Comparative expression analysis of carfilzomib-resistant and parental LP-1 human multiple myeloma cells

LP-1 cells were exposed to stepwise increasing concentrations of carfilzomib over a period of 18 weeks: cells adapted to growth in 4 nM carfilzomib by 4 weeks, in 6 nM in another 6 weeks and in 12 nM after a further 8 weeks. The resulting cell culture, denoted LP-1/Cfz, retained resistance to carfilzomib even when tested after removal of selective pressure for approximately 8 weeks. LP-1/Cfz cells were profiled for gene expression after 1 week of growth in the absence of carfilzomib together with parental LP-1 cells which had not been selected in the drug (triplicate samples).