Tumour metastasis is an important reason for cancer death, and cancer cell migration is an important step in the process of tumour metastasis. Studying cancer cell migration is of great significance. Here, we present a novel microfluidic co-culture system and establish mild, moderate and severe cancer models by using HMEpiC and MDA-MB–231 cells to study cancer cell migration and anti-cancer drug screening. Using this device, we achieved high cell viability (over 90%) and a stable analysis of the migration ability of cancer cells. We observed that the density of the cancer cells determined the probability of the occurrence of metastatic cells and that the induction of normal cells affected the metastatic velocity of each cancer cell. We verified that the increase in the migration ability of MDA-MB-231 cells co-cultured with HMEpiC cells was relative to the increased secretion of IL-6 and that this was verified by an IL-6 inhibitor assay. This co-culture also led to decreased CK-14 secretion and morphological changes in HMEpiC cells. Finally, significant inhibition of paclitaxel and tamoxifen on cancer migration was observed. Taken together, our microfluidic device could be a useful tool for the quantitation of the migratory capability and anti-metastatic drug screening.

In this review, we summarized the interinfiltration of 3D printing technology and microfluidic technology in organ-on-chip fabrication.

Tumour invasion into the surrounding stroma is a critical step in metastasis, and it is necessary to clarify the role of microenvironmental factors in tumour invasion. We present a microfluidic system that simulated and controlled multi-factors of the tumour microenvironment for three-dimensional (3D) assessment of tumour invasion into the stroma. The simultaneous, precise and continuous arrangement of two 3D matrices was visualised to observe the migration of cancer cell populations or single cells by transfecting cells with a fluorescent protein. A vascular endothelial layer was formed to simulate transendothelial transport of nutrients, and its endothelial barrier function was verified by the diffusion of 70 kDa fluorescein isothiocyanate (FITC)-Dextran in 3D matrices. Through high-throughput cell migration tracking observation and statistic evaluation, we clarified that cell density of the tumour directly determined its invasiveness. The results suggested that increased secretion of IL-6 among both cancer cells (MDA-MB-231) and noncancerous cells (MCF-10A or HDF-n) after co-culture contributes to cancer cell invasiveness, and this was verified by an IL-6 inhibitor assay. Finally, the drug efficacy of paclitaxel was reflected as changes in cancer cell migration ability, viability, and morphology. Together, our microfluidic devices could be a useful tool to study the mechanism of tumour invasion into the stroma and to screen anti-metastatic drugs.