GSK3B and neoplasm: In particular, a lot of data are being accumulated about the beta isoform acting as a tumor suppressor in some cancers while potentiating tumoral growth in others: for example, GSK3B activation can be crucial in mediating caspase-dependent apoptosis by contributing to p53 activation in certain epithelial cancers [10], whereas its inhibition arrests pancreatic tumor growth in vivo [11] and is synthetically lethal with MLL oncogene defects in a subset of human leukemia [12].