STK11 and neoplasm: In support of the hypothesis that LKB1 upregulation might allow tumor cells to survive to anoikis once detached from the primary tumor, a spheroid model system showed that mesenchymal tumor cells, which are normally unable to grow in suspension, acquired the ability to expand and form spheres when they expressed higher level of LKB1; upregulation of ZEB1 and CD44 was irrelevant in this regard.