claim: Ann Biderman was born on August 15th, 1951.
evidence: A mesenchymal -- epithelial transition -LRB- MET -RRB- is a reversible biological process that involves the transition from motile , multipolar or spindle-shaped mesenchymal cells to planar arrays of polarized cells called epithelia .. MET is the reverse process of epithelial -- mesenchymal transition -LRB- EMT -RRB- .. Unlike epithelial cells -- which are stationary and characterized by an apical-basal polarity , tight junctions , and expression of cell-cell adhesion markers such as E-cadherin , mesenchymal cells do not make mature cell-cell contacts , can invade through the extracellular matrix , and express markers such as vimentin , fibronectin , N-cadherin , Twist , and Snail .. extracellular matrix. extracellular matrix. METs occur in normal development , cancer metastasis , and induced pluripotent stem cell reprogramming .. TOC