RESUMEN
BACKGROUND: Rhabdomyosarcoma (RMS) is the most frequent sporadic soft tissue sarcoma of childhood and adolescence. The overall 5-year survival rate for patients with RMS is 70% with the use of surgery, radiation, and chemotherapy. Novel therapeutic approaches are necessary to improve on these outcomes particularly among the more aggressive alveolar RMS (ARMS) and late stages of disease, where 5-year survival is less than 20%. Retinoids have been successfully used in the treatment of acute promyelocytic leukemia (APML) and neuroblastoma. PURPOSE: However, analysis of retinoids as a differentiating agent for RMS has been incomplete. This work examined the ability of retinoic acid (RA) to promote differentiation of RMS cell lines by examining the expression of myogenic proteins in five RMS cell lines in response to All-trans Retinoic Acid (ATRA) or 9-cis retinoic acid (CRA). RESULTS: Analysis of growth curves indicates that both retinoids suppress cell growth of Rh4 and Rh28. RD cells only responded to-CRA whereas Rh30 and Rh18 did not respond. Following treatment with ATRA FACS analysis showed an altered cell cycle with the same pattern as the growth curves. ATRA altered cellular morphology of two cell lines, Rh4 and Rh28, and induced Troponin T expression in these cells suggesting a differentiating effect. CONCLUSIONS: These studies suggest that retinoids are effective inducers of growth arrest and differentiation in some RMS cell lines, and offer a basis for further in vivo testing in mice of ATRA as a potential approach to ARMS treatment.
Asunto(s)
Diferenciación Celular/efectos de los fármacos , Rabdomiosarcoma/tratamiento farmacológico , Tretinoina/farmacología , Proteína p53 Supresora de Tumor/genética , Alitretinoína , Antineoplásicos/farmacología , Western Blotting , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Etanol/farmacología , Citometría de Flujo/métodos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Inmunohistoquímica , Mutación , Rabdomiosarcoma/genética , Rabdomiosarcoma/patología , Sensibilidad y Especificidad , Troponina T/análisis , Células Tumorales CultivadasRESUMEN
The role of genetics in parkinsonism has been confirmed over the last decade with the identification of genetic variation in seven genes, which are causative in familial forms of the disorder. A number of pathogenic mutations have been identified in the latest gene LRRK2, with a Gly2019Ser amino acid substitution identified in two siblings and one patient with idiopathic Parkinson's disease from Ireland. The clinical features resemble the idiopathic variant with a tremor predominant clinical picture shared by the siblings, slow progression of symptoms, and no observation of cognitive disturbance in all. The family and the sporadic individual were apparently not related and originated from different regions of Ireland, although haplotype analysis does suggest they share a common founder. The influence of the G2019S substitution on protein function and disease phenotype has yet to be fully resolved, but its elucidation will undoubtedly further our understanding of the mechanisms underlying Parkinson's disease.
Asunto(s)
Enfermedad de Parkinson/genética , Enfermedad de Parkinson/fisiopatología , Proteínas Serina-Treonina Quinasas/genética , Adulto , Sustitución de Aminoácidos , Antiparkinsonianos/uso terapéutico , Cognición/fisiología , Progresión de la Enfermedad , Lateralidad Funcional/fisiología , Haplotipos , Humanos , Irlanda , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina , Levodopa/uso terapéutico , Masculino , Persona de Mediana Edad , Mutación/fisiología , Pruebas Neuropsicológicas , Enfermedad de Parkinson/psicologíaRESUMEN
Multiple early-onset tumors, frequently associated with germ line TP53 mutations characterize the Li-Fraumeni familial cancer syndrome (LFS). LFS-like (LFS-L) families have lower rates of germ line TP53 alteration and do not meet the strict definition of LFS. This study examined 7 LFS cell lines and 30 LFS and 36 LFS-L primary leukocyte samples for mutations in the proapoptotic p53-regulated gene BAX. No germ line BAX mutations were found. A known BAX polymorphism was observed, yet there was no correlation between polymorphism frequency and TP53 status in either LFS or LFS-L. In summary, alterations of BAX are not responsible for cancers in TP53 wild-type LFS or LFS-L families.