Clonal landscape and clinical outcomes of telomere biology disorders: somatic rescuing and cancer mutations.

Telomere biology disorders (TBD), caused by pathogenic germline variants in telomere-related genes, present with multi-organ disease and a predisposition to cancer. Clonal hematopoiesis (CH) as a marker of cancer development and survival in TBD is poorly understood. Here, we characterized the clonal landscape of a large cohort of 207 TBD patients with a broad range of age and phenotype. CH occurred predominantly in symptomatic patients and in signature genes typically associated with cancers: PPM1D, POT1, TERT promoter (TERTp), U2AF1S34, and/or TP53. Chromosome 1q gain (Chr1q+) was the commonest karyotypic abnormality. Clinically, multiorgan involvement and CH in TERTp, TP53, and splicing factor genes associated with poorer overall survival. Chr1q+, and splicing factor or TP53 mutations significantly increased the risk of hematologic malignancies, regardless of the clonal burden. Chr1q+ and U2AF1S34 mutated clones were pre-malignant events associated with the secondary acquisition of mutations in genes related to hematologic malignancies. Like known effects of Chr1q+ and TP53-CH, functional studies demonstrated that U2AF1S34 mutations primarily compensated for aberrant upregulation of TP53 and interferon pathways in telomere-dysfunctional hematopoietic stem cells, highlighting the TP53 pathway as a canonical route of malignancy in TBD. In contrast, somatic POT1/PPM1D/TERTp-CH had distinct trajectories unrelated to cancer development. With implications beyond TBD, our data show that telomere dysfunction is a strong selective pressure for CH. In TBD, CH is a poor prognostic marker associated with worse overall survival. The identification of key regulatory pathways that drive clonal transformation in TBD allows the identification of patients at a higher risk of cancer development.

A strategy for molecular diagnostics of Fanconi anemia in Brazilian patients.

BACKGROUND: Fanconi anemia (FA) is a predominantly autosomal recessive disease with wide genetic heterogeneity resulting from mutations in several DNA repair pathway genes. To date, 21 genetic subtypes have been identified. We aimed to identify the FA genetic subtypes in the Brazilian population and to develop a strategy for molecular diagnosis applicable to routine clinical use. METHODS: We screened 255 patients from Hospital de Clínicas, Universidade Federal do Paraná for 11 common FA gene mutations. Further analysis by multiplex ligation-dependent probe amplification (MLPA) for FANCA and Sanger sequencing of all coding exons of FANCA, -C, and -G was performed in cases who harbored a single gene mutation. RESULTS: We identified biallelic mutations in 128/255 patients (50.2%): 89, 11, and 28 carried FANCA,FANCC, and FANCG mutations, respectively. Of these, 71 harbored homozygous mutations, whereas 57 had compound heterozygous mutations. In 4/57 heterozygous patients, both mutations were identified by the initial screening, in 51/57 additional analyses was required for classification, and in 2/57 the second mutation remained unidentified. We found 52 different mutations of which 22 were novel. CONCLUSION: The proposed method allowed genetic subtyping of 126/255 (49.4%) patients at a significantly reduced time and cost, which makes molecular diagnosis of FA Brazilian patients feasible.

Long-term follow-up and factors influencing outcomes after related HLA-identical cord blood transplantation for patients with malignancies: an analysis on behalf of Eurocord-EBMT.

We analyzed risk factors influencing outcomes after related (R) human leukocyte antigen-identical cord blood transplantation (CBT) for 147 patients with malignancies reported to Eurocord-European Group for Blood and Marrow Transplantation. CBT has been performed since 1990; median follow-up was 6.7 years. Median patient age was 5 years. Acute leukemia was the most frequent diagnosis (74%). At CBT, 40 patients had early, 70 intermediate, and 37 advanced disease. CB grafts contained a median of 4.1 × 10(7)/kg total nucleated cells (TNCs) after thawing. The cumulative incidence (CI) of neutrophil recovery was 90% at day +60. CIs of acute and chronic graft-versus-host disease (GVHD) were 12% and 10% at 2 years, respectively. At 5 years, CIs of nonrelapse mortality and relapse were 9% and 47%, respectively; the probability of disease-free survival (DFS) and overall survival were 44% and 55%, respectively. Among other factors, higher TNCs infused was associated with rapid neutrophil recovery and improved DFS. The use of methotrexate as GVHD prophylaxis decreased the CI of engraftment. Patients without advanced disease had improved DFS. These results support banking and use of CB units for RCBT. Cell dose, GVHD prophylaxis not including methotrexate, and disease status are important factors for outcomes after RCBT.

Análise retrospectiva dos pacientes infectados por RSV na unidade de transplante de medula óssea / RSV infection after allogeneic hematopoietic stem cell transplanttrans planted in a single institutionation (HSCT): analysis of 59 patients

O vírus sincicial respiratório (RSV) é considerado uma causa importante de morbi-mortalidade em pacientes submetidos ao transplante de células-tronco hematopoéticas (TCTH). Mesmo com o uso da ribavirina inalatória (RI), as taxas de mortalidade são de 30 por cento a 40 por cento . O objetivo deste trabalho foi analisar o perfil dos pacientes infectados pelo RSV e a eficácia do tratamento com RI. Realizou-se uma análise retrospectiva de 59 pacientes submetidos ao TCTH com infecção confirmada pelo RSV (métodos de IFI ou PCR) entre 02/1991 e 02/2008. A RI foi administrada por 12 horas, na dose de 5 g diluída 200 ml de água destilada, por cinco dias. Quinze pacientes apresentaram infecções (TRI) do trato respiratório inferior e 44 pacientes apresentaram infecções (TRS) de vias aéreas superiores. No grupo tratado (n=50), quarenta apresentaram infecções no TRS versus dez TRI; no grupo não tratado, quatro TRS versus cinco TRI. Foram constatados vinte óbitos (33,8 por cento), sendo que 13 desses pacientes (65 por cento dos óbitos) tiveram suas mortes relacionadas ao RSV. Dentre estes, nove pacientes foram a óbito antes da instituição da RI como terapia padrão. A sobrevida global (SG) de todos os pacientes foi de 8,3 meses, sendo 66 por cento para o grupo que utilizou RI versus 11,1 por cento no grupo não tratado(p=0,001). No entanto, a SG foi inferior nos pacientes que apresentaram infecções no TRI (37,5 por cento) quando comparadas às infecções do TRS (65,1 por cento), p=0,007. No modelo de regressão de Cox, a única variável independente encontrada foi o tratamento com RI (p=0,001).

Respiratory syncytial virus (RSV) causes significant mortality in patients submitted to SCT. Despite the use of ribavirin aerosols (RA), mortality rates are still between 30 and 40 percent in many centers. The objective of this study was to analyze the clinical course and outcome of 59 patients who developed RSV infections after SCT in a single institution. In this retrospective analysis, the diagnosis of RSV infection was confirmed in 59 patients submitted to HSCT. RA was administrated during 12 hours at a dose of 5g diluted in 200 mL of distillated water, for 5 days. Fifteen patients presented with upper respiratory tract (URT) infection and 44 patients presented with lower respiratory tract (LRT) infection. In the group of patients who received RA (n=50), 40 had URT infections and 10 had LRT infections. In patients who did not receive RA, 3 had URT infections and 6 had LRT infections. Twenty patients died (33.8 percent) with the main cause of death of 13 patients being RSV infection (all these patients required mechanical ventilation). Nine patients died before RA therapy became standard treatment for RSV (before 1992). The overall survival of patients treated with RA was 66 percent. However, the overall survival was lower in patients who had LRT infections (37.5 percent) compared with those who had URT infections (67.5 percent - p=0.007). In the multivariate analysis, only the use of RA affected overall survival (p=0.001).

Carcinoma de células escamosas em língua pós-transplante de medula óssea por Anemia de Fanconi / Squamous cell carcinoma of the tongue due to Fanconi's Anemia after bone marrow transplantation

Anemia Fanconi (AF) é uma síndrome autossômica recessiva, caracterizada por pancitopenia progressiva com hipoplasia de MO, em associação com várias anormalidades constitucionais, tendo como único recurso terapêutico com possibilidade potencial de cura o transplante de medula óssea, e sendo tais pacientes propensos ao desenvolvimento de malignidades hematológicas e carcinoma de células escamosas (CEC) em diversos locais: reto, vagina, cérvice, esôfago, cavidade bucal, faringe ou pele, mas especialmente em cabeça e pescoço. Relatamos aqui três casos de pacientes portadores de AF, que após TMO desenvolveram CEC em língua. Além disso, mencionamos fatores de risco relatados para tal evento, como diagnóstico de AF, condicionamento pré-transplante (quimioterápicos e irradiação), terapia com drogas imunossupressoras para tratamento de doença enxerto contra hospedeiro (DECH) aguda ou crônica, sexo e idade avançada. Além do que, discorremos sobre a existência de três mecanismos postulados que predispõem indivíduos com AF ao desenvolvimento de neoplasia: (1) defeito na reparação do DNA; (2) defeito na detoxificação de radicais de oxigênio; e (3) imunodeficiência.

Fanconi’s Anemia, first described in 1927, is a rareautonomic recessive disease characterized byprogressive pancytopenia, congenital malformations,spontaneous or chemically induced chromosomebreakage and increased incidence of leukemia andother cancers. The onset of bone marrow hypoplasiaand its hematological manifestations is usually in the3 - 7 year age range. Additionally, we discussed the existence ofthree postulated mechanisms that make individualswith Fanconi’s anemia susceptible to the developmentof neoplasias: (1) deficiency in the DNA repair system,(2) deficiency in oxygen radical detoxification; and(3) immunodeficiency.