PIK3CA and colorectal carcinoma: Given that previous work from our group, as well as from other groups, had shown that TIMP-1 can be predictive of outcome in CRC [20, 29–31], and that TIMP-1 can promote cancer cell survival through the PI3K/AKT signaling axis [32, 33], we reasoned that TIMP-1 could influence response to anti-EGFR therapy.