DDR1 and melanoma: Immunoblot analysis of lysates from 1205Lu and MM099 cells plated on MAF‐ and FRC‐derived ECMs indicated that MAF‐derived matrices have a stronger ability to increase the levels and phosphorylation of DDR1 and/or DDR2 compared to HDF‐derived matrices (Fig EV2A), supporting a functional implication of DDR in melanoma drug tolerance.