Additionally, the PI3K/Akt/mTOR pathway is also altered in NSCLC, especially in squamous cell lung cancer;26 the crosstalk between Ras/Raf/MEK and PI3K/Akt/mTOR signalling pathways makes NSCLC treatment even more challenging, since inhibiting one pathway may lead to corresponding activation of the other due to blocking negative regulation. Here, MTOR is linked to squamous cell lung carcinoma.