MTOR and small cell lung carcinoma: Those cell lines, Nutlin-3 insensitive, showed the remarkable sensitivity to the dual inhibitor of mTOR-PI3K.54 In addition, preclinical study found chemoresistance could be reversed by the PI3K/AKT/SOX2 signaling pathway in SCLC.55 More and more PI3K and mTORC1/2 inhibitors, single or dual, were designed for the patients in phase I study.56 Molecular alterations in the PI3K/AKT/mTOR signaling pathway are considered to be a precise therapeutic priority in SCLC for the selection of patients, who are potentially sensitive to PI3K/AKT/mTOR inhibitors.