Fig. 1
CRISPR–Cas9 screen identifies SIRT6 as a determinant of melanoma drug resistance. a Schematic of the CRISPR–Cas9 screen for chromatin factors that regulate dabrafenib (BRAFi) and dabrafenib + trametinib (BRAFi + MEKi) resistance in SKMel-239 BRAFV600E melanoma cells. b Scatterplot of enrichment of sgRNAs after 6 weeks of BRAFi (top) or BRAFi + MEKi treatment (bottom). Genes in the upper right quadrant represent significant hits in each screen and those indicated in color represent significant hits present in both. c (Top) Immunoblot of SIRT6 in the indicated whole-cell lysate samples in SKMel-239. Histones used as a loading control. L-C-B and SIRT6.2–7 cells were seeded at the same density and cultured in DMSO or in the presence of the MAPKi as indicated for 1 or 2 weeks. d Growth inhibition curves are shown for BRAFi (top), as well as BRAFi + MEKi (bottom) at 72 h of treatment (n = 3). Data are mean ± SEM. e. Immunoblot of SIRT6 in the indicated whole-cell lysates of SKMel-239 or MAPKi-resistant clones generated after continuous exposure to the indicated drugs. B-Actin was used as a loading control. f Immunoblot of SIRT6 in the indicated whole-cell lysates of patient-derived short-term cultures (STCs; matched samples before vemurafenib treatment (Pre) and upon disease progression (Prog)). GAPDH was used as loading control
