azo compounds are considered carcinogenic, but some of them show anti microbial activity. However, I did not find sufficient work recently published that reports anti cancer activity of azo compounds.
Mendez-Lucio et al. ChemMedChem. 2014 Mar;9(3):560-5. doi: 10.1002/cmdc.201300555. Toward drug repurposing in epigenetics: olsalazine as a hypomethylating compound active in a cellular context