Novel Intergenically Spliced Chimera, NFATC3-PLA2G15, Is Associated with Aggressive T-ALL Biology and Outcome
MOLECULAR CANCER RESEARCH
Authors: Bond, Jonathan; Quang, Christine Tran; Hypolite, Guillaume; Belhocine, Mohamed; Bergon, Aurelie; Cordonnier, Gaelle; Ghysdael, Jacques; Macintyre, Elizabeth; Boissel, Nicolas; Spicuglia, Salvatore; Asnafi, Vahid
Abstract
Leukemias are frequently characterized by the expression of oncogenic fusion chimeras that normally arise due to chromosomal rearrangements. Intergenically spliced chimeric RNAs (ISC) are transcribed in the absence of structural genomic changes, and aberrant ISC expression is now recognized as a potential driver of cancer. To better understand these potential oncogenic drivers, high-throughput RNA sequencing was performed on T-acute lymphoblastic leukemia (T-ALL) patient specimens (n = 24), and candidate T-ALL-related ISCs were identified (n = 55; a median of 4/patient). In-depth characterization of the NFATC3-PLA2G15 chimera, which was variably expressed in primary T-ALL, was performed. Functional assessment revealed that the fusion had lower activity than wild-type NFATC3 in vitro, and T-ALLs with elevated NFATC3-PLA2G15 levels had reduced transcription of canonical NFAT pathway genes in vivo. Strikingly, high expression of the NFATC3-PLA2G15 chimera correlated with aggressive disease biology in murine patient-derived T-ALL xenografts, and poor prognosis in human T-ALL patients.
Mechanisms of intermittent hypoxia induced hypertension
JOURNAL OF CELLULAR AND MOLECULAR MEDICINE
Authors: Bosc, Laura V. Gonzalez; Resta, Thomas; Walker, Benjimen; Kanagy, Nancy L.
Abstract
Introduction Mechanisms of IH-induced systemic hypertension Contribution of the nervous system Contribution of circulating and vascular factors Role of transcription factors in the inflammatory and cardiovascular consequences of IH NF-kappa B NFAT HIF-1 Intermittent hypoxia induced pulmonary hypertension Conclusions Exposing rodents to brief episodes of hypoxia mimics the hypoxemia and the cardiovascular and metabolic effects observed in patients with obstructive sleep apnoea (OSA), a condition that affects between 5% and 20% of the population. Apart from daytime sleepiness, OSA is associated with a high incidence of systemic and pulmonary hypertension, peripheral vascular disease, stroke and sudden cardiac death. The development of animal models to study sleep apnoea has provided convincing evidence that recurrent exposure to intermittent hypoxia (IH) has significant vascular and haemodynamic impact that explain much of the cardiovascular morbidity and mortality observed in patients with sleep apnoea. However, the molecular and cellular mechanisms of how IH causes these changes is unclear and under investigation. This review focuses on the most recent findings addressing these mechanisms. It includes a discussion of the contribution of the nervous system, circulating and vascular factors, inflammatory mediators and transcription factors to IH-induced cardiovascular disease. It also highlights the importance of reactive oxygen species as a primary mediator of the systemic and pulmonary hypertension that develops in response to exposure to IH.