No association was found for either KRAS or BRAF – two genes that, when mutated, have important therapeutic and/or prognostic implications in metastatic colorectal cancer; however, statistically significant lower Src and FAK activity was detected in the presence of NRAS and CTTNB1 mutations (P < 0.01 for all). This evidence concerns the gene PTK2 and metastatic colorectal cancer.