PROX1 and neoplasm: To address this and maximize genetic specificity in vivo, tumors were established by injecting LLC tumor cells into the left caudal/medial inguinal fold of Ndst1f/fProx1+/CreERT2 mutant mice (N = 10) and Ndst1f/fProx1-/CreERT2 wildtype littermates (N = 10), wherein the Ndst1 mutation could be inducibly driven under control of the Prox1 promoter, which is expressed exclusively in lymphatic endothelium [43].