Figure 3.
The tumor spheroid as a three-dimensional model for recapitulating the environmental cues originating from the high density of cancer cells such as a physical barrier against drug delivery, the concentration gradient of oxygen and nutrition, and low pH in the core of the tumor mass. (A) Representative features of tumor spheroids in terms of the physiological similarity with the native tumor. (B-a) The response of prostate cancer cell (LNCaP) spheroids in the aggregated form against the anticancer drug docetaxel. (B-b) The difference in cell viability depending on the culture dimension. Reprinted with permission from Chambers et al.124. (C-a) The time-dependent penetration of doxorubicin into the tumor spheroids. Red: doxorubicin. (C-b) The size-dependent chemoresistance of human breast adenocarcinoma spheroids against doxorubicin. Reprinted with permission from Gong et al.127.