For example, Smit et al. [56] established a stable CTC cell line, CTC-MCC-41, from CRC patients and found that low concentrations of Akt inhibitor MK2206 and mTOR inhibitor RAD001 could inhibit the growth of CTC-MCC-41, indicating that the PI3K/Akt/mTOR pathway may be a valuable drug target for inhibiting CRC metastasis. This evidence concerns the gene MTOR and colorectal carcinoma.