Cell Differentiation Yesterday and Today

Abstract

Not really yesterday: this story starts half a century ago, when I was a medical student in the University of Brussels. We had, among other things, lectures in histology, embryology and pathology. I remember very well A. Dalcq’s lectures on morphogenetic movements, neural plate induction, germ layers formation, and organogenesis. I have not forgotten P. Gerard’s description of tissues and organs. Perhaps still more vivid in my mind remains the discussion by Albert Dustin (who discovered the inhibition of mitosis by colchicine) of the mysterious causes of cancerous metaplasia: is the metaplasia due to chemicals (tar in the case of chimney sweepers) or to physical agents (UV for sailors)? Is it contagious and due to a virus? Or hereditary? An enormous amount of work has been undertaken since 1930 in order to answer these questions; yet we do not know for certain whether cancerous transformation is due to a multiplicity of causes or to a single one as mutation of “cancer genes”.

Due to illness, Dr. Brachet was unfortunately unable to attend the Minneapolis Conference