Engineering tumors: a tissue engineering perspective in cancer biology.

There is increasing recognition that three-dimensional (3D) tissue culture technologies have many uses within the biomedical sciences beyond the scope of regenerative medicine. One such use is in the field of cancer biology, where a 3D tumor model that accurately recreates the in vivo tumor phenotype would be a valuable tool for studying tumor biology and would allow better preclinical evaluation of anticancer drug candidates. The most widely used model involves small cellular aggregates, termed spheroids, which have been used by cancer biologists for decades and have consistently shown the superiority of 3D tissue culture over standard two-dimensional monolayer culture for mimicking the tumor behavior and drug resistance encountered in vivo. Currently, several research groups have begun to adapt more advanced 3D culture techniques from the tissue engineering field to create a more clinically accurate ex vivo model of tumor biology.