Nitroxoline is an 8-hydroxyquinoline that has diverse biological activities, including antibacterial, antiproliferative, and bromodomain interaction-inhibiting properties.
1,2,3,4 Nitroxoline is active against the bacteria
E. coli,
S. aureus,
E. faecalis,
K. pneumoniae, and
P. mirabilis in vitro (MIC
90s = 4, 4, 8, 8, and 8 mg/L, respectively).
1 It also inhibits biofilm formation of certain strains of multidrug-resistant (MDR)
A. baumannii and
P. aeruginosa, as well as methicillin-resistant
S. aureus (MRSA) and
S. epidermidis (MRSE) with minimum biofilm eradication concentration (MBEC) values of 46.9, 1,500, 188, and 125 μM, respectively.
2 Nitroxoline inhibits the growth of human U87 and U251 glioma, A549 lung, and PC3 prostate cancer cells (IC
50s = 50, 6, 38, and 23 μg/ml, respectively).
3 In vivo, it reduces tumor growth in a PTEN- and KRAS-driven glioma mouse model when administered at a dose of 80 mg/kg per day. Nitroxoline also inhibits the interaction between the first bromodomain of bromodomain-containing protein 4 (BRD4) with acetylated histone H4 with an IC
50 value of 0.98 μM.
4