GADD45A and breast cancer: Moreover, the most highly enriched gene set in the C6 collection (NES = 1.70, FDR = 0.05) corresponded to genes in MCF-7 breast cancer cells adapted for estrogen-independent growth in culture that were upregulated in the carfilzomib-resistant MM cells; KLF4 and GADD45A were included in the leading edge subset (Figure 3B).