Preface

Excerpt

Welcome to this timely special Cancer and Metastasis Reviews issue on the small, often unheeded, but mighty platelet. Small yes, but mighty you say? Well, they do not have nuclei and the human platelets are 2–3 μm in size. This makes them difficult to distinguish on pathologic review when compared to nucleated cells that are morphologically easier to track and generally approach 10–30 μm in size. Ironically, the stage II megakaryocyte found in the bone marrow ranges from 20 to 80 μm and is one of the largest cells in the human body, thus they are of mighty lineage. Particularly since, the estimated number of platelets that are made each day to initiate their 7–10 day suicidal journey in the blood stream approaches 100 billion. Thus, in any given platelets-driven biological reaction or process there is the potential for extremely large numbers small platelets being in volved in a swarm-like fashion to supress a threat or secure a lesion. So much like a swarm of bees, the sheer numbers of of small platelets potentially involved adds to their effective might. Additionally from a biophysical standpoint, the platelets’ small size and discoid shape allow them to patrol in the fluid shear fields of the circulation near the vascular walls along with aiding in damage or pathogen threat recognition. Platelets also provide most of the growth factors released into serum following coagulation along with factors that influence vasoconstriction, thrombogenesis, coagulation, clotting, fibrinolysis, wound formation and repair, angiogenesis, inflammation, immune modulation, along with cancer progression and metastasis. So, small and definitely yes, they are mighty. …