PIK3CA and small cell lung carcinoma: Cisplatin-resistant SCLC cell lines harboring activating mutations of the mTOR pathway, particularly PIK3CA mutation, have been suppressed significantly by PIK3CA silencing and the PI3K/mTOR kinase inhibitor NVP-BEZ235, accompanied by the inhibition of Akt and ribosomal protein S6 phosphorylation in vitro [30].