Besides the homogeneous, nonfibrillar characteristics [36] and flipped Col IV and laminin ratios compared to native basement membrane compositions [25], the different growth factors that can be many folds above serum levels (even after growth factor reduction) and some underdefined constituents inherent to the EHS tumor confine the biological research applications of Matrigel as well as the interpretations for the phenotypes and mechanisms therein. The gene discussed is LAMB2; the disease is neoplasm.