3,3′-diindolylmethane or diindolylmethane (DIM), a natural product from cruciferous vegetables, which possesses chemopreventive activity in all stages of breast cancer carcinogenesis and is under investigation for the different form of cancer. DIM selectively induced proteasome-mediated degradation of the class I histone deacetylases (HDAC1, HDAC2, HDAC3, and HDAC8) without affecting the class II HDAC proteins (HDAC4, 5, 6, 7, and 10). Histone deacetylases are components of high molecular weight multisubunit complexes of co-repressor proteins that are recruited by transcription factors to the promoters to regulate gene expression. In addition, was identified another mechanism of action: DIM suppressed cancer cells proliferation and miR-30e down-regulated during this effect. miR-30e targeted the 3'-UTR of ATG5 to inhibit its translation. Thus DIM may through the miR-30e-ATG5 modulating autophagy inhibit the proliferation of gastric cancer cells. DIM is also sold as absorption-enhanced formulation under the brand name Patented BioResponse DIM®. BioResponse DIM supports a more favorable metabolism of estrogen and supports the production of 2 hydroxyestrone and 2-methoxyestrone, key metabolites in men and women. DIM is used to treat recurrent respiratory papillomatosis and it has been studied for patients with cervical intraepithelial neoplasia.