Clinical cardiac regenerative studies in children

Integrated analysis of telomerase enzymatic activity unravels an association with cancer stemness and proliferation

Active telomerase is essential for stem cells and most cancers to maintain telomeres. The enzymatic activity of telomerase is related but not equivalent to the expression of TERT, the catalytic subunit of the complex. Here we show that telomerase enzymatic activity can be robustly estimated from the expression of a 13-gene signature. We demonstrate the validity of the expression-based approach, named EXTEND, using cell lines, cancer samples, and non-neoplastic samples. When applied to over 9,000 tumors and single cells, we find a strong correlation between telomerase activity and cancer stemness. This correlation is largely driven by a small population of proliferating cancer cells that exhibits both high telomerase activity and cancer stemness. This study establishes a computational framework for quantifying telomerase enzymatic activity and provides new insights into the relationships among telomerase, cancer proliferation, and stemness.

Autologous skeletal myoblast sheet implantation for pediatric dilated cardiomyopathy: A case report

BACKGROUND

In children with dilated cardiomyopathy, heart transplantation is the last treatment option. However, new regenerative treatments, such as cell therapy, have attracted scientific attention. We have previously demonstrated the efficacy of autologous skeletal myoblast sheet implantation for treatment of ischemic and dilated cardiomyopathy in adults. Because of the mechanism underlying this cell therapy, a similar effectiveness is expected for patients with pediatric dilated cardiomyopathy.

CASE

Herein, we describe the case of a child with dilated cardiomyopathy who underwent an autologous skeletal myoblast sheet implantation, which proved to be safe, and led to sustained maintenance and improvements in cardiac function and clinical status.

Regenerative therapies in young hearts with structural or congenital heart disease

Pediatric heart failure (HF) is rare. The prognosis is generally poor. HF is most frequently related to cardiomyopathy or congenital heart disease (CHD). Associated phenotypes are HF with preserved (HFpEF) or reduced ejection fraction (HFrEF); both in children with biventricular or univentricular circulation. Cardiac growth, differentiation, proliferation and consecutively regenerative and repair mechanisms are inversely related to the patient's age; edaphic and circulating cardiac progenitor cells as well; in sum, there are enormous endogenous potentials repairing a diseased heart in particular in young children. Efforts supporting pediatric cardiac regeneration are clearly justified; cell-based therapies have been addressed in small series of children with end-stage HF of either the left or right ventricle, more recently in randomized clinical trials. Different cell populations like autologous bone marrow mononuclear cells, progenitor cells or cardiac derived cells have been injected into coronaries or directly into the myocardium. Beneficial at least transient improvement of cardiac function was observed in patients with dilative cardiomyopathy and CHD, mainly hypoplastic left heart syndrome (HLHS). Cellular repopulation and possibly more crucial, paracrine effects contributed in slowing down progression of pediatric end-stage HF. Our review summarizes the current knowledge in different scenarios of HF by cell-based cardiac therapies in critically ill children. Based on the actual clinical experience future work to distinguish responders from non-responders among other refinements will lead to individualized precision treatment of HF in children, what means a lot to a child on a long list waiting for heart transplantation (HTX).