Since an antisense oligonucleotide technology (ASO) that inhibits CLU (Custirsen, OGX-011) is currently in phase III clinical trials for castration-resistant prostate cancer patients, and in phase II clinical trials for lung and breast cancer patients [39], we wished to investigate the roles played by CLU in L1-mediated CRC cell metastasis. The gene discussed is CLU; the disease is breast cancer.