Diagnostic classification of childhood cancer using multiscale transcriptomics.

The causes of pediatric cancers' distinctiveness compared to adult-onset tumors of the same type are not completely clear and not fully explained by their genomes. In this study, we used an optimized multilevel RNA clustering approach to derive molecular definitions for most childhood cancers. Applying this method to 13,313 transcriptomes, we constructed a pediatric cancer atlas to explore age-associated changes.

Involvement of mesenchymal stem cells in cancer progression and metastases.

Mesenchymal stem/stromal cells (MSCs) are known to be the helpers for the healing of tissue damage, often referred to as ambulatory cells. However, MSCs are also recruited by cancer cells to similarly aid in tumor growth and progression. In this review, some of the key steps in cancer progression and metastases are described including the various steps in which MSCs participate and may play important roles.

Phospholipase C signaling tonically represses basal atrial natriuretic factor secretion from the atria of the heart.

The cardiac hormone atrial natriuretic factor (ANF or ANP) plays significant, well-established roles in a large number of physiological and pathophysiological processes, including water and electrolyte balance, blood pressure regulation, and cardiovascular growth. Understanding the regulation of its production and secretion by atrial cardiomyocytes is incomplete. We have previously established a significant role of G(i/o) protein signaling in modulating ANF secretion as promoted by stretch of the atrial myocardium.

Emphasizing the need to more fully understand development: a stem cells and regenerative medicine meeting report.

A shared enthusiasm towards the highly promising utility of stem cell research brought together clinicians and scientists from academic institutions, government, and industry at the Second Annual International Stem Cells and Regenerative Medicine meeting presented by GeneExpression Systems, Inc. earlier this year. A common theme was echoed by presenters that a deeper understanding of natural development of the whole organism and individual organ systems is needed.

Cardioprotective stress response in the human fetal heart.

Objective: We propose that the fetal heart is highly resilient to hypoxic stress. Our objective was to elucidate the human fetal gene expression profile in response to simulated ischemia and reperfusion to identify molecular targets that account for the innate cardioprotection exhibited by the fetal phenotype.

Methods: Primary cultures of human fetal cardiac myocytes (gestational age, 15-20 weeks) were exposed to simulated ischemia and reperfusion in vitro by using a simulated ischemic buffer under anoxic conditions.

Participation of G proteins in natriuretic peptide hormone secretion from heart atria.

The involvement of G proteins in the mechanism underlying the increased atrial natriuretic factor (ANF) secretion observed after atrial muscle stretch (stretch-secretion coupling) was assessed using a combined pharmacological, immunocytochemical, and tissue fractionation approach. It was found that G(i/o) inhibition by pertussis toxin (PTX) abolished stretch-secretion coupling without affecting baseline secretion through a mechanism that is independent of G(q) signaling agonists. Mastoparan-7, a G(i/o) agonist, significantly increased ANF secretion even in the absence of muscle stretch through a PTX-sensitive mechanism.