A simple in vitro model for human organ-to-organ interaction studies was realized by using spherical microtissues (MTs) cultured in a 96-well-format-based microfluidic platform. The model was validated by comparing the bio-activation effects of an anti-cancer pro-drug, cyclophosphamide (CPA), under static and perfusion conditions in a liver-tumor network. Primary human liver (hLi) MTs and human colon carcinoma (HCT116) MTs were fluidically interconnected for realizing a liver-tumor model in a physiological environment. Medium was perfused through microfluidic channels without tubing and pumps by using a gravity-driven flow concept
