There was a trend for colorectal cancer cell lines carrying KRAS mutation (HCT-15, HCT116, DLD-1, LoVo and SW480) to be more resistant to serine and glycine withdrawal compared to those cell lines carrying BRAF mutations (RKO, HT-29, SW1417 and CL-34), although SW620 (KRAS mutant) and VACO5 (BRAF mutant) were exceptions to this trend (Fig. 1b and Supplementary Figure 1a). This evidence concerns the gene BRAF and colorectal cancer.