Optimization of the tissue source, malignancy, and initial substrate of tumor cell-derived matrices to increase cancer cell chemoresistance against 5-fluorouracil

The low chemoresistance of in vitro cancer cells inhibits the development of new anti-cancer drugs. Thus, development of a new in vitro culture system is required to increase the chemoresistance of in vitro cancer cells. Tumor cell-derived matrices have been reported to increase the chemoresistance of in vitro cancer cells. However, it remains unclear how tissue sources and the malignancy of cells used for the preparation of matrices affect the chemoresistance of tumor cell-derived matrices. Moreover, it remains unclear how the initial substrates used for the preparation of matrices affect the chemoresistance. In this study, we compared the effects of tissue sources and the malignancy of tumor cells, as well as the effect of the initial substrates on chemoresistance against 5-fluorouracil (5-FU). The chemoresistance of breast and colon cancer cells against 5-FU increased on matrices prepared with cells derived from the corresponding original tissues with higher malignancy. Moreover, the chemoresistance against 5-FU was altered on matrices prepared using different initial substrates that exhibited different characteristics of protein adsorption. Taken together, these results indicated that the appropriate selection of tissue sources, malignancy of tumor cells, and initial substrates used for matrix preparation is important for the preparation of tumor cell-derived matrices for chemoresistance assays.