ABSTRACT
A microcapsule is a spherical, with a diameter that can be controlled in the range of 200 -1500 μm and biocompatible semipermeable membrane, which allows the bidirectional diffusion of nutrients,oxygen, secreted therapeutic product, and waste but prevents the penetration of high molecular weight substances from the microcapsule, such as antibodies and immunocytes. In comparison to monolayer culture and multicellular tumor spheroid model, orthotopic injection of microencapsulated tumor cells has uncomparable advantages in cell proliferation, mimicking the in vivo situation, making orthotopic tumor model and distant organ metastases model. Microencapsulated tumor assay has the potential of being widely used for in vitro anticancer drug screening and evaluation of the effects. This article mainly reviews the advantages of microencapsulated tumor assay and its application.