LST1 and neoplasm: Although sygl-1 and lst-1 require FBF for tumor formation at 15°C, they unlikely drive stemness exclusively via FBF for two reasons: GSC loss is more severe in lst-1 sygl-1 double mutants than in fbf-1 fbf-2 double mutants [15, 18], and GSC loss in fbf-1 fbf-2 double mutants can be enhanced by removal of either lst-1 or sygl-1 [25; this work].