Chromomycin A3 is an aureolic acid-type antitumor antibiotic. Chromomycin A3 has a variety of utilities as a staining agent for human sperm chromatin, autophagy inducing agent, and apoptosis inhibitor.
Chromomycin A2 is an aureolic acid that has been found in several marine actinomycetes and has antibacterial and anticancer activities. Chromomycin A2 inhibits the growth of B. subtilis in an agar diffusion assay. It also inhibits the growth of human SGC7901 gastric cancer, HepG2 hepatocellular carcinoma, A549 lung epithelial adenocarcinoma, HCT116 colon cancer, and COC1 ovarian cancer cells, as well as human umbilical vein endothelial cells (HUVECs; IC50s = 4, 0.5, 3, 5, 5, and 8 nM, respectively). Chromomycin A2 (30 nM) halts the cell cycle in the G0/G1 phase and increases the protein levels of LC3A and LC3B in MALME-3M melanoma cells, indicating that it induces autophagy. It also increases the levels and promoter activity of the autophagic proteins ATG7 and ATG10 and reduces cell viability to 50% in human SCC-11 squamous cell carcinoma cells when used at a concentration of 30 nM.