The small molecule compound disulfiram has been found to display tumor inhibitory activity attributed to different properties, including ALDH1A1 inhibition [35, 162, 163], inhibition of proteasome activity [164, 165], prevention of NF-κB translocation [165, 166], induction of reactive oxygen species generation [167, 168], blockade of the PI3K/PTEN/AKT signaling pathway [169], inactivation of tumor-associated enzymes [170–172], and suppression of metastasis-associated gene expression [170, 171, 173]. This evidence concerns the gene ALDH1A1 and neoplasm.