NFKB1 and cancer: In the present study, we thus aimed: (i) to screen potential repurposing drugs for anticancer therapy by using the 3D tumoroid multiplex reporter system, (ii) to investigate whether one compound, Benz, could act as an anticancer agent suppressing tumor progression in vitro and in vivo, and reducing circulating tumor cells and metastasis, and (iii) to reveal a mechanism of action (MoA) of Benz in targeting cancer cells by acting on cell surface molecules and by altering key pro-tumorigenic signaling transactivators such as STAT, NF-κB, and β-catenin.