In the NRASmut melanoma cell lines, although MEK inhibitor plus PI3K inhibitor had a superior inhibition than the combination of MEK and mTOR inhibitors (mTOR inhibition can activate upstream AKT [253]), MEK inhibitor plus mTOR inhibitor also have an effective inhibition of the cell growth and regression of xenograft model [65]. The gene discussed is PIK3CB; the disease is melanoma.