ABSTRACT
Fanconi anemia (FA) is a chromosome instability syndrome with congenital abnormalities, cancer predisposition and bone marrow failure (BMF). Although hematopoietic stem and progenitor cell (HSPC) transplantation is the recommended therapy, new therapies are needed for FA patients without suitable donors. BMF in FA is caused, at least in part, by a hyperactive growth-suppressive transforming growth factor ß (TGFß) pathway, regulated by the TGFß1, TGFß2, and TGFß3 ligands. Accordingly, the TGFß pathway is an attractive therapeutic target for FA. While inhibition of TGFß1 and TGFß3 promotes blood cell expansion, inhibition of TGFß2 is known to suppress hematopoiesis. Here, we report the effects of AVID200, a potent TGFß1- and TGFß3-specific inhibitor, on FA hematopoiesis. AVID200 promoted the survival of murine FA HSPCs in vitro. AVID200 also promoted in vitro the survival of human HSPCs from patients with FA, with the strongest effect in patients progressing to severe aplastic anemia or myelodysplastic syndrome (MDS). Previous studies have indicated that the toxic upregulation of the nonhomologous end-joining (NHEJ) pathway accounts, at least in part, for the poor growth of FA HSPCs. AVID200 downregulated the expression of NHEJ-related genes and reduced DNA damage in primary FA HSPC in vitro and in in vivo models. Collectively, AVID200 exhibits activity in FA mouse and human preclinical models. AVID200 may therefore provide a therapeutic approach to improving BMF in FA.
Subject(s)
Fanconi Anemia/drug therapy , Hematopoiesis/drug effects , Transforming Growth Factor beta1/antagonists & inhibitors , Transforming Growth Factor beta3/antagonists & inhibitors , Adolescent , Adult , Animals , Cell Survival/drug effects , Cells, Cultured , Child , Child, Preschool , Fanconi Anemia/metabolism , Fanconi Anemia/physiopathology , Female , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/pathology , Humans , Male , Mice , Transforming Growth Factor beta1/metabolism , Transforming Growth Factor beta3/metabolismABSTRACT
INTRODUCCIÓN: La linfohistiocitosis hemofagocitica (HLH) secundario está asociada a enfermedades malignas, genéticas o autoinmunes, pero también a infecciones principalmente EBV hasta en un 70%, sin embargo hay poca información. Esta entidad se caracteriza por un curso variable y recurrente que conlleva a una alta morbimortalidad con complicaciones potencialmente mortales. OBJETIVO: Describir las características clínicas y evolución de los pacientes pediátricos con diagnóstico de HLH secundario a CAEBV. RESULTADOS: Se incluyeron 7 pacientes, edad media al diagnóstico fue 52 meses con predilección al sexo masculino. Todos los pacientes fueron tratados con un régimen quimioterapéutico multiagente, que incluye corticosteroide, etopósido y Ciclosporina. Después del tratamiento 6 pacientes presentaron remisión y uno de ellos reactivación. La media de seguimiento fue 19 meses y la supervivencia libre de enfermedad (SLE) 16 meses. CONCLUSIÓN: Podemos observar que el curso clínico es variable en ocasiones fulminantes y con pobre respuesta al tratamiento. Un diagnóstico temprano, así como detectar los factores pronóstico podría ayudar a adaptar estrategias de tratamiento que cambiaría la evolución clínica.
INTRODUCTION: Secondary hemophagocytic lymphohistiocytosis (HLH) is associated with malignant, genetic or autoimmune diseases but also with infections mainly EBV in up to 70%, however there is little information. This entity is characterized by a variable and recurrent course that leads to high morbidty and mortality with life-threatening complications. OBJECTIVE: To describe the clinical characteristics and evolution of pediatric patients with a diagnosis of HLH secondary to CAEBV. RESULTS: 7 patients were included, mean age at diagnosis was 52 months with a predilection for males. All patients were treated with a multiagent chemotherapeutic regimen, including corticosteroid, etoposide, and cyclosporine. After treatment, 6 patients presented remission and one of them had reactivation. The mean follow-up was 19 months and disease-free survival (DFS) 16 months. CONCLUSION: We can observe that the clinical course is variable, sometimes fulminant and with poor response to treatment. An early diagnosis as well as detecting prognostic factors could help to adapt treatment strategies that would change the clinical course.
Subject(s)
Humans , Male , Female , Child , Epstein-Barr Virus Infections/complications , Lymphohistiocytosis, Hemophagocytic/etiology , Cyclosporine/therapeutic use , Adrenal Cortex Hormones/therapeutic use , Disease-Free Survival , Drug Therapy, Combination , Lymphohistiocytosis, Hemophagocytic/diagnosis , Lymphohistiocytosis, Hemophagocytic/drug therapy , Etoposide/therapeutic use , Hospitals, PediatricABSTRACT
Introducción. El síndrome de Hermansky-Pudlak es un padecimiento genético caracterizado por albinismo y hemorragias, en grado variable, por alteraciones en la estructura de las plaquetas. Puede presentar alteraciones pulmonares, intestinales o renales. En la literatura se han reportado varias alteraciones genéticas relacionadas a este síndrome. Casos clínicos. Se presentan dos casos. El primero se trató de un adolescente de sexo masculino con albinismo mucocutáneo y afección a nivel renal. Los episodios de sangrado iniciaron después de ser sometido a venopunciones y estudios invasivos. Desarrolló, incluso, un hematoma perirrenal. Después de una sepsis de foco abdominal, presentó hemoperitoneo y hemorragia pulmonar, que precipitó su muerte; el diagnóstico se realizó post mórtem. El segundo caso se trató de una paciente de sexo femenino en quien, desde el periodo de lactancia, se identificó el síndrome por el albinismo mucocutáneo, los episodios de sangrado y los datos de fibrosis pulmonar progresiva, lo que ha limitado su capacidad vital. Conclusiones. El diagnóstico del síndrome, así como el abordaje correcto y temprano pueden evitar el desarrollo de complicaciones o limitar su evolución. Aún es materia de debate si las alteraciones genéticas descritas se asocian a la expresión de alguna manifestación clínica particular.
Background. Hermansky-Pudlak syndrome is a genetic disorder characterized by albinism and bleeding of varying degrees due to alteration in the structure of the platelets. The disorder may be accompanied by pulmonary, intestinal or kidney involvement. Identification of several genetic alterations in this syndrome has been reported. Case reports. We present two cases: the first of an adolescent male with mucocutaneous albinism and renal involvement. Bleeding episodes started after being subjected to invasive studies and venipunctures, developing a perinephric hematoma. After severe sepsis, the patient developed hemoperitoneum and pulmonary hemorrhage, which precipitated the patient's death. Diagnosis was made postmortem. In the second case, a female patient was diagnosed during infancy due to albinism and bleeding episodes, with progressive pulmonary fibrosis that to date has limited her vital lung capacity. Conclusions. Early diagnosis of the syndrome as well as the correct approach may prevent the development of complications or limit the evolution. It is still under debate whether the genetic alterations described are associated with the expression of any particular clinical manifestation.
