The human colorectal cancer cell line DLD-1 contains mutations in Ras, p53, adenomatous polyposis coli (APC) and an activating mutation in the PI3K pathway component PIK3CA, a combination that leads to an overall molecular state similar to our DrosophilarasG12V p53Ri ptenRi apcRi model. Here, PIK3CA is linked to colorectal cancer.