To explore the function of 66CTG in the proliferation of cancer cells, we prepared a specific antibody for 66CTG, and utilized two siRNAs to specifically knock down 66CTG expression in two cell lines of TNBC, including BT549 and MDA-MB-468 (Fig. 2a, d), as the expression levels of the 66CTG-encoding gene CDKN2B-AS1 are relatively high in these two cell lines (Supplementary Fig. 1g). Here, CDKN2B is linked to cancer.