Genomic landscape of Down syndrome-associated acute lymphoblastic leukemia.

Trisomy 21, the genetic cause of Down syndrome (DS), is the most common congenital chromosomal anomaly. It is associated with a 20-fold increased risk of acute lymphoblastic leukemia (ALL) during childhood and results in distinctive leukemia biology. To comprehensively define the genomic landscape of DS-ALL, we performed whole-genome sequencing and whole-transcriptome sequencing (RNA-Seq) on 295 cases. Our integrated genomic analyses identified 15 molecular subtypes of DS-ALL, with marked enrichment of CRLF2-r, IGH::IGF2BP1, and C/EBP altered (C/EBPalt) subtypes compared with 2257 non-DS-ALL cases. We observed abnormal activation of the CEBPD, CEBPA, and CEBPE genes in 10.5% of DS-ALL cases via a variety of genomic mechanisms, including chromosomal rearrangements and noncoding mutations leading to enhancer hijacking. A total of 42.3% of C/EBP-activated DS-ALL also have concomitant FLT3 point mutations or insertions/deletions, compared with 4.1% in other subtypes. CEBPD overexpression enhanced the differentiation of mouse hematopoietic progenitor cells into pro-B cells in vitro, particularly in a DS genetic background. Notably, recombination-activating gene-mediated somatic genomic abnormalities were common in DS-ALL, accounting for a median of 27.5% of structural alterations, compared with 7.7% in non-DS-ALL. Unsupervised hierarchical clustering analyses of CRLF2-rearranged DS-ALL identified substantial heterogeneity within this group, with the BCR::ABL1-like subset linked to an inferior event-free survival, even after adjusting for known clinical risk factors. These results provide important insights into the biology of DS-ALL and point to opportunities for targeted therapy and treatment individualization.

Pregnant women's perspectives about maternal immunization in Latin America.

BACKGROUND: Maternal immunization rates and vaccine uptake in Latin America vary from country to country. This variability stems from factors related to pregnant women, vaccine recommendations from healthcare providers and the health system. The aim of this paper is to describe women's knowledge and attitudes to maternal immunziation, and barriers to access and vaccination related decision-making processes in Latin American countries. METHODS: We conducted focus group discussions (FGD) with pregnant women in five middle-income countries: Argentina, Brazil, Honduras, Mexico and Peru, between July 2016 and July 2018. The FGDs were conducted by trained qualitative researchers in diverse clinics located in the capital cities of these countries. RESULTS: A total of 162 pregnant women participated in the FGDs. In general, participants were aware of the recommendation to receive vaccines during pregnancy but lacked knowledge regarding the diseases prevented by these vaccines. Pregnant women expressed a desire for clearer and more detailed communication on maternal vaccines by their healthcare professionals instead of relying on other sources of information such as the internet. Overall, participants had positive attitudes towards maternal immunization and were open to receiving vaccines in pregnancy based on general trust they have in recommendations made by their healthcare providers. The main obstacles pregnant women said they encounter were mainly centered around their clinical experience: long waiting times, vaccine shortages, and impolite behavior of healthcare providers or clinical staff. CONCLUSION: Important advances have been made in Latin America to promote maternal immunization. Results from this study show that an important aspect that remains to be addressed, and is crucial in improving vaccine uptake in pregnancy, is women's clinical experience. We recommend pregnant women to be treated as a priority population for providing immunization and related healthcare education. It is imperative to train healthcare providers in health communication so they can effectively communicate with pregnant women regarding maternal vaccines and can fill knowledge gaps that otherwise might be covered by unreliable sources dispensing inaccurate information.

Health care providers perspectives about maternal immunization in Latin America.

BACKGROUND: Antenatal care providers have a key role in providing appropriate information and immunization recommendations to improve pregnant women's vaccine uptake. The objective of this study is to describe health care providers' perspectives and experience regarding the implementation of maternal immunization programs in Latin America. METHODS: We conducted 33 in-depth interviews of health care providers from Argentina, Brazil, Honduras, Mexico, and Peru (6-7 per country). Qualitative data analysis was conducted using a combination of both manual techniques and the computer software program NVivo. We identified and coded main themes related to maternal immunization. RESULTS: The main themes identified in this analysis were practices related to maternal immunization, knowledge and training, resource availability and interactions with pregnant women. Healthcare providers knew that recommendations exists but some did not know their content; they expressed concerns about insufficient training. Providers from all five countries expressed the need for additional human resources and supplies. They also expressed a desire for women to be more proactive and ask more questions during the health visits. CONCLUSION: This is the first multi-country study assessing the perspectives of health care providers about maternal immunization practices at the facility level in Latin America. Recommendations based on the results from this study include implementing additional trainings around maternal immunization, especially targeting obstetricians and midwives. These trainings should be conducted in coordination with improvements to supply chain and other structural issues.