An orally available cancer cell stemness kinase inhibitor with potential antineoplastic activity. Although the exact target has not been fully elucidated, BBI503 targets and inhibits one or more pathways involved in cancer stem cell survival. As a result, cancer stem cell (CSC) growth as well as heterogeneous cancer cell growth is inhibited. CSCs, self-replicating cells able to differentiate into heterogeneous cancer cells, appear to be responsible for both tumor relapse and metastasis.