In our in vitro study using the selected TNBC cell line, MDA-MB-231, we generated CRISPR/Cas9-mediated, isoform-selective ADK knockdown in breast cancer cell lines and further evaluated the role of these two ADK isoforms on phenotypic changes of MDA-MB-231 cells with engineered manipulation of ADK-L or ADK-S. Here, ADK is linked to breast cancer.