To confirm that full-length BRG1 also binds p16INK4a in human cells, both proteins were co-expressed transiently in U2OS osteosarcoma cells and MYC-tagged p16INK4a was specifically co-purified with FLAG-tagged BRG1 in immunoprecipitation assays using a FLAG-specific antibody (Figure 1B). This evidence concerns the gene SMARCA4 and osteosarcoma.