Researchers have generated a new mouse model in which Kras is activated and p53 is deleted in thyroid follicular cells. The animals developed papillary thyroid cancer that progressed to poorly differentiated thyroid tumours similar to human tumours. The tumours were resistant to apoptosis, but treatment with obatoclax, a small-molecule inhibitor of Bcl2, induced cell death. The researchers suggest that these findings might uncover new therapeutic targets.