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1.
Osteoporos Int ; 32(9): 1705-1712, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33594487

RESUMEN

The population-based cohort study used the Korean National Health Insurance claims database to evaluate the effect of anti-diabetic drugs on osteoporosis. The use of DPP-IV inhibitors does not increase the risk of osteoporosis compared with the use of sulfonylureas in patients with type 2 diabetes mellitus, while a weak association was found between thiazolidinediones and increased risk of osteoporosis. PURPOSE: The current study aimed to evaluate the effect of dipeptidyl peptidase IV inhibitors (DPP-IVi), thiazolidinedione (TZD), and sulfonylurea (SU) on osteoporosis in patients with type 2 diabetes. METHODS: A population-based cohort study was conducted in the Republic of Korea using the Korean National Health Insurance claims database. Data from 2012 to 2017 for patients of 50-99 years of age who were prescribed DPP-IVi, TZD, or SU during 2013-2015 were extracted from the database. Based on pre-defined criteria, a total of 381,404 patients were analyzed after inverse probability of treatment weighting. The association between the study drugs and osteoporosis was estimated using Cox proportional hazards models. Data of 220,166 patients who were prescribed DPP-IVi, 18,630 who were prescribed TZD, and 142,608 patients who were prescribed SU were set. RESULTS: In the multivariate-adjusted analysis, the hazard ratio (HR) of osteoporosis in the DPP-IVi group was not significantly different from that of the SU group (HR: 0.97; 95% confidence interval (CI) 0.94-1.00), whereas the HR of osteoporosis in the TZD group was higher (HR: 1.13; 95% CI 1.06-1.20). In the subgroup analysis, the HRs of osteoporosis were higher with pioglitazone (HR: 1.14; 95% CI 1.06-1.23) in the TZD group and with glibenclamides (HR: 1.39; 95% CI 1.09-1.77) in the SU group, whereas drugs with lower HR in the DPP-IVi group were saxagliptin (HR: 0.93; 95% CI 0.87-0.99) and sitagliptin (HR: 0.93; 95% CI 0.89-0.97). CONCLUSION: DPP-IV inhibitors do not increase the risk of osteoporosis compared with sulfonylureas in patients with type 2 diabetes mellitus, while a weak association was found between thiazolidinediones and increased risk of osteoporosis.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Osteoporosis , Tiazolidinedionas , Estudios de Cohortes , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/epidemiología , Inhibidores de la Dipeptidil-Peptidasa IV/efectos adversos , Humanos , Osteoporosis/inducido químicamente , Osteoporosis/tratamiento farmacológico , Osteoporosis/epidemiología , Tiazolidinedionas/efectos adversos
2.
Br J Cancer ; 110(6): 1420-6, 2014 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-24481403

RESUMEN

BACKGROUND: To evaluate the effects of elective nodal irradiation (ENI) in clinical stage II-III breast cancer patients with pathologically negative lymph nodes (LNs) (ypN0) after neoadjuvant chemotherapy (NAC) followed by breast-conserving surgery (BCS) and radiotherapy (RT). METHODS: We retrospectively analysed 260 patients with ypN0 who received NAC followed by BCS and RT. Elective nodal irradiation was delivered to 136 (52.3%) patients. The effects of ENI on survival outcomes were evaluated. RESULTS: After a median follow-up period of 66.2 months (range, 15.6-127.4 months), 26 patients (10.0%) developed disease recurrence. The 5-year locoregional recurrence-free survival and disease-free survival (DFS) for all patients were 95.5% and 90.5%, respectively. Pathologic T classification (0-is vs 1 vs 2-4) and the number of LNs sampled (<13 vs ≥13) were associated with DFS (P=0.0086 and 0.0012, respectively). There was no significant difference in survival outcomes according to ENI. Elective nodal irradiation also did not affect survival outcomes in any of the subgroups according to pathologic T classification or the number of LNs sampled. CONCLUSIONS: ENI may be omitted in patients with ypN0 breast cancer after NAC and BCS. But until the results of the randomised trials are available, patients should be put on these trials.


Asunto(s)
Neoplasias de la Mama/terapia , Ganglios Linfáticos/patología , Irradiación Linfática/métodos , Adulto , Anciano , Neoplasias de la Mama/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Ganglios Linfáticos/cirugía , Metástasis Linfática , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Estudios Retrospectivos , Adulto Joven
4.
Int J Clin Pharmacol Ther ; 49(11): 672-8, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22011692

RESUMEN

BACKGROUND: Sertraline is a naphthalenamine derivative which has the effect of selective serotonin reuptake inhibition. It has been used for major depression, and obsessive compulsive disorder. This study was performed to evaluate the pharmacokinetic (PK) characteristics after the administration of low dose sertraline for the purpose of exploring an application of microdosing methods in PK studies. METHODS: An open-label, three-period, single-sequence, dose-escalation study was performed in 6 healthy Korean male volunteers. Subjects were administered a single dose of 5 mg, 25 mg and 50 mg sertraline orally in each period, with 1 week washouts between periods. Blood samples were obtained up to 96 h after drug administration. Plasma concentrations were determined using high performance liquid chromatography-tandem mass spectrometry. PK parameters of sertraline were analyzed using non-compartmental methods. RESULTS: A total of 6 subjects completed the study. After the administration of sertraline at 5 mg, 25 mg and 50 mg, the median tmax were 6.0, 6.0 and 4.0 h and the mean (SD) elimination half-lives were 31.9 (6.5), 27.2 (6.7) and 28.0 (6.6) h, respectively. The AUC and Cmax increased dose-dependently. The dose-normalized mean (SD) AUC and Cmax were different in each dosing group (p < 0.01) with 2.0 (0.8), 5.3 (1.2) and 6.0 (1.9) mg × hr/l/mg in the 5 mg, 25 mg and 50 mg groups for dose-normalized AUC, and 0.07 (0.01), 0.18 (0.05) and 0.21 (0.08) mg/l/mg in the 5 mg, 25 mg and 50 mg groups for dose-normalized Cmax, respectively, which indicates a lack of dose proportionality. CONCLUSION: A lack of dose proportional properties was shown in the 5 mg dose relative to the 25 mg and 50 mg doses of sertraline. This shows that the PK parameters for low-dose sertraline could be different from those in clinical concentrations.


Asunto(s)
Inhibidores Selectivos de la Recaptación de Serotonina/farmacocinética , Sertralina/farmacocinética , Adulto , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Humanos , Corea (Geográfico) , Masculino , Persona de Mediana Edad , Sertralina/efectos adversos , Adulto Joven
5.
Ann Oncol ; 20(1): 56-62, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18664558

RESUMEN

BACKGROUND: Although trastuzumab therapy improves survival in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer, 40% of patients develop brain metastasis (BM) even when extracranial disease is under control. We studied whether trastuzumab therapy beyond or after BM was beneficial to patients with BM. PATIENTS AND METHODS: The effect of trastuzumab on survival after BM was analyzed in 78 HER2-positive breast cancer patients. Patients were grouped according to trastuzumab therapy; no treatment and treatment before and after BM were diagnosed. RESULTS: Overall survival after the diagnosis of BM as well as time to progression (TTP) of intracranial tumors was prolonged in patients who received trastuzumab after BM was diagnosed. Conversely, BM occurred much later in patients who received trastuzumab before BM. In the multivariate Cox regression model, age at BM <50 years, disease-free interval >or=24 months, TTP of intracranial tumor >or=4.8 months, and trastuzumab treatment after BM were significantly associated with longer survival after the onset of BM. CONCLUSIONS: Trastuzumab therapy after the onset of BM in HER2-positive breast cancer patients is associated with a significant survival benefit after BM diagnosis compared with patients who never received or completed trastuzumab before the BM diagnosis.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/secundario , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma/tratamiento farmacológico , Receptor ErbB-2/metabolismo , Adulto , Anciano , Algoritmos , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales Humanizados , Antineoplásicos/farmacología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidad , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Carcinoma/metabolismo , Carcinoma/mortalidad , Carcinoma/patología , Progresión de la Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Receptor ErbB-2/genética , Estudios Retrospectivos , Análisis de Supervivencia , Trastuzumab , Resultado del Tratamiento
6.
J Dent Res ; 98(10): 1150-1158, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31340691

RESUMEN

Oral mucosa provides the first line of defense against a diverse array of environmental and microbial irritants by forming the barrier of epithelial cells interconnected by multiprotein tight junctions (TJ), adherens junctions, desmosomes, and gap junction complexes. Grainyhead-like 2 (GRHL2), an epithelial-specific transcription factor, may play a role in the formation of the mucosal epithelial barrier, as it regulates the expression of the junction proteins. The current study investigated the role of GRHL2 in the Porphyromonas gingivalis (Pg)-induced impairment of epithelial barrier functions. Exposure of human oral keratinocytes (HOK-16B and OKF6 cells) to Pg or Pg-derived lipopolysaccharides (Pg LPSs) led to rapid loss of endogenous GRHL2 and the junction proteins (e.g., zonula occludens, E-cadherin, claudins, and occludin). GRHL2 directly regulated the expression levels of the junction proteins and the epithelial permeability for small molecules (e.g., dextrans and Pg bacteria). To explore the functional role of GRHL2 in oral mucosal barrier, we used a Grhl2 conditional knockout (KO) mouse model, which allows for epithelial tissue-specific Grhl2 KO in an inducible manner. Grhl2 KO impaired the expression of the junction proteins at the junctional epithelium and increased the alveolar bone loss in the ligature-induced periodontitis model. Fluorescence in situ hybridization revealed increased epithelial penetration of oral bacteria in Grhl2 KO mice compared with the wild-type mice. Also, blood loadings of oral bacteria (e.g., Bacteroides, Bacillus, Firmicutes, ß-proteobacteria, and Spirochetes) were significantly elevated in Grhl2 KO mice compared to the wild-type littermates. These data indicate that Pg bacteria may enhance paracellular penetration through oral mucosa in part by targeting the expression of GRHL2 in the oral epithelial cells, which then impairs the epithelial barrier by inhibition of junction protein expression, resulting in increased alveolar tissue destruction and systemic bacteremia.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Mucosa Bucal/microbiología , Porphyromonas gingivalis/patogenicidad , Uniones Estrechas , Factores de Transcripción/metabolismo , Animales , Células Cultivadas , Células Epiteliales , Humanos , Hibridación Fluorescente in Situ , Ratones , Ratones Noqueados , Factores de Transcripción/genética
7.
J Dent Res ; 97(7): 795-802, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29443638

RESUMEN

High-risk human papillomavirus (HPV) is a major risk factor for oral and pharyngeal cancers (OPCs), yet the detailed mechanisms by which HPV promotes OPCs are not understood. Forkhead box M1B (FoxM1B) is an oncogene essential for cell cycle progression and tumorigenesis, and it is aberrantly overexpressed in many tumors. We previously showed that FoxM1B was the putative target of an epithelial-specific transcription factor, Grainyhead-like 2 (GRHL2). In the current study, we demonstrate that HPV type 16 (HPV-16) E6 induces FoxM1B in human oral keratinocytes (HOKs) and tonsillar epithelial cells (TECs) in part through GRHL2. FoxM1B was barely detectable in cultured normal human oral keratinocytes (NHOKs) and progressively increased in immortalized HOKs harboring HPV-16 genome (HOK-16B) and tumorigenic HOK-16B/BaP-T cells. Retroviral expression of HPV-16 E6 and/or E7 in NHOKs, TECs, and hypopharyngeal carcinoma cells (FaDu) revealed induction of FoxM1B and GRHL2 by the E6 protein but not E7. Both GRHL2 and FoxM1B were strongly induced in the epidermis of HPV-16 E6 transgenic mice and HPV+ oral squamous cell carcinomas. Ectopic expression of FoxM1B led to acquisition of transformed phenotype in HOK-16B cells. Loss of FoxM1B by lentiviral short hairpin RNA vector or chemical inhibitor led to elimination of tumorigenic characteristics of HOK-16B/BaP-T cells. Luciferase reporter assay revealed that GRHL2 directly bound and regulated the FoxM1B gene promoter activity. Using epithelial-specific Grhl2 conditional knockout mice, we exposed wild-type (WT) and Grhl2 KO mice to 4-nitroquinolin 1-oxide (4-NQO), which led to induction of FoxM1B in the tongue tissues and rampant oral tumor development in the WT mice. However, 4-NQO exposure failed to induce tongue tumors or induction of FoxM1B expression in Grhl2 KO mice. Collectively, these results indicate that HPV-16 induces FoxM1B in part through GRHL2 transcriptional activity and that elevated FoxM1B level is required for oropharyngeal cancer development.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Células Epiteliales/metabolismo , Proteína Forkhead Box M1/metabolismo , Queratinocitos/metabolismo , Proteínas Oncogénicas Virales/fisiología , Neoplasias Orofaríngeas/virología , Proteínas Represoras/fisiología , Factores de Transcripción/fisiología , Animales , Western Blotting , Carcinogénesis/metabolismo , Línea Celular Tumoral , Modelos Animales de Enfermedad , Técnicas de Inactivación de Genes , Humanos , Inmunohistoquímica , Tonsila Palatina/citología , Infecciones por Papillomavirus/virología , Reacción en Cadena de la Polimerasa , Células Tumorales Cultivadas
8.
J Dent Res ; 96(1): 107-115, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28033065

RESUMEN

Direct pulp capping involves the placement of dental materials directly onto vital pulp tissues after deep caries removal to stimulate the regeneration of reparative dentin. This physical barrier will serve as a "biological seal" between these materials and the pulp tissue. Although numerous direct pulp capping materials are available, the use of small bioactive compounds that can potently stimulate and expedite reparative dentin formation is still underexplored. Here, the authors compared and evaluated the pro-osteogenic and pro-odontogenic effects of 4 small bioactive compounds- phenamil (Phen), purmorphamine (Pur), genistein (Gen), and metformin (Met). The authors found that these compounds at noncytotoxic concentrations induced differentiation and mineralization of preosteoblastic MC3T3-E1 cells and preodontoblastic dental pulp stem cells (DPSCs) in a dose-dependent manner. Among them, Phen consistently and potently induced differentiation and mineralization in vitro. A single treatment with Phen was sufficient to enhance the mineralization potential of DPSCs in vitro. More importantly, Phen-treated DPSCs showed enhanced odontogenic differentiation and mineralization in vivo. Our study suggests that these small bioactive compounds merit further study for their potential clinical use as pulp capping materials.


Asunto(s)
Amilorida/análogos & derivados , Calcificación Fisiológica/efectos de los fármacos , Genisteína/farmacología , Metformina/farmacología , Morfolinas/farmacología , Odontogénesis/efectos de los fármacos , Purinas/farmacología , Amilorida/farmacología , Animales , Pulpa Dental/citología , Pulpa Dental/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Ratones , Ratones Desnudos , Trasplante de Células Madre/métodos
9.
Clin Pharmacol Ther ; 102(3): 537-546, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28214288

RESUMEN

14 C-labeled YH4808, a novel potassium-competitive acid blocker, was intravenously administered as a microtracer at 80 µg (11.8 kBq or 320 nCi) concomitantly with the nonradiolabeled oral drug at 200 mg to determine the absolute bioavailability and to assess the effect of pharmacogenomics on the oral absorption of YH4808. The absolute bioavailability was low and highly variable (mean, 10.1%; range, 2.3-19.3%), and M3 and M8, active metabolites of YH4808, were formed 22.6- and 38.5-fold higher after oral administration than intravenous administration, respectively. The product of the fraction of an oral YH4808 dose entering the gut wall and the fraction of YH4808 passing on to the portal circulation was larger in subjects carrying the variants of the CHST3, SLC15A1, and SULT1B1 genes. A combined LC+AMS is a useful tool to construct a rich and highly informative pharmacokinetic knowledge core in early clinical drug development at a reasonable cost.


Asunto(s)
Antiulcerosos/administración & dosificación , Diseño de Fármacos , Espectrometría de Masas/métodos , Farmacogenética , Bloqueadores de los Canales de Potasio/administración & dosificación , Administración Intravenosa , Administración Oral , Adulto , Antiulcerosos/farmacocinética , Disponibilidad Biológica , Radioisótopos de Carbono , Humanos , Masculino , Bloqueadores de los Canales de Potasio/farmacocinética
10.
Clin Transl Sci ; 10(3): 163-171, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27785887

RESUMEN

To explore potential biomarkers for amoxicillin/clavulanate-induced liver injury (AC-DILI), we conducted a clinical trial in 32 healthy subjects based on multi-omics approaches. Every subject was administered amoxicillin/clavulanate for 14 days. The liver-specific microRNA-122 (miR-122) level increased prior to and correlated well with the observed alanine aminotransferase (ALT) level increase. This result indicates its potential as a sensitive early marker for AC-DILI. We also identified urinary metabolites, such as azelaic acid and 7-methylxanthine, with levels that significantly differed among the groups classified by ALT elevation level on day 8 after drug administration (P < 0.05). Lymphocyte proliferation in response to the drug was also observed. These findings demonstrate sequential changes in the process of AC-DILI, including metabolic changes, increased miR-122 level, increased liver enzyme activity, and enhanced lymphocyte proliferation after drug administration. In conclusion, this study provides potential biomarkers for AC-DILI based on currently known mechanisms using comprehensive multi-omics approaches.


Asunto(s)
Amoxicilina/efectos adversos , Biomarcadores/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Ácido Clavulánico/efectos adversos , Adulto , Alanina Transaminasa/sangre , Amoxicilina/farmacocinética , Biomarcadores/sangre , Biomarcadores/orina , Proliferación Celular , Enfermedad Hepática Inducida por Sustancias y Drogas/sangre , Enfermedad Hepática Inducida por Sustancias y Drogas/orina , Ácido Clavulánico/farmacocinética , Demografía , Humanos , Linfocitos/metabolismo , Masculino , Metaboloma , MicroARNs/sangre , Factores de Tiempo
11.
Cancer Res ; 61(9): 3541-3, 2001 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-11325814

RESUMEN

Autosomal dominant disorders of skeletal and cranial development have been linked to fibroblast growth factor receptor (FGFR) 2 and FGFR3. Here we report two identical mutations in FGFR2 that cause craniosynostosis syndromes, Crouzon, Apert, and Pfeiffer in gastric carcinoma. A missense mutation (Ser267Pro) in exon IIIa and a splice site mutation (940-2A-->G) in exon IIIc were detected in gastric cancer patients. Interestingly, these heterozygous somatic mutations are identical to the germinal activating mutations in FGFR2 reported previously in craniosynostosis syndromes. In addition, the two novel mutations of FGFR3 in colorectal carcinomas were identified. All identified mutations occurred at highly conserved sequences, not only in the FGFR family of molecules, but also throughout evolution and clustered in the immunoglobulin-like loop-III domain, highlighting the functional importance of this domain. Our results indicate that FGFR2 and FGFR3, in addition to their potential role in skeletal dysplasias, play an important role in tumorigenesis.


Asunto(s)
Neoplasias Colorrectales/genética , Mutación Missense , Proteínas Tirosina Quinasas , Proteínas Tirosina Quinasas Receptoras/genética , Receptores de Factores de Crecimiento de Fibroblastos/genética , Neoplasias Gástricas/genética , Secuencia de Aminoácidos , Animales , Secuencia Conservada , Craneosinostosis/genética , Humanos , Ratones , Datos de Secuencia Molecular , Ratas , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos
12.
Cancer Res ; 53(20): 4811-6, 1993 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-8402666

RESUMEN

We previously immortalized human oral keratinocytes by transfection with recombinant human papillomavirus type 16 (HPV-16) DNA and established two cell lines. These transfected cells were morphologically different from the normal counterpart, contained intact HPV-16 DNA in an integrated form, and expressed numerous viral genes. These cells contained lower levels of wild-type p53 protein and higher levels of c-myc mRNAs compared to normal cells. However, they proliferated only in keratinocyte growth medium containing a low level of calcium and were not tumorigenic in nude mice. A HPV-16-immortalized cell line was exposed to either 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone or N-methyl-N'-nitro-N-nitrosoguanidine. Four chemically transformed cell colonies were isolated. These cells proliferated well in Dulbecco's minimum essential medium containing a physiological level of calcium. They contained, similar to the immortalized counterpart, integrated HPV-16 sequences and lower levels of both wild-type p53 protein and DCC messages compared to normal cells. Among the chemically transformed cells, two colonies obtained from 4-(methyl-nitrosamino)-1-(3-pyridyl)-1-butanone exposure demonstrated an enhanced proliferation capacity in nude mice and transcribed a substantially higher amount of HPV-16 E6/E7, epidermal growth factor receptors, and c-myc genes compared with the immortalized counterpart. These experiments indicate that malignant transformation of oral keratinocytes can be caused by a sequential combined effect of "high risk" HPV and tobacco-related carcinogens.


Asunto(s)
Carcinógenos/toxicidad , Transformación Celular Neoplásica , Queratinocitos/citología , Metilnitronitrosoguanidina/toxicidad , Neoplasias de la Boca/etiología , Nicotiana , Nitrosaminas/toxicidad , Papillomaviridae , Plantas Tóxicas , Secuencia de Bases , División Celular , Línea Celular Transformada , Células Cultivadas , Neoplasias del Colon/genética , Cartilla de ADN , Receptores ErbB/genética , Exones , Genes myc , Genes p53 , Genes ras , Humanos , Queratinocitos/efectos de los fármacos , Masculino , Datos de Secuencia Molecular , Neoplasias de la Boca/inducido químicamente , Neoplasias de la Boca/microbiología , Mutagénesis , Oligonucleótidos Antisentido , Reacción en Cadena de la Polimerasa , Factor de Crecimiento Transformador alfa/genética
13.
Cancer Res ; 60(15): 4049-52, 2000 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-10945607

RESUMEN

A nested reverse transcription-PCR analysis of FGFR3 from human colorectal carcinomas revealed novel mutant transcripts caused by aberrant splicing and activation of cryptic splice sequences. Two aberrantly spliced transcripts were detected with high frequency in 50% of 36 primary tumors and in 60% of 10 human colorectal cancer cell lines. Most transcripts used normal splice sites but skipped or included exons 8 and 9. Two mutant transcripts arose from cryptic splice donor sites in exon 7 that spliced to exon 10. The predicted translation products would exhibit frameshifts and a premature termination codon in exon 10. We propose that dysregulation of mRNA splicing frequently generates an aberrant FGFR3 transcript that may confer a selectable advantage on clones of cells in colorectal tumorigenesis.


Asunto(s)
Empalme Alternativo/genética , Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Tirosina Quinasas , ARN Mensajero/genética , Receptores de Factores de Crecimiento de Fibroblastos/genética , Secuencia de Aminoácidos , Codón sin Sentido , Neoplasias Colorrectales/metabolismo , Regulación hacia Abajo , Exones/genética , Mutación del Sistema de Lectura , Humanos , Datos de Secuencia Molecular , Terminación de la Cadena Péptídica Traduccional , ARN Mensajero/metabolismo , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento de Fibroblastos/biosíntesis , Células Tumorales Cultivadas
14.
Nat Commun ; 7: 12655, 2016 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-27573030

RESUMEN

The presence of a di-unsaturated highly branched isoprenoid (HBI) lipid biomarker (diene II) in Southern Ocean sediments has previously been proposed as a proxy measure of palaeo Antarctic sea ice. Here we show that a source of diene II is the sympagic diatom Berkeleya adeliensis Medlin. Furthermore, the propensity for B. adeliensis to flourish in platelet ice is reflected by an offshore downward gradient in diene II concentration in >100 surface sediments from Antarctic coastal and near-coastal environments. Since platelet ice formation is strongly associated with super-cooled freshwater inflow, we further hypothesize that sedimentary diene II provides a potentially sensitive proxy indicator of landfast sea ice influenced by meltwater discharge from nearby glaciers and ice shelves, and re-examination of some previous diene II downcore records supports this hypothesis. The term IPSO25-Ice Proxy for the Southern Ocean with 25 carbon atoms-is proposed as a proxy name for diene II.

15.
Oncogene ; 12(5): 1089-96, 1996 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-8649801

RESUMEN

HPV-immortalized human oral keratinocytes can convert to tumorigenic cells when exposed to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), but normal human oral keratinocytes cannot transform with a similar exposure. The different responses of these cells could be due to different genetic stability of cells. In as much as genetic stability is determined by cell cycle control and of repair of damaged DNA, we studied the effect of MNNG exposure upon cell cycle progression, expression of p53, WAF1/CIP1 and gadd45, and the mutation frequency of a shuttle vector pS189 in normal human oral keratinocytes, in HPV-immortalized oral keratinocytes, and in an oral cancer cell line expressing mutant p53. Normal cells demonstrated transient cell cycle arrest after exposure to MNNG, but the other tested cells did not. While MNNG exposure significantly increased the levels of intranuclear wt p53 protein and the expression of WAF1/CIP1 and gadd45 genes in normal cells, it did not alter them in the immortalized and cancer cells. The mutation frequency of pS189 plasmid was significantly lower in normal cells than in the other tested cells. These data indicate that malignant conversion of HPV-immortalized oral keratinocytes may, in part, be associated with the cells' genetic instability. The genetic instability may be due to cells' (1) inability to accumulate intranuclear wt p53 to a threshold level at which p53 upregulates the transcription of WAF1/CIP1 and gadd45, resulting in the loss of cell cycle control and (2) inefficient repair of DNA damage caused by genotoxic agents.


Asunto(s)
Carcinógenos/toxicidad , Ciclinas/efectos de los fármacos , Daño del ADN , Queratinocitos/efectos de los fármacos , Metilnitronitrosoguanidina/toxicidad , Papillomaviridae , Proteínas/efectos de los fármacos , Proteína p53 Supresora de Tumor/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Transformada , Núcleo Celular/metabolismo , Transformación Celular Neoplásica , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/metabolismo , Vectores Genéticos/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular , Queratinocitos/metabolismo , Boca/citología , Mutación Puntual , Proteínas/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/metabolismo , Regulación hacia Arriba , Proteinas GADD45
16.
Oncogene ; 9(7): 1819-27, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8208528

RESUMEN

We previously demonstrated neoplastic conversion of HPV-immortalized human oral keratinocytes by exposing cells to chemical carcinogens, but failed to transform normal human oral keratinocytes with same chemical carcinogens in vitro. Though the reason for different responses of normal and HPV-immortalized oral keratinocytes to chemical carcinogens remains speculative, the difference may be due to the capacity of normal cells and incapacity of HPV-immortalized cells for repairing damaged DNA induced by carcinogens. Since (1) the repair of damaged DNA takes place in G1/G2 phases of cell cycle, (2) wild type p53 plays major role in the induction of transient G1 and/or G2 arrests, and (3) the expression of gadd45 and gadd153 is also associated with the cell cycle arrest and DNA damage, we investigated transient cell cycle arrest and the expression of p53, gadd45 and gadd153 in normal human oral keratinocytes, HPV-immortalized oral keratinocytes, and an oral cancer cell line expressing mutant p53 after exposing cells to UV light. Normal cells demonstrated transient G1 arrest after exposure to UV light, but other tested cells did not. While UV-irradiation significantly increased the level of intranuclear wild type p53 protein in normal cells, it did not alter p53 protein levels in HPV-immortalized and oral cancer cells. The level of gadd45 transcripts was enhanced in all tested cells, but normal cells demonstrated higher increase in the level of gadd45 after UV-exposure compared to other tested cells. The level of gadd153 gene transcripts was only increased in normal oral keratinocytes after UV-irradiation. These data indicate that UV-induced transient G1 arrest in normal oral keratinocytes may be associated with both enhanced levels of intranuclear wild type p53 protein and gadd45 and gadd153 transcripts.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT , Regulación de la Expresión Génica/efectos de la radiación , Genes p53 , Queratinocitos/efectos de la radiación , Proteínas/genética , Factores de Transcripción , Rayos Ultravioleta , Northern Blotting , Western Blotting , Ciclo Celular/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Transformación Celular Viral , Células Cultivadas , Daño del ADN , Técnica del Anticuerpo Fluorescente , Humanos , Péptidos y Proteínas de Señalización Intracelular , Queratinocitos/patología , Boca/citología , Papillomaviridae/fisiología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factor de Transcripción CHOP , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/efectos de la radiación , Proteinas GADD45
17.
Oncogene ; 10(11): 2145-53, 1995 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-7784058

RESUMEN

We previously immortalized normal human oral keratinocytes by transfection with recombinant HPV-16 DNA and subsequently exposed the cells to benzo(a)pyrene for 7 days. The exposure to benzo(a)pyrene modified the immortalized cells: the modified cells (HOK-16B-BaP) proliferated in an ordinary culture medium containing physiological calcium level (1.5 mM), but demonstrated only enhanced proliferation capacity without tumor formation in nude mice and failed to show in vitro anchorage-independency. In this study, we further modified the HOK-16B-BaP cells by subculturing the cells in a medium containing benzo(a)pyrene for 6 months. The cells were further modified with a chronic benzo(a)pyrene exposure and were termed HOK-16B-BaP-T cells (1) demonstrated a malignant phenotype in organotypic 'raft' culture, (2) showed in vitro anchorage-independency, (3) developed tumors in nude mice when injected subcutaneously, (4) contained a significantly higher copy number of intact and integrated HPV-16 DNA; (5) contained higher level of HPV-16 E6/E7 messages and E7 protein, (6) were more resistant to transforming growth factor-beta 1 and (7) secreted higher level of vascular endothelial growth factor with molecular weight of 56 kd than parental HOK-16B-BaP cells. However, the levels of p53 and ras proteins and the levels of p53, c-myc and c-fos transcripts in the HOK-16B-BaP-T cells were not different from those in the HOK-16B-BaP cells. The highly conserved coding regions of the p53, c-Ha-ras1, and c-Ki-ras2 genes of the tumor cells were not mutated. These data indicate that the HPV-immortalized human oral keratinocytes can convert to tumorigenic cells by chronic exposure to benzo(a)pyrene. The tumorigenic conversion seems to be associated with (1) the overexpression of viral oncogenes such as E6 and E7 genes, (2) the higher resistance of cells to transforming growth factor-beta 1 and (3) the high secretion of 56 kd vascular endothelial growth factor from the cells.


Asunto(s)
Benzo(a)pireno/toxicidad , Carcinoma de Células Escamosas/inducido químicamente , Carcinoma de Células Escamosas/virología , Cocarcinogénesis , Neoplasias de la Boca/etiología , Papillomaviridae/patogenicidad , Animales , Secuencia de Bases , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , División Celular/efectos de los fármacos , Línea Celular Transformada , Cartilla de ADN , ADN Viral/análisis , Factores de Crecimiento Endotelial/metabolismo , Genes fos , Genes myc , Genes ras , Humanos , Linfocinas/metabolismo , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Proteínas Oncogénicas Virales/genética , Papillomaviridae/genética , Proteínas E7 de Papillomavirus , ARN Viral/análisis , Factor de Crecimiento Transformador beta/farmacología , Proteína p53 Supresora de Tumor/genética , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
18.
Biochim Biophys Acta ; 1438(3): 399-407, 1999 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-10366782

RESUMEN

Tectorigenin and tectoridin, isolated from the rhizomes of Korean Belamcanda chinensis (Iridaceae) which are used as Chinese traditional medicine for the treatment of inflammation, suppressed prostaglandin E2 production by rat peritoneal macrophages stimulated by the protein kinase C activator, 12-O-tetradecanoylphorbol 13-acetate (TPA), or the endomembrane Ca2+-ATPase inhibitor, thapsigargin. Tectorigenin inhibited prostaglandin E2 production more potently than tectoridin. Neither compound inhibited the release of radioactivity from [3H]arachidonic acid-labeled macrophages stimulated by TPA or thapsigargin. In addition, activities of isolated cyclooxygenase (COX)-1 and COX-2 were not inhibited by the two compounds. Western blot analysis revealed that the induction of COX-2 by TPA or thapsigargin was inhibited by the two compounds in parallel with the inhibition of prostaglandin E2 production. These findings suggest that one of the mechanisms of the anti-inflammatory activities of the rhizomes of Belamcanda chinensis is the inhibition of prostaglandin E2 production by tectorigenin and tectoridin due to the inhibition of the induction of COX-2 in the inflammatory cells.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Dinoprostona/metabolismo , Medicamentos Herbarios Chinos/farmacología , Isoenzimas/biosíntesis , Isoflavonas/farmacología , Macrófagos Peritoneales/efectos de los fármacos , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Animales , Ácido Araquidónico/metabolismo , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Inducción Enzimática/efectos de los fármacos , Isoenzimas/análisis , Isoenzimas/metabolismo , Macrófagos Peritoneales/metabolismo , Masculino , Proteínas de la Membrana , Prostaglandina-Endoperóxido Sintasas/análisis , Prostaglandina-Endoperóxido Sintasas/metabolismo , Ratas , Ratas Sprague-Dawley , Acetato de Tetradecanoilforbol/antagonistas & inhibidores , Tapsigargina/antagonistas & inhibidores
19.
J Clin Oncol ; 8(9): 1543-55, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2167952

RESUMEN

A phase Ilate/II trial of hyperfractionated (HFX) radiation therapy for non-small-cell carcinoma of the lung (NSCCL) was conducted by the Radiation Therapy Oncology Group (RTOG) between 1983 and 1987. Fractions of 1.2 Gy were administered twice daily with greater than or equal to 4 hours between fractions. Patients were randomized to receive minimum total doses of 60.0, 64.8, and 69.6 Gy. After acceptable risks of acute and late effects were found, 74.4 Gy and 79.2 Gy arms were added, and the lowest total dose arms were closed. No significant differences in the risks of acute or late effects in normal tissues were found among the 848 patients analyzed in the five arms; risks of severe or life-threatening pneumonitis were 2.6% for 60.0 to 64.8 Gy, 5.7% for 69.6 to 74.4 Gy, and 8.1% for 79.2 Gy. Among 350 patients who had the same criteria as Cancer and Leukemia Group B (CALGB) protocol 84-33 (American Joint Committee on Cancer Staging [AJCCS], 1984, stage III; Karnofsky performance status [KPS] 70 to 100; less than 6% weight loss), there was a dose response for survival: survival with 69.6 Gy (median, 13.0 months; 2 years, 29%) was significantly (P = .02) better than the lower total doses. There were no differences in survival among the three highest total-dose arms. Comparisons with results in similar patients treated with 60 Gy in 30 fractions of 2.0 Gy 5 days per week for 6 weeks suggest benefit from HFX radiation therapy with 69.6 Gy. Improvement in survival with HFX radiation therapy at 69.6 Gy total dose without increase in normal tissue effects, justifies phase III comparison with standard fractionation alone and combined with systemic chemotherapy in this common presentation of NSCCL.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/radioterapia , Adulto , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Relación Dosis-Respuesta en la Radiación , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Traumatismos por Radiación/etiología , Dosificación Radioterapéutica , Ensayos Clínicos Controlados Aleatorios como Asunto
20.
Clin Cancer Res ; 6(2): 536-40, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10690536

RESUMEN

Somatic mutations in the transforming growth factor beta receptor type II (TGF-beta RII) gene have been observed in various human cancers showing microsatellite instability. Most of the mutations observed were additions or deletions of the mononucleotide repeat sequence present in TGF-beta RII coding region, suggesting that the TGF-beta RII may be a target gene of genomic instability in tumorigenesis. Recently, we reported germ-line frameshift mutations in the mononucleotide repeat sequence of the hMSH6 gene, which is believed to be one of the target genes of genomic instability in tumorigenesis, suggesting the possibility of germ-line mutation in mononucleotide repeat sequences. Moreover, one case of germ-line mutation in the TGF-beta RII gene was identified in a hereditary nonpolyposis colorectal cancer (HNPCC) kindred, indicating the involvement of TGF-beta RII inactivation in tumorigenesis of HNPCC. However, germ-line mutation analysis of all of the coding sequences and the mononucleotide repeat sequence of the TGF-beta RII in HNPCC patients has not yet been fully elucidated. Therefore, to further investigate the presence of germ-line mutations, we screened all of the coding region sequences and mononucleotide repeat sequence of TGF-beta RII from 35 HNPCC, 44 suspected HNPCC, and 45 sporadic early-onset colorectal cancer patients. However, no pathogenic mutations other than silent mutations, introgenic mutation, and polymorphisms were identified. Two silent mutations at codons 309 (ACG to ACA) and 340 (CAT to CAC) in the kinase domain located in exon 4 were detected. A 1-bp cytidine deletion was observed 6 bases from the 3' end of intron. Two polymorphisms were identified at codon 389 (AAC to AAT) and at the fourth-to-last base in intron 3. The polymorphism at codon 389 was more frequent in HNPCC (20%; 7 of 35) and suspected HNPCC patients (18%; 8 of 44) than in nonmalignant control group (10%; 5 of 50). Moreover, the frequency was significantly higher in early-onset colorectal cancer patients (31%; 14 of 45). This is the first report of a different frequency of polymorphism in HNPCC, suspected HNPCC, early-onset colorectal cancer patients, and healthy normal individuals. This result suggests that: (a) germ-line mutation of the TGF-beta RII gene may be a rare event during tumorigenesis in HNPCC and sporadic early-onset colorectal cancer; (b) the mononucleotide repeat sequence of the TGF-beta RII gene is an apparent target of genomic instability but not of germ-line mutation; and (c) the polymorphism of codon 389 (AAC to AAT) is frequent, especially in early-onset colorectal cancer patients, in which it is more frequent than in control group.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales/genética , Mutación , Polimorfismo Genético , Receptores de Factores de Crecimiento Transformadores beta/genética , Adulto , Edad de Inicio , Codón , Análisis Mutacional de ADN , ADN de Neoplasias/genética , Humanos , Corea (Geográfico) , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Proteínas Serina-Treonina Quinasas , Receptor Tipo II de Factor de Crecimiento Transformador beta , Secuencias Repetitivas de Ácidos Nucleicos
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