Results indicated that 1 μM gefitinib did not inhibit PI3K activation in HCT116 cells although the gefitinib-induced inhibitory effect on the complexing of K-ras/PI3K and K-ras/Raf has been observed in co-mutant K-ras/PTEN or K-ras/PIK3CA NSCLC cells [12]. The gene discussed is PIK3CA; the disease is non-small cell lung carcinoma.