Immunofluorescence picture (200×) of a murine papillary thyroid carcinoma stained for galectin- 3 (green) and DAPI (blue). This mouse model, developed in the McMahon Lab at the University of California, San Francisco by R.-P. Charles using the cre-activable gene Braf^CA mutant mouse coupled with a thyroid-specific cre-recombinase (Thyro-cre^ERT2), mimics closely the human pathology (e.g., galectin-3 expression). This preclinical model is invaluable for further studies using pathway-targeted drug treatments but also for uncovering the genetics behind tumor progression to anaplastic thyroid carcinoma by combining additional genomic alterations like Pik3ca^H1074R or Pten deletion. See the article by Charles and colleagues (beginning on page 979) for more information.