TJP1 and sarcoma: Compared to TMG and Col I, Matrigel naturally carries certain ligands and growth factors native to mouse sarcoma tissues but has minimum collagen and other major ECM protein contents [37, 39], and therefore may maintain the dedifferentiation states of the cancer cells better than TMG and Col I, as reflected by the expression levels of Vim, E-cad, and ZO-1 in the cancer cells.