KRAS and colorectal cancer: Interestingly, IPA3 inhibits the proliferation of melanoma and colorectal cancer cells with mutations at KRAS or NRAS better, than those containing mutations at BRAF. Treatment of cells with IPA3 or ectopic expression of DN PAK1 sensitized cell with RAS mutations to the B-Raf inhibitor GDC-0897 or the MEK inhibitor ZD6244.