For example, the isogenic DLD1 KRAS+/−, KRASG13D/−, PIK3CA+/−, and PIK3CAE545K/− colorectal cancer cell lines exhibited substantially different growth kinetics and sensitivity to the MEK inhibitor PD 0325901 depending on whether cells were cultured in 2D or 3D conditions despite their identical, isogenic status [23]. Here, KRAS is linked to colorectal cancer.