RESUMO
Utilizing RNA sequence (RNA-Seq) splice junction data from a cohort of 1841 B-cell acute lymphoblastic leukemia (B-ALL) patients we define transcriptionally distinct isoforms of ARID5B, a risk-associated gene identified in genome wide association studies (GWAS), which associate with disease survival. Short (S) and long (L) ARID5B transcripts, which differ in an encoded BAH-like chromatin interaction domain, show remarkable correlation to the isoform splicing pattern. Testing of the ARID5B proximal promoter of the S & L isoforms indicated that both are functionally independent in luciferase reporter assays. Increased short isoform expression is associated with decreased event-free and overall survival. The abundance of short and long transcripts strongly correlates to B-ALL prognostic stratification, where B-ALL subtypes with poor outcomes express a higher proportion of the S-isoform. These data demonstrate that the analysis of independent promoters and alternative splicing events are essential for improved risk stratification and a more complete understanding of disease pathology.
Assuntos
Processamento Alternativo , Estudo de Associação Genômica Ampla , Humanos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Splicing de RNA , Sequência de Bases , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Acute lymphoblastic leukemia expressing the gamma delta T cell receptor (yo T-ALL) is a poorly understood disease. We studied 200 children with yo T-ALL from 13 clinical study groups to understand the clinical and genetic features of this disease. We found age and genetic drivers were significantly associated with outcome. yo T-ALL diagnosed in children under three years of age was extremely high-risk and enriched for genetic alterations that result in both LMO2 activation and STAG2 inactivation. Mechanistically, using patient samples and isogenic cell lines, we show that inactivation of STAG2 profoundly perturbs chromatin organization by altering enhancer-promoter looping, resulting in deregulation of gene expression associated with T-cell differentiation. High throughput drug screening identified a vulnerability in DNA repair pathways arising from STAG2 inactivation, which can be targeted by Poly(ADP-ribose) polymerase (PARP) inhibition. These data provide a diagnostic framework for classification and risk stratification of pediatric yo T-ALL.
RESUMO
ABSTRACT Purpose: To investigate the incidence, risk factors, and visual outcomes of epiretinal membrane development following rhegmatogenous retinal detachment repair. Methods: This was a retrospective study of 309 eyes that underwent initial surgery for primary uncomplicated rhegmatogenous retinal detachment. Examinations were conducted preoperatively and then postoperatively at 1, 3, 6, and 12 months. The study patients were categorized into two groups depending on the presence or absence of the epiretinal membrane. Results: The incidence of postoperative epiretinal membrane was 28.5%; 42.7% of these patients had severe epiretinal membrane development and therefore underwent the epiretinal membrane removal. Logistic regression analyses revealed that giant retinal tears (OR: 2.66; 95% CI: 1.045-6.792, p=0.040) and horseshoe tears (OR: 0.534; 95% CI: 0.295-0.967, p=0.039) were the significant predictors of postoperative epiretinal membrane. Triamcinolone acetonide staining was significantly associated with the prevention of epiretinal membrane (p=0.022). A total of 34 patients showed a better or an equal final best-corrected visual acuity; of which 4 eyes were evaluated at the final follow-up visit and exhibited a reduced best-corrected visual acuity. Conclusion: Our analysis demonstrated that horseshoe tears and giant retinal tears represent the risk factors for the postoperative epiretinal membrane. Triamcinolone acetonide staining had a significant preventive effect on the postoperative epiretinal membrane. Furthermore, a second round of pars plana vitrectomy, including membrane removal, led to a significant improvement in the final best-corrected visual acuity as per the last follow-up examination, albeit the recovery was limited.
RESUMO Objetivos: Investigar a incidência, fatores de risco e desfechos visuais do desenvolvimento da membrana epirretiniana após reparo do descolamento regmatogênico da retina. Métodos: Trata-se de um estudo retrospectivo de 309 olhos submetidos à cirurgia inicial para descolamento regmatogênico da retina primário sem complicações. Os exames foram realizados no pré-operatório aos 1, 3, 6 e 12 meses pós-operatórios. Os pacientes foram divididos em dois grupos, dependendo da presença ou ausência de membrana epirretiniana. Resultados: A incidência de membrana epirretiniana pós-operatória foi de 28,5%; 42,7% desses pacientes apresentaram desenvolvimento grave da membrana epirretiniana e, portanto, foram submetidos à remoção desta membrana. A regressão logística mostrou que as lágrimas retinianas gigantes (RC: 2,66; 95% IC: 1,045 - 6,792, p=0,040) e lágrimas em ferradura (RC: 0,534; 95% IC: 0,295-0,967, p=0,039), foram preditores significativos de membrana epirretiniana pós-operatória. A coloração com acetonida de triancinolona foi significativamente associada à prevenção da membrana epirretiniana (p=0,022). Trinta e quatro pacientes apresentaram acuidade visual melhorada, ou igual, ou acuidade visual final melhor corrigida; 4 olhos foram avaliados na consulta final de acompanhamento e apresentaram redução da acuidade visual melhor corrigida. Conclusão: Nossa análise demonstra que as lágrimas de ferradura e as lágrimas retinianas gigantes representam fatores de risco para a membrana epirretiniana pós-operatória. A coloração com acetonida de triancinolona teve um efeito preventivo significativo na membrana epirretiniana no pós-operatório. Além disso, uma segunda rodada de vitrectomia pars plana, incluindo remoção da membrana, levou a uma melhora significativa da acuidade visual final melhor corrigida na última consulta de acompanhamento, embora a recuperação tenha sido limitada.