The second was a colon cancer cell line HCT116, which is heterozygous for the H1047R PIK3CA mutation, PI3Kα (H1047R/+), paired with cells in which the mutant allele has been knocked-out to render the cells functionally WT, PI3Kα (+/−). The gene discussed is PIK3CA; the disease is malignant colon neoplasm.