS: Elevated MYC expression following the acquisition of platinum resistance in vitro and in vivo was assessed. Moreover, the capacity of enforced MYC expression to drive platinum resistance was defined in SCLC cell lines and in a genetically engineered mouse model that expresses MYC specifically in lung tumors. High throughput drug screening was used to identify drugs able to kill MYC-expressing, platinum resistant cell lines. The capacity of this drug to treat SCLC was defined in vivo in both transplant models using cell lines and patient derived xenografts and in combination with platinum and etoposide chemotherapy in an autochthonous mouse model of platinum resistant SCLC. RESULTS: MYC expression is elevated following the acquisition of platinum resistance and constitutively high MYC expression drives platinum resistance in vitro and in vivo. We show that fimepinostat decreases MYC expression and that it is an effective single agent treatment for SCLC in vitro and in vivo. Indeed, fimepinostat is as effective as platinum-etoposide treatment in vivo. Importantly, when combined with platinum and etoposide, fimepinostat achieves a significant increase in survival. CONCLUSIONS: MYC is a potent driver of platinum resistance in SCLC that is effectively treated with fimepinostat.


Asunto(s)
Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Animales , Humanos , Ratones , Etopósido/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Recurrencia Local de Neoplasia , Fosfatidilinositol 3-Quinasas , Platino (Metal)/farmacología , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Carcinoma Pulmonar de Células Pequeñas/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo
3.
Radiother Oncol ; 182: 109588, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36858203

RESUMEN

BACKGROUND AND PURPOSE: Unexpected liver volume reductions occurred during trials of liver SBRT and concurrent sorafenib. The aims were to accumulate liver SBRT doses to assess the impact of these anatomic variations on normal tissue dose parameters and toxicity. MATERIALS AND METHODS: Thirty-two patients with hepatocellular carcinoma (HCC) or metastases treated on trials of liver SBRT (30-57 Gy, 6 fractions) and concurrent sorafenib were analyzed. SBRT doses were accumulated using biomechanical deformable registration of daily cone-beam CT. Dose deviations (accumulated-planned) for normal tissues were compared for patients with liver volume reductions > 100 cc versus stable volumes, and accumulated doses were reported for three patients with grade 3-5 luminal gastrointestinal toxicities. RESULTS: Patients with reduced (N = 12) liver volumes had larger mean deviations of 0.4-1.3 Gy in normal tissues, versus -0.2-0.4 Gy for stable cases (N = 20), P > 0.05. Deviations > 5% of the prescribed dose occurred in both groups. Two HCC patients with toxicities to small and large bowel had liver volume reductions and deviations to the maximum dose of 4% (accumulated 36.9 Gy) and 3% (accumulated 33.4 Gy) to these organs respectively. Another HCC patient with a toxicity of unknown location plus tumor rupture, had stable liver volumes and deviations to luminal organs of -6% to 4.5% (accumulated < 30.5 Gy). CONCLUSION: Liver volume reductions during SBRT and concurrent sorafenib were associated with larger increases in accumulated dose to normal tissues versus stable liver volumes. These dosimetric changes may have further contributed to toxicities in HCC patients who have higher baseline risks.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Radiocirugia , Humanos , Sorafenib/efectos adversos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Radiocirugia/efectos adversos , Dosificación Radioterapéutica
4.
Radiother Oncol ; 178: 109429, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36455685

RESUMEN

BACKGROUND: This study investigates the impact of dosimetric parameters on acute and late toxicity for patients with anal squamous cell carcinoma (SCC) treated with image-guided intensity modulated radiation therapy (IG-IMRT) and concurrent chemotherapy. MATERIALS AND METHODS: Patients were enrolled in an observational cohort study between 2008 and 2013 (median follow-up 3.4 years). They were treated with standardized target and organ-at-risk (OAR) contouring, planning, and IG-IMRT. Radiotherapy dose, based on clinicopathologic features, ranged from 45 Gy to 63 Gy to gross targets and 27 Gy to 36 Gy to elective targets. Chemotherapy was concurrent 5-fluorouracil and mitomycin C (weeks 1&5). Toxicity was prospectively graded using NCI CTCAE v.3 and RTOG scales. Logistic regression was used to assess the association between dose/volume parameters (e.g small bowel V5) and corresponding grade 2 + and 3+ (G2+/3 + ) toxicities (e.g. diarrhea). RESULTS: In total, 87 and 79 patients were included in the acute and late toxicity analyses, respectively. The most common acute G2 + toxicities were skin (dermatitis in 87 % [inguino-genital skin], 91 % [perianal skin]) and hematologic in 58 %. G2 + late anal toxicity (sphincter dysfunction), gastrointestinal toxicity, and skin toxicity were respectively experienced by 49 %, 38 %, and 44 % of patients. Statistically significant associations were observed between: G2 + acute diarrhea and small bowel V35; G2 + acute genitourinary toxicity and bladder D0.5cc; G2 + inguino-genital skin toxicity and anterior skin V35; G2 + perianal skin toxicity and posterior skin V15; G2 + anemia and lower pelvis bone V45. D0.5 cc was significantly predictive of late toxicity (G2 + anal dysfunction, intestinal toxicity, and inguino-genital/perianal dermatitis). Maximum skin toxicity grade was significantly correlated with the requirement for a treatment break. CONCLUSION: Statistically significant dose-volume parameters were identified and may be used to offer individualized risk prediction and to inform treatment planning. Additional validation of the results is required.


Asunto(s)
Neoplasias del Ano , Dermatitis , Radioterapia de Intensidad Modulada , Humanos , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Fluorouracilo/efectos adversos , Mitomicina/efectos adversos , Diarrea/etiología , Neoplasias del Ano/tratamiento farmacológico , Dermatitis/tratamiento farmacológico , Dermatitis/etiología , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
5.
Elife ; 112022 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-36149056

RESUMEN

Fibroblasts produce the majority of collagen in the heart and are thought to regulate extracellular matrix (ECM) turnover. Although fibrosis accompanies many cardiac pathologies and is generally deleterious, the role of fibroblasts in maintaining the basal ECM network and in fibrosis in vivo is poorly understood. We genetically ablated fibroblasts in mice to evaluate the impact on homeostasis of adult ECM and cardiac function after injury. Fibroblast-ablated mice demonstrated a substantive reduction in cardiac fibroblasts, but fibrillar collagen and the ECM proteome were not overtly altered when evaluated by quantitative mass spectrometry and N-terminomics. However, the distribution and quantity of collagen VI, microfibrillar collagen that forms an open network with the basement membrane, was reduced. In fibroblast-ablated mice, cardiac function was better preserved following angiotensin II/phenylephrine (AngII/PE)-induced fibrosis and myocardial infarction (MI). Analysis of cardiomyocyte function demonstrated altered sarcomere shortening and slowed calcium decline in both uninjured and AngII/PE-infused fibroblast-ablated mice. After MI, the residual resident fibroblasts responded to injury, albeit with reduced proliferation and numbers immediately after injury. These results indicate that the adult mouse heart tolerates a significant degree of fibroblast loss with a potentially beneficial impact on cardiac function after injury. The cardioprotective effect of controlled fibroblast reduction may have therapeutic value in heart disease.


Asunto(s)
Infarto del Miocardio , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas , Angiotensina II , Animales , Calcio/farmacología , Colágeno , Fibroblastos , Fibrosis , Ratones , Infarto del Miocardio/patología , Miocardio/patología , Fenilefrina/farmacología , Proteoma
6.
Nutrients ; 14(13)2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35807870

RESUMEN

Currently, there is no global consensus about the essentiality of dietary chromium. To provide evidence to this debate, an examination of blood chromium levels and common chronic health conditions was undertaken. Using a subsample from the 2015−2016 US National Health and Nutrition Examination Survey (n = 2894; 40 years+), chi-square and binary logistic regression analyses were conducted to examine blood chromium levels (0.7−28.0 vs. <0.7 µg/L) and their associations with cardiovascular diseases (CVDs; self-report), diabetes mellitus (DM; glycohemoglobin ≥5.7%), and depression (Patient Health Questionnaire-9 score ≥5), while controlling for socio-demographic (age/sex/income/education/relationship status) and health-related (red blood cell folate/medications/co-morbidities/body mass index (BMI)/substance use) factors. The sample was almost evenly distributed between men and women (n = 1391, 48.1% (men); n = 1503, 51.9% (women)). The prevalence estimates of low blood chromium levels tended to be higher among those with CVDs (47.4−47.6%) and DM (50.0−51.6%). Comparisons between those with low vs. normal blood chromium levels indicate men have increased odds of CVDs (adjusted odds ratio (aOR) = 1.86, 95% confidence interval (CI): 1.22−2.85, p < 0.001) and DM (aOR = 1.93, 95% CI: 1.32−2.83, p < 0.001) and lower odds of depression (aOR = 0.42, 95% CI: 0.22−0.77, p < 0.05). Dietary chromium may be important in the prevention and management of CVDs and DM for men. Continued exploration of chromium's role in chronic diseases, including differences by biological factors, is needed.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus , Enfermedades Cardiovasculares/epidemiología , Cromo , Depresión/epidemiología , Femenino , Humanos , Masculino , Encuestas Nutricionales , Prevalencia
7.
Cancer Lett ; 534: 215613, 2022 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-35276290

RESUMEN

Signal transducer and activator of transcription (Stat)3 is a valid anticancer therapeutic target. We have discovered a highly potent chemotype that amplifies the Stat3-inhibitory activity of lead compounds to levels previously unseen. The azetidine-based compounds, including H172 (9f) and H182, irreversibly bind to Stat3 and selectively inhibit Stat3 activity (IC50 0.38-0.98 µM) over Stat1 or Stat5 (IC50 > 15.8 µM) in vitro. Mass spectrometry detected the Stat3 cysteine peptides covalently bound to the azetidine compounds, and the key residues, Cys426 and Cys468, essential for the high potency inhibition, were confirmed by site-directed mutagenesis. In triple-negative breast cancer (TNBC) models, treatment with the azetidine compounds inhibited constitutive and ligand-induced Stat3 signaling, and induced loss of viable cells and tumor cell death, compared to no effect on the induction of Janus kinase (JAK)2, Src, epidermal growth factor receptor (EGFR), and other proteins, or weak effects on cells that do not harbor aberrantly-active Stat3. H120 (8e) and H182 as a single agent inhibited growth of TNBC xenografts, and H278 (hydrochloric acid salt of H182) in combination with radiation completely blocked mouse TNBC growth and improved survival in syngeneic models. We identify potent azetidine-based, selective, irreversible Stat3 inhibitors that inhibit TNBC growth in vivo.


Asunto(s)
Azetidinas , Neoplasias de la Mama Triple Negativas , Animales , Apoptosis , Azetidinas/farmacología , Línea Celular Tumoral , Humanos , Ratones , Fosforilación , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética
8.
Oncogene ; 41(1): 138-145, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34675406

RESUMEN

Small cell lung cancer (SCLC) is an aggressive neuroendocrine cancer characterized by loss of function TP53 and RB1 mutations in addition to mutations in other oncogenes including MYC. Overexpression of MYC together with Trp53 and Rb1 loss in pulmonary neuroendocrine cells of the mouse lung drives an aggressive neuroendocrine low variant subtype of SCLC. However, the transforming potential of MYC amplification alone on airway epithelium is unclear. Therefore, we selectively and conditionally overexpressed MYC stochastically throughout the airway or specifically in neuroendocrine, club, or alveolar type II cells in the adult mouse lung. We observed that MYC overexpression induced carcinoma in situ which did not progress to invasive disease. The formation of adenoma or SCLC carcinoma in situ was dependent on the cell of origin. In contrast, MYC overexpression combined with conditional deletion of both Trp53 and Rb1 exclusively gave rise to SCLC, irrespective of the cell lineage of origin. However, cell of origin influenced disease latency, metastatic potential, and the transcriptional profile of the SCLC phenotype. Together this reveals that MYC overexpression alone provides a proliferative advantage but when combined with deletion of Trp53 and Rb1 it facilitates the formation of aggressive SCLC from multiple cell lineages.


Asunto(s)
Neoplasias Pulmonares/genética , Oncogenes/fisiología , Proteína de Retinoblastoma/metabolismo , Carcinoma Pulmonar de Células Pequeñas/genética , Proteína p53 Supresora de Tumor/metabolismo , Animales , Humanos , Neoplasias Pulmonares/patología , Ratones , Carcinoma Pulmonar de Células Pequeñas/patología
9.
BMC Musculoskelet Disord ; 22(1): 499, 2021 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-34051761

RESUMEN

BACKGROUND: Surgical treatment of full-thickness rotator cuff (RC) tears is associated with generally good results. There is no consensus regarding treatment of partial thickness tears that fail conservative treatment. The purpose of this study was to look at the efficacy and confirm the safety of dual injection PRP into the shoulder of patients with rotator cuff pathology who have failed conservative treatment with followup to two years. METHODS: Seventy-one shoulders with MRI confirmed, rotator cuff pathology who failed conservative treatment, had dual PRP injection into the rotator cuff. Global improvement, Quick DASH and VAS scores were collected at 6, 12, and 24 months after treatment and comparison of means was used to analyze changes. RESULTS: No adverse events were seen in any patient. Based on global rating scores positive results were seen in 77.9 % of patients at 6 months, 71.6 % at 1 year, and 68.8 % of patients at 2 years. Mean VAS scores improved from 50.2 [CI 44.4-56.0] pre-injection to 26.2 [CI 19.5-32.9] at 6 months, 22.4[CI 16.1-28.7] at 1 year and 18.2 [CI 12.3-24.1] at 2 years (p < 0.0001 for all). The mean Q- DASH scores (0-100, 100 worse) improved from 39.2 [CI 34.3-44.1] for all patients before treatment to 20.7[CI 15.0-26.4] at 6 months, 18.0[CI 12.9-23.1] at 1 year, and 13.8 [CI 8.4-18.8] at 2 years (p < 0.0001 for all). No patient with partial tear had clinical evidence of progression to full thickness tear. When separated into subgroups based on rotator cuff status, all subgroups showed improvement. Patients in the > 50 % partial tear group had the best overall improvement based on Global Rating scores while those in the tendinitis group had the poorest outcomes. CONCLUSIONS: PRP injection is a safe and effective treatment for RC cuff injury in patients who have failed conservative treatment of activity modification and physical therapy without deterioration of results two years after treatment. Better results are obtained with greater structural tendon damage than in shoulders with inflammation without structural damage. TRIAL REGISTRATION: This is not a clinical trial.


Asunto(s)
Plasma Rico en Plaquetas , Lesiones del Manguito de los Rotadores , Estudios de Seguimiento , Humanos , Estudios Prospectivos , Manguito de los Rotadores/diagnóstico por imagen , Manguito de los Rotadores/cirugía , Lesiones del Manguito de los Rotadores/diagnóstico por imagen , Lesiones del Manguito de los Rotadores/cirugía
10.
J Med Chem ; 64(1): 695-710, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33352047

RESUMEN

We optimized our previously reported proline-based STAT3 inhibitors into an exciting new series of (R)-azetidine-2-carboxamide analogues that have sub-micromolar potencies. 5a, 5o, and 8i have STAT3-inhibitory potencies (IC50) of 0.55, 0.38, and 0.34 µM, respectively, compared to potencies greater than 18 µM against STAT1 or STAT5 activity. Further modifications derived analogues, including 7e, 7f, 7g, and 9k, that addressed cell membrane permeability and other physicochemical issues. Isothermal titration calorimetry analysis confirmed high-affinity binding to STAT3, with KD of 880 nM (7g) and 960 nM (9k). 7g and 9k inhibited constitutive STAT3 phosphorylation and DNA-binding activity in human breast cancer, MDA-MB-231 or MDA-MB-468 cells. Furthermore, treatment of breast cancer cells with 7e, 7f, 7g, or 9k inhibited viable cells, with an EC50 of 0.9-1.9 µM, cell growth, and colony survival, and induced apoptosis while having relatively weaker effects on normal breast epithelial, MCF-10A or breast cancer, MCF-7 cells that do not harbor constitutively active STAT3.


Asunto(s)
Azetidinas/química , Factor de Transcripción STAT3/antagonistas & inhibidores , Amidas/química , Apoptosis/efectos de los fármacos , Azetidinas/metabolismo , Azetidinas/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , ADN/química , ADN/metabolismo , Evaluación Preclínica de Medicamentos , Humanos , Concentración 50 Inhibidora , Fosforilación/efectos de los fármacos , Unión Proteica , Factor de Transcripción STAT3/metabolismo , Relación Estructura-Actividad
11.
Cancers (Basel) ; 11(11)2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31683879

RESUMEN

Medulloblastoma is the most common malignant brain tumor in children and represents 20% of all pediatric central nervous system neoplasms. While advances in surgery, radiation and chemotherapy have improved overall survival, the lifelong sequelae of these treatments represent a major health care burden and have led to ongoing efforts to find effective targeted treatments. There is a well-recognized male bias in medulloblastoma diagnosis, although the mechanism remains unknown. Herein, we identify a sex-specific role for the transcription factor Signal Transducer and Activator of Transcription 3 (STAT3) in the Sonic Hedgehog (SHH) medulloblastoma subgroup. Specific deletion of Stat3 from granule cell precursors in a spontaneous mouse model of SHH medulloblastoma completely protects male, but not female mice from tumor initiation. Segregation of SHH medulloblastoma patients into high and low STAT3 expressing cohorts shows that low STAT3 expression correlates with improved overall survival in male patients. We observe sex specific changes in IL-10 and IL-6 expression and show that IL-6 stimulation enhances SHH-mediated gene transcription in a STAT3-dependent manner. Together these data identify STAT3 as a key molecule underpinning the sexual dimorphism in medulloblastoma.

13.
Data Brief ; 12: 603-607, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28540352

RESUMEN

Galanin Receptor 3 (GALR3) is a G-protein-coupled receptor with a widespread distribution in the brain and plays a role in a variety of physiologic processes including cognition/memory, sensory/pain processing, hormone secretion, and feeding behavior. Therefore, GALR3 is considered an attractive CNS drug target (Freimann et al., 2015) [1]. This dataset contains GALR3 point mutants that improve recombinant protein expression and thermal stability of the receptor contained in virus-like particles (VLPs) or obtained by detergent-purification of baculovirus-infected insect cells. The mutations listed can be grouped in those that improve the stability of the agonist-bound and the antagonist-bound form of the receptor. Protein characteristics in terms of protein expression and thermal stability were comparable between GPCR-VLP and GPCR overexpressing Sf9 cultures. The further analysis and detailed results of these mutants as well as their impact on biophysical assay development for drug discovery can be found in "Method for Rapid Optimization of Recombinant GPCR Protein Expression and Stability using Virus-Like Particles" (Ho et al., 2017) [2].

14.
Protein Expr Purif ; 133: 41-49, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28263854

RESUMEN

Recent innovative approaches to stabilize and crystallize GPCRs have resulted in an unprecedented breakthrough in GPCR crystal structures as well as application of the purified receptor protein in biophysical and biochemical ligand binding assays. However, the protein optimization process to enable these technologies is lengthy and requires iterative overexpression, solubilization, purification and functional analysis of tens to hundreds of protein variants. Here, we report a new and versatile method to screen in parallel hundreds of GPCR variants in HEK293 produced virus-like particles (VLPs) for protein yield, stability, functionality and ligand binding. This approach reduces the time and resources during GPCR construct optimization by eliminating lengthy protein solubilization and purification steps and by its adaptability to many binding assay formats (label or label-free detection). We exemplified the robustness of our VLP method by screening 210 GALR3-VLP variants in a radiometric agonist-based binding assay and a subset of 88 variants in a label-free antagonist-based assay. The resulting GALR3 agonist or antagonist stabilizing variants were then further used for recombinant protein expression in transfected insect cells. The final purified protein variants were successfully immobilized on a biosensor chip and used in a surface plasmon resonance binding assay.


Asunto(s)
Expresión Génica , Receptor de Galanina Tipo 3 , Proteínas Recombinantes de Fusión , Virión , Células HEK293 , Humanos , Estabilidad Proteica , Receptor de Galanina Tipo 3/biosíntesis , Receptor de Galanina Tipo 3/química , Receptor de Galanina Tipo 3/genética , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Virión/química , Virión/genética , Virión/metabolismo
15.
J Med Imaging Radiat Sci ; 48(4): 352-359, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31047470

RESUMEN

PURPOSE: Online treatment setup verification through cone-beam computed tomography (CBCT) in pancreatic cancer patients is limited by low soft tissue contrast. This study aims to quantify the relative positional displacements between bony anatomy and endobiliary stents as surrogates for pancreatic cancers. METHODS: Under ethics approval, 258 localization CBCT images from 15 pancreatic patients with endobiliary stents were evaluated. CBCTs were registered through two methods to assess translations and rotations: target adjacent bony anatomy through automatic registration and automatic stent registration through a shaped region of interest. Displacement vector differences between surrogate registrations were calculated and analysed. RESULTS: Mean (±standard deviation) translational displacements in the right/left, superior/inferior, anterior/posterior directions were 0.9 ± 3.1 mm, 1.8 ± 4.2 mm, and 0.4 ± 2.5 mm for bone registrations, respectively, and 0.9 ± 5.6 mm, -1.5 ± 5.7 mm, and -0.5 ± 4.3 mm for stent registrations, respectively. Mean (±standard deviation) rotational displacements for pitch, roll, and yaw were 0.16 ± 0.97°, -0.32 ± 0.96°, and -0.77 ± 1.8° for bone registrations, respectively, and -0.94 ± 4.6°, -0.4 ± 7.4°, and -0.13 ± 6.64° for stent registrations, respectively. Mean displacement vector between surrogates was 4 mm, with 43% of fractions measuring displacement vectors >5 mm. A maximum displacement vector of 22.6 mm between surrogates was observed. CONCLUSIONS: Varying positional differences were observed between bone and stent registration for pancreas CBCT-image-guided radiation therapy. Setup errors for stent matching were larger than bone registrations. Further research is required to determine if endobiliary stent position is equivalent to the pancreas' location to determine its suitability as a surrogate.


Asunto(s)
Marcadores Fiduciales , Neoplasias Pancreáticas/radioterapia , Radioterapia Guiada por Imagen/métodos , Stents , Adulto , Anciano , Anciano de 80 o más Años , Conductos Biliares/cirugía , Huesos/anatomía & histología , Huesos/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/diagnóstico por imagen , Estudios Retrospectivos
16.
Clin Exp Pharmacol Physiol ; 42(5): 458-64, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25739318

RESUMEN

Enhancer of zeste 2 (EZH2), a polycomb histone methyltransferase, is overexpressed in various cancers, including cervical cancer. Gene expression analysis revealed that increased expression of EZH2 is associated with cervical cancer progression, particularly the progression to invasive squamous cell carcinoma. Enhancer of zeste 2 is known to trimethylate lysine 27 on histone H3, leading to gene silencing that contributes to the progression of tumours into a more aggressive form of cancer. However, the specific molecular mechanisms by which EZH2 contributes to the development of cervical cancer remain largely unknown. Recently, an EZH2 inhibitor was reported to selectively inhibit trimethylated lysine 27 on histone H3 and to reactivate silenced genes in cancer cells. In this study, we found that GSK343 (a specific inhibitor of EZH2 methyltransferase) induces phenotypic reprogramming of cancer cells from mesenchymal to epithelial cells, reducing proliferation and cell motility and blocking the invasion of cervical cancer cell lines both in vitro and in vivo. Treatment with the EZH2 inhibitor led to increased levels of the epithelial marker E-cadherin and decreased levels of mesenchymal markers such as N-cadherin and vimentin. The observed reprogramming is associated with restrained cervical cancer progression and provides direct evidence in support of EZH2 as a therapeutic target.


Asunto(s)
Terapia Molecular Dirigida , Complejo Represivo Polycomb 2/metabolismo , Neoplasias del Cuello Uterino/tratamiento farmacológico , Animales , Cadherinas/metabolismo , Carcinogénesis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proteína Potenciadora del Homólogo Zeste 2 , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HeLa , Humanos , Indazoles/farmacología , Indazoles/uso terapéutico , Ratones , Invasividad Neoplásica , Complejo Represivo Polycomb 2/agonistas , Complejo Represivo Polycomb 2/antagonistas & inhibidores , Piridonas/farmacología , Piridonas/uso terapéutico , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología , Ensayos Antitumor por Modelo de Xenoinjerto
17.
J Pharmacol Exp Ther ; 345(3): 438-45, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23532932

RESUMEN

The MDR1 gene encodes P-glycoprotein, a transmembrane drug efflux transporter that confers multidrug resistance in cancer cells and affects drug pharmacokinetics by virtue of its expression in the liver, kidney, and colon. Nuclear receptors human steroid and xenobiotic receptor (SXR) and constitutive androstane receptor (CAR) are possible master regulators of xenobiotic-inducible MDR1 expression in drug processing organs, but the mechanism of MDR1 regulation has yet to be directly demonstrated in vivo. Moreover, it has previously been impossible to determine the sustained or cumulative effect of repeated doses of xenobiotics on in vivo MDR1 expression. We previously reported a mouse model containing firefly luciferase (fLUC) knocked into the mdr1a genomic locus, allowing noninvasive bioimaging of intestinal mdr1a gene expression in live animals. In the current study, we crossed mdr1a.fLUC mice into the pxr knockout (pxr(-/-)) genetic background and injected mice with pregnenolone-16α-carbonitrile (PCN), a strong mouse pregnane X receptor (PXR) ligand, and two therapeutically relevant taxanes, paclitaxel and docetaxel. All three agents induced mdr1a.fLUC expression (bioluminescence), but only PCN and docetaxel appeared to act primarily via PXR. Luminescence returned to baseline by 24-48 hours after drug injection and was reinducible over two additional rounds of drug dosing in pxr(+/+) mice. TCPOBOP, a CAR ligand, modestly induced mdr1a.fLUC in pxr(+/+) and pxr(-/-) strains, consistent with CAR's minor role in mdr1a regulation. Collectively, these results demonstrate that the mdr1a.fLUC bioimaging model can capture changes in mdr1 gene expression under conditions of repeated xenobiotic treatment in vivo and that it can be used to probe the mechanism of gene regulation in response to different xenobiotic agents.


Asunto(s)
Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Genes Reporteros/genética , Luciferasas/genética , Receptores de Esteroides/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/efectos de los fármacos , Animales , Antineoplásicos Fitogénicos/farmacología , Receptor de Androstano Constitutivo , Docetaxel , Ácidos Grasos Monoinsaturados/farmacología , Expresión Génica/efectos de los fármacos , Genes Reporteros/efectos de los fármacos , Humanos , Procesamiento de Imagen Asistido por Computador , Mucosa Intestinal/metabolismo , Ligandos , Proteínas Luminiscentes/biosíntesis , Ratones , Ratones Noqueados , Paclitaxel/farmacología , Receptor X de Pregnano , Piridinas/farmacología , Compuestos de Amonio Cuaternario/farmacología , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores de Esteroides/efectos de los fármacos , Taxoides/farmacología , Xenobióticos/farmacología
18.
Glob J Health Sci ; 5(1): 1-12, 2012 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-23283031

RESUMEN

The Farage Quality of Life™ questionnaire (FQoL™) was developed specifically to assess the impact of consumer products. The objective of this investigation was to achieve a Chinese language instrument. The FQoL™ underwent a forward and backward translation, with cognitive testing by 13 subjects. Slight modifications were made to the instrument, and an implementation study was conducted with 800 participants having a mean (±SD) age of 34.22 (±9.28) years. The subjects were randomly assigned to use 1 of 4 ultra absorbency pad products for the length of one menstrual cycle. Three pads (coded N, S and C) were products currently available on the retail market, a fourth (coded M) was an experimental product improvement on Product N. Subjects were asked to complete the FQoL™ once before (T1) and once after (T2) the start of their period, and the Least Square (LS) Means were determined. Within group comparisons for each item and FQoL™ subscale were conducted by comparing the LS Means for T1 vs. T2. Participants using Product N showed the highest number of significant (p<0.05) changes (11 items), demonstrating these subjects felt worse about items mainly in the subdomains for Emotions, Personal Pleasure, and Physical State. Participants using Product C showed significant changes in 7 items mainly in the subdomains for Emotion and Physical State. Participants using Product S and the experimental Product M showed significant changes in only 4 and 3 individual items, respectively. These were not associated with any particular domain or subdomain. Between group comparisons were conducted by comparing the LS Means for the T2 responses for each group. The group using Product N had LS Mean responses that were significantly worse than the group using Product M for the Emotion, Personal Pleasure and Physical State subdomains, the Energy/Vitality domain, and 2 individual items. The Product S group was worse than the Product M group for 2 individual items. The Product C group was worse than the Product M group for the Personal Pleasure and Physical State subdomains and 5 individual items. We found that the Chinese language FQoL™ detected changes in HRQoL during menstruation compared with before menstruation. Further, the measure was able to detect differences among groups of subjects using different menstrual protection products.


Asunto(s)
Productos para la Higiene Menstrual , Menstruación/psicología , Psicometría/instrumentación , Calidad de Vida/psicología , Adolescente , Adulto , Análisis de Varianza , Niño , China , Comportamiento del Consumidor , Comparación Transcultural , Femenino , Humanos , Análisis de los Mínimos Cuadrados , Persona de Mediana Edad , Reproducibilidad de los Resultados , Traducciones , Estados Unidos , Adulto Joven
20.
Mol Endocrinol ; 17(6): 1005-18, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12677008

RESUMEN

Using a cDNA array consisting only of cell cycle genes, we found that a novel nonthiazolidinedione partial peroxisome proliferator-activated receptor gamma (PPARgamma) agonist (nTZDpa) inhibited expression of minichromosome maintenance (MCM) proteins 6 and 7 in vascular smooth muscle cells. MCM proteins are required for the initiation and elongation stages of DNA replication and are regulated by the transcription factor E2F. Mitogen-induced MCM6 and MCM7 mRNA expression was potently inhibited by nTZDpa and to a lesser degree by the full PPARgamma agonist, rosiglitazone. Inhibition of MCM6 and MCM7 expression by nTZDpa and rosiglitazone paralleled their effect to inhibit phosphorylation of the retinoblastoma protein and cell proliferation. Transient transfection experiments revealed that the nTZDpa inhibited mitogen-induced MCM6 and MCM7 promoter activity, implicating a transcriptional mechanism. Adenoviral-mediated E2F overexpression reversed the suppressive effect of nTZDpa on MCM6 and MCM7 expression. Furthermore, activity of a luciferase reporter plasmid driven by multiple E2F elements was inhibited by nTZDpa, indicating that their down-regulation by nTZDpa involves an E2F-dependent mechanism. Overexpression of dominant-negative PPARgamma or addition of a PPARgamma antagonist, GW 9662, blocked nTZDpa inhibition of MCM7 transcription. Adenovirus-mediated overexpression of constitutively active PPARgamma inhibited MCM7 expression in a similar manner as the nTZDpa. These findings provide strong evidence that activation of PPARgamma attenuates MCM7 transcription and support the important role of this nuclear receptor in regulating vascular smooth muscle cell proliferation.


Asunto(s)
Proteínas de Ciclo Celular/genética , Replicación del ADN/efectos de los fármacos , Proteínas de Unión al ADN/genética , Indoles/farmacología , Músculo Liso Vascular/efectos de los fármacos , Proteínas Nucleares/genética , Receptores Citoplasmáticos y Nucleares/agonistas , Sulfuros/farmacología , Tiazolidinedionas/farmacología , Factores de Transcripción/agonistas , Activación Transcripcional/efectos de los fármacos , Animales , Aorta/citología , Proteínas de Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Proteínas de Unión al ADN/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Técnicas In Vitro , Músculo Liso Vascular/metabolismo , Proteínas Nucleares/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Rosiglitazona , Fase S/efectos de los fármacos
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