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1.
J Integr Neurosci ; 23(7): 134, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39082284

RESUMEN

BACKGROUND: Sleep spindles have emerged as valuable biomarkers for assessing cognitive abilities and related disorders, underscoring the importance of their detection in clinical research. However, template matching-based algorithms using fixed templates may not be able to fully adapt to spindles of different durations. Moreover, inspired by the multiscale feature extraction of images, the use of multiscale feature extraction methods can be used to better adapt to spindles of different frequencies and durations. METHODS: Therefore, this study proposes a novel automatic spindle detection algorithm based on elastic time windows and spatial pyramid pooling (SPP) for extracting multiscale features. The algorithm utilizes elastic time windows to segment electroencephalogram (EEG) signals, enabling the extraction of features across multiple scales. This approach accommodates significant variations in spindle duration and polarization positioning during different EEG epochs. Additionally, spatial pyramid pooling is integrated into a depthwise separable convolutional (DSC) network to perform multiscale pooling on the segmented spindle signal features at different scales. RESULTS: Compared with existing template matching algorithms, this algorithm's spindle wave polarization positioning is more consistent with the real situation. Experimental results conducted on the public dataset DREAMS show that the average accuracy of this algorithm reaches 95.75%, with an average negative predictive value (NPV) of 96.55%, indicating its advanced performance. CONCLUSIONS: The effectiveness of each module was verified through thorough ablation experiments. More importantly, the algorithm shows strong robustness when faced with changes in different experimental subjects. This feature makes the algorithm more accurate at identifying sleep spindles and is expected to help experts automatically detect spindles in sleep EEG signals, reduce the workload and time of manual detection, and improve efficiency.


Asunto(s)
Algoritmos , Electroencefalografía , Humanos , Electroencefalografía/métodos , Fases del Sueño/fisiología , Procesamiento de Señales Asistido por Computador , Adulto
2.
J Integr Neurosci ; 22(6): 146, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-38176922

RESUMEN

BACKGROUND: In recent years, road traffic safety has become a prominent issue due to the worldwide proliferation of vehicles on roads. The challenge of driver fatigue detection involves balancing the efficiency and accuracy of the detection process. While various detection methods are available, electroencephalography (EEG) is considered the gold standard due to its high precision in terms of detecting fatigue. However, deep learning models for EEG-based fatigue detection are limited by their large numbers of parameters and low computational efficiency levels, making it difficult to implement them on mobile devices. METHODS: To overcome this challenge, an attention-based Ghost-LSTM neural network (AGL-Net) is proposed for EEG-based fatigue detection in this paper. AGL-Net utilizes an attention mechanism to focus on relevant features and incorporates Ghost bottlenecks to efficiently extract spatial EEG fatigue information. Temporal EEG fatigue features are extracted using a long short-term memory (LSTM) network. We establish two types of models: regression and classification models. In the regression model, we use linear regression to obtain regression values. In the classification model, we classify features based on the predicted values obtained from regression. RESULTS: AGL-Net exhibits improved computational efficiency and a more lightweight design than existing deep learning models, as evidenced by its floating-point operations per second (FLOPs) and Params values of 2.67 M and 103,530, respectively. Furthermore, AGL-Net achieves an average accuracy of approximately 87.3% and an average root mean square error (RMSE) of approximately 0.0864 with the Shanghai Jiao Tong University (SJTU) Emotion EEG Dataset (SEED)-VIG fatigued driving dataset, indicating its advanced performance capabilities. CONCLUSIONS: The experiments conducted with the SEED-VIG dataset demonstrate the feasibility and advanced performance of the proposed fatigue detection method. The effectiveness of each AGL-Net module is verified through thorough ablation experiments. Additionally, the implementation of the Ghost bottleneck module greatly enhances the computational efficiency of the model. Overall, the proposed method has higher accuracy and computational efficiency than prior fatigue detection methods, demonstrating its considerable practical application value.


Asunto(s)
Emociones , Redes Neurales de la Computación , Humanos , China , Electroencefalografía/métodos , Modelos Lineales
3.
Am J Clin Oncol ; 43(7): 484-490, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32251122

RESUMEN

OBJECTIVES: SLC-0111 is an ureido-substituted benzenesulfonamide small molecule inhibitor of carbonic anhydrase IX. The objectives of this first-in-human Phase 1 study were to determine the safety and tolerability of SLC-0111 in patients with advanced solid tumors and to establish the recommended Phase 2 dose for future clinical investigations. MATERIALS AND METHODS: Using a 3+3 design, dose escalation started at 500 mg oral daily dosing of SLC-0111 in cohort 1 and increased to 1000 and 2000 mg in cohorts 2 and 3. Drug-related adverse events (AEs) were monitored to determine safety and tolerability. Pharmacokinetic analyses assessed plasma concentrations of single and repeated doses of SLC-0111. RECIST 1.1 criteria were used to assess disease progression. RESULTS: No dose-limiting toxicities were reported and patients dosed at ≤1000 mg exhibited fewer drug-related AEs ≥ grade 3 and fewer AEs such as nausea and vomiting, compared with the 2000-mg cohort. Forty-one percent of patients experienced dose interruptions or discontinuation and the majority (71%) of these occurred in the 2000-mg cohort. Mean Cmax and AUC(0-24) values for single doses were similar at the 1000-mg and 2000-mg dose levels. Mean Tmax and T1/2 values of SLC-0111 were similar after single and repeated dosing. Power-law analysis of Cmax and AUC0-24 showed that exposure to SLC-0111 was generally dose proportional. No objective responses were observed, but stable disease >24 weeks was observed in 2 patients. CONCLUSIONS: SLC-0111 was safe in patients with previously treated, advanced solid tumors. The safety and pharmacokinetic data support 1000 mg/d as the recommended phase 2 dose for SLC-0111.


Asunto(s)
Antineoplásicos/uso terapéutico , Anhidrasa Carbónica IX/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Compuestos de Fenilurea/uso terapéutico , Sulfonamidas/uso terapéutico , Adulto , Anciano , Antígenos de Neoplasias , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad
4.
Clin Cancer Res ; 12(12): 3716-22, 2006 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-16778098

RESUMEN

PURPOSE: The collagen triple helix repeat containing 1 (CTHRC1) is a promigratory protein first found to be expressed during rat tissue repair process. Recent preliminary results revealed CTHRC(1) mRNA in melanoma and breast cancer. However, the full significance of CTHRC1 to human carcinogenesis remains unclear. This study is to further characterize the clinical and functional relevance of CTHRC1 in melanoma and other human solid cancers. EXPERIMENTAL DESIGN: First, semiquantitative immunohistochemistry analysis was done on 304 clinically annotated, paraffin-embedded biopsies representing different stages of melanoma progression. Then, short interfering RNA was used to inhibit expression of CTHRC1 protein for migration analysis on cultured melanoma cells. Finally, the CTHRC1 expression was surveyed in 310 samples representing 19 types of human solid cancers. RESULTS: In benign nevi and noninvasive melanoma biopsies, there was little CTHRC1 protein expression. In contrast, in invasive primary melanomas, there was a significant increase of CTHRC1 protein (P < 0.01, chi(2) test). There was a further increase of CTHRC1 protein in metastatic melanoma specimens compared with nonmetastatic lesions (P < 0.01, chi(2) test). In addition, inhibition of CTHRC1 expression resulted in decreased cell migration in vitro. Finally, transcription survey in 19 types of human solid cancers revealed aberrant CTHRC1 expression in 16 cancer types, especially cancers of the gastrointestinal tract, lung, breast, thyroid, ovarian, cervix, liver, and the pancreas. CONCLUSIONS: Aberrant expression of CTHRC1 is widely present in human solid cancers and seems to be associated with cancer tissue invasion and metastasis. It potentially plays important functional roles in cancer progression, perhaps by increasing cancer cell migration.


Asunto(s)
Proteínas de la Matriz Extracelular/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cartilla de ADN , Humanos , Inmunohistoquímica , Invasividad Neoplásica , Metástasis de la Neoplasia , Neoplasias/patología , Reacción en Cadena de la Polimerasa , Interferencia de ARN , Conejos , Secuencias Repetitivas de Aminoácido
5.
Cancer Res ; 65(16): 7338-47, 2005 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16103085

RESUMEN

Internal tandem duplication (ITD) mutations in the FLT3 tyrosine kinase have been detected in approximately 20% of acute myeloid leukemia (AML) patients. Patients harboring FLT3/ITD mutations have a relatively poor prognosis. FLT3/ITD results in constitutive autophosphorylation of the receptor and factor-independent survival. Previous studies have shown that FLT3/ITD activates the signal transducers and activators of transcription 5 (STAT5), p42/p44 mitogen-activated protein kinase [MAPK; extracellular signal-regulated kinase (ERK) 1/2], and phosphatidylinositol 3-kinase/Akt pathways. We herein provide biochemical and biological evidence that ribosomal S6 kinase 1 (RSK1) and protein kinase A (PKA) are the two principal kinases that mediate the antiapoptotic function of FLT3/ITD via phosphorylation of BAD at Ser112. Inhibiting both MAPK kinase (MEK)/ERK and PKA pathways by a combination of U0126 (10 micromol/L) and H-89 (5 micromol/L) reduced most of BAD phosphorylation at Ser112 and induced apoptosis to a level comparable with that induced by FLT3 inhibitor AG1296 (5 micromol/L) in BaF3/FLT3/ITD cells. RNA interference of RSK1 or PKA catalytic subunit reduced BAD phosphorylation and induced apoptosis. The MEK inhibitor U0126 and/or the PKA inhibitor H-89 greatly enhanced the efficacy of the FLT3 inhibitor AG1296, suggesting that combining FLT3/ITD downstream pathway inhibition with FLT3 inhibitors may be a viable therapeutic strategy for AML caused by a FLT3/ITD mutation.


Asunto(s)
Proteínas Portadoras/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Interleucina-3/deficiencia , Mutación , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Quinasas S6 Ribosómicas 90-kDa/metabolismo , Secuencia de Aminoácidos , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Butadienos/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Sinergismo Farmacológico , Activación Enzimática , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/enzimología , Interleucina-3/metabolismo , Isoquinolinas/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Datos de Secuencia Molecular , Nitrilos/farmacología , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Interferencia de ARN , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/metabolismo , Proteínas Quinasas S6 Ribosómicas 90-kDa/antagonistas & inhibidores , Proteínas Quinasas S6 Ribosómicas 90-kDa/genética , Serina/metabolismo , Sulfonamidas/farmacología , Secuencias Repetidas en Tándem/genética , Tirfostinos/farmacología , Proteína Letal Asociada a bcl , Proteína bcl-X , Tirosina Quinasa 3 Similar a fms
6.
Oncotarget ; 8(12): 18712-18725, 2017 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-27213583

RESUMEN

Serpin Peptidase Inhibitor, clade A member 3 (SERPINA3) was found to be abnormally overexpressed in a subset of melanoma tissue biopsies. High SERPINA3 expression was also associated with poor patient survival. In this study, we set out to test SERPINA3 protein's prognostic potential with a larger-sized and independent patient cohort, and to explore SERPINA3's function in melanoma cells. Tissue microarray-based immunohistochemistry analysis showed a significant increase in SERPINA3 expression in invasive and metastatic melanomas compared to normal nevi and melanoma-in-situ (P < 0.001, Chi-square test). In melanoma patients, high SERPINA3 expression was strongly associated with worse overall and disease specific survival at 5 years. Multivariate Cox regression analysis showed that SERPINA3 expression is an independent prognostic factor to predict melanoma patient clinical outcome. When SERPINA3 expression was selectively silenced using small interfering RNA molecules (siRNA) in cultured melanoma cell lines, cell migration and matrix invasion was significantly decreased, but no change in cell proliferation was observed.This study confirms the prognostic potential of SERPINA3 expression in human cutaneous melanoma and reveals the pro-migration and pro-invasion functions of this protein on melanoma cells.


Asunto(s)
Biomarcadores de Tumor/análisis , Movimiento Celular , Melanoma/patología , Serpinas/biosíntesis , Neoplasias Cutáneas/patología , Adulto , Anciano , Movimiento Celular/fisiología , Técnicas de Silenciamiento del Gen , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Pronóstico , Modelos de Riesgos Proporcionales , Análisis de Matrices Tisulares , Regulación hacia Arriba , Melanoma Cutáneo Maligno
7.
Oncotarget ; 8(62): 105081-105092, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29285235

RESUMEN

EYA1 is a DNA repair enzyme that is induced after DNA damage and is upregulated in melanoma. However, its role in pathogenesis and therapeutic targeting of melanoma is unknown. Our objectives are (1) to study the relationship between EYA1 expression levels and melanoma patients' clinical pathologic parameters including survival; (2) to investigate its impact on cultured melanoma cells in vitro; and (3) to evaluate EYA1 inhibitors' potential as a treatment of melanoma. Melanoma tissue microarrays were used to assess EYA1 protein expression in 326 melanoma tissues, and to correlate the expression with patients' clinical pathological parameters. In addition, retroviral ShRNA vectors were used to silence expression of EYA1 in A375 melanoma cells, and the resultant cells examined for changes in growth, DNA synthesis, and tumor formation in vitro. Lastly, melanoma cells were treated with benzbromarone with or without the BRAF inhibitor vemurafenib. Our results showed that EYA1 protein is low in benign nevi, but is significantly up-regulated in melanoma in situ, and remains high in invasive and metastatic melanoma. In addition, silencing of EYA1 gene expression resulted in decreased proliferation and colony formation. These were associated with decreased cyclin D1 and increased phosphorylated histone protein γH2AX. Finally, treatment with benzbromarone, a specific inhibitor of EYA1, caused significant inhibition of melanoma cell proliferation, and increased sensitivity to the BRAF inhibitor vemurafenib. In conclusion, EYA1 gene is a pathogenic driver in melanoma pathogenesis. Targeting EYA1 may be a valuable strategy for treatment of melanoma.

8.
Oncotarget ; 8(31): 50594-50607, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28881586

RESUMEN

Gene fusion is one of the hallmarks of cancer. Recent advances in RNA-seq of cancer transcriptomes have facilitated the discovery of fusion transcripts. In this study, we report identification of a surprisingly large number of fusion transcripts, including six KANSARL (KANSL1-ARL17A) transcripts that resulted from the fusion between the KANSL1 and ARL17A genes using a RNA splicingcode model. Five of these six KANSARL fusion transcripts are novel. By systematic analysis of RNA-seq data of glioblastoma, prostate cancer, lung cancer, breast cancer, and lymphoma from different regions of the World, we have found that KANSARL fusion transcripts were rarely detected in the tumors of individuals from Asia or Africa. In contrast, they exist in 30 - 52% of the tumors from North Americans cancer patients. Analysis of CEPH/Utah Pedigree 1463 has revealed that KANSARL is a familially-inherited fusion gene. Further analysis of RNA-seq datasets of the 1000 Genome Project has indicated that KANSARL fusion gene is specific to 28.9% of the population of European ancestry origin. In summary, we demonstrated that KANSARL is the first cancer predisposition fusion gene associated with genetic backgrounds of European ancestry origin.

9.
Biochim Biophys Acta ; 1591(1-3): 119-128, 2002 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-12183062

RESUMEN

The tight coupling between cell cycle progression and morphogenetic development in the unicellular ciliates presents a unique model system for examination of the roles of Cdks in developmental processes. We here describe the isolation and characterization of the first cyclin-dependent kinase (Cdk) homologue, TtCdk1, from Tetrahymena thermophila. TtCdk1 corresponds to the larger of the two polypeptides recognized by anti-PSTAIRE antibody in a whole cell lysate, which differ from each other in their affinity for yeast p13(suc1) protein. In contrast to the constant protein expression levels of typical eukaryotic Cdks, the TtCdk1 protein level fluctuates periodically over the vegetative cell cycle, reaching a maximum at the end of the cell cycle, correlating with its histone H1 kinase activity. Its association with the membrane-skeletal domains that surround mature, but not nascent, basal bodies in the cell cortex suggests that TtCdk1 plays a role in the regulation of cortical morphogenesis in T. thermophila. A partial TtCDK1 knockout cell line constructed through somatic biolistic transformation resulted in a reduction of the regularity of the rows of basal bodies plus an additional effect on chromatin condensation in both macro- and micronuclei. Unlike the situations in higher eukaryotic cells, no apparent effect on basal body duplication was found upon disruption of the TtCDK1 gene.


Asunto(s)
Proteína Quinasa CDC2/metabolismo , Tetrahymena thermophila/enzimología , Secuencia de Aminoácidos , Animales , Proteína Quinasa CDC2/genética , División Celular/fisiología , Quinasas Ciclina-Dependientes/genética , Quinasas Ciclina-Dependientes/metabolismo , Marcación de Gen , Micronúcleo Germinal , Datos de Secuencia Molecular , Proteínas Quinasas/metabolismo , Estructura Terciaria de Proteína , Homología de Secuencia de Aminoácido , Tetrahymena thermophila/genética
10.
J Invest Dermatol ; 124(5): 1044-52, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15854047

RESUMEN

Melanoma is one of the most aggressive cancers affecting humans. Although early melanomas are curable with surgical excision, metastatic melanomas are associated with high mortality. The mechanism of melanoma development, progression, and metastasis is largely unknown. In order to uncover genes unique to melanoma cells, we used high-density DNA microarrays to examine the gene expression profiles of metastatic melanoma nodules using benign nevi as controls. Over 190 genes were significantly overexpressed in metastatic melanomas compared with normal nevi by at least 2-fold. One of the most abundantly expressed genes in metastatic melanoma nodules is osteopontin (OPN). Immunohistochemistry staining on tissue microarrays and individual skin biopsies representing different stages of melanoma progression revealed that OPN expression is first acquired at the step of melanoma tissue invasion. In addition, blocking of OPN expression by RNA interference reduced melanoma cell numbers in vitro. Our observations suggest that OPN may be acquired early in melanoma development and progression, and may enhance tumor cell growth in invasive melanoma.


Asunto(s)
Melanoma/patología , Sialoglicoproteínas/genética , Adulto , Anciano , Línea Celular Tumoral , Proliferación Celular , Femenino , Humanos , Inmunohistoquímica , Masculino , Melanoma/secundario , Persona de Mediana Edad , Invasividad Neoplásica , Análisis de Secuencia por Matrices de Oligonucleótidos , Osteopontina , ARN Mensajero/análisis , ARN Interferente Pequeño/farmacología , Sialoglicoproteínas/análisis
11.
J Invest Dermatol ; 120(3): 400-6, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12603852

RESUMEN

Alopecia areata is an autoimmune disease targeted at hair follicles with infiltrated T lymphocytes probably playing an important role in the pathogenesis. It was reported in 1985 that mechlorethamine was effective on alopecia areata patients. This has never been confirmed since. The aims of the study were to investigate the effects of mechlorethamine on balding C3H/HeJ mice affected with an alopecia-areata-like disease and to study the underlying mechanisms. Mice were treated on half of the dorsal skin with mechlorethamine and the contralateral side was treated with the vehicle ointment. After 10 wk of mechlorethamine therapy, a full pelage of hair covered the treated side in all the mice and was maintained during the study, whereas the vehicle-treated sides showed either no change or continued hair loss. Immunohistochemistry revealed that infiltrated CD4+ and CD8+ lymphocytes were eliminated from the treated side. In vitro cell viability assay showed that lymphocytes were much more sensitive to the cytotoxic effects of mechlorethamine than skin and hair follicular cells. RNase protection assay and real-time reverse transcription polymerase chain reaction showed that tumor necrosis factor alpha/beta, interleukin-12, and interferon-gamma were inhibited by mechlorethamine upon successful treatment. Our findings support that mechlorethamine restores follicular activity by selectively targeting infiltrated lymphocytes in vivo in alopecia-areata-affected mice.


Asunto(s)
Alquilantes/administración & dosificación , Alopecia Areata/tratamiento farmacológico , Alopecia Areata/fisiopatología , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/fisiopatología , Folículo Piloso/fisiopatología , Linfocitos/efectos de los fármacos , Mecloretamina/administración & dosificación , Animales , Movimiento Celular , Folículo Piloso/efectos de los fármacos , Interferón gamma/antagonistas & inhibidores , Interleucina-12/antagonistas & inhibidores , Linfocitos/fisiología , Linfotoxina-alfa/antagonistas & inhibidores , Ratones , Ratones Endogámicos C3H , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
12.
J Cutan Med Surg ; 15(2): 103-10, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21477558

RESUMEN

BACKGROUND: The extracellular protein collagen triple helix repeat containing 1 (CTHRC1) is aberrantly upregulated in melanoma and most human solid cancers. However, its role in cancer remains unknown. OBJECTIVE: In this study, we investigated the functional impact of CTHRC1 on melanoma cells in vitro. METHODS: Stable clones of cultured melanoma cells expressing different amounts of CTHRC1 protein were generated and evaluated to characterize their growth, survival, and attachment ability as well as their sensitivity to chemotherapy. RESULTS: In cultured MMAN and MMRU melanoma cells, increased expression of CTHRC1 protein resulted in morphologic cell changes, enhanced cell adhesion to culture surfaces, increased cell proliferation, and decreased apoptosis. Furthermore, decreased CTHRC1 expression through antisense inhibition enhanced temozolomide sensitivity. CONCLUSION: CTHRC1 expression influences cellular processes, including cell adhesion and survival. Additionally, CTHRC1 inhibition may represent a potential method for decreasing melanoma resistance to conventional chemotherapy.


Asunto(s)
Adhesión Celular , Supervivencia Celular , Proteínas de la Matriz Extracelular/metabolismo , Melanoma/metabolismo , Melanoma/patología , Antineoplásicos Alquilantes/farmacología , Supervivencia Celular/efectos de los fármacos , Dacarbazina/análogos & derivados , Dacarbazina/farmacología , Matriz Extracelular , Proteínas de la Matriz Extracelular/genética , Expresión Génica , Humanos , Melanoma/genética , Temozolomida , Células Tumorales Cultivadas
14.
J Cutan Med Surg ; 12(2): 64-70, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18346402

RESUMEN

BACKGROUND: Endothelin-3 (ET-3) is an essential paracrine factor for the proliferation, migration, and survival of embryonic melanocytes during fetal development. Its expression is tightly regulated, being completely turned off in adult skin. OBJECTIVE: In this study, results are presented that demonstrate abnormal expression of ET-3 by metastatic melanoma cells in both tissue biopsies and cell culture. Further, in vitro experiments showed that metastatic melanoma cells have the capacity to respond to ET-3 stimulation by increasing survival. CONCLUSION: Therefore, an abnormal autocrine stimulation pathway involving ET-3 is present in metastatic melanoma cells. Blocking this signal transduction pathway may prove useful for the treatment of metastatic melanoma.


Asunto(s)
Endotelina-3/biosíntesis , Regulación Neoplásica de la Expresión Génica/fisiología , Melanoma/metabolismo , Transducción de Señal/fisiología , Neoplasias Cutáneas/metabolismo , Western Blotting , Supervivencia Celular/fisiología , Humanos , Inmunohistoquímica , Técnicas In Vitro , Melanocitos , Melanoma/secundario , Nevo/metabolismo , ARN Mensajero/metabolismo , Neoplasias Cutáneas/secundario , Células Tumorales Cultivadas
15.
Bioorg Med Chem ; 15(13): 4601-8, 2007 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-17467996

RESUMEN

An efficient synthesis and the cytotoxic activity of a series of substituted 6-amino-4H-[1,2]dithiolo[4,3-b]pyrrol-5-ones 1a-q is described. The synthesis was accomplished in an expedient manner (seven-steps) from commercially available starting materials. Several of the derivatives tested demonstrated significant in vitro cytotoxic activity against the human cancer cell lines H460 (7nM) and LCC6 (> or =28nM). Following SAR and pharmacokinetic studies a derivative was further evaluated for its in vivo anti-tumor activity against a highly angiogenic human melanoma xenograft where it demonstrated significant efficacy as a mono-therapy and in combination with Taxol and Cisplatin.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Compuestos Heterocíclicos con 2 Anillos/farmacología , Pirroles/farmacología , Animales , Antineoplásicos/farmacocinética , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Compuestos Heterocíclicos con 2 Anillos/farmacocinética , Masculino , Ratones , Trasplante de Neoplasias , Neoplasias Experimentales/tratamiento farmacológico , Pirroles/farmacocinética , Relación Estructura-Actividad
16.
J Cutan Med Surg ; 10(6): 269-76, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17241596

RESUMEN

BACKGROUND: Endothelins are paracrine peptides with growth-promoting and vasoactive functions for a variety of cell types. Elevated activation of the endothelin signaling pathway induces cell proliferation and/or survival and is implicated in a variety of malignancies. Increased endothelin 1 was described in solar lentigines in previous reports, raising the possibility that the endothelin pathway may be of significance in keratinocyte proliferation-related disorders. However, detailed investigation on endothelins in skin malignancies is lacking. OBJECTIVES: This study aims to survey the expression of endothelins and their receptors in keratinocyte-derived benign and malignant tumors of the skin and to test the effects of endothelin inhibitors on the growth and survival of cultured keratinocytes. METHODS: Quantitative polymerase chain reaction was used to measure the level of gene transcription of three endothelins (ET-1, -2, and -3) and two endothelin receptors (ETRA and ETRB). The genes with significant messenger ribonucleic acid (mRNA) expression abnormalities were confirmed with immunohistochemical analysis to examine expression differences at the protein levels. To analyze the effect of endothelin inhibitors on the keratinocyte growth and survival, keratinocytes were cultured in the presence of various concentrations of endothelin inhibitors and subjected to tetrazolium bromide assay to quantify the cell numbers over time. RESULTS: ET-1 mRNA was found to be significantly up-regulated in seborrheic keratosis and basal cell carcinoma. However, no significant expression increase was found in actinic keratosis, Bowen's disease, or squamous cell carcinoma. Immunohistochemical analysis of ET-1 peptide confirmed increased expression. In cultured keratinocytes, peptide inhibitors of the endothelin pathway resulted in a marked reduction in cell survival. CONCLUSION: The endothelin signaling pathway, especially ET-1, is activated in basal keratinocyte neoplasms of the skin, such as basal cell carcinoma and seborrheic keratosis. Blockade of this pathway can reduce cell survival in vitro. Therefore, endothelin inhibitors potentially offer a novel method for the treatment of some keratinocyte-derived skin tumors.


Asunto(s)
Carcinoma Basocelular/metabolismo , Carcinoma de Células Escamosas/metabolismo , Endotelinas/metabolismo , Receptores de Endotelina/metabolismo , Neoplasias Cutáneas/metabolismo , Biomarcadores de Tumor/genética , Enfermedad de Bowen/metabolismo , Carcinoma Basocelular/genética , Carcinoma Basocelular/patología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Endotelina-1/genética , Endotelina-2/genética , Endotelinas/genética , Humanos , Inmunohistoquímica , Queratosis/metabolismo , Queratosis Seborreica/metabolismo , Reacción en Cadena de la Polimerasa , ARN Mensajero , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/metabolismo , Receptores de Endotelina/genética , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Transcripción Genética
18.
J Investig Dermatol Symp Proc ; 8(2): 212-6, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14582676

RESUMEN

Alopecia areata is regarded as a tissue-restricted autoimmune disease of hair follicles in which follicular activity is arrested because of the continued activity of lymphocytic infiltrates. Actual loss of hair follicles does not occur, even in hairless lesions. A variety of immunomodulating therapies, including contact sensitizers and immunomodulators, are part of the usual armamentarium for this disorder. None of these treatments have been consistent in their efficacy, and many have untoward side effects. Nevertheless, their uses in valid animal models provide a tool to dissect out molecular mechanisms of therapeutic effects. For several decades, both mechlorethamine (for the treatment of cutaneous T cell lymphoma) and anthralin (for the treatment of psoriasis) have been used successfully. When these therapies were tested in rat and mouse alopecia areata models, we found anthralin and mechlorethamine to be the most effective topical modalities, respectively. The underlying cellular mechanisms may act through targeting infiltrative lymphocytes, and the molecular mechanisms may involve specific cytokine expression changes. These visible, accessible, and unilaterally treated animal model systems are ideal for studying novel alopecia areata therapies, particularly in terms of their in vivo molecular mechanisms of action.


Asunto(s)
Alopecia Areata/tratamiento farmacológico , Antralina/uso terapéutico , Mecloretamina/uso terapéutico , Animales , Modelos Animales de Enfermedad , Roedores
19.
J Am Acad Dermatol ; 49(2): 291-4, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12894080

RESUMEN

Topical nitrogen mustard is an alkylating agent. Its efficacy in treating alopecia areata was reported in an uncontrolled study. We present a preliminary, half-head, controlled 16-week study showing that topical nitrogen mustard was of benefit in 1 of 6 patients treated with 50% to 100% scalp involvement. Another 4 patients did not complete the trial.


Asunto(s)
Alquilantes/uso terapéutico , Alopecia Areata/tratamiento farmacológico , Mecloretamina/uso terapéutico , Administración Tópica , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
J Am Acad Dermatol ; 49(2): 229-33, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12894070

RESUMEN

BACKGROUND: It is generally believed that dihydrotestosterone is one of the pivotal mediators of hair loss in androgenetic alopecia (AGA). Finasteride, which blocks the conversion of testosterone to dihydrotestosterone, has now become an integral part of the current treatment approaches for male AGA. Several lines of evidence support the notion that dermal papilla (DP) cells represent the androgen target within the hair follicle. The specific molecular regulators modulated by androgens within hair follicles in the balding scalp are unknown. OBJECTIVE: The purpose of this study was to identify and quantify changes in expression of specific molecular hair growth regulators in DP of men with AGA treated with finasteride and correlate these findings to clinical efficacy. METHODS: Biopsy specimens were collected from 9 male patients from both the balding area and nonbalding occipital area before and after 4 months of finasteride therapy. DP were microdissected and total RNA was extracted from an equal number of DP from each biopsy specimen. The expression of various cytokines, including insulin-like growth factor (IGF)-1, was determined by reverse transcription polymerase chain reaction. The signals were detected by autoradiography. All 9 patients were given finasteride for 1 year and evaluated for efficacy at month 12. Efficacy was graded on a 7-point scale on the basis of comparison with initial baseline photography. RESULTS: IGF-1 was up-regulated by finasteride treatment in 4 of 9 patients. Among the patients with increased IGF-1 expression, 3 of them showed moderate clinical improvement after 12 months of treatment and another patient remained unchanged. In contrast, 3 patients with decreased IGF-1 expression in the balding scalp showed clinical worsening after 12 months. The other 2 patients without noticeable change in IGF-1 expression showed either slight improvement or no change in their hair condition. CONCLUSION: In a small uncontrolled study of 9 patients with AGA, an increased expression of IGF-1 messenger RNA levels in the DP was associated with patient response to finasteride.


Asunto(s)
Alopecia/tratamiento farmacológico , Inhibidores Enzimáticos/uso terapéutico , Finasterida/uso terapéutico , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Adulto , Alopecia/metabolismo , Alopecia/patología , Inhibidores Enzimáticos/farmacología , Finasterida/farmacología , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Humanos , Factor I del Crecimiento Similar a la Insulina/genética , Masculino , Persona de Mediana Edad , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Regulación hacia Arriba
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