Additional genes harboring somatic mutations that have been characterized as cancer genes in our study include, APC, TGFβ3, SMAD4, BCL2, INPPL1, INPP4B, PIK3CA, PTPRE and KDR. Mutations in the APC gene have been identified in sporadic cancers and play a role in the WNT/β-catenin signaling pathway. The gene discussed is PIK3CA; the disease is cancer.